Exploring the Use of Re-Forming Concrete

This thesis takes a closer look at concrete construction in the modern area and, more specifically, the use of formwork to shape the built environment. Traditional rigid concrete formwork has been optimized for buildability while serving structural needs. This mentality means simple prismatic elements that are entirely overbuilt for the task, stacked on top or next to one another. The idea that these elements are the peak of efficiency in concrete production has informed virtually all modern concrete construction. Any shapes that vary from the simple prismatic volumes are seen as challenging to build and expensive. For the most part, this is true if traditional methods of constructing formwork are used to create those shapes, but what if that did not have to be the case? Over the last 100 years, several alternative methods of building formwork have been suggested, but almost all of them have stayed almost entirely in the academic realm. The major categories of these technologies include flexible formwork, such as fabrics; Folding formwork, using materials such as fiberglass; 3D printing formwork, using plastics; and even Knitted formwork. The major challenge that most of these technologies face is that they only propose formwork to replace select elements needed to construct a building, and this leads to a strange mix of architectural languages that is not desirable. Even if they include multiple elements, they often use vastly different systems and materials to create the framework, making them not viable at larger building scales. This thesis looks at the use of structurally optimized formwork systems in architectural buildings. The aim is to combine math, material science, and architectural design in an interdisciplinary effort to better the built environment. In part motivated by the artwork of Mark West and informed by structural engineering concepts, this thesis aims to advance the fundamental understanding of concrete formwork systems in an effort to marry architectural form and structural design by creating a new design language for concrete construction. Stemming from the architectural, structural, and construction considerations, this thesis will investigate the use of different formwork systems in concrete structures to achieve: 1. More economical construction practices while improving sustainability and resilience of concrete structures. 2. Nontraditional and varying architectural forms using parametric design solutions. 3. The adoption of new applications for advanced concrete materials such as engineered cementitious composites. The objective is to define an architectural language for concrete structures that will introduce a new design for formwork systems as well as explore solutions to minimize the use of reinforcement without sacrificing structural integrity. The goals are to evaluate the new design strategies and computational tools so that they can seamlessly integrate architectural forms with structural needs. Based on previous research, this approach could lead to an approximately 40% reduction in concrete usage, dramatically affecting the sustainability of such a building. In order to achieve these results, individual structural elements and their formwork systems will be analyzed and evaluated for their strengths and weaknesses, followed by an investigation of how these different systems can be combined into one unified language using one type of formwork. Nevertheless, why is any of this relevant for the future? Well, despite the inefficiencies associated to traditional formwork, concrete remains one of the most widely used manufactured materials globally, with the global production of cement reaching 4.1x10^9 t in 2017. According to data, concrete use has become so prevalent that it is now the second most consumed commodity after water. Although concrete has a relatively low embodied energy, its rate of production and uses account for almost 9% of total global anthropogenic greenhouse gas emissions. Against a backdrop of the carbon dioxide emissions reduction targets a recognition of the significant impact construction has on the natural environment, and an increasing client focus on sustainability, design philosophies centered around the need to put material where it is required are becoming increasingly desirable. Therefore, creating a formwork system that saves on formwork costs and reduces the amount of concrete needed in total would be extremely valuable

History and Technique in Reinforce Concrete Formworks: A study of Pier Luigi Nervi Approach

The last hundred years in architecture and civil engineering have been widely dominated by the use of concrete, which became the second most consumed commodity after water. The traditional use of rigid, flat formwork panels has defined reinforced concrete members as a uniform cross-section, prismatic structural elements in both design codes and construction methods. These resultant shapes have become practically an inevitable conclusion for concrete constructions. This presentation focuses on alternative formwork construction looking at the work of engineer, architect and builder, Pier Luigi Nervi (1891–1979). Nervi was an adjunct professor at the University of Rome and a prolific writer, which used formwork to define the ever-evolving relationship between building forms, techniques and materials. Seeing technique as preceding form, he examined structural elements that resisted the passage of time and outlasted building typologies and styles. Combining Nervi’s published and unpublished work, this presentation explores Nervi’s style through the lens of architectural formwork, placing the engineer’s use of reinforced concrete in the particular historicity of this material and in the longer continuum of construction history

