A quantum crystallographic approach to study properties of molecules in crystals

In this dissertation, the behaviour of atoms, bonds, functional groups and molecules in vacuo but especially also in the crystal is studied using quantum crystallographic methods. The goal is to deepen the understanding of the properties of these building blocks as well as of the interactions among them, because good comprehension of the microscopic units and their interplay also enables us to explain the macroscopic properties of crystals. The first part (chapters 1-3) and second part (chapter 4) of this dissertation contain theoretical introductions about quantum crystallography. On the one hand, this expression contains the termquantum referring to quantumchemistry. Therefore, the very first chapter gives a brief overview about this field. The second chapter addresses different options to partition quantum chemical entities, such as the electron density or the bonding energy, into their components. On the other hand, quantumcrystallography consists obviously of the crystallographic part and chapter 3 covers these aspects focusing predominantly on X-ray diffraction. A more detailed introduction to quantum crystallography itself is presented in the second part (chapter 4). The third part (chapters 5-9) starts with an overview of the goals of this work followed by the results organized in four chapters. The goal is to deepen the understanding of properties of crystals by theoretically analysing their building block. It is for example studied how electrons and orbitals rearrange due to the electric field in a crystal or how high pressure leads to the formation of new bonds. Ultimately, these findings shall help to rationally design materials with desired properties such as high refractive index or semiconductivity.Mithilfe quantenkristallografischer Methoden werden Atome, Bindungen, funktionellen Gruppen und Moleküle in vacuo aber vor allem auch in Kristallen untersucht. Das Ziel ist es die Eigenschaften dieser Bestandteile zu verstehen und wie sie miteinander interagieren. Das Verständnis der Verhaltensweise der einzelnen Bausteine sowie deren Zusammenspiel auf mikroskopischer Ebene kann auch die makroskopischen Eigenschaften von Kristallen erklären. Der erste Teil dieser Doktorarbeit (Kapitel 1-3) beinhaltet eine theoretische Einleitung in die verschiedenen Bereiche der Quantenkristallografie. Wie der Name Quantenkristallografie besagt, besteht diese zum einen aus dem quantenchemischen Teil, weswegen das erste Kapitel eine kurze Einführung in die Quantenchemie gibt. Das zweite Kapitel widmet sich den verschiedenen Möglichkeiten quantenchemische Grössen wie zum Beispiel die Elektronendichte oder Bindungsenergien in Einzelteile zu zerlegen. Zum anderen trägt der kristallografische Teil zur Quantenkristallografie bei. Kapitel drei besteht daher aus einem kurzen Überblick über die Kristallografie mit Fokus auf der Röntgenbeugung. Anschliessend folgt im zweiten Teil (Kapitel 4) eine ausführlichere Einleitung in die Quantenkristallografie selbst. Der dritte Teil (Kapitel 5-9) beginnt mit einer kurzen Übersicht über die Ziele dieser Arbeit worauf die Resultate, gegliedert in vier verschiedene Kapitel, folgen. Das Ziel dieser Arbeit ist es die Eigenschaften von Kristallen besser zu verstehen, indem man ihre Einzelteile theoretisch analysiert und mit verschiedenen Methoden rationalisiert. Beispielsweise wird untersucht wie sich Elektronen und Orbitale aufgrund des elektrischen Feldes in Kristallen neu anordnen oder wie unter hohem Druck Bindungen neu geformt werden. Schlussendlich können all diese Erkenntnisse helfen, Materialien mit spezifischen gewünschten Eigenschaften herzustellen.Les atomes, les liaisons entre eux, les groupes fonctionnels et les molécules sont examinés en utilisant des méthodes de la cristallographie quantique. Le but est de comprendre les propriétés de ces composants et comment ils interagissent in vacuo mais surtout aussi dans les cristaux. En comprenant leurs caractéristiques et interactions au niveau microscopique, on peut aussi rationaliser les propriétés macroscopiques des cristaux. La première partie (chapitres 1-3) de cette thèse de doctorat contient une introduction brève à la cristallographie quantique. Comme le noml’indique, ce domaine de recherche est composé de la chimie quantique et la cristallographie. Pour cette raison le premier chapitre donne une introduction à la chimie quantique. Le deuxième chapitre présente quelques méthodes de décomposition des quantités de la chimie quantique comme la densité électronique ou l’énergie de liaison. Le troisième chapitre couvre la partie cristallographique. Ensuite dans la deuxième partie (chapitre 4) une introduction plus détaillée sur la cristallographie quantique elle-même est donnée. La troisième partie (chapitres 5-9) commence par un aperçu des objectives de cette dissertation suivis des résultats structurés en quatre chapitres. Le but est de comprendre les propriétés des cristaux en analysant leurs building blocks avec différentes méthodes théoriques. Il était par example examiné comment les électrons et les orbitales se réorganisent dans un cristal à cause du champ électrique ou comment des nouvelles liaisons sont formées sous pression. Finalement on peut utiliser ces conclusions pour modeler des matériaux avec des propriétés désirées

