1,216 research outputs found
Port expansion project: Port of Phillipsburg St. Maarten Netherlands Antilles
No full textThe Sint Maarten Ports Authority (SMPA) , wishes to expand the present port of Phillipsburg, due to the increase of cargo throughput and forecast for the cruise tourism. The SMPA has appointed Grabowsky&Poort International BV as the main consultants for the port development. To give this report a more complete character, a summary of the Port Lay-out Study, the Wave Climate Study [ref.: 3J and the wave Penetration Study [ref.: 2J are included. These three studies were performed during my work emplacement at GrabowskY&Poort International BV.Hydraulic EngineeringCivil Engineering and Geoscience
Ontwikkeling en evaluatie van geoptimaliseerde bacteriofaagendolysines ter inactivatie van gramnegatieve bacteriën.
No full textBacteriophages, viruses infecting bacteria, disrupt the bacterial cell wall at the end of their replication cycle to release newly produced virions. The major constituent of the bacterial cell wall is the peptidoglycan. To degrade this rigid layer, bacteriophages encode peptidoglycan hydrolases, called endolysins, that hydrolyze specific bonds in the peptidoglycan. This dissertation specifically focuses on endolysins, isolated from phages infecting Gram-negative bacterial species, including Pseudomonas aeruginosa, Salmonella Typhimurium, Escherichia coli, Klebsiella pneumoniae and Citrobacter rodentii. Most of these bacteria are opportunistic pathogens that are of increasing concern in hospitals due to their high intrinsic and acquired antibiotic resistance. In a first part of this study, we extend the pool of available endolysins from Gram-negative origin and analyze their potential and applicability as alternative antibacterial agents for antibiotics to combat these Gram-negative pathogens. The Gram-negative outer membrane prevents exogenously applied endolysins from reaching the peptidoglycan layer and protects bacteria against their lytic activity. We therefore evaluate in the second part of this dissertation an approach that allows the endolysin to efficiently destabilize the outer membrane and subsequently reach the peptidoglycan. This approach consists of the fusion of a set of outer membrane-permeabilizing antimicrobial peptides to the endolysin to allow for an autonomous interaction with the outer membrane. To sketch the background, this dissertation starts with an overview of the literature concerning bacteriophage endolysins (history and structural diversity), antimicrobial peptides (types and mode of action) and outer membrane diversity present among Gram-negative bacteria.From an in silico analysis of fully sequenced phage genomes, a selection of fifteen interesting candidate endolysins is made (Chapter 4). Six single-domain (Chapter 5) and three modular (Chapter 6) endolysins with the highest maximal muralytic activity under physiological conditions, are selected for extensive characterization on biochemical (pH-dependency, enzymatic activity, activity upon heating) and antibacterial level. In this way, we aim to prove their lytic role and to reveal enzyme-specific characteristics interesting from an application perspective. In silico, the single-domain endolysins consist of a catalytic domain, whereas the modular ones feature an N-terminal peptidoglycan binding domain and a C-terminal catalytic domain, hitherto a unique property present in a few endolysins from Gram-negative origin. In addition, the predicted peptidoglycan binding domains are experimentally verified.The modular endolysins in this study are shown to be enzymatically more active than the single-domain endolysins, an observation that was translated into their in vitro antibacterial activity. Of all tested endolysins, the modular endolysin from Pseudomonas fluorescens phage OBP, OBPgp279, shows the highest muralytic and antibacterial activity, followed by PVP-SE1gp146, the endolysin from Salmonella Enteritidis phage PVP-SE1. The peptidoglycan binding domain present in modular endolysins accounts for their strong lytic action since the contribution of this domain (38 to 56 %) to the total enzymatic activity is considerable. In addition, the enzymatic activity is consistent for the different Gram-negative bacterial species due to their conserved peptidoglycan (A1gamma chemotype). This characterization also revealed various interesting biochemical properties. OBPgp279 shows intrinsic antibacterial activity on P. aeruginosa PAO1 (± 1 log unit), probably by destabilizing the Pseudomonas outer membrane. PVP-SE1gp146 remains active up to temperatures of 90°C with 60 % residual enzymatic activity after 40 minutes. This last property makes the enzyme a potential candidate as antibacterial component in hurdle technology for food preservation. At the start of the second part, OBPgp279 and PVP-SE1gp146, the two most promising endolysins, are selected to evaluate the proposed fusion approach for