DESIGN OF A BAKERY IN ALEXANDRIA, VIRGINIA Through the evolution of a baker's practices, we can understand the transitions of matter between bread, body and building. The food soil waste system of the bakery becomes an evolutionary process of recovery, remediation, restoration, replenishment, and reuse. / Master of Architecture / Through the evolution of a baker’s practices, we can understand the transitions of matter between bread, body and building. The food soil waste system of the bakery becomes an evolutionary process of recovery, remediation, restoration, replenishment, and reuse. “There is a crime here that goes beyond denunciation. There is a sorrow here that weeping cannot symbolize. There is a failure here that topples all our success.” (Steinbeck, 2008) Learning from the skies above and ground beneath, I propose a horizon that binds the two in a closed loop system. As a baker combines earth, water, wind, and fire to transform dough into bread, the bakery is designed to knead these same elements together to create a harmonious relationship between man and nature.

In dieser Masterthese werden Zwischenergebnisse einer dreijährigen Studie vorgestellt, die eine resektive mit einer regenerativen Methode zur Behandlung von Periimplantitis vergleicht. Derzeit liegen Daten über einen sechsmonatigen Beobachtungszeitraum für vier Patienten in der (resektiven) Kontrollgruppe und fünf in der (regenerativen) Testgruppe vor. Patienten beider Gruppen mit einer extensiven Parodontitisvorgeschichte präsentieren sich in der Regel mit größeren Sondierungstiefen. Größere Sondiertiefen zu Beginn der Behandlung zeigen eine Tendenz zu schlechteren Ergebnissen im Verlauf der Beobachtungsphase, wobei der kausale Zusammenhang dazu in einer ähnlichen Pathogenese der Parodontitis und des schlechten Periimplantitisbehandlungserfolges liegen kann, die durch dieselben Risikofaktoren beeinflusst wird (Mundhygiene, genetische Faktoren, Mundflora etc.). Die Wundabdeckung nach der Augmentation scheint eine noch bedeutendere Rolle für die Prognose zu spielen als die Parodontitisvorgeschichte. Wund- und Nahtdehiszenzen sind die häufigsten Komplikationen in der Testgruppe. Bei einem Patienten der Testgruppe entwickelte sich aufgrund einer Wunddehiszenz eine fulminante Infektion und Entzündung, die letztlich zum Verlust des Implantates führte. Sondiertiefen und PES der Testgruppe zeigen drei und sechs Monate nach der Behandlung eine deutliche Verbesserung, wobei der Unterschied in den durchschnittlichen Sondiertiefen zwischen Behandlungsbeginn und drei oder sechs Monate danach z. T. statistisch signifikant war. In der Kontrollgruppe veränderten sich dagegen die Sondiertiefen und der PES nach der Behandlung nicht. Insgesamt sind die Ergebnisse vielversprechend mit deutlichen Verbesserungen des BOP und der Sondiertiefe, jedoch ist der Erfolg der Augmentation von der Operationstechnik abhängig. Für die Beurteilung eines Langzeiterfolges ist es derzeit noch zu früh. / This master thesis presents intermediate results of a three-year study that compares a resective with a regenerative method for the treatment of peri-implantitis. Currently, data are available over a six-month observation period for four patients in the (resective) control group and five in the (regenerative) test group. Patients in both groups with an extensive history of peri-ondotitis present usually with larger probing depths. Larger probing depths at the beginning of treatment show a tendency to result in worse outcomes during the monitoring phase. The causal relationship of this could be a similar pathogenesis of both peri-odontitis and a unfavorable outcome of the peri-implantitis treatment, which is influenced by the same risk factors (oral hygiene, genetic factors, oral flora, etc.). The wound covering after augmentation seems to play an even greater role for the prognosis compared to a history of peri-ondotitis. Wound and suture dehiscence are the most common complication in the test group. In one patient of the test group, a fulminant infection and inflammation developed as a result of wound dehiscence that ultimately led to the loss of the implant. Probing depths and PES in the test group at three and six months after treatment showed a significant improvement compared to the baseline before the treatment. This difference in the average probing depths between baseline and three or six months thereafter was in part statistically significant. In the control group, however, the probing depths and the PES did not change after treatment. Overall, the results are promising with significant improvements in the BOP and the probing depth, but the success of the augmentation depends on the surgical technique. At this point it is still to early to assess long-term success.

