| 1. |
- Ahlbeck Bergendahl, Ida, et al.
(författare)
-
Fisk- och skaldjursbestånd i hav och sötvatten 2016 : Resursöversikt
- 2016
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES).De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering.Rapporten omfattar 41 fiskarter uppdelade i olika bestånd, samt sju skal- och blötdjursarter.Nytt för årets upplaga är kapitlet om ekosystemtjänster. Avsnittet beskriver de fördelar människan får genom ekosystemen, till exempel hur fisk och skaldjur kommer till nytta för människan genom föda, rekreation och biologisk mångfald. Nytt för i år är också att rapportens diagram och figurer anpassats för läsare med defekt färgseende.Översikten är utarbetad av SLU Aqua på uppdrag av Havs- och vattenmyndigheten.
|
|
| 2. |
|
|
| 3. |
- Ahlbeck Bergendahl, Ida, et al.
(författare)
-
Fisk- och skaldjursbestånd i hav och sötvatten 2017 : Resursöversikt
- 2017
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES).De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering.Rapporten omfattar 41 fiskarter och sju skaldjursarter.Nytt för i år är att vi även beskriver fritidsfisket mer utförligt. Det fisket får allt större betydelse för utvecklingen av många av Sveriges bestånd av fisk- och skaldjur, till exempel sötvattens- och kustlevande arter som abborre, gädda, gös, lax, röding och öring, liksom marina arter som torsk och hummerÖversikten är utarbetad av SLU Aqua på uppdrag av Havs- och vattenmyndigheten.
|
|
| 4. |
- Augustsson, Per, et al.
(författare)
-
Improved Carrier Medium Exchange Efficiency in Acoustic Standing Wave Particle Washing
- 2006
-
Ingår i: Micro Total Analysis Systems 2006, Proceedings of µTAS 2006 Conference. ; 1, s. 627-629
-
Konferensbidrag (refereegranskat)abstract
- A microfluidic device for particle washing was designed utilizing an acoustic standing wave field in a micro channel. Particles were focused in the center of the channel by the acoustic radiation force while the original carrier media was shifted sideways (orthogonal to the flow) at a number of consecutive wash fluid flow junctions along the main flow. Experiments were carried out in order to compare the washing efficiency to that of an earlier presented particle washing device. The new wash chip removed more than 95% of the original carrier fluid in a mix of 5μm polyamide beads and green food color as compared to the older device which removed only 60% at the corresponding conditions. The particle wash performance was shown to depend on the number of consecutive wash fluid flow junctions.
|
|
| 5. |
- Axholt, Andreas, et al.
(författare)
-
A 0.25W fully integrated class-d audio power amplifier in 0.35um CMOS
- 2007
-
Ingår i: [Host publication title missing]. - 9781424415168 ; , s. 46-49
-
Konferensbidrag (refereegranskat)abstract
- A fully integrated class-D audio power amplifier using Pulse Width Modulation (PWM) technique is presented. The output stage is an H-bridge with 5.75 min wide nMOS transistors and 15 min wide pMOS transistors, which can deliver up to 0.25 W-rms to an 16 ohm load. The chip measuring 1.2x2.4 mm(2), including pads, was fabricated in a 0.35 mu m CMOS process. It uses a single 3.3 V supply and a PWM carrier frequency of 2.5 MHz. The chip was designed and simulated with Cadence IC design tools as a student project in the course IC-project and verification at Lund University. The chip was verified and works well with a measured THD+N of 0.5% and efficiency of 76% at 0.25 W-rms output power into 16 ohm.
|
|
| 6. |
- Bjerke, Axel, et al.
(författare)
-
Machinability improvement by in-operando Tool Protection Layers through designed steel alloying : The case of manganese steel
- 2024
-
Ingår i: Journal of Materials Processing Technology. - : Elsevier BV. - 0924-0136 .- 1873-4774. ; 330
-
Tidskriftsartikel (refereegranskat)abstract
- Improvements in machinability by alloying of the workpiece often adversely impact the end user properties of a material. For example, the common use of non-metallic inclusions can lead to improved tool life during turning or milling, but often adversely affects weldability, corrosion, and wear resistance. A cutting tool material meets kilometers of workpiece material during a machining operation. Hence elements in small quantities in the workpiece may insignificantly affect the end user properties but may have large effects on tool wear. One such effect is the formation of refractory and wear resistant reaction products between the workpiece and tool. Such reaction products forming on tool surfaces may lead to improved machinability. This paper proposes the use of small amounts of alloying to induce such a Tool Protection Layer. Additionally, the paper develops a computational framework for designed alloying which balances formation of Tool Protection Layers, its in-process retention, and the functional properties of the alloy. The method has been validated for a case of manganese steel. The calculations were validated first by a wide range of diffusion experiments. Then by industrial turning of cast alloys, by comparing one reference and two newly designed alloys based on the alloying concept. The alloy with 0.003 mol fractions of Al resulted in more than 3 times increase in tool life, due to in-operando formation of Al2O3 Tool Protection Layer. The designed manganese steel maintained its functional properties with respect to abrasive wear resistance and retained its ability to work harden.
