36 research outputs found
LECOFISH: an ecosystem approach in sustainable fisheries management through local ecological knowledge
LECOFISH collected fisheries information and spatial data through the use of âLocal Ecological Knowledgeâ (LEK). The objective was to improve ecosystem knowledge and sustainable fisheries management in the Belgian Part of the North Sea (BPNS) by making use of oral information gathered from professional and recreational fishermen during a period of 50 years (1960-2010). This information allows analyzing spatial and temporal distribution of fishery activities in the BPNS based on catches. LECOFISH is the first Belgian study to translate fishermenâs LEK into spatial maps for the BPNS
A glycosylphosphatidylinositol-anchored carbonic anhydrase-related protein of Toxoplasma gondii is important for rhoptry biogenesis and virulence
Carbonic anhydrase-related proteins (CARPs) have previously been described as catalytically inactive proteins closely related to α-carbonic anhydrases (α-CAs). These CARPs are found in animals (both vertebrates and invertebrates) and viruses as either independent proteins or domains of other proteins. We report here the identification of a new CARP (TgCA_RP) in the unicellular organism Toxoplasma gondii that is related to the recently described η-class CA found in Plasmodium falciparum. TgCA_RP is posttranslationally modified at its C terminus with a glycosylphosphatidylinositol anchor that is important for its localization in intracellular tachyzoites. The protein localizes throughout the rhoptry bulbs of mature tachyzoites and to the outer membrane of nascent rhoptries in dividing tachyzoites, as demonstrated by immunofluorescence and immunoelectron microscopy using specific antibodies. T. gondii mutant tachyzoites lacking TgCA_RP display a growth and invasion phenotype in vitro and have atypical rhoptry morphology. The mutants also exhibit reduced virulence in a mouse model. Our results show that TgCA_RP plays an important role in the biogenesis of rhoptries
Effects of a hand luggage guiding system on airplane boarding time and passenger experience
This research investigates whether a hand luggage guiding system in overhead bins decreases boarding time and improves boarding experience during aircraft boarding process. A guiding system was developed which allocates and displays the passengers luggage space in the overhead bin. The allocated space is guided by a light strip in front of the display that blinks when a passenger comes close to their allocated luggage space. This system was tested in a Boeing 737 test fuselage. Compared to regular boarding, a boarding time reduction of 16 to 23 seconds was estimated using the hand luggage guiding system in groups of 18 passengers compared with the traditional way of boarding. This corresponds to 3 to 4 minutes of boarding time reduction on a Boeing 737-800 aircraft with 189 passengers. In addition, the boarding experience of the new system was significantly higher than regular boarding. Although this system has potential, it is recommended to test it while boarding in an actual flight with passengers
Improving airplane boarding time: a review, a field study and an experiment with a new way of hand luggage stowing
The airplane (de)boarding process is not organized optimally. The goal of this paper is to search for improvement possibilities. In this paper literature is reviewed, boarding characteristics are studied in a field study and a pilot study with a new way of hand luggage stowing is performed. Computer simulations indicate that there are more efficient boarding methods than those currently in use, like the reverse pyramid method which starts window seat columns in the back and ends with aisle seat columns in the front. The literature also shows that hand luggage stowing in the overhead lockers can block other passengers increasing the boarding time. Also, the field observations and the pilot test indicate that hand luggage stowing could block the aisle and is one of the main elements in boarding that influences passenger experience and boarding time. Training and preparing the boarding process could potentially reduce the boarding time by 3-4 minutes, but further research is needed to prove this
Population pharmacokinetics of factor IX in hemophilia B patients undergoing surgery
Essentials Factor IX (FIX) dosing using body weight frequently results in under and overdosing during surgery. We aimed to establish a population pharmacokinetic (PK) model describing the perioperative FIX levels. Population PK parameter values for clearance and V1 were 284 mL hâ170 kgâ1 and 5450 mL70 kgâ1. Perioperative PK parameters differ from those during non-surgical prophylactic treatment. Summary: Background Hemophilia B is a bleeding disorder characterized by a deficiency of coagulation factor IX (FIX). In the perioperative sett
One piece of the puzzle: Population pharmacokinetics of FVIII during perioperative Haemate PÂź/Humate PÂź treatment in von Willebrand disease patients
Introduction: Many patients with von Willebrand disease (VWD) are treated on demand with von Willebrand factor and factor VIII (FVIII) containing concentrates present with VWF and/or FVIII plasma levels outside set target levels. This carries a risk for bleeding and potentially for thrombosis. Development of a population pharmacokinetic (PK) model based on FVIII levels is a first step to more accurate on-demand perioperative dosing of this concentrate
Is pharmacokinetic-guided dosing of desmopressin and von Willebrand factor-containing concentrates in individuals with von Willebrand disease or low von Willebrand factor reliable and feasible? A protocol for a multicentre, non-randomised, open label cohort trial, the OPTI-CLOT: To WiN study
