7 research outputs found
Stemple Pass (2012) et le projet Two Cabins : l’architecture de la solitude selon James Benning
No full textLe projet Two Cabins de James Benning gravite autour de la reproduction de deux cabanes dans l’espace de son jardin. La première est celle d’Henry David Thoreau, auteur transcendantaliste de Walden ou La vie dans les bois (1854). La seconde est celle de Theodore Kaczynski, aussi surnommé « Unabomber », écoterroriste états-unien et auteur d’un manifeste antitechnologique. Cet article se penche en particulier sur le film Stemple Pass (Benning, 2012), qui confronte les écrits de Kaczynski à la reproduction de son habitat.James Benning’s project Two Cabins revolves around the reconstruction of two cabins in his own yard (or garden). The first belongs to Henry David Thoreau, the transcendentalist author of Walden; or, Life in the Woods (1854). The second is that of Theodore Kaczynski, an ecoterrorist also known as “the Unabomber” who wrote an anti-technological manifesto. This article focuses on Stemple Pass, Benning’s 2012 film that juxtaposes Kaczynski’s writings and the reconstruction of his cabin
GEOWALL® as a Quay wall
No full textBank protections are currently constructed with stone, wood, concrete and steel. NETICS has introduced a sustainable and commercially very attractive alternative called the GEOWALL. The goal of this study is to find a viable field of application within the quay structures by considering the arising challenges of a larger scale wall. Additionally several potential design improvements are described to cope with the challenges. The GEOWALL could fail due to sliding, overturning, exceeding internal stresses, large deformations, vertical instability, overall instability and piping. The safety of the structure will be assessed with predefined general factors of safety and permissible internal stresses, these are the test values. The safety for sliding, overturning, large deformations, vertical stability and piping is calculated with an analytical method. The safety for overall stability, internal strength and large deformations is calculated with a finite element method. There are two main variables in the analyses: the retaining height and the type of soil. The retaining height varies between one and five metres. The soils are simplified to sand, clay and peat. From the results of the analytical analysis and the finite element analysis it can be concluded that sand-GEOWALLs on sand between one and three metres and clay-GEOWALLs on clay between one and three metres are the most viable scenarios for a larger scale GEOWALL with current design. For GEOWALL quay walls larger than three metres and peat-GEOWALLs on peat suitable design improvements are required to meet the stringent safety requirements. The design improvements should be able to limit the possibility of failure due to sliding, overturning and failure trough large deformations. There are three categories of potential improvements: material improvements, geometrical design improvements and structural design improvements. The embedded wall is expected to be the most promising geometrical design improvement. Adding a drainage system is expected to be the most promising structural design improvement at this moment. It is recommended to study the effects and efficiency of the proposed design improvements in future research. It is also recommended for NETICS to continue their research on the strength and resistance of different GEOWALL types and on the influence of every possible load. In case of a GEOWALL design for a specific location it is recommended to determine the safety factors for that specific location and to check the analytical results with more advanced modelling programmes. Lastly it is recommended to consider not only the technical aspects, but also the practical and commercial aspects if one is investigating the design improvements.Hydraulic EngineeringCivil Engineering and Geoscience
Towards real-time identification of brain tumors by integrating diffuse reflectance spectroscopy in a neurosurgical instrument
No full textBrain tumors account for approximately just 2% of all cancers worldwide, but have a noticeable impact on cancer morbidity and mortality. Removal of brain tumors poses a big challenge for neurosurgeons, pediatricians and neuro-oncologists. An important aspect of this challenge is to adequately differentiate between tumor tissue and healthy brain tissue. Tumors that are located within the eloquent cortex (functional brain cortex and major white matter fiber tracts) pose a particular surgical challenge due to the high risk of postoperative neurological deficits. Together with the In-Body Systems department of Philips Research and the Karolinska Institute in Sweden, the Delft University of Technology is participating in a new research focusing on adding diffuse reflectance spectroscopy in a neurosurgical instrument that can aid in better identifying the brain tumor margin. Previous research has used diffuse reflectance spectroscopy or a combination of diffuse reflectance and tissue fluorescence from endogenous (e.g., NADPH), exogenous (e.g., fluorescein), or exogenously induced fluorophores (e.g., PpIX) to identify spectral differences between healthy brain tissue and brain tumor tissue over a range of 400-900 nm. This master thesis presents the spectral differences between healthy and tumorous tissue over a range of 400-1600 nm, while using a spectroscopic tool, to better determine the demarcation of brain tumor margins with increased accuracy. The differences in optical characteristics in healthy brain tissue (i.e. white and gray matter) and human brain tumor tissue were identified. Furthermore, it was investigated whether the optical characteristics can provide a means to quantify the distinction between healthy and brain tumor tissue. Clear differences were found in the spectra between the different tissues. In the visible region higher values for the absorption coefficient were identified as indicators for tumor tissues. In the near infrared region clear distinctions in the diffuse reflectance spectra were observed between gray matter, tumor tissue and white matter, with gray matter presenting the highest value. The reduced scattering coefficient showed especially a clear distinction for white matter, presenting the highest values, compared to