|
|
| 7. |
- Bjursten, Henrik, et al.
(författare)
-
Particle separation using ultrasound can be used with human shed mediastinal blood.
- 2005
-
Ingår i: Perfusion. - : SAGE Publications. - 1477-111X .- 0267-6591. ; 20:1, s. 39-43
-
Tidskriftsartikel (refereegranskat)abstract
- Shed mediastinal blood collected by cardiotomy suction has been shown to be a large contributor to lipid microemboli ending up in different organs. The aim of this study was to test the separation efficiency on human shed blood of a new separation method developed to meet this demand. METHODS: Shed mediastinal blood collected from the pericardial cavity of 13 patients undergoing cardiac surgery with cardiopulmonary bypass was collected. The blood was processed in an eight-channel parallel PARSUS separator, and separation efficiency was determined. RESULTS: Erythrocyte recovery, in terms of a separation ratio, varied between 68% and 91%. Minor electrolyte changes took place, where levels of sodium increased and levels of potassium and calcium decreased. CONCLUSION: This study demonstrates that PARSUS technology can be used on human shed mediastinal blood with good separation efficiency. The technology is, thereby, suggested to have future clinical relevance.
|
|
| 8. |
- Eyjolfsson, Atli, et al.
(författare)
-
Characterization of lipid particles in shed mediastinal blood.
- 2008
-
Ingår i: Annals of Thoracic Surgery. - : Elsevier BV. - 1552-6259 .- 0003-4975. ; 85:3, s. 978-981
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Shed mediastinal blood is known to be a source of microemboli in cardiac surgery. The aim of this study was to characterize in detail the lipid particles found in this blood. METHODS: Blood samples were collected from 24 patients undergoing routine cardiac surgery with cardiopulmonary bypass. Arterial and shed blood was analyzed using the Coulter counter technique to establish the number and size of particles. The composition of these lipid particles was compared with that of adipose tissue from the mediastinum using gas chromatography. Scanning electron microscopy was used to visualize the lipid particles in samples of shed blood. RESULTS: Lipid particles in the size range of 10 to 60 microm were characterized in shed mediastinal blood, and more than 300,000 particles per milliliter of blood were found. Triglyceride profiles in these lipid particles and in adipose tissue were similar, suggesting that their origin is the mediastinum. Scanning electron microscopy showed spherical formations corresponding in size to the particles counted using the Coulter counter. CONCLUSIONS: During the past decade attention has focused on microembolism in cardiac surgery, and this study has helped define the problem. Different strategies, such as eliminating the use of shed mediastinal blood or purifying the blood by different techniques, may improve the results of cardiac surgery in the future.
|
|
| 9. |
|
|
| 10. |
- Laurell, Thomas, et al.
(författare)
-
Chip integrated strategies for acoustic separation and manipulation of cells and particles
- 2007
-
Ingår i: Chemical Society Reviews. - : Royal Society of Chemistry (RSC). - 0306-0012. ; 36:3, s. 492-506
-
Forskningsöversikt (refereegranskat)abstract
- Acoustic standing wave technology combined with microtechnology opens up new areas for the development of advanced particle and cell separating microfluidic systems. This tutorial review outlines the fundamental work performed on continuous flow acoustic standing wave separation of particles in macro scale systems. The transition to the microchip format is further surveyed, where both fabrication and design issues are discussed. The acoustic technology offers attractive features, such as reasonable throughput and ability to separate particles in a size domain of about tenths of micrometers to tens of micrometers. Examples of different particle separation modes enabled in microfluidic chips, utilizing standing wave technology, are described along a discussion of several potential applications in life science research and in the medical clinic. Chip integrated acoustic standing wave separation technology is still in its infancy and it can be anticipated that new laboratory standards very well may emerge from the current research.
|
|
| 11. |
|
|
| 12. |
- Lenshof, Andreas, et al.
