Annotation Following work deals with the design proposal of the screw drive vehicle designed for the rescue and evacuation from the places which are unavailable to reach with usual vehicles. The intention was to diversify the current drive to design an innovative concept which will be in line with today‘s technological knowledge and modern trends. The main objective of the thesis is to solve the design and the shape of the vehicle which implements the requirements for an emergency car not only in terms of the appearance, but also in the way of functionality and variability of the interior. The thesis is divided into three general parts. The first one includes the historical development, the analysis and the description of technologies. The second part deals with the design, options and their ergonomic and technical solutions. In the last part is the end-point analysis of the proposal.

This master's thesis includes theoretical analysis of characteristics of a centrifugal pump, conditions of stability of Y(Q) characteristic, calculation of characteristics ßč(ns), modifications leading to stabilization of a spiral body and a runner, a design of the spiral, the runner and follow-up computation in Fluent program.

Reliable signal transmission among cells is important for long-range coordination. While higher organisms have designated structures for signal transmission, such as axons, it remains unclear how simpler communities of cells are organized to relay signals. Furthermore, many biological systems exhibit spatial heterogeneity, which can interrupt signal propagation. In this thesis, we investigate this problem by modeling the spatial organization and dynamics of electrochemical signaling, and we compare our results to experiments from our collaborators on Bacillus subtilis bacterial biofilms. The experiments show that only a fraction of cells participates in signal propagation and that these cells are spatially clustered with a size distribution that follows a power-law decay. These observations suggest that the fraction of participating cells is just at the tipping point between a disconnected and a fully connected conduit for signal transmission. We utilize percolation theory and a minimal FitzHugh-Nagumo-type excitable dynamics model to test this hypothesis, and genetically modified biofilms with altered structure and dynamics to validate our modeling. Our results suggest that the biofilm is organized near the critical percolation point in order to negotiate the benefit and cost of long-range signal transmission. Then, more detailed experiments show that the participation probability is correlated from cell to cell and varies in space. We use these observations to develop an enhanced percolation model, and show using simulations and a renormalization argument that the main conclusions are unaffected by these features. Finally, we use our dynamic model to investigate the effects of heterogeneity beyond the radial wave regime and into the spiral wave regime. We find that spatial correlations in the heterogeneity promote or suppress spiraling depending on the parameters, a surprising feature that we explain by demonstrating that these spirals form by distinct mechanisms. We characterize the dependence of the spiral period on the heterogeneity using techniques from percolation theory. Taken together, our results reveal that the spatial structure of cell-to-cell heterogeneity can have important consequences for signal propagation in cellular communities.<br>

L’emphysème pulmonaire est, avec la bronchite chronique à laquelle il est généralement associé, une bronchopathie chronique obstructive (BPCO). Ce groupe de maladie a été la sixième cause de mortalité au monde en 1990 et pourrait devenir la troisième en 2020.L’emphysème pulmonaire est défini par un élargissement anormal et permanent des espaces aériens en amont des bronchioles terminales avec destruction des parois alvéolaires sans fibrose évidente. Compte tenu de cette définition, son diagnostic devrait idéalement être basé sur l’histopathologie. Cependant, en pratique clinique, si les EFR sont à la base de la définition de la BPCO, elles ne suffisent pas au diagnostic de l’emphysème pulmonaire.<p><p>La tomodensitométrie (TDM) est une méthode diagnostique d’obtention in vivo de coupes anatomiques qui, formées de milliers de pixels, en font la méthode morphologique la plus précise pour investiguer la structure pulmonaire. Si la juxtaposition de ces pixels – dont la tonalité de gris est fonction de l’atténuation – est à la base de l’image TDM, la même information peut être représentée par la distribution de fréquence de ces atténuations. En présence d’emphysème, la destruction du tissu pulmonaire (et la plus grande proportion d’air) déterminent le déplacement de cette distribution vers les atténuations plus négatives. Plusieurs index TDM dérivés de cette distribution – notamment l’atténuation moyenne, la surface pulmonaire occupée par des valeurs d’atténuation inférieures à un seuil, un percentile particulier de la distribution – sont de possibles mesures de l’étendue de l’emphysème pulmonaire. L’émergence de la technique hélicoïdale, permettant notamment d’explorer tout le parenchyme pulmonaire en une seule apnée, justifie de déterminer les seuils et percentiles adéquats par comparaison à une mesure histologique de référence.<p><p>Au cours de nos études, nous avons montré que les index TDM dérivés de la distribution de fréquence d’atténuation tels que les surfaces relatives de poumon occupées par les coefficients d’atténuation inférieures à -960 UH (RA960) ou -970 UH (RA970) et le premier percentile (p1) sont les index les plus appropriés. En revanche, toujours sur base de comparaisons histo-morphométriques, d’autre index qui reflètent la géométrie des espaces emphysémateux – tels que la distribution de la taille des groupes de pixels adjacents occupés par des coefficients d’atténuation inférieurs à un seuil ou à un percentile – ne sont pas des index valables.<p><p>La dose d’irradiation peut être abaissée à 20 mAs effectifs. Cette réduction est particulièrement appropriée dans une pathologie susceptible de concerner des patients jeunes et l’objet d’examens répétés. Cependant, la dose d’irradiation influençant ces index, elle doit être maintenue constante au cours de suivis longitudinaux.<p><p>En TDM multi-coupes, ces index sont les plus appropriés quelque soit l’épaisseur des coupes. Cependant, cette épaisseur influençant ces index, elle doit aussi être maintenue constante au cours de suivis longitudinaux.<p><p>L’inspiration incomplète induit une sous-estimation statistiquement significative mais cliniquement insignifiante de l’étendue de l’emphysème pulmonaire. La destruction du tissu pulmonaire et l’hyperinflation ont des influences séparées sur les index TDM, faisant recommander leur ajustement aux valeurs prédites de la CPT.<p><p> / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished

