The ability to maintain hydraulic continuity in the xylem is essential to supply leaves with the water that must be exchanged for carbon dioxide. The metastable nature of xylem sap causes this system to be inherently vulnerable to failure by rapid vaporization within the conduits. Much of the recent work on hydraulic architecture and cavitation has pursued the elusive mechanism behind apparent hydraulic recovery concurrent with tension in the bulk of the xylem, referred to as "novel refilling". An investigation into the dynamics of this behavior (Chapter 3) revealed two key artifacts that can produce the appearance of novel refilling when in fact no embolism (and therefore, no recovery) has occurred. A further implication of these artifacts is that plant xylem may be more robust against embolism than previously expected. In the absence of novel refilling, it becomes much harder to reconcile the extreme vulnerability reported for ring porous species. Studies of Robinia pseudoacacia (Chapter 4) address whether the artifacts illuminated in chapter 3 provide insight into the ongoing debate about the cavitation resistance of long-vesseled species and whether it is possible to accurately assess cavitation resistance in these species using the centrifuge method. Root pressure, as an alternative to novel refilling, provides plants with a means of reversing cavitation. Studies of Betula papyrifera (Chapter 5), however, show that recovery from embolism by root pressure is limited to early spring and point to an important role for water storage in fibers that minimizes xylem tensions and thus the risk of cavitation.

The main objective of this project is to design, construct and validate a portable prototype of a device that is capable of performing a test to accurately measure Capillary Refilling Time (CRT), and to analyze the results with defined parameters; force, area, pressure (compression) and time. This prototype is dedicated to study and evaluate CRT readouts for different pressure values, collected from healthy subjects.The presented prototype of this study is capable of producing skin compressing and to measure the refilling time of capillaries following this compression. This prototype introduces accuracy, mechanical reproducibility and controlling options for the applied pressure and compression time. The presented prototype is non-invasive, portable and it can be used to conduct more CRT tests and other capillary refilling studies.CRT measurement is done by calculating time interval starting from the first point when the applied pressure is released; ending with the recording point at the time when the concentration of red blood cells has reached the level of its pre-occlusion values.Based on the calculated CRT values and the number of iterations of the test in CRT tables, one can observe that given the same applied pressure value, CRT values do not significantly vary when the test is repetitively conducted on the same subject and on the same site.

The objective of this dissertation is the development of computer simulation-based models for the modeling of upper ionosphere, starting from the first principles. The models were validated by exact analytical benchmarks and are seen to be consistent with experimentally obtained results. This area of research has significant implications in the area of global communication. In addition, these models would lead to a better understanding of the physical processes taking place in the upper ionosphere.

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Presbyopia is the progressive decrease in accommodative ability with age, and it implies a major loss of visual function. Presbyopia is the only condition of the eye which affects everyone who lives beyond 50 years of age. As part of a joint effort, the Ophthalmic Biophysics Center at the Bascom Palmer Eye Institute and the Vision Cooperative Research Centre at the University of New South Wales, developed two different ex-vivo accommodation simulators (EVAS) to examine the mechanisms of accommodation and presbyopia, and to test and validate new ophthalmic surgical procedures such as lens refilling. The purpose of this thesis is to mechanically and optically calibrate the second generation instrument (EVASII), and to compare it to the first generation design (EVASI). To validate the optical measurements of EVASII, an optical calibration has been performed, yielding a lens power measurement system with a mean accuracy of ±0.56D. To enhance the optical capabilities and tissue dissection options, the mechanics of mounting the tissue has been improved by using magnetic mounts, and the mechanical calibration of EVASII, yielded a force measurement system with a mean uncertainty of ±0.81g Also, a comparison of EVASII and EVASI has been performed, showing that the results of the two systems are significantly different; however, both systems successfully simulate accommodation. Thus, general trends concerning efficacy and optimization of surgical procedures as well as age related accommodative changes can be compared for each individual system.