Despite a comprehensive mapping of the Parkinson's disease (PD)-related mRNA and protein leucine-rich repeat kinase 2 (LRRK2) in the mammalian brain, its physiological function in healthy individuals remains enigmatic. Based on its structural features and kinase properties, LRRK2 may interact with other proteins involved in signalling pathways. Here, we show a widespread LRRK2 mRNA and/or protein expression in expanded or differentiated human mesencephalic neural progenitor cells (hmNPCs) and in post-mortem substantia nigra PD patients. Using small interfering RNA duplexes targeting LRRK2 in hmNPCs following their differentiation into glia and neurons, we observed a reduced number of dopaminergic neurons due to apoptosis in LRRK2 knockdown samples. LRRK2-deficient hmNPCs exhibited elevated cell cycle- and cell death-related markers. In conclusion, a reduction of LRRK2 expression in hmNPCs severely impaired dopaminergic differentiation and/or survival of dopaminergic neurons most likely via preserving or reactivating the cell cycle.

Embryonic stem (ES) cells, which possess proliferating and differentiating abilities, are a potential source of cells for regenerative medicine. Nowadays, the challenge in using ES cells for developmental biology and regenerative medicine has been to direct the wide differentiation potential towards the derivation of a specific cell fate. This study is aimed to establish a simple and efficient method to derive ES cells into neural lineage cells and examine the safety and efficacy of derived cells in a mouse ischemic stroke model. To explore the underlying mechanisms responsible for lineage commitment of stem cells, Notch signaling and serotonin responses are also studied. / In a non-contact coculture system, mouse ES cells (D3 and E14TG2a) were cocultured with the stromal cells MS5 for eight days. On the other hand, human ES cells (H9 and H14) were directly cocultured with MS5 in a contact manner for two weeks. Derived cells were further propagated in a serum-free medium and selected subsequently in a differentiating medium. The cell viability, numbers, phenotypes and lineage-specific gene expression profile were evaluated at stages of induction, propagation and selection. / In vivo, behavioral assessments of ischemic mice after transplantation of mouse ES cell derivatives revealed a significant improvement in spatial learning and memory ability as compared to ischemic mice without cell therapy. Histology of brain sections of transplanted mice demonstrated the migration of BrdU+ cells to the CA1 region of the hippocampus, which was evident of both an increase of pyramidal neuron density and normalized morphology. Teratoma development was found in one out of 17 transplanted mice. / MS5 was noted to express genes encoding neurotrophins and neuroprotective factors. Functional tests showed that MS5 exerted neurotrophism on neuroblastoma cell lines (SK-N-AS, SH-SY5Y, and SK-N-MC) and ES cells. The numbers of viable cells and the proportion of neural subtypes derived from ES cells at three stages of the culture system were significantly higher than those of the control cultures without MS5 induction, respectively. MS5 cocultures generate a relatively higher yield of neural lineage cells but select against the mesodermal and endodermal lineage derivatives. Together with non-contact MS5 coculture, serotonin could further increase the proportion of neural precursors and accelerate maturation of neural progenitor cells in a synergistic manner. During the induction phase with non-contact MS5 coculture, the Notch inhibitor could significantly decrease the number of derived neural precursors and instigate non-neural differentiation. With the supplement of the Notch inhibitor, serotonin could neither promote the expression of neuroectodermal genes nor enhance the proportion of neural precursors in MS5-cocultured ES cells. Notably, in the propagation of undifferentiated human ES cells, Notch signaling was also found to play an active role in maintaining cell survival. / The Notch inhibitor (gamma-secretase inhibitor) and serotonin were supplemented into induction cultures to investigate the roles of Notch signaling and the neurotransmitter serotonin in neural differentiation. For in vivo study, mouse ES cell-derived cells were labeled with BrdU and implanted onto the caudate putamens of mice having undergone transient occlusion of bilateral common carotid arteries and reperfusion to induce cerebral ischemia. Spatial learning and memory ability of transplanted mice were assessed in a water maze system. Histological assessment was also conducted on brain sections of mice three weeks post transplant to examine the migration and homing of implanted cells. / This study describes a simple and efficient differentiation protocol to derive mouse ES cells and human ES cells into neural lineage cells. Derived cells appear to significantly improve cognitive functions in a mouse ischemic stroke model. Data of the study suggest that MS5 cells may exert a neurotrophic effect on ES cells. With MS5 coculture, serotonin synergistically promotes neural commitment and facilitates maturation of derived neural precursors in ES cell cultures. In contact coculture with MS5, Notch signaling is shown to play a role in the directed neural differentiation of human ES cells, whereas in maintenance culture, Notch signaling is also important to cell survival of human ES cells. Thus, Notch signaling through cell-cell interaction may explain, at least partially, the difference between mouse ES cells and human ES cells in cell growth ability when seeded at low cell densities. / Yang Tao. / Adviser: Ho Keung Ng. / Source: Dissertation Abstracts International, Volume: 70-09, Section: B, page: . / Thesis submitted in: November 2008. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 161-194). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