Environmental factors on 2D material properties: influence of underlying Au(111) vs amorphous gold on the local density of states in graphene

Two dimensional (2D) materials have taken material science and solid state physics by storm. Learning about these fascinating new materials relies on researcher’s ability to reliably create them and to be in control of the many parameters that can impact their properties. In this work I discuss the methods of 2D material exfoliation, transfer, and device assembly, and how these methods allow researchers to control environmental factors, such as substrate, contamination, and strain, that can impact 2D material properties. I also discuss challenges and lessons learned in employing these 2D material processing methods. Additionally, I present the results of an annealing experiment on a graphene on gold sample. Annealing resulted in an increase in the crystallinity of the gold. Different local density of states (LDOS), as measured by dI/dV spectra from scanning tunneling spectroscopy, were found in areas on the graphene with single crystalline, stepped, and amorphous underlying gold structure. The influence of underlying gold structure on the LDOS of graphene is explored. The observations from this experiment support the idea that 2D materials are greatly influenced by their substrate and improve our understanding of the complex relationship between graphene and gold

Sustainable Building Materials of the Future: Architectural Forms and Structural Design

This research investigates the use of non-rigid formwork and the techniques aiming to create more efficient concrete forms. During casting, concrete takes the shape of its formwork; traditionally, these formworks are made of rigid materials like steel or wood. The results are prismatic members, which are not optimized for material usage but only for simplicity in construction. Most of the research in the area focuses on improving the constituent materials, while the formworks have remained unchanged throughout the years. By using the approach described in this study, optimized shapes are achieved. These geometries can save up to 30% of the material while maintaining the same strength. In this study, we investigated the structural capacity of reinforced concrete members built with this technique along with the necessary solutions to perform better casts. Formworks were improved with each cast until a consistent method of creating the desired beam shape was achieved. Using both software are standard laboratory tests, the data were collected and analyzed. The results show that flexible forms can create more environmentally friendly concrete structures. Our research also opened up new questions. How can the processes be more streamlined, and are there real-world applications? This research investigates the use of non-rigid formwork and the techniques aiming to create more efficient concrete forms. During casting, concrete takes the shape of its formwork; traditionally, these formworks are made of rigid materials like steel or wood. The results are prismatic members, which are not optimized for material usage but only for simplicity in construction. Most of the research in the area focuses on improving the constituent materials, while the formworks have remained unchanged throughout the years. By using the approach described in this study, optimized shapes are achieved. These geometries can save up to 30% of the material while maintaining the same strength. In this study, we investigated the structural capacity of reinforced concrete members built with this technique along with the necessarily solutions to perform better casts. Formworks were improved with each cast until a consistent method of creating the desired beam shape was achieved. Using both software are standard laboratory tests, the data were collected and analyzed. The results show that flexible forms can create more environmentally friendly concrete structures. Our research also opened up new questions. How can the processes be more streamlined, and are there real-world applications

MUG-Mel2, a novel highly pigmented and well characterized NRAS mutated human melanoma cell line

NRAS mutation in melanoma has been associated with aggressive tumor biology and poor prognosis. Although targeted therapy has been tested for NRAS mutated melanoma, response rates still appear much weaker, than in BRAF mutated melanoma. While plenty of cell lines exist, however, only few melanogenic cell lines retain their in vivo characteristics. In this work we present an intensively pigmented and well-characterized cell line derived from a highly aggressive NRAS mutated cutaneous melanoma, named MUG-Mel2. We present the clinical course, unique morphology, angiogenic properties, growth characteristics using in vivo experiments and 3D cell culture, and results of the exome gene sequencing of an intensively pigmented melanogenic cell line MUG-Mel2, derived from a cutaneous metastasis of an aggressive NRAS p. Q61R mutated melanoma. Amongst several genetic alterations, mutations in GRIN2A, CREBP, PIK3C2G, ATM, and ATR were present. These mutations, known to reinforce DNA repair problems in melanoma, might serve as potential treatment targets. The aggressive and fast growing behavior in animal models and the obtained phenotype in 3D culture reveal a perfect model for research in the field of NRAS mutated melanoma.Peer reviewe

