<p dir="ltr">High-throughput precision agriculture is revolutionizing farming by integrating advanced technologies to enhance productivity, efficiency, and sustainability. Tools such as three-dimensional (3D) imaging, remote sensing, and data analytics enable rapid collection and processing of large data volumes, allowing farmers to make informed decisions about crop management, soil health, and resource utilization. These technologies reduce waste, minimize environmental impact, and optimize inputs like water and fertilizers, addressing global food demand and resilience to climate change. Among these tools, high-resolution 3D imaging and close-range hyperspectral and multispectral imaging are particularly valuable. High-resolution 3D imaging provides detailed spatial data on plant structures, essential for monitoring growth, drought response, and phenotyping. Meanwhile, hyperspectral and multispectral imaging captures a broad spectrum of light, revealing biochemical and physiological details, including early signs of disease and nutrient deficiencies.</p><p dir="ltr">However, applying these technologies in high-throughput precision agriculture presents challenges. Structured light phase-shifting method, despite its accuracy in 3D shape measurement, is often limited by the time-consuming requirement of multiple projected patterns for a single 3D reconstruction. To address this, we developed a method that reduces the number of required patterns by incorporating a single additional binary random pattern, combined with digital image correlation and phase-shifting, enabling high-speed 3D shape measurement. Further, we embedded this additional pattern into the fringe patterns and utilized the Semi-Global Matching algorithm to enhance measurement speed and assist in absolute phase acquisition for 3D reconstruction.</p><p dir="ltr">Similarly, while hyperspectral and multispectral imaging provide rich spectral detail, they are often compromised by illumination variations due to complex specimen geometries. To overcome this, we propose an image-based method utilizing high-resolution 3D imaging for calibrating non-isotropic point light sources, addressing challenges posed by their non-radially symmetric radiant intensity distribution and the non-Lambertian properties of the calibration target. Our experiments demonstrated the high accuracy of this calibrated light source model, which was successfully applied to estimate the relative reflectance of various surfaces.</p><p dir="ltr">Finally, we demonstrate the effectiveness of high-speed, high-resolution 3D imaging combined with multispectral imaging for leaf vein segmentation and density measurement, where venation traits serve as critical indicators of plant physiological function. We developed a multimodal imaging system capable of capturing grayscale, multispectral, and 3D data in a unified coordinate system. Additionally, we designed a leaf vein segmentation framework that leverages all three imaging modalities to test the hypothesis that integrating 3D imaging can improve vein segmentation and density measurement without the need for labor-intensive leaf clearing or destructive 2D flatbed scanning. Our findings indicate that 3D imaging provides valuable topographical information, enhancing vein segmentation, albeit with some false detections. Additionally, this approach offers clear advantages in directly measuring morphological traits, such as leaf area, vein length, and vein density, especially in unstructured environments where traditional methods often fall short.</p><p dir="ltr">In summary, this dissertation advances the fields of high-speed, high-resolution 3D imaging and multispectral imaging in precision agriculture by: (1) reducing the number of patterns required for single-frame 3D reconstruction through the integration of digital image correlation and the Semi-Global Matching algorithm with phase-shifting techniques; (2) developing an accurate non-isotropic point light source model to correct for illumination variations in multispectral images; and (3) enhancing leaf vein segmentation and vein density measurement in non-flattened sugar maple leaves using high-resolution 3D imaging. These contributions address current challenges, providing robust solutions that pave the way for more efficient and sustainable agricultural practices.</p>