Well-defined silica supported bimetallic catalysts Pt100-x Pdx (where x is the molar ratio of Pd) are prepared by Surface Organometallic Chemistry (SOMC) via controlled decomposition of Pd2(allyl)2Cl2 on Pt/SiO2. For comparison purposes, Pt100-x Pdx bimetallic catalysts is also prepared by ion-exchange (IE). According to the results of STEM, XAS and H2 chemisorption, all bimetallic nanoparticles, prepared using neither SOMC nor IE, produce discrete formation of monometallic species (either Pt or Pd). Most catalysts exhibit a narrow particle size distribution with an average diameter ranging from 1 to 3 nm for samples prepared by IE and from 2 to 5 nm for the ones synthesized by SOMC. For all catalysts investigated in the present work, iso-butane reaction with hydrogen under differential conditions (conversions below 5%) leads to the formation of methane and propane (hydrogenolysis), n-butane (isomerization), and traces of iso-butylene (dehydrogenation). The total rate of reaction decreases with increasing the Pd loading for both catalysts series as a result of decreasing turnover rate (expressed as moles converted per total surface metal per second) of both isomerization and hydrogenolysis. In the case of Pt100-x Pdx(SOMC) catalysts, the results suggest a selective coverage of Pt (100) surface by a Pd layer, followed by a buildup of Pd overcoat onto a Pd layer assuming that each metal keeps its intrinsic catalytic properties. There is no mutual electronic charge transfer between the two metals (DFT). For the PtPd catalysts prepared by IE, the catalytic behavior cannot simply be explained by a surface coverage of highly active Pt metal by less active Pd (not observed), suggesting there is formation of a surface alloy between Pt and Pd collaborated by EXAFS and DFT. The catalytic results are explained by a simple structure activity relationship based on the previously proposed mechanism of C-H bond and C-C Bond activation and cleavage for iso-butane hydrogenolysis, isomerization, cracking and dehydrogenation.

This work is the final part of the Master of Science degree in Industrial Design Engineering towards Production Design, at Luleå University of Technology. This project has been conducted during the spring of 2017 at Alimak Hek. The task has been to analyze material handling, material presentation and why material shortages occur at the industrial hoists final assembly stations. To get an understanding of the system, interviews and observations were conducted. A literature study was carried out to find current knowledge and different solutions. To involve the workers in the process and to check if the problems were understood correctly a workshop was conducted. This was also an opportunity to discuss desired future state and ideas with the workers. Another way to look at potential solutions was through the benchmarkings. These were both conducted internally and at other companies where different solutions for material handling was studied.   The material in focus has been fastening material. This was stored in bins at racks. These racks were placed at the assembly stations and the two big racks have been the focus of this project. The problems at these storages has been that the refilling did not work as it was supposed to. The old system was an order list with which material could be ordered from the main storage at Alimak, this however is not used any more. The system of today is that the empty bins are collected and put on a pallet to be sent to the main storage for refilling. The problem with this is that the workers did not take the bins when they were empty but rather went to a different storage to look there. This meant that the material sometimes got totally emptied at all racks before the bins were sent to refilling. This made for urgent needs where workers had to go to the storage themselves to get something refilled. Another problem was that these storages were placed behind the fixed stations which made them hard to get to and see. The bins used in today’s system were not all marked the same way and an old system for numbering was still partly used. The bigger storages were divided so that one should have the stainless material and the other should have the galvanized/zinc-coated material. This together with the other aspects made it hard to know where the bins should be and sometimes all bins of one kind was put in the same rack.   To fix these problems different suggestions were made. The use of a two-bin system has been suggested because of its simplicity and the potential it has to avoid a lack of material to arise. The two racks of today should be combined into one and moved to a more visible place. This would make the refilling easier and reduce the need to search for material at different places. Two general layouts have been developed, and the open layout has been suggested to be implemented because of the accessibility it would bring to the system. The approximate size of the rack and bins needed have been put forward and different suggestion for order in the rack has been made. The marking of the bins and rack has also been discussed and this should be made distinct so it is easy to see and read.

This dissertation analyses various kinds of the orthographical exercises in the second grade of the primary school. The dissertation focuses on the question of orthography in the theoretical part, after that it focuses on a short view of orthography in the Czech history or its division into lexical, morphological and syntactical orthography. We find here a short description of the orthography and a view of orthographical's effects in the teaching of Czech language in the primary school or meeting with orthographical guides. The goal of the practical part of this dissertation is a deeper typological description of these exercises, we will primarily focus on examples of rewriting, orthographical analysis, refilling and alternating exercises and dictations.