Endangered by Sprawl: How Runaway Development Threatens America's Wildlife

Estimates the growth of land consumption in metropolitan areas over the next 25 years, investigates locally implemented strategies to protect natural lands from overdevelopment, and offers "smart growth" as an option for reducing suburban sprawl

Disconnected: Poverty, Water Supply and Development in Jakarta, Indonesia

human development, water, sanitation

The Regional Response to Federal Funding for Bicycle and Pedestrian Projects

Examines the efficacy of federal funding for non-motorized modes of transportation based on funding patterns across metropolitan regions, case studies of policies and projects, and an analysis of the funding's impact on bicycling and walking behavior

Bioengineering of Fetal Skin: Differentiation of Amniotic Fluid Stem Cells into Keratinocytes

PURPOSE Open fetal spina bifida repair has become a novel clinical standard of care. In very large spina bifida lesions, the skin defect cannot be covered primarily, asking for alternative solutions. We hypothesize that amniotic fluid stem cells (AFSC) could be differentiated into keratinocytes that could then be used to bioengineer autologous skin usable for in utero back coverage. METHODS To obtain human AFSC, amniotic fluid samples obtained from fetal surgeries were subjected to immunoselection for c-kit. C-kit-positive samples and controls were cultured with the additives morphogenetic protein 4 and vitamin C to induce differentiation towards keratinocytes. This process was monitored by measuring the expression of K8 and K14 via immunohistochemical staining, flow cytometry, and polymerase chain reaction. RESULTS After immunoselection and expansion, most cells were positive for K8, but none for K14. After completion of the differentiation protocol, cell colonies with keratinocyte-like appearance could be observed, but cells remained positive for K8 and negative for K14, indicating failed differentiation into keratinocytes. CONCLUSIONS Culturing of keratinocyte-like cells from AFSC, harvested intraoperatively, was not feasible in this setting. The reasons for failure must be investigated and eliminated, as bioengineering of fetal skin for clinical use during fetal surgery for spina bifida remains an attractive goal

Orthorexia nervosa: real construct or newest social trend?

Title from PDF of title page, viewed on July 25, 2011Dissertation advisor: Lisa TerreVitaIncludes bibliographical references (p. 94-110)Thesis (Ph.D.)--Dept. of Psychology. University of Missouri--Kansas City, 2011Despite a plethora of anecdotal evidence, there are very few empirical studies on orthorexia nervosa, which has been described as an obsession with proper nutrition and the consumption of healthy food. Accordingly, the purpose of this study was to begin to explore the epidemiological contours of orthorexia nervosa in an American college student sample and the validity of orthorexia nervosa as a psychological construct. Specifically, this study evaluated the potential overlap between orthorexia nervosa and existing DSM disorders to which it has been compared in the emerging literature. Data included self-reported responses to paper and pencil questionnaires from 163 study participants. The results of this study did not confirm risk factors identified by the few previous ON studies. In addition, the findings from this study indicated that ON shares important characteristics with established eating disorders. However, more research is needed to determine if ON is a distinct construct, involves constructs not assessed in this study, or simply a societal trend.Introduction -- Literature review -- Methodology -- Results -- Discussion -- Appendix A. Comparison of diagnostic validity of on to existing disorders -- Appendix B. Study information sheet -- Appendix C. Demographics questionnaire -- Appendix D. Conceptual representation of regression analysi