gray matter and tumor tissue. This was in line with the measurements of the scattering parameters and the fat fraction, with white matter presenting the highest value which can be explained due to its myelinated axons. For the other investigated parameters, an increased level of blood concentration and lower levels of StO2 were indicated as biomarkers for the tumor tissues. However, both physiological parameters are likely to change from in vivo to ex vivo settings which require that they should be investigated in in vivo experiments first before statements about their reliability can be made. The study was followed with a clinical workflow analysis, to identify the most promising neurosurgical instrument used during craniotomy in which diffuse reflectance spectroscopy can be integrated. Based on observations at brain tumor surgeries, open interviews with neurosurgeons and an investigation on several instruments, the suction cannula was found to be the most promising neurosurgical instrument to combine with diffuse reflectance spectroscopy. Finally, a prototype was designed and tested. In addition, it was investigated whether different amounts of suction power had an influence on the accuracy of the measured spectra while performing measurements with the prototype on healthy pig brain tissue. Overall, it can be concluded that spectral differences between healthy and tumorous tissue can be observed with the prototype and future research should increase the amount of data to verify these results. Furthermore, in vivo measurements should indicate whether these findings are consistent when the physiology of the tissues changes
Project Veracruz: An assessment for the eroding beach south of Veracruz
No full textDue to frequently occurring storms, like hurricanes and cold fronts, the coasts around the Mexican port city Veracruz suffer from erosion. This is most severe at the beaches of Boca del Rio just south of the city of Veracruz. Here, small beaches can be found between large groynes. These groynes block the southward littoral drift significantly but proved not to provide protection against episodic storm erosion. The cause of the erosional problem is in cross-shore direction, therefore solutions should be considered which act in this direction as well. Eventually a nourishment, a dune, an offshore submerged breakwater and a beach toe were designed as possible solutions. Firstly the impact on the current situation is simulated which is referred to as the do-nothing situation. Afterwards, runs were done with an XBeach model to check the storm impact on the beach profile for several combinations of the solutions mentioned above. To evaluate the simulations above six criteria were taken into account with different importance. The extent to which the erosion is counteracted and the costs are the most important criteria, besides values for the sustainability, durability, recreational value and hindrance contribute as well to the total score of a considered solution. Finally two combinations showed interesting results. On the one hand a nourishment and on the other hand an uninterrupted submerged breakwater in combination with a nourishment. Both can additionally be combined with a dune resulting in a slightly higher value due to better performance and higher recreational value. \u95 A nourishment is initially a cheap solution, but has to be maintained every few years by additional nourishments, resulting in increasing costs and hindrance for beach recreation. A large benefit of only performing beach nourishment is that abundance of sand will be available due to extension works at the port of Veracruz. \u95 The combination of a breakwater and a nourishment requires a high initial investment. The result however is a very durable solution which will protect the coastal system for many years without maintenance. Besides the costs a disadvantage is that large amounts of rock have to be imported to construct the breakwater, which does not contribute to a sustainable solution. Eventually it depends on the national and local governments which of the solutions above will be performed. They can choose between a very durable solution with high initial investments or an initially cheaper solution which is sustainable but demands frequent maintenance.Hydraulic EngineeringCivil Engineering and Geoscience
Women and Landed Property in Urban India: Negotiating Closed Doors and Windows of Opportunity
No full textThis paper examines land tenure in informal urban settlements in India from a gender perspective through field research conducted in Ahmedabad in collaboration with the Self-Employed Women's Association (SEWA). The author describes the formal and informalwomen, landed property, cities, India, South Asia
A comparative study of Tam3 and Ac transposition in transgenic tobacco and petunia plants
No full textTransposition of the Anthirrinum majus Tam3 element and the Zea mays Ac element has been monitored in petunia and tobacco plants. Plant vectors were constructed with the transposable elements cloned into the leader sequence of a marker gene. Agrobacterium tumefaciens-mediated leaf disc transformation was used to introduce the transposable element constructs into plant cells. In transgenic plants, excision of the transposable element restores gene expression and results in a clearly distinguishable phenotype. Based on restored expression of the hygromycin phosphotransferase II (HPTII) gene, we established that Tam3 excises in 30% of the transformed petunia plants and in 60% of the transformed tobacco plants. Ac excises from the HPTII gene with comparable frequencies (30%) in both plant species. When the β-glucuronidase (GUS) gene was used to detect transposition of Tam3, a significantly lower excision frequency (13%) was found in both plant species. It could be shown that deletion of parts of the transposable elements Tam3 and Ac, removing either one of the terminal inverted repeats (TIR) or part of the presumptive transposase coding region, abolished the excision from the marker genes. This demonstrates that excision of the transposable element Tam3 in heterologous plant species, as documented for the autonomous element Ac, also depends on both properties. Southern blot hybridization shows the expected excision pattern and the reintegration of Tam3 and Ac elements into the genome of tobacco plants.