(författare)
-
Acoustic control of suspended particles in micro fluidic chips
- 2004
-
Ingår i: Lab on a Chip. - : Royal Society of Chemistry (RSC). - 1473-0189. ; 4:2, s. 131-135
-
Tidskriftsartikel (refereegranskat)abstract
- A method to separate suspended particles from their medium in a continuous mode at microchip level is described. The method combines an ultrasonic standing wave field with the extreme laminar flow properties obtained in a silicon micro channel. The channel was 750 mum wide and 250 mum deep with vertical side walls defined by anisotropic wet etching. The suspension comprised "Orgasol 5mum" polyamide spheres and distilled water. The channel was perfused by applying an under pressure ( suction) to the outlets. The channel was ultrasonically actuated from the back side of the chip by a piezoceramic plate. When operating the acoustic separator at the fundamental resonance frequency the acoustic forces were not strong enough to focus the particles into a well defined single band in the centre of the channel. The frequency was therefore changed to about 2 MHz, the first harmonic with two pressure nodes in the standing wave, and consequently two lines of particles were formed which were collected via the side outlets. Two different microchip separator designs were investigated with exit channels branching off from the separation channel at angles of 90degrees and 45degrees respectively. The 45degrees separator displayed the most optimal fluid dynamic properties and 90% of the particles were gathered in 2/3 of the original fluid volume.
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
- Lenshof, Andreas, et al.
(författare)
-
Improved design and performance of an acoustically operated multi channel particle separation chip
- 2005
-
Ingår i: [Host publication title missing]. ; 1, s. 575-577
-
Konferensbidrag (refereegranskat)abstract
- An improved design for acoustic particle separation in multichannel chips is presented. By wavelength matching of the microfluidic channel widths and the width of the interlacing bulk silicon, a well tuned resonating multilayer system can be accomplished. The acoustically tuned microchip offers considerable improvements in regards to particle focusing performance, i.e. separation efficiency, at fixed ultrasonic input power.
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
- Lenshof, Andreas, et al.
(författare)
-
Ultrasonic particle switching in microfluidic channels
- 2004
-
Ingår i: ; , s. 5-7
-
Konferensbidrag (refereegranskat)abstract
- Introduction It is known that suspended particles are affected by radiation forces when exposed to ultrasound. Suspended particles are gathered in the pressure nodal or pressure anti-nodal planes of an ultrasonic standing wave field depending on the density and compressibility of the particles and the medium. By combining this effect with laminar flow in a silicon micro channel different particle types can be separated from each other and/or their medium. The channel must have vertical side walls and a width chosen to correspond to half the ultrasonic wavelength. When ultrasonically actuated this results in an acoustic standing wave between the walls, perpendicular to the direction of flow. A pressure node is generated along the middle of the channel and one pressure anti-node along each channel wall. The suspended particles will be forced into the nodal or anti-nodal planes as they flow along the channel. If the end of the channel is split into three outlets the particles in the nodal plane will exit through the centre outlet while the particles in the anti-nodal planes exit through the side outlets. A large portion of the medium can be removed from one particle type by letting the main part of the medium exit through the outlets with no such particles. However, in some applications of particle separation, for example blood washing, the medium (blood plasma) can be heavily contaminated and must be totally separated from the particles (red blood cells). This can be achieved by using multiple inlets. If the inlet is split in three, like the outlet, and the suspended particles in the contaminated medium enter through the side inlets and a clean medium enters through the centre inlet the particles can be switched from the contaminated medium to the clean by the acoustic forces. Two major problems complicate blood recycling during and after surgery, fat particles and contaminations to the plasma by inflammatory components and activated coagulation factors. Fat particles are the cause of fat emboli in the brain, i.e. small brain damages that give rise to a cognitive decay. Luckily, the difference in density and compressibility between red blood cells, fat particles and blood plasma cause the red blood cells to gather in the pressure nodes and the fat particles in the pressure antinodes of the acoustic standing wave. It is therefore possible to separate the red blood cells from the fat using the method described above. Furthermore, the contaminated plasma can be replaced by clean plasma using the split inlet. Materials and methods The separation channel (350 µm wide, 125 µm deep and 20 mm long) was fabricated in <100>-silicon by double sided photolithography and anisotropic wet etch. The beginning/end of the channel had three inlet/outlet channels, one leading straight forward and one on each side at an angle of 45º to the prolongation of the separation channel. A glass lid, attached by anodic bonding, covered the channel. Rubber silicon tubings were glued to the inlets and outlets on the rear side of the chip. A piezoelectric element (2 MHz) was attached to the rear side with ultrasonic gel in between. A contaminated fluid with suspended particles was simulated by a mixture of latex spheres (5 µm in diameter), blue pigment (Evans blue) and distilled water and a clean medium with distilled water only. The same experiment was repeated using blood contaminated with “Evans blue” and non-contaminated blood plasma. A sonicated emulsion of tritium-labelled triolein (1% concentration) was used to measure the fat removal efficiency. Results and discussion More than 95% percent of the particles can be shifted from the contaminated medium to the clean and exited through the centre outlet and more than 95% of the fat particles can be removed when conditions are ideal. Less than 5% of the contaminant exited the system through the centre outlet when latex particles were shifted from contaminated distilled water to clean distilled water. The corresponding measurements on contaminated blood showed that less than 15% of the contamination followed the red blood cells out through the centre outlet. The experiments have shown that this method is a powerful particle separation tool and can be used in several blood wash applications.