Bakgrund: Djup ventrombos (DVT) är en allvarlig komplikation efter kirurgiska och ortopediska ingrepp. Detta leder till ökat lidande för patienten, längre vårdtider och därav ökade kostnader för samhället. För att förebygga DVT krävs kunskap om vilka preventiva omvårdnadsåtgärder som har effekt och hur de ska användas. Syfte: Syftet med studien var att genom en systematisk litteraturstudie se vad kunskapsläget säger om preventiva omvårdnadsåtgärder mot DVT samt vad som ser mest effektivt ut. Syftet var också att genom en enkät ta reda på hur sjuksköterskor arbetar kliniskt för att förebygga DVT. Metod: Litteraturstudie som baserades på tio orginalartiklar. Som komplement till litteraturstudien gjordes även en enkätstudie som inkluderade tio sjuksköterskor. Resultat: Tidig mobilisering tillsammans med mekanisk profylax ses som effektivt för att förebygga DVT. I många av studierna som granskats gavs patienterna lågmolekylärt heparin (LMH). Det var dock ingen lägre frekvens av DVT hos dessa patienter jämfört med de som ej fick LMH. Det var vid införandet av profylaktiska omvårdnadsåtgärder som tidig mobilisering, kompressionsstrumpor och kompressionspumpar som frekvensen av DVT sjönk. Sjuksköterskorna arbetar aktivt med förebyggande omvårdnadsåtgärder men det finns dock inga specifika riktlinjer för dessa omvårdnadsåtgärder i den kliniska verksamheten. Slutsats:  Studien visar att ett behov finns för utvecklandet av att arbeta med individanpassad profylax då patienterna utifrån olika riskgrupper har olika behov av profylaxtyper. Stor vikt bör läggas på att utveckla och implementera riktlinjer för tidig mobilisering då detta utifrån denna studies resultat har god effekt för att förebygga uppkomsten av DVT. / Background: Deep vein thrombosis is a serious complication during surgical and orthopaedic procedures. This leads to increased patient suffering, longer hospital stays and thereby also higher cost for society. To prevent DVT requires knowledge about preventive care measures that are effective, and how they will be used. Aim: The aim of this study was to examine the current state of knowledge about preventive care measures against DVT and how effective they are. The aim was also, by conducting a survey, to find out how nurses work clinically for the prevention of DVT. Study design: A literature study was conducted. The study was based on ten original articles. As a complement to the literature study a questionnaire was created and handed out to ten surgical and orthopaedic nurses. Results: Early mobilization in combination with mechanical prophylactics is seen as effective for preventing DVT. In many of the included studies patients were given low molecular weight heparin (LMH). However the frequency of DVT in these patients was not lower compared to those who did not get LMH. Instead it was at the introduction of prophylactic care measures such as early mobilization, compression stockings and compression pumps as the frequency of DVT fell. The questionnaires showed that clinical nurses worked actively with care measures. However, there were no specific guidelines for the measures in the organisation. Conclusion: The study shows that there is a need for developing methods for individual prophylactic care as patients from different risk groups have different needs. There should also be focus on developing and implementing guidelines for early mobilization as this study has shown it is effective in preventing DVT.

Im Rahmen von UPNS4D+ wird von mir der Teilbereich der automatisierten untertägigen Detektion von Gangerzlagerstätten und seltenen Erden bearbeitet. Dies erfolgt mittels eines Multisensoransatzes, der aus einer Hyperspektralkamera, einer RGB-Kamera und einem Laserscanner besteht. Die Grundlagen für die Kombination von hyperspektraler Bildverarbeitung und einer RGB-Kamera sind in der Industrie im Bereich von automatisierten Sortieranlagen zu finden. Im Bereich der Fernerkundung ist der Einsatz hyperspektraler Bilder für die Detektion geologischer Merkmale seit einigen Jahrzehnten üblich. Hier kann im Rahmen meiner Forschung gezeigt werden, dass mittels hyperspektraler Bilder Pyrit unter Tage detektiert werden kann. / In my research I work on a system which detects automatically the ore and rare earth element in a mine. This is part of UPNS4D+. For the detection I use a multi sensor system which consists of a hyperspectral camera, a RGB camera and a Laser scanner. Basics of this combination can be found in the industry. The combination of a RGB camera and a hyperspectral camera enables an automatic sorting of for example waste materials. Landsat satellites in the 1970 uses spectral information in order to detect the geology of the surface. I have tested the hyperspectral imaging in the Reiche Zeche and I can now show that Pyrite can be detected.

