A Framework for Test & Evaluation of Autonomous Systems Along the Virtuality-Reality Spectrum

Test & Evaluation of autonomous vehicles presents a challenge as the vehicles may have emergent behavior and it is frequently difficult to ascertain the reason for software decisions. Current Test & Evaluation approaches for autonomous systems place the vehicles in various operating scenarios to observe their behavior. However, this introduces dependencies between design and development lifecycle of the autonomous software and physical vehicle hardware. Simulation-based testing can alleviate the necessity to have physical hardware; however, it can be costly when transitioning the autonomous software to and from a simulation testing environment. The objective of this thesis is to develop a reusable framework for testing autonomous software such that testing can be conducted at various levels of mixed reality provided the framework components are sufficient to support data required by the autonomous software. The paper describes the design of the software framework and explores its application through use cases

TEACHER´S DIDACTIC COMPETENCIES WHEN TEACHING NATURAL SCIENCE SUBJECTS AS A LEARNING ENVIRONMENT FACTOR

The relationship of primary and secondary schools pupils to natural science subjects is often discussed together with teacher´s didactic competencies that are implemented when teaching natural science subjects. The aim of the paper is to find out how pupils from chosen primary and secondary schools in the Slovak Republic evaluate didactic competencies of natural science subjects teachers in the framework of the overall learning environment evaluation of these subjects. The means to fulfil this objective is the analysis of corresponding questionnaire items oriented on the learning environment when teaching natural science subjects. A partial aim is to compare the evaluation of natural science teachers didactic competencies from several points of view: school type (at primary and secondary schools), gender issues (boys and girls), in relation to the overall learning environment and in relation to learning environment at primary and secondary schools.  Article visualizations

Centrifugal adsorption system

A gas-liquid separator uses a helical passageway to impart a spiral motion to a fluid passing therethrough. The centrifugal force generated by the spiraling motion urges the liquid component of the fluid radially outward which forces the gas component radially inward. The gas component is then separated through a gas-permeable, liquid-impervious membrane and discharged through a central passageway. A filter material captures target substances contained in the fluid

Fluid bubble eliminator

A gas-liquid separator uses a helical passageway to impart a spiral motion to a fluid passing therethrough. The centrifugal fore generated by the spiraling motion urges the liquid component of the fluid radially outward which forces the gas component radially inward. The gas component is then filtered through a gas-permeable, liquid-impervious membrane and discharged through a central passageway

Performance of sweet cherry cultivars grafted on Colt rootstock

In this paper growing characteristics and fruit bearing parameters of ‘Lapins’, ‘Kordia’, ‘Sweetheart’ and ‘Regina’ sweet cherry cultivars grafted on vigorous Colt rootstock were evaluated at the University of Debrecen, Pallag Experimental Station. Based on our data five years old trees can be described with homogenous strong growing, but very week yielding (2.1-3.1 kg/tree), as while fruit size varies between 26.2 and 27.2 mm. Producing the examined cultivars on Colt rootstock with high plant density requires higher attention and more interventions (root pruning, sawing the trunk) during the technology

Centrifugal Adsorption Cartridge System

The centrifugal adsorption cartridge system (CACS) is an apparatus that recovers one or more bioproduct(s) from a dilute aqueous solution or suspension flowing from a bioreactor. The CACS can be used both on Earth in unit gravity and in space in low gravity. The CACS can be connected downstream from the bioreactor; alternatively, it can be connected into a flow loop that includes the bioreactor so that the liquid can be recycled. A centrifugal adsorption cartridge in the CACS (see figure) includes two concentric cylinders with a spiral ramp between them. The volume between the inner and outer cylinders, and between the turns of the spiral ramp is packed with an adsorbent material. The inner cylinder is a sieve tube covered with a gas-permeable, hydrophobic membrane. During operation, the liquid effluent from the bioreactor is introduced at one end of the spiral ramp, which then constrains the liquid to flow along the spiral path through the adsorbent material. The spiral ramp also makes the flow more nearly uniform than it would otherwise be, and it minimizes any channeling other than that of the spiral flow itself. The adsorbent material is formulated to selectively capture the bioproduct(s) of interest. The bioproduct(s) can then be stored in bound form in the cartridge or else eluted from the cartridge. The centrifugal effect of the spiral flow is utilized to remove gas bubbles from the liquid. The centrifugal effect forces the bubbles radially inward, toward and through the membrane of the inner cylinder. The gas-permeable, hydrophobic membrane allows the bubbles to enter the inner cylinder while keeping the liquid out. The bubbles that thus enter the cylinder are vented to the atmosphere. The spacing between the ramps determines rate of flow along the spiral, and thereby affects the air-bubble-removal efficiency. The spacing between the ramps also determines the length of the fluid path through the cartridge adsorbent, and thus affects the bioproduct-capture efficiency of the cartridge. Depending on the application, several cartridges could be connected in a serial or parallel flow arrangement. A parallel arrangement can be used to increase product-capturing and flow capacities while maintaining a low pressure drop. A serial arrangement can be used to obtain high product-capturing capacity; alternatively, series-connected cartridges can be packed with different adsorbents to capture different bioproducts simultaneously

In vitro and ex vivo methods predict the enhanced lung residence time of liposomal ciprofloxacin formulations for nebulisation

Liposomal ciprofloxacin formulations have been developed with the aim of enhancing lung residence time, thereby reducing the burden of inhaled antimicrobial therapy which requires multiple daily administration due to rapid absorptive clearance of antibiotics from the lungs. However, there is a lack of a predictive methodology available to assess controlled release inhalation delivery systems and their effect on drug disposition. In this study, three ciprofloxacin formulations were evaluated: a liposomal formulation, a solution formulation and a 1:1 combination of the two (mixture formulation). Different methodologies were utilised to study the release profiles of ciprofloxacin from these formulations: (i) membrane diffusion, (ii) air interface