|
|
| 20. |
- Lenshof, Andreas, et al.
(författare)
-
Whole blood plasmapheresis using acoustic separation chips
- 2006
-
Ingår i: [Host publication title missing]. ; 1, s. 314-316
-
Konferensbidrag (refereegranskat)abstract
- An acoustic separation system for producing pure blood plasma is presented. The separated plasma contains less than 1 % red blood cells from the original hematocrit of 40 %. A sequential separation system consisting of four separators is demonstrated.
|
|
| 21. |
- Meirose, Bernhard, et al.
(författare)
-
Real-time accelerator diagnostic tools for the max iv storage rings
- 2020
-
Ingår i: Instruments. - : MDPI AG. - 2410-390X. ; 4:3
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, beam diagnostic and monitoring tools developed by the MAX IV Operations Group are discussed. In particular, beam position monitoring and accelerator tunes visualization software tools, as well as tools that directly influence the beam quality and stability, are introduced. An availability and downtime monitoring application is also presented.
|
|
| 22. |
|
|
| 23. |
|
|
| 24. |
- Petersson, Filip, et al.
(författare)
-
Carrier medium exchange through ultrasonic particle switching in microfluidic channels
- 2005
-
Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 1520-6882 .- 0003-2700. ; 77:5, s. 1216-1221
-
Tidskriftsartikel (refereegranskat)abstract
- This paper describes a method, utilizing acoustic force manipulation of suspended particles, in which particles in a laminar flow microchannel are continuously translated from one medium to another with virtually no mixing of the two media. During the study, 5-mum polyamide spheres suspended in distilled water, spiked (contaminated) with Evans blue, were switched over to clean distilled water. More than 95% of the polyamide spheres could be collected in the clean medium while removing up to 95% of the contaminant. Preliminary experiments to use this method to wash blood were performed. Red blood cells were switched from blood, spiked with Evans blue, to clean blood plasma. At least 95% of the red blood cells (bovine blood) could be collected in clean blood plasma while up to 98% of the contaminant was removed. The obtained results indicate that the presented method can be used as a generic method for particle washing and, more specifically, be applied for both intraoperative and postoperative blood washing.
|
|
| 25. |
|
|
| 26. |
- Petersson, Filip, et al.
(författare)
-
Free flow acoustophoresis: Microfluidic-based mode of particle and cell separation
- 2007
-
Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 1520-6882 .- 0003-2700. ; 79:14, s. 5117-5123
-
Tidskriftsartikel (refereegranskat)abstract
- A novel method, free flow acoustophoresis (FFA), capable of continuous separation of mixed particle suspensions into multiple outlet fractions is presented. Acoustic forces are utilized to separate particles based on their size and density. The method is shown to be suitable for both biological and nonbiological suspended particles. The microfluidic separation chips were fabricated using conventional microfabrication methods. Particle separation was accomplished by combining laminar flow with the axial acoustic primary radiation force in an ultrasonic standing wave field. Dissimilar suspended particles flowing through the 350-mu m-wide channel were thereby laterally translated to different regions of the laminar flow profile, which was split into multiple outlets for continuous fraction collection. Using four outlets, a mixture of 2-, 5-, 8-, and 10-mu m polystyrene particles was separated with between 62 and 94% of each particle size ending up in separate fractions. Using three outlets and three particle sizes (3, 7, and 10 mu m) the corresponding results ranged between 76 and 96%. It was also proven possible to separate normally acoustically inseparable particle types by manipulating the density of the suspending medium with cesium chloride. The medium manipulation, in combination with FFA, was further used to enable the fractionation of red cells, platelets, and leukocytes. The results show that free flow acoustophoresis can be used to perform complex separation tasks, thereby offering an alternative to expensive and time-consuming methods currently in use.