Thesis (MSc (Earth Sciences))--Stellenbosch University, 2008. / Detailed geological mapping and a structural analysis of auriferous quartz veins were undertaken in the Karibib region of the Pan-African Damara belt in central Namibia. The study focuses on the formation and controls of quartz-vein sets and associated lodegold mineralization in heterogeneous, siliciclastic- and marble- dominated amphibolitefacies host rocks around the Navachab gold mine and adjacent areas. Two main arrays of shallowly-dipping quartz veins can be distinguished that form a conjugate set. Steep, bedding-parallel and high-angle cross-cutting veins also occur, but play a subordinate role for mineralization. The orientation of the main conjugate set and progressive deformation of these quartz veins indicate that veining occurred during the late stages of the main phase of NW-SE directed, subhorizontal shortening (D2) and associated NW-verging folding and top-to-the-NW thrusting. Cross-cutting relationships with plutonic rocks indicate a timing of ca. 540 Ma for the mineralization. The quartz veins sets show a consistent orientation irrespective of their location with respect to NE-trending, NW-verging first-order fold structures that were previously considered to be pertinent for the mineralization. The quartz vein sets also cross-cut different lithologies at high angles. This suggests that the regional strain (D2) was the first-order control of quartz vein formation. More localized lithological and/or structural controls played, however, an important factor for the formation of economicgrade mineralization. Thick and closely spaced quartz veins in steeply dipping rocks of the Navachab open pit form a more than 150m thick economic-grade vein swarm. In this structural situation and during layer-normal subhorizontal shortening, the host rocks experienced high extensional strains in a vertical direction, favouring the formation of subhorizontal extension fractures.

The Copiapó region in northern Chile contains numerous intrusion- and volcanichosted IOCG vein systems. These veins share many features with larger IOCG systems in the region (e.g., Candelaria, Punta del Cobre), including abundant hydrothermal magnetite or hematite ± Cu, Au, REE, and other elements, and exhibit similar styles of mineralization including voluminous breccias, stockwork, and massive veins. The relatively simple geometries and small size of veins offer advantages for study of zoning and genesis in an IOCG system; and, they also provide an interesting counterpoint to classic epithermal Ag-Au veins. The vein systems exhibit systematic patterns in the alteration and mineralization zoning in both time and space. Deeper exposures are characterized by high-temperature styles of sodic and sodic(-calcic) alteration with Fe and Cu depleted vein fill assemblages. This passes upwards through a proximal zone of magnetite-dominated vein fill with sparse to absent copper, and into a magnetite-dominated, copper-bearing portion of the vein. Copper is best developed at intermediate to shallow levels in association with the hematite-dominated portions of the system. More distal, carbonate dominated facies with minor hematite and chalcopyrite are also present. Shallow levels of the vein system may be characterized by a low-sulfur style of advanced argillic alteration, that may be stratabound, in discordant breccia bodies, or structurally controlled on faults. The assemblages differ from other ore forming environments by their lack of sulfide and/or sulfate minerals, and the abundance of hypogene iron oxide phases (hematite and/or magnetite). Vein systems are dominated by brecciation events that record repeated, cyclic pulses of mineralizing fluids. Stable and radiogenic isotopic analyses, combined with fluid inclusion and mineral phase equilibria indicate the fluids were hypersaline brines (generally >40 wt% NaCl(eq)) over a temperature range of 200º-450ºC. The shallow formation, structural styles, repeated mineralization events, and size of the IOCG vein systems have many parallels to the classic precious-metal rich Ag-Au epithermal systems. Nonetheless, the two types of veins differ in their geochemistry, reflecting the large differences in fluid salinities, commonly <10 wt% NaCl(eq) in epithermal settings as compared to 15 to > 50 wt% NaCl(eq) in IOCG systems.

The plant leaf is one of the most challenging natural objects to be realistically depicted by computer graphics due to its complex morphological and optical characteristics. Although many studies have been done on plant modeling, previous research on leaf modeling required for close-up realistic plant images is very rare. In this thesis, a novel method for modeling of the leaf shape based on the leaf venation is presented. As the first step of the method, the leaf domain is defined by the enclosure of the leaf boundary. Second, the leaf venation is interactively modeled as a hierarchical skeleton based on the actual leaf image. Third, the leaf domain is triangulated with the skeleton as constraints. The skeleton is articulated with nodes on the skeleton. Fourth, the skeleton is interactively transformed to a specific shape. A user can manipulate the skeleton using two methods which are complementary to each other: one controls individual joints on the skeleton while the other controls the skeleton through an intermediate spline curve. Finally, the leaf blade shape is deformed to conform to the skeleton by interpolation. An interactive modeler was developed to help a user to model a leaf shape interactively and several leaves were modeled by the interactive modeler. The ray-traced rendering images demonstrate that the proposed method is effective in the leaf shape modeling.