The foundational hypothesis to this study is that congregations which have a healthy perception and a greater understanding of conflict will develop more effective responses to conflict that will translate into more effective conflict resolution and reconciliation. The process and sustainability of the development of a missional church, the context of the study, is pregnant with potential conflict. Untamed conflict has the propensity to retard, jeopardise or even destroy the development of a missional church. When conflict arises, it must be understood and dealt with theologically. The inherent problem is that conflict appears to be neither understood nor appreciated sociologically and theologically. This knowledge and praxis vacuum has the potential for conflict to translate into inappropriate or ineffective responses that do not always make for effective resolution and reconciliation. The research focuses mainly on an empirical study based on the four practical theological questions of Osmer (2008). Participants for this study were randomly selected from specific sectors of Methodist congregations in the wider Pretoria area. The research explores congregants’ perceptions, understanding and views of conflict; their responses to conflict; and some felt and observed outcomes of conflict. The presupposition is that the development of the local missional church would be more effective and efficient when the management and process of conflict resolution and reconciliation are well led and well managed. This study confirmed that conflict, despite its normalcy and necessity, carries a negative undertone and is mostly avoided in congregations. This is compounded by the evidence that there is little, if any, theological or scriptural understanding of conflict. There is also no indication that churches intentionally and purposefully educate their members to appreciate and understand conflict. In so doing, churches are harming their innate calling as the glory and manifestation of God’s divine grace through faith communities for the transformation of all peoples. Yet, the church understands the dangers of unhealthy conflict, and on occasion even expects conflict to arise, although deeming it inappropriate. Practical theological discernment is sought as to why this may be so and remedial action is proposed to address the problem of conflict within congregations. / Thesis (PhD)--University of Pretoria, 2017. / Practical Theology / PhD / Unrestricted

The objective of this work is to develop a near-infrared laser device capable of emitting orbital angular momentum (OAM) light. The prototyped device must be suitable for compact, energy-saving optical communication applications. Integrated OAM lasers will revolutionize high-capacity data transmission over any telecommuni- cation network environment, as OAM light can be guided and transmitted through kilometers of optical fibers and propagated in free space and underwater. Several methods for generating OAM light employing various complex monolithic and hybrid integration methods have been demonstrated. In this work, microscale integrated spiral phase plates (SPPs) are chosen to convert the laser beam output into an OAM mode. The concept and design fundamentals of SPPs are discussed, followed by the SPP fabrication process and their implementation in a high-speed communication setup and then integration with a semiconductor laser. SPPs are fabricated by a novel direct laser writing that provides the possibility to rapidly prototype 3D photonic structures via a two-photon polymerization pro- cess. After fabrication, SPPs are used in a fine-tuned free-space optical experimental setup that requires high-precision intercomponent alignment to test the high-speed OAM communication system and analyze the quality of OAM modes, resulting in high-purity OAM signals at data rates up to 1.8 Gbit/s – limited by the avalanche photodetector (APD) frequency response. The fabricated 20-μm-diameter SPPs were the smallest reported in the literature to date for optical characterization. A proof-of-concept monolithic light-emitting array, as a highly integrated OAM laser source, is further proposed for telecommunications and other applications. SPP-integrated 940-nm vertical-cavity surface-emitting laser (VCSEL) array chips that are relatively low-cost, have a small footprint, and are manufacturable in high volumes are developed. SPPs with topological charge modulus values from 1 to 3 are fabricated on the VCSEL arrays, demonstrating OAM modal purities up to ∼65%. The experimentally evaluated data rates in the OAM setup showed consistently sta- ble links up to 2.0 Gbit/s with a bit error ratio of ∼ 1.6 × 10−8 (APD-limited). The challenges of SPP-laser integration are summarized, with the conclusion that the widespread adoption of OAM is limited by the availability of practical integrated solutions for OAM generation and detection.

Stationary spiral inserts can effectively enhance heat transfer and temperature blending in the heat convection systems. In this paper, the impact of the segment length on the performance of a stationary insert is studied for flow Re numbers from ~80 to ~7900 through numerical simulation of heat transfer in streams of cold and hot gases flowing across it. The segment length to width ratio is from 1.11 to 2.33. The temperature of the studied gas is from 300 K to 1300 K. It is shown that the insert with variable segment length is more effective in temperature blending for two compressible streams compared with an insert with constant segment length, especially for low-Re-number turbulent flows.