passage of the outer membrane (Chapter 7). The N-terminal fusion of a polycationic PK peptide (KRKKRKKRK) composed of lysine and arginine residues, turns out to be the most effective fusion to improve the antibacterial activity of both endolysins. The highest activity is reached for P. aeruginosa with maximal 2.61 log units. Addition of minor EDTA concentrations enhances activity and extends the activity range with E. coli (maximal 1.70 log units) and S. Typhimurium (maximal 0.91 log units). This fused PK peptide is believed to compete with the Achilles heel of the outer membrane: the stabilizing divalent cations. A double N-terminal fusion of this promising PK peptide with other antimicrobial peptides only increases the antibacterial activity of OBPgp279 against E. coli to maximal 2.22 log units (for PP-PK double fusion), but is detrimental for the activity against other Gram-negative species. Analysis for the impact of the N-terminal PK fusion on endolysin characteristics reveals a protein-dependent inhibition of the enzymatic activity (with 52 to 94 %), a reduced heat resistance and a switch in pH-dependency to slightly more alkaline values (Chapter 8). Due to a more hydrophobic outer membrane, the antibacterial efficacy of the PK fusion is limited for Enterobacteriaceae. Additionally, the PK fusion also confers biofilm-degrading activity to PVP-SE1gp146. Extension of the linker length between the PK peptide and endolysin partly reconstitutes the reduced muralytic activity due to the PK peptide fusion, leading to an improved antibacterial activity against Pseudomonads and Enterobacteriaceae. Switching the PK peptide to the C-terminal end does not improve activity. These data nicely illustrate that endolysins can be turned into effective anti-Gram-negative compounds by an N-terminalfusion approach and subsequent optimization of the linker length.In the last part, we evaluate the PK-fused endolysin approach on an in vitro human keratinocyte monolayer and an in vivo Caenorhabditis elegans model. PK-PVP-SE1gp146 is able to protect the keratinocyte monolayer from a P. aeruginosa PA14 infection (Chapter 9). In addition, PK-PVP-SE1gp146 improves the survival of PA14-infected C. elegans with 60 % after five days of treatment (Chapter 10). These results prove the in vitro and in vivo applicability of the PK-fused endolysin approach against P. aeruginosa, offering promising perspectives towards prophylactic and therapeutic applications in human health and veterinary and towards microbial decontamination purposes in the food industry.status: Publishe
Hoe God aanwezig is in het werk van Maarten ’t Hart
No full textMaarten ’t Hart is widely regarded as the prototypical Dutch author who has left his Orthodox Reformed background behind. Yet religion is present throughout his work. In her dissertation Religion im Werk von Maarten ’t Hart (2022), German theologian Christina Bickel describes the playful manners in which ’t Hart deals with religion as an inspiring way to open the mind of modern man to transcedental reflections. Her interdisciplinary approach combining literary analysis, theological hermeneutics and homiletics, offers a surprising example of the reception of a Dutch author within a foreign cultural context.Maarten ’t Hart is widely regarded as the prototypical Dutch author who has left his Orthodox Reformed background behind. Yet religion is present throughout his work. In her dissertation Religion im Werk von Maarten ’t Hart (2022), German theologian Christina Bickel describes the playful manners in which ’t Hart deals with religion as an inspiring way to open the mind of modern man to transcedental reflections. Her interdisciplinary approach combining literary analysis, theological hermeneutics and homiletics, offers a surprising example of the reception of a Dutch author within a foreign cultural context.Maarten ’t Hart is widely regarded as the prototypical Dutch author who has left his Orthodox Reformed background behind. Yet religion is present throughout his work. In her dissertation Religion im Werk von Maarten ’t Hart (2022), German theologian Christina Bickel describes the playful manners in which ’t Hart deals with religion as an inspiring way to open the mind of modern man to transcedental reflections. Her interdisciplinary approach combining literary analysis, theological hermeneutics and homiletics, offers a surprising example of the reception of a Dutch author within a foreign cultural context
CAY HILL: The possibilities of creating a synergy between an informal settlement, local craftmanship and cultural economic opportunities on Sint Maarten