|
|
| 27. |
- Petersson, Filip
(författare)
-
On acoustic particle and cell manipulation in microfluidic systems
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The combination of laminar flows in microfabricated channels and acoustic forces induced in ultrasonic standing wave fields offers new possibilities for advanced particle and cell manipulation in lab-on-a-chip applications as well as in relatively high throughput applications. Acoustic particle manipulation systems can be used e.g. to separate, wash, sort, trap or distribute particles in microfluidic networks. This doctoral thesis starts by reviewing the fundamental fields of study needed to realize such systems and to understand their potential impact. Next, the design, fabrication, operation and performance of a number of systems, based on system design principle termed the "Lund method", are described. The developed methods comprise a toolbox of generic particle handling methods that can be combined or used separately to handle biological and non-biological particles in liquid suspension. The toolbox is applied to solve various blood component handling tasks, e.g. separation of lipid particles and other contaminating substances from red blood cells and preparation of blood components. The results imply that it is possible to save thousands of people from brain damage caused by lipid particles each year, to reduce the strain on the blood banks significantly and to offer new methods for routine blood component handling. Several other important areas of application, where micrometer sized particles are routinely handled, can also be identified. Microscale acoustic particle manipulation technology is still in its infancy but, based on the findings presented in this thesis and by other researchers, it can be anticipated that new laboratory and industrial standards may very well emerge from the current research.
|
|
| 28. |
|
|
| 29. |
|
|
| 30. |
- Petersson, Leon, et al.
(författare)
-
Molecular dynamics-based characterisation of early oxide in Fe/Cr alloys
- 2022
-
Ingår i: Results in Surfaces and Interfaces. - : Elsevier BV. - 2666-8459. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- The addition of Cr is known to work as an effective prevention against oxidation in Fe-based alloys. This can be attributed to the peripheral oxide, the structure of which is dependent on the composition of the alloy. Using Molecular Dynamic (MD) calculations with a Reactive Force Field (ReaxFF) potential, we successfully identify several oxide structures arising during initial oxide formation in [100] Body-Centered Cubic (BCC) Fe1−?Cr? alloys. This structure was found to differ between the surface and bulk. Further, by gradually increasing the Cr content, we manage to track the structural Cr-dependence of both the bulk- and the surface oxide. Both in the surface and bulk, phase changes in the oxide are observed as the Cr content increases. At the surface, this takes place at around 30%–50% Cr. In the bulk, it takes place at around 30% and 70% Cr.
|
|
| 31. |
- Petersson, Ludvig, 1978-
(författare)
-
The Roles of Growth Factor Interactions and Mechanical Tension in Angiogenesis
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Angiogenesis, the formation of new blood vessels from preexisting ones through creation of new vessel branch points by sprouting or vessel splitting, is an important part of tissue growth in both physiological processes like wound healing and pathological conditions such as cancer. Growth factors like VEGF-A, FGF-2 and PDGF-BB are involved in both types of angiogenesis. Screening for genes regulated by VEGF-A stimulation in endothelial cells revealed up regulation of the endothelial cell specific glycoprotein endocan. Endocan itself did not stimulate angiogenesis. VEGF was a specific inducer since FGF-2, PDGF-BB, HGF and EGF did not alter expression. The signaling molecule PI3K was a negative regulator of endocan expression. Endocan was expressed in tumor cells and vessels, suggesting that although endocan did not directly regulate angiogenesis it can serve as a marker for angiogenic tumors. In two models of wound healing angiogenesis, the chick extra-embryonal CAM assay and the mouse cornea assay, we observed that blood vessels grew into avascular areas as functional mural cell covered loops by elongation of preexisting vessels. Loop formation was simultaneous with contraction of the avascular matrix mediated by proto/myofibroblasts. Reducing the contractibility of the stroma reduced vessel ingrowth, showing that contraction was necessary for mediating and directing growth of the vascular loops. These findings suggest a model for biomechanical regulation of vascularization that is complementary to sprouting angiogenesis which is guided by gradients of growth factors. In defining the role of growth factors, in the CAM assay, we found that FGF-2 and PDGF-BB induced vessel ingrowth, while VEGF-A, EGF and HGF did not. TGF-beta reduced the effect of FGF-2. By use of specific receptor kinase inhibitors we found an absolute requirement VEGF- and PDGF-receptor activity for vascularization while FGF- and TGF-beta-receptor function was dispensable. This suggests that functional VEGF- and PDGF-receptors are needed for vessel elongation.