Embryogenesis is one of the most delicate biological processes which requires precise control in various levels, including molecular distribution and gene expression, cellular orientation and specification, and tissue dynamics giving rise to proper morphology. The diverse animal morphology can be resulted from the difference during early embryonic cleavages. Spiral cleavage is a conserved embryonic patterning strategy used in the majority of the animal clade Spiralia. The specific cell positioning during cell division and quadrant-based clonal domain formation make the embryos with the blastomeres orientated in a spiral manner when viewing from the animal pole. Although spiral cleavage is conserved in many phyla, the detailed cellular, molecular and biophysical mechanisms for this left-right symmetry breaking event remain unclear. Here I studied the early development of the prototypic annelid spiral-cleaver Platynereis dumerilii, which performs two unequal embryonic cleavages followed by the first dextral spiral cleavages, and compared the mechanisms to other spiralians or to other cleavage types. First, I described the morphology of each cell cycle from the zygote until 64-cell stage by imaging the fluorescently labeled fixed embryos. Second, with mRNA injection, whole-embryo live-imaging with Selective Plane Illumination Microscopy (SPIM), and in silico cell tracking, I monitored these cleavages in 4-D, constructed the early cell lineages, and revealed the subtle asynchrony of the four quartets. Third, together with the spindle inclination angle measurement, I discovered the leading role of the D macromere during P. dumerilii spiral cleavage. I also confirmed that the dextral micromere orientation is neither affected by the eggshell nor the presence of all the neighbor macromeres, suggesting that this cellular property may be achieved by cell autonomous molecular mechanisms. In order to quantify the candidate cytoskeletal dynamics during spiral cleavage, I optimized the construction of the injected mRNAs and the injection protocol to achieve the highest translational level of the fluorescent protein within a given developmental time. Beside mRNA injection, I also established a protein expression and injection protocol for P. dumerilii protein injection in order to visualize the target gene as early as possible. Both techniques didn’t dramatically influence embryogenesis and allow for quantification of the protein dynamics. With these strategies, I discovered and measured the chiral counter rotational flow of cortical actomyosin in each spiral cleavage and revealed that it’s present in the first two spiral cleavages, especially of the macromeres. The biophysical force generated by actomyosin contributes in the cell deformation and spindle inclination, resulting in proper dextral micromere positioning, during the first spiral cleavage, confirmed by the chemical treatment to the P. dumerilii embryos. The asymmetric actomyosin distribution, nuclei migration, and the change of the cell axes during cytokinesis in the macromeres also suggests that the macromeres may play critical roles to lead spiral cleavage. This work is built on the knowledge of the spiral cleavage machinery and has extended it in multiple dimensions. The detailed phase-by-phase description of each cleavage increases the information of P. dumerilii embryogenesis. The established labeling and imaging techniques in this thesis are the important basis for investigation and comparisons of different spiralian development in the future. More broadly, the discovery of actomyosin dynamics shows conservation to the left-right symmetry breaking events of the animals which does not belong to Spiralia. These together bring insights to a global evolutionary speculation: a conserved mechanical force generation pathway, tuned by the upstream molecular signals, may be the key of the miscellaneous cleavage types, resulting in the astonishing variety of embryo patterning.

Introduction: The aim of this study was to evaluate the frequency and amount of Ca(OH)2 extrusion in relation to the intracanal delivery technique, apical foramen size, and depth of placement. Methods: Standardized training blocks with j-shaped canals were used (n=64); half of the simulated canals were shaped to apical size #35(.06 taper) and the remaining 32 to #45(.06). The frequency and extent of Ca(OH)2 extrusion were measured relative to apical taper, the depth of insertion, and whether syringe or spiral filler was used. Blocks were immersed in pH-sensitive gel and observed for color change. The visible extent of extrusion, indicated by color change, was determined as area and expressed in mm2. Results: Extrusion of Ca(OH)2 occurred in 48/64 of the samples. At 3mm from the canal terminus, the device type had a significant effect on the frequency of extrusion, with syringe placement causing extrusion significantly (p<0.01) more frequently, irrespective of device size. Amounts of extrusion were significantly larger at 2mm short of the canal terminus (median 27.44mm2, IQR 10.02), compared to 3mm distance (median 19.69mm2, IQR 25.07; p<0.0001). Analyzed separately at 2 and 3mm distance, respectively, there was significantly more extrusion with placement using a syringe size #35 compared to spiral filler size #45. Conclusions: Considering the limits of the in vitro experimental design, a spiral filler at 500rpm, placed 3mm short of the apex found to minimize extrusion of Ca(OH)2 placed in root canals.

The main aim of the diploma thesis is reconstruction of Viskafors railway station and its adjacent track at KM146+ 800 - 145+ 700 so as to satisfy the current traffic and at the same time the legislation is met. The tracks geometry and turnouts in the station was solved according to Swedish and Czech standards and conventions. As part of the reconstruction, the connection of the service track was resolved from the north side.