No full textOn September 6th of 2017 Sint Maarten got struck by Hurricane Irma, which caused severe damage to the houses, especially to the informal settlements. Sint Maarten is a Caribbean island with a rooted past from its history that has caused severe economic difficulties. Along with, a high amount of migration that has been common among he islands, Sint Maarten has a tourism-led economy. In Turn, the hurricane also affected the tourism-led economy as many visits to the island declined. Lots of building materials on the island are getting imported. The island is lacking of local building resources and knowlegde. This project aims to propose an alternative housing solution and local economic business model for the people living in the informal settlement Cay Hill. This study is investigating the possibilities of creating a synergy between an informal settlement, local craftmanship and cultural economic opportunities on Sint Maarten.Architecture, Urbanism and Building Science
Humanitarian Innovation at the Netherlands Red Cross: A case study on disaster preparedness on Sint Maarten
No full textThis report shows the process and result of a graduation project at the Netherlands Red Cross (NLRC). In their search to improve the humanitarian system, innovation is necessary. However, the Netherlands Red Cross faces challenges associated with time, resources, culture and methodologies to execute a research regarding the integration of innovation into the organisation. Based on this problem the following research question was formulated:“How can humanitarian innovation at the Netherlands Red Cross be improved?”To answer this research question, two ethnographic studies were conducted in the context of the headquarters of the Netherlands Red Cross and Red Cross operation on Sint Maarten. Ethnographic research is a qualitative research method in which you observe, interact and empathise with the topic that is being researched. It is mainly used to gain a deep understanding of the context when dealing with highly complex problems.Ethnographic Study 1The first ethnographic study took place at the headquarters of the Netherlands Red Cross, involving methods such as observations and interviews. The research resulted in a general understanding of the way of working at the NLRC. Furthermore, multiple bottlenecks of innovation were identified: Donor structure, organisational silos and project proposals.Ethnographic Study 2The second ethnographic study was conducted on Sint Maarten. The island, located in the hurricane prone Caribbean, was hit by hurricane Irma in September 2017. The Red Cross responded and provided relief aid to the inhabitants of Sint Maarten. The field visit, which had a focus on disaster preparedness, allowed research into the programming of the Red Cross on Sint Maarten. The following insights were found: Design principlesThe Red Cross should follow the the following five design principles; (1) embrace a holistic approach; (2) pivot the existing situation; (3) ensure knowledge is transferred; (4) use a context specific approach and; (5) use a phase specific approach.Organisational insightsThrough collaboration, the missing identified qualities: creativity, ideation, speed, hands-on approach and decisiveness, can be implemented into (future) projects.ConceptThe concept, ‘Community Based Data Collection’, that was developed for this thesis consists of three different phases: preparation, quick response and long-term benefits. Each neighbourhood will have a local ‘data collector’ with knowledge of the community, which will gather relevant data for the three different phases. Preparation• Identify the most vulnerable people in the communities by mapping the neighbourhoods;• Use data to estimate the quantity of relief good necessary per community, and;• Identify and map valuable capacities on the island for a ‘sharing economy (relief operation)’.Response• Use data from the preparation phase to deliver appropriate and focussed aid;• Use a communication system (e.g. pop-up wifi) to provide communication possibilities for both beneficiaries and the Red Cross, and;• Use real time data to optimize relief aid.Long-term benefits• Identify and map structural problems on Sint Maarten;• Provide information to specialized organisations in order to solve these problems, and;• Create a financial independent project by having a ‘data based business model’.Strategic Product Desig
A Resilient Community: Housing for Sint Maarten
No full textSint Maarten is a Caribbean island that is located in one of the six tropical zones were hurricanes may develop each year. The island deals with a limited resilient housing stock due to the lack of building regulations and affordable materials and contractors. This results in a community that needs to rebuild the housing stock every time a hurricane hits. In addition, most people lose their jobs after a hurricane because the numbers of tourists drop. This project attacks this problem by making resilient housing with plastic roofs. Plastic waste can be harvested locally and be used as a building element. This way a newindustry is developed and creates more local job opportunities. By designing understandable units, that are close to the traditional way ofbuilding and are prefabricated and supervised, the resiliency is guaranteed. This project let to promising results in reusing plastic as a building material for resilient housing. Additional research could be performed on the more technical effect of wind forces on recycled plastic roofs. Architecture, Urbanism and Building Science