High-peak power laser systems are defined along with a brief introduction of the technology used in their development and application to the project. A review of concepts surrounding optical pulses, focusing on the particular phenomena involved with the ultrafast, follows. Numerical models involving optical pulses are introduced and verified. An extensive description of the laser system is presented, including models used in its design. Data verifying the correct operation of the laser system is presented and interpreted. A dispersion compensation system, including a function model, is introduced, and its application to the laser system is analyzed. An introduction to pulse characterization techniques is presented followed by the design and verification of two different characterization devices. Experiments utlizing the dispersion compensation system and pulse characterization devices are presented and the results are interpreted. Conclusions are made regarding the performance of the laser system models and pulse characterization devices, along with suggested improvements for each. The results of the experiments are discussed including suggestions for future work.

High-peak power laser systems are defined along with a brief introduction of the technology used in their development and application to the project. A review of concepts surrounding optical pulses, focusing on the particular phenomena involved with the ultrafast, follows. Numerical models involving optical pulses are introduced and verified. An extensive description of the laser system is presented, including models used in its design. Data verifying the correct operation of the laser system is presented and interpreted. A dispersion compensation system, including a function model, is introduced, and its application to the laser system is analyzed. An introduction to pulse characterization techniques is presented followed by the design and verification of two different characterization devices. Experiments utlizing the dispersion compensation system and pulse characterization devices are presented and the results are interpreted. Conclusions are made regarding the performance of the laser system models and pulse characterization devices, along with suggested improvements for each. The results of the experiments are discussed including suggestions for future work.

Performance studies on the treatment of VOCs in air streams by a pilot-scale regenerative catalytic oxidizer (RCO) and a full-scale regenerative thermal oxidizer (RTO) were conducted. The pilot-scale RCO was constructed with two 20-cm x 200-cm (inside diameter x packing height) regenerative beds packed with gravel (average particle size = 1.25 cm) used as the thermal regenerative solid material. Experimental results indicate that destruction efficiencies of 97 and 90%, respectively, were obtained for methyl ethyl ketone and toluene at a superficial gas velocity of 0.372 m/s (evaluated at 25¢J) and a maximum bed temperature of 400¢J. It was estimated that an electrical thermal energy of approximately 84 kWh was required for treating 1,000 m3 of the waste air stream by the RCO. The full-scale RTO was constructed with two regenerative beds of 100-cm square x 200-cm height packed with the gravel used in the RCO. A paint solvent containing methyl ethyl ketone, ethyl benzene, xylenes, and ethyl acetate was used for the target VOCs. Experimental results indicate that, at a superficial gas velocity of 0.372 m/s (evaluated at 25¢J), VOC destruction efficiencies of 84, 92, 95 and 98% were obtained for the beds at temperature ranges of 200-300, 300-500, 400-700, and 500-700¢J. These conditions corresponded to empty gas retention times of 1.07, 0.85, 0.41, and 0.39s, respectively, for the cited temperature ranges. Finally, it was estimated that electrical watts of approximately 0.10, 0.45, 1.78, 2.43 kWh were required for treating 1,000 m3 of the waste air stream, respectively, at bed temperature ranges of 200-300, 300-500, 400-700, and 500-700¢J.