Gender Differences in Clinical Presentation and Outcomes of Epidemic Kaposi Sarcoma in Uganda

The incidence of Kaposi sarcoma (KS) has increased dramatically among women in sub-Saharan Africa since the onset of the HIV pandemic, but data on KS disease in women are limited. To identify gender-related differences in KS presentation and outcomes, we evaluated the clinical manifestations and response in men and women with AIDS-associated KS in Uganda.HIV-infected adults with KS attending the Infectious Diseases Institute (IDI) and Uganda Cancer Institute (UCI) in Kampala, Uganda between 2004 and 2006 were included in a retrospective cohort. Evaluation of KS presentation was based on the clinical features described at the initial KS visit. Response was evaluated as the time to "improvement", as defined by any decrease in lesion size, lesion number, or edema. The cohort consisted of 197 adults with HIV and KS: 55% (108/197) were women. At presentation, the median CD4 T-cell count was significantly lower in women (58 cells/mm(3); IQR 11-156 cells/mm(3)) than men (124 cells/mm(3); IQR 22-254 cells/mm(3)) (p = 0.02). Women were more likely than men to present with lesions of the face (OR 2.8, 95% CI, 1.4, 5.7; p = 0.005) and hard palate (OR 2.0, 95% CI, 1.1, 3.7; p = 0.02), and were less likely than men to have lower extremity lesions (OR 0.54, 95% CI, 0.3, 0.99; p = 0.05). Women were less likely than men to demonstrate clinical improvement (HR = 0.52, CI 0.31, 0.88; p = 0.01) in multivariate analysis.The clinical presentation and response of KS differs between men and women in Uganda. These data suggest that gender affects the pathophysiology of KS, which may have implications for the prevention, diagnosis, and treatment of KS in both men and women. Prospective studies are needed to identify predictors of response and evaluate efficacy of treatment in women with KS, particularly in Africa where the disease burden is greatest

Dose Response for Starting and Stopping HIV Preexposure Prophylaxis for Men Who Have Sex With Men

Background. This study estimated the number of daily tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) doses required to achieve and maintain (after discontinuation) intracellular drug concentrations that protect against human immunodeficiency virus (HIV) infection for men who have sex with men (MSM). Methods. Tenofovir diphosphate (TFV-DP) concentrations in peripheral blood mononuclear cells (PBMCs) and rectal mononuclear cells from an intensive pharmacokinetic study ("Cell-PrEP" [ preexposure prophylaxis]) of 30 days of daily TDF/FTC followed by 30 days off drug were evaluated. A regression formula for HIV risk reduction derived from PBMCs collected in the preexposure prophylaxis initiative study was used to calculate inferred risk reduction. The time required to reach steady state for TFV-DP in rectal mononuclear cells was also determined. Results. Twenty-one HIV-uninfected adults participated in Cell-PrEP. The inferred HIV risk reduction, based on PBMC TFV-DP concentration, reached 99% (95% confidence interval [CI], 69%-100%) after 5 daily doses, and remained >90% for 7 days after stopping drug from steady-state conditions. The proportion of participants reaching the 90% effective concentration (EC 90 ) was 77% after 5 doses and 89% after 7 doses. The percentage of steady state for natural log [TFV-DP] in rectal mononuclear cells was 88% (95% CI, 66%-94%) after 5 doses and 94% (95% CI, 78%-98%) after 7 doses. Conclusions. High PrEP activity for MSM was achieved by approximately 1 week of daily dosing. Although effective intracellular drug concentrations persist for several days after stopping PrEP, a reasonable recommendation is to continue PrEP dosing for 4 weeks after the last potential HIV exposure, similar to recommendations for postexposure prophylaxis