The New Capital of Spanish Language Literature: The Best Seller
No full textThis translation was originally published as:
“The New Capital of Spanish Language Literature: The Best Seller.” New Spain New Literatures, by Maarten Steenmeijer. Eds. Luis Martín Estudillo and Nicholas Spadaccini. Vanderbilt UP (81-98). Invited Translator. Book chapter. (2010)
Reintroducing tropicality to St. Maarten: A residential typology rooted in the soil of the past
No full textSt. Maarten has been subject to outside influences since its existence. From the indians that traveled through the caribbean and made their stops on the island 3500 years ago, until the time that the economy started to influence the way that life is lived. From the 1950s onward, the tourism sector started to grow which provides income for the largest part of the people on St. Maarten. This economical prosperity increased the total population from a little over 2000 inhabitants in 1955 to around 42.000 people today, excluding the illegal immigrants (which is said to be around 30.000 more people). This accounts only for the dutch side of the island. St. Maarten has had to expand very quickly from the 1950’s and these expansions resulted in relatively monotonous urban environments where public space is scarce and social interactions do not occur alot. The buildings are built in a farely standard way which are mostly bungalows constructed out of concrete. The buildings and neighborhoods do not respond to the tropical savannah climate that they are in and when walking through a typical middle class neighborhood you would not expect these buildings in a tropical climate.This way of building was not always a normality. Before 1950 the buildings on the island looked like they did in the picture in the top right border. Buildings were constructed using a wooden frame and wood finishes placed on a foundation of local natural stones. This way of building fits the natural climate better because these buildings are light and have more openings in the facades to let i natural ventilation. Yet, there is one aspect of the climate that made these buildings disappear which is the hurricanes that occur once every couple of years. Concrete ofcourse is a stronger material and quickly became more popular when it became more affordable than wood.This project is a exploration to design a residential typology which not only responds to all aspects of St. Maarten’s climate but also its context and culture.Architecture, Urbanism and Building Sciences | Intectur
Senator James Eastland discussion
No full textMaarten Zwiers, a 2007 Ole Miss graduate from the Netherlands, became so interested in his study of the South that he became this year the author of the first full-length biography of the man who dominated politics in the state for a generation. Zwiers returns to campus to describe how Eastland was a power to be reckoned with in Washington, too
Emergency Evacuation Behavior in Small Island Developing States: Hurricane Irma in Sint Maarten
No full textDisasters triggered by natural hazards are becoming more frequent and more intense, causing damage to infrastructure and causing loss of life. One way to reduce disaster risk is by evacuating the hazardous area. However, despite the amount of literature that exists on evacuation behavior, there is still a lack of agreement on which variables can be used as predictors for individuals (or households) to actually evacuate. This lack of agreement can be related to the many variables that can affect the evacuation decision, from demographics, geographic, the hazard itself, and also local or cultural differences that may influence evacuation. Hence, it is essential to analyze and understand these variables based on the specifics of a case study. This study aims to find the most significant variables to be used as predictors of evacuation on the island of Sint Maarten, using data collected after the disaster caused by Hurricane Irma in September 2017. The results suggest that the variables gender, homeownership, percentage of property damage, quality of information, number of storeys of the house, and the vulnerability index are the most significant variables influencing evacuation decisions on the island. We believe the results of this paper offer a clear view to risk managers on the island as to which variables are most important in order to increase evacuation rates on Sint Maarten and to plan more efficiently for future evacuations. In addition, the variables found in this study have the potential to be the base information to set up, validate, and calibrate evacuation models.</p
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