|
|
| 32. |
- Reinius, Henrik, 1968-
(författare)
-
Open lung concept in high risk anaesthesia : Optimizing mechanical ventilation in morbidly obese patients and during one lung ventilation with capnothorax
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Formation of atelectasis, defined as reversible collapse of aerated lung, often occurs after induction of anaesthesia with mechanical ventilation. As a consequence, there is a risk for hypoxemia, altered hemodynamics and impaired respiratory system mechanics. In certain situations, the risk for atelectasis formation is increased and its consequences may also be more difficult to manage. Anesthesia for bariatric surgery in morbidly obese patients and surgery requiring one-lung ventilation (OLV) with capnothorax are examples of such situations.In Paper I (30 patients with BMI > 40 kg/m2 scheduled for bariatric surgery) a recruitment maneuver followed by positive end-expiratory pressure (PEEP) reduced the amount of atelectasis and improved oxygenation for a prolonged period of time. PEEP or a recruitment maneuver alone did not reduce the amount of atelectasis.In paper II we investigated whether it is possible to predict respiratory function impairment in morbidly obese patients without pulmonary disease from a preoperative lung function test. Patients with mild signs of airway obstruction (reduced end-expiratory flow) in the preoperative spirometry developed less atelectasis during anaesthesia.In paper III we developed an experimental model of sequential OLV with capnothorax using electrical impedance tomography (EIT) that in real-time detected lung separation and dynamic changes in pulmonary ventilation and perfusion distributions. OLV to the left side caused a decrease in cardiac output, arterial oxygenation and mixed venous saturation.In paper IV we used our model of OLV with capnothorax and applied a CO2-insufflation pressure of 16 cm H2O. We demonstrated that a PEEP level of 12-16 cm H2O is needed for optimal oxygenation and lowest possible driving pressure without compromising hemodynamic variables. Thus, the optimal PEEP was closely related to the level of the capnothorax insufflation pressure. With insufficient PEEP, ventilation/perfusion mismatch in the ventilated lung and redistribution of blood flow to the non-ventilated lung occurred.
|
|
| 33. |
|
|
| 34. |
|
|
| 35. |
- Ungaro, Ryan C., et al.
(författare)
-
Deep Remission at 1 Year Prevents Progression of Early Crohn's Disease
- 2020
-
Ingår i: Gastroenterology. - : W. B. Saunders Company. - 0016-5085 .- 1528-0012. ; 159:1, s. 139-147
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: We investigated the effects of inducing deep remission in patients with early Crohn's disease (CD).METHODS: We collected follow-up data from 122 patients (mean age, 31.2 ± 11.3 y) with early, moderate to severe CD (median duration, 0.2 years; interquartile range, 0.1-0.5) who participated in the Effect of Tight Control Management on CD (CALM) study, at 31 sites, representing 50% of the original CALM patient population. Fifty percent of patients (n = 61) were randomly assigned to a tight control strategy (increased therapy based on fecal level of calprotectin, serum level of C-reactive protein, and symptoms), and 50% were assigned to conventional management. We categorized patients as those who were vs were not in deep remission (CD endoscopic index of severity scores below 4, with no deep ulcerations or steroid treatment, for 8 or more weeks) at the end of the follow-up period (median, 3.02 years; range, 0.05-6.26 years). The primary outcome was a composite of major adverse outcomes that indicate CD progression during the follow-up period: new internal fistulas or abscesses, strictures, perianal fistulas or abscesses, or hospitalization or surgery for CD. Kaplan-Meier and penalized Cox regression with bootstrapping were used to compare composite rates between patients who achieved or did not achieve remission at the end of the follow-up period.RESULTS: Major adverse outcomes were reported for 34 patients (27.9%) during the follow-up period. Significantly fewer patients in deep remission at the end of the CALM study had major adverse outcomes during the follow-up period (P = .01). When we adjusted for potential confounders, deep remission (adjusted hazard ratio, 0.19; 95% confidence interval, 0.07-0.31) was significantly associated with a lower risk of major adverse outcome.CONCLUSIONS: In an analysis of follow-up data from the CALM study, we associated induction of deep remission in early, moderate to severe CD with decreased risk of disease progression over a median time of 3 years, regardless of tight control or conventional management strategy.
|
|