No description available.

Background: The Framingham Study from 1991 showed a clear correlation between atrial fibrillation (AF) and ischemic stroke, where patients with AF had an almost fivefold increase in risk of stroke compared with patients without AF. Since then, several trials have evaluated different antithrombotic treatments to reduce the risk of stroke in patients with AF. Other trials have investigated factors that increase the risk of stroke in patients with AF and risk score systems have been developed to categorize patients into low or increased risk of stroke to help clinicians to decide which patients benefit from antithrombotic treatment and in whom it can be abstained, not to expose patients with low stroke risk to an increased risk of bleeding conferred by antithrombotic treatment. The aims of this thesis were: [1] to evaluate if a warfarin dosing algorithm can increase hit rate and decrease mean error compared with manually changed doses; [2] to assess the prevalence and net clinical benefit of aspirin as monotherapy for stroke prevention in AF; [3] to investigate the risk of thromboembolic and haemorrhagic complications within 30 days after electrical cardioversion (ECV) of AF in patients with and without oral anticoagulation (OAC) pre-treatment; and [4] to assess the proportion of patients discontinuing OAC after pulmonary vein isolation (PVI), identify factors predicting stroke after PVI and to investigate risk of complications after PVI with and without OAC. Materials and methods: All studies are retrospective and based on data from Swedish national quality registries. In paper I, data from Auricula was used to compare the resulting INR values after algorithmic warfarin dose suggestions and manually changed doses. In paper II data was extracted from the Swedish National Patient Register, the Dispensed Drugs Register and the Cause of Death Register. Patients with aspirin treatment were compared with patients without any antithrombotic treatment regarding risk of thromboembolic and haemorrhagic complications. In paper III data was collected from the Swedish National Patient Register and the Dispensed Drugs Register to examine risk of complications (thromboembolic and haemorrhagic events) within 30 days after cardioversion, comparing patients with and without oral anticoagulation pre-treatment. In paper IV data from six different Swedish national quality registries were used (Swedish Catheter Ablation Register, Auricula, Swedish National Patient Register, Dispensed Drugs Register, Cause of Death Register and Riksstroke). Patients undergoing pulmonary vein isolation (PVI) were investigated for adherence to guidelines regarding oral anticoagulation, predictors for stroke after PVI, as well as risk of ischemic stroke or intracranial haemorrhage after PVI in patients with and without treatment. Results: Paper I showed that a computerized dosing algorithm for warfarin in most cases perform as well or better compared with doses that have been changed manually, with a better hit-rate (0.72 vs. 0.67) and a lower mean error (0.44 vs. 0.48). Paper II showed that 32% of 182.678 patients with a diagnosis of AF were on monotherapy with aspirin for stroke prevention. A total of 115.185 patients were included, 58.671 with aspirin treatment and 56.514 without antithrombotic treatment at baseline. After stratification after CHA2DS2-VASc score and after multivariable adjustment, aspirin treatment did not confer a decrease in thromboembolic events. After propensity score mathcing, rate of ischemic stroke was 7.4%/year (95% CI 7.1-7.6) in aspirin treated patients and 6.6%/year (95% CI 6.4-6.9) in patients without antithrombotic treatment. In paper III 22.874 patients undergoing electrical cardioversion were included, 10.722 with and 12.152 without OAC pre-treatment. In patients with low stroke risk (CHA2DS2-VASc 0-1), no thromboembolic complication was seen within 30 days after cardioversion. In patients with CHA2DS2-VASc ≥2, the risk of thromboembolic complications was increased when no oral anticoagulation pre-treatment was used, results that remained after propensity score matching. No difference regarding haemorrhagic complications was seen. Paper IV included a total of 1585 patients undergoing PVI with a mean follow up of 2.6 years. Adherence to current guidelines regarding oral anticoagulation was good in patients with CHA2DS2-VASc ≥2. Previous ischemic stroke was a predictor for a new stroke after PVI. In patients with CHA2DS2-VASc ≥2 stroke risk was increased in patients discontinuing OAC compared to those continuing OAC (1,60%/year vs. 0.34%/year). Conclusion: Oral anticoagulation is still underutilized for prevention of stroke and systemic embolism in patients with atrial fibrillation. Patients with risk factors for stroke (CHA2DS2-VASc ≥2p) benefit from continuous oral anticoagulation treatment to prevent stroke, also in conjunction with electrical cardioversion and after pulmonary vein isolation. If warfarin is chosen, a computerised dosing algorithm can facilitate and standardize warfarin dosing and lead to better resulting INR values than manually changed doses. Aspirin should not be used for stroke prevention in patients with atrial fibrillation.