The loss of regenerative capacity of bone, from fetal to adult to aged animals, has been attributed not only to a decline in the function of cells involved in bone formation but also to alterations in the bone microenvironment that occur through development and aging, including extracellular matrix (ECM) composition and growth/trophic factor content. In the development of novel treatments for bone repair, one potential therapeutic goal is the restoration of a more regenerative microenvironment, as found during embryonic development. One approach to creating such a microenvironment is through the use of stem cells. In addition to serving as a differentiated cell source, pluripotent stem cells, such as embryonic stem cells (ESCs), may possess the unique potential to modulate tissue environments via local production of ECM and growth factors. ESC-produced factors may be harnessed and delivered to promote functional tissue regeneration. Such an approach to generate a naturally derived, acelluar therapy has been employed successfully to deliver osteoinductive factors found within adult bone, in the form of demineralized bone matrix (DBM), but the development of treatments derived instead from developing, more regenerative tissues or cells remains attractive. Furthermore, the derivation of regenerative materials from an ESC source also presents the added benefit of eliminating donor to donor variability of adult, cadaveric tissue derived materials, such as DBM. Thus, the objective of this project was to examine the osteoinductive potential harbored within the embryonic microenvironment, in vitro and in vivo. The osteogenic differentiation of mouse ESCs as embryoid bodies (EBs) was evaluated in response to phosphate treatment, in vitro, including osteoinductive growth factor production. The osteoinductivity of EB-derived material (EBM) was then compared to that of adult tissue-derived DBM, in vivo. Phosphate treatment enhanced osteogenic differentiation of EBs. EBM derived from phosphate treated EBs retained bioactive, osteoinductive factors and induced new bone formation, demonstrating that the microenvironment within osteogenic EBs can be harnessed in an acellular material to yield in vivo osteoinductivity. This work not only provides new insights into the dynamic microenvironments of differentiating stem cells but also establishes an approach for the development of an ESC-derived, tissue specific therapy.

The concerted action of ion channels and pumps establishing a resting membrane potential has been most thoroughly studied in the context of excitable cells, most notably neurons, but emerging evidences indicate that they are also involved in controlling proliferation and differentiation of nonexcitable somatic stem cells. The importance of understanding stem cell contribution to tissue formation during embryonic development, adult homeostasis, and regeneration in disease has prompted many groups to study and manipulate the membrane potential of stem cells in a variety of systems. In this paper we aimed at summarizing the current knowledge on the role of ion channels and pumps in the context of mammalian corticogenesis with particular emphasis on their contribution to the switch of neural stem cells from proliferation to differentiation and generation of more committed progenitors and neurons, whose lineage during brain development has been recently elucidated.

Despite a comprehensive mapping of the Parkinson's disease (PD)-related mRNA and protein leucine-rich repeat kinase 2 (LRRK2) in the mammalian brain, its physiological function in healthy individuals remains enigmatic. Based on its structural features and kinase properties, LRRK2 may interact with other proteins involved in signalling pathways. Here, we show a widespread LRRK2 mRNA and/or protein expression in expanded or differentiated human mesencephalic neural progenitor cells (hmNPCs) and in post-mortem substantia nigra PD patients. Using small interfering RNA duplexes targeting LRRK2 in hmNPCs following their differentiation into glia and neurons, we observed a reduced number of dopaminergic neurons due to apoptosis in LRRK2 knockdown samples. LRRK2-deficient hmNPCs exhibited elevated cell cycle- and cell death-related markers. In conclusion, a reduction of LRRK2 expression in hmNPCs severely impaired dopaminergic differentiation and/or survival of dopaminergic neurons most likely via preserving or reactivating the cell cycle.