Introduction Von Willebrand disease (VWD) is a bleeding disorder, caused by a deficiency or defect of von Willebrand factor (VWF). In case of medical procedures or bleeding, patients are treated with desmopressin and/or VWF-containing concentrates to increase plasma VWF and factor VIII (FVIII). However, in many cases these factor levels are outside the targeted range. Therefore, population pharmacokinetic (PK) models have been developed, which aim to quantify and explain intraindividual and interindividual differences in treatment response. These models enable calculation of individual PK parameters by Bayesian analysis, based on an individual desmopressin test or PK profile with a VWF-containing concentrate. Subsequently, the dose necessary for an individual to achieve coagulation factor target levels can be calculated. Methods and analysis Primary aim of this study is to assess the predictive performance (the difference between predicted and measured von VWF activity and FVIII levels) of Bayesian forecasting using the developed population PK models in four different situations: (A) desmopressin testing (nâ„30); (B) medical procedures (n=70; 30 receiving desmopressin, 30 receiving VWF-containing concentrate and 10 receiving a combination of both); (C) bleeding episodes (n=20; 10 receiving desmopressin and 10 receiving VWF-containing concentrate) and (D) prophylaxis with a VWF-containing concentrate (n=3 to 5). Individuals with all types of VWD and individuals with low VWF (VWF 0.30-0.60 IU/mL) will be included. Reliability and feasibility of PK-guided dosing will be tested by assessing predictive performance, treatment duration, haemostasis, patient satisfaction and physician satisfaction. Ethics and dissemination The OPTI-CLOT:to WiN study was approved by the medical ethics committee of the Erasmus MC, University Medical Centre Rotterdam, the Netherlands. Results of the study will be communicated through publication in international scientific journals and presentation at (inter)national conferences. Trial registration number NL7212 (NTR7411); Pre-results, EudraCT 2018-001631-46
Caloric Restriction Protects against Lactacystin-Induced Degeneration of Dopamine Neurons Independent of the Ghrelin Receptor
Parkinsonâs disease (PD) is a neurodegenerative disorder, characterized by a loss of dopamine (DA) neurons in the substantia nigra pars compacta (SNc). Caloric restriction (CR) has been shown to exert ghrelin-dependent neuroprotective effects in the 1-methyl-4-phenyl-1,2,3,6-tetrathydropyridine (MPTP)-based animal model for PD. We here investigated whether CR is neuroprotective in the lactacystin (LAC) mouse model for PD, in which proteasome disruption leads to the destruction of the DA neurons of the SNc, and whether this effect is mediated via the ghrelin receptor. Adult male ghrelin receptor wildtype (WT) and knockout (KO) mice were maintained on an ad libitum (AL) diet or on a 30% CR regimen. After 3 weeks, LAC was injected unilaterally into the SNc, and the degree of DA neuron degeneration was evaluated 1 week later. In AL mice, LAC injection significanty reduced the number of DA neurons and striatal DA concentrations. CR protected against DA neuron degeneration following LAC injection. However, no differences were observed between ghrelin receptor WT and KO mice. These results indicate that CR can protect the nigral DA neurons from toxicity related to proteasome disruption; however, the ghrelin receptor is not involved in this effect
3D printed ceramics:: Exploring the experiential material characteristics and the freedom of additive manufacturing
This master thesis is a graduation project of the master study Integrated Product Design at Delft University of Technology. It was executed in collaboration with the Material Experience Lab in the faculty Industrial Design Engineering. The project follows the Material Driven Design method by Elvin Karana. The material being researched is the Formlabs ceramic resin which was newly developed and has been on the market for approximately a year now. The Formlabs ceramic resin is a 3D printable ceramic material which uses photopolymerization to solidify the resin into objects. The material requires extra steps and experimenting and is now mostly used in educational and researching environments, because of the challenges it brings. These challenges mainly occur because not enough is known about the material and the way of use. However, the Formlabs material has a great potential of being more user friendly and easier to use than other 3D printable ceramic materials. This is because the material is made for the specific 3D printer allowing them to work together perfectly, increasing the ease of use and success rate. The main research question for this thesis is: Which technical and experiential material properties should be emphasized to create unique material-user experiences? The research started with understanding the material by executing user studies, technical tests and by conducting many tinkering experiments. The tinkering process was based on the information provided by Formlabs. These experiments and tests led to several insights which created a clear overview of unique and interesting material characteristics. User studies concluded that the material was perceived as rough and tactually offensive but as pure, inviting and aesthetically pleasing because of the mat white colour, translucency and lack of impurities, creating a sensorial incongruence. Some interesting directions came forth out of the tinkering phase and the user studies. It is possible to create controlled cracks in the walls of objects. Another interesting opportunity is the possibility to produce hidden Internal structures which play with the translucency of the material. This is possible because of the high precision 3D printing technique used. Lastly digitally modified surface textures can be created which alter the tactual experience of the material. The translucency of the material and the possibility of digitally modified surface textures were further explored during this project. It was concluded from user studies that people experienced textures inspired by nature as more tactually pleasing. Furthermore, the translucency of the material allows for light to add depth to the more dimensional textures making the experience even more pleasing. An envisioned material experience was formulated by combining the findings and insights from the tinkering process. The envisioned role of the material was to attract people and invite and encourage them to interact with the object by touching and holding the surface. The tactile stimulation experienced is pleasant because of the digitally modified surface texture. When interacting with the object a hidden feature becomes visible emphasizing the translucency of the material. This hidden feature will showcase the opportunities 3D printing of translucent ceramics brings. User studies and an ideation session was held in order to materialise and realise this envisioned experience. This ideation resulted in a design direction: Design a product set or a product made up out of different components, which initially look identical but become distinguishable when a hidden feature is unveiled, by emphasizing the materialâs translucency. The final product concept came to be a interactive table lamp which encourages people to explore the effects of light on the material. The lamps has digitally modified surface textures which remove the original tactile offensiveness, creating a pleasant tactile experience. It is also made up out of different components which look identical until the lamp is turned on, unveiling hidden textures.Integrated Product Desig