Etude des plaques de Peyer de l'intestin du souriceau nouveau-né comme voie possible de pénétration du virus du cancer mammaire de la souris (MMTV)

Peer reviewe

Back seat driving: hindlimb corticospinal neurons assume forelimb control following ischaemic stroke

Whereas large injuries to the brain lead to considerable irreversible functional impairments, smaller strokes or traumatic lesions are often associated with good recovery. This recovery occurs spontaneously, and there is ample evidence from preclinical studies to suggest that adjacent undamaged areas (also known as peri-infarct regions) of the cortex ‘take over' control of the disrupted functions. In rodents, sprouting of axons and dendrites has been observed in this region following stroke, while reduced inhibition from horizontal or callosal connections, or plastic changes in subcortical connections, could also occur. The exact mechanisms underlying functional recovery after small- to medium-sized strokes remain undetermined but are of utmost importance for understanding the human situation and for designing effective treatments and rehabilitation strategies. In the present study, we selectively destroyed large parts of the forelimb motor and premotor cortex of adult rats with an ischaemic injury. A behavioural test requiring highly skilled, cortically controlled forelimb movements showed that some animals recovered well from this lesion whereas others did not. To investigate the reasons behind these differences, we used anterograde and retrograde tracing techniques and intracortical microstimulation. Retrograde tracing from the cervical spinal cord showed a correlation between the number of cervically projecting corticospinal neurons present in the hindlimb sensory-motor cortex and good behavioural recovery. Anterograde tracing from the hindlimb sensory-motor cortex also showed a positive correlation between the degree of functional recovery and the sprouting of neurons from this region into the cervical spinal cord. Finally, intracortical microstimulation confirmed the positive correlation between rewiring of the hindlimb sensory-motor cortex and the degree of forelimb motor recovery. In conclusion, these experiments suggest that following stroke to the forelimb motor cortex, cells in the hindlimb sensory-motor area reorganize and become functionally connected to the cervical spinal cord. These new connections, probably in collaboration with surviving forelimb neurons and more complex indirect connections via the brainstem, play an important role for the recovery of cortically controlled behaviours like skilled forelimb reachin

Balance control in pirouettes – what role does spotting play?

Rotations around the vertical axis are among the most often-performed dance movements. Especially in ballet, pirouettes take a prominent place in the movement vocabulary. However, evidence on balance control and coordination during pirouettes is scarce. So far, no studies have addressed the influence of the fundamental spotting technique on balance in pirouettes. Therefore, the aim of this presentation is to summarise findings from two different studies on balance control and the coordination of spotting in pirouettes and continuous rotations. Study A tested 24 intermediate ballet dancers for postural stability after turning 14 consecutive rotations either actively or passively on a rotating chair. In both conditions, participants turned once while adopting the spotting technique and once without spotting. Before and after the rotations, Centre-of-Pressure (COP) displacement in quiet stance was measured on a force plate and perception of vertigo after-effect was measured by self-assessment (Keshavarz & Hecht, 2011). Conditions were compared with repeated-measures ANOVA. Study B was conducted with eight intermediate dancers who performed double pirouettes with and without the spotting technique. Whole-body movement was measured with a three-dimensional motion capture system and COP displacement with a force plate. The following balance measures were calculated: topple angle, instantaneous axis, and displacement of the foot marker. The following spotting measures were calculated: duration of head towards front, and head-trunk dissociation. Study A showed that balance after turning with the spotting technique was better than turning without spotting (p=.047). It thus seems that spotting helps balance control after rotations. In study B, we could show that spotting also helps balance control during rotations (topple angle with spotting is smaller (M=5.8°, SD=1.1°) than while turning without spotting (M=7.1°, SD=1.2°; p>.001). Besides discussing the results of our studies in more detail, we will present the advantages and disadvantages of different performance measure in pirouettes. Valid, dance-specific measures are crucial to allow for the comparison and progress of studies in the field of dance science and further, to advance the understanding of the role of spotting in whole body rotations. This research brings novel insights to the methods for quantifying the complex movements of dance, ultimately to improve dance training and technique. References: Keshavarz, B., & Hecht, H. (2011). Validating an efficient method to quantify motion sickness. Human factors, 53(4), 415–426