Krüppel-like factors (KLFs) are a family of 3 Cys2/His2 zinc finger transcription factors with a diverse set of roles in cellular differentiation, cell cycle regulation, tumor suppression, erythropoiesis, angiogenesis, and other processes. During embryonic development, KLF2 has a role in vessel maturation. Adult conditional KLF4 knockout mouse embryos have thickened arterial intima follow vascular injury. Breeding KLF2+/- and KLF4+/- mice resulted in the generation of KLF2/KLF4 double knockout (DKO) embryos. KLF2/KLF4 DKO embryos died by E10.5 with cranial bleeding. Using immunohistochemistry, embryo whole-mounts were examined for differences in gross vascularization between wild-type (WT), KLF2-/- and KLF2/KLF4 (DKO embryonic day 9.5 (E9.5) embryos. No obvious gross capillary abnormalities were noted in E9.5 KLF2/KLF4 DKOs, although the posterior cardinal vein appeared to narrow rostral to caudal in KLF2-/- and KLF2/KLF4 DKO embryos. Light and electronic microscopy were employed to investigate potential structural and ultrastructural phenotypes in KLF2/KLF4 DKO embryos. Microscopy confirmed hemorrhaging near and endothelial breaks in the primary head vein (PHV) in E9.5 KLF2/KLF4 DKOs (n=8) and E10.5 KLF2-/-KLF4+/- embryos (n=1). Electron micrographs illustrated a disrupted endothelium in KLF2/KLF4 DKOs with endothelial cells having filopodia-like projections. Surprisingly, KLF2-/- embryos had the presence of wider medial PHV endothelial gaps compared to WT at the electron micrograph level. Density counts revealed a 15% reduction in midline cranial mesenchyme at the level of hemorrhaging in KLF2/KLF4 DKOs compared to KLF2-/- (n=3). An in-situ hybridization localized KLF2 RNA expression to the endothelium of the PHV. A quantitative reverse transcriptase polymerase chain reaction assay revealed that the eNOS expression is synergistically regulated by KLF2 and KLF4, as a shared downstream target. It is proposed that KLF2 and KLF4 share in the regulation of multiple gene targets, leading to early death by E10.5.

Real time spectrum analysis of signals obtained through lasso catheter during radiofrequency ablation of pulmonary vein was performed to determine the channel with dominant frequency. Threshold algorithm was used for signals which could be classified as type I and type II AF. Type III AF Signals which were highly fractionated or differentiated were evaluated for frequency content by performing Fast Fourier Transform. Data from Seven patients was collected and an episode of 180 ± 40 seconds was recorded and analyzed for each pulmonary vein that showed electrical activation. Frequency spectra for one second segment of signal for each channel were determined. The frequencies of channels were then compared to determine the channel with highest or dominant frequency. In most cases the frequency of a single channel varied erratically between 1 to 10 Hz for every subsequent one second segment which made DF detection among the channels unreliable and a single channel with dominant frequency could not be determined. A five second averaging for each channel did not produce a stable DF output and improvement was minimal. The erratic frequency behavior could be attributed to the spatial shift of micro- reentrant circuits or temporal variation in waveform over lap at the point of detection. To determine the DF more precisely either an increase in number of electrode or increase in time segment block for DF calculation is warranted. Increasing the time segment block will defeat the purpose of real time analysis thus an increase in number of electrode mapping the area of interest would be appropriate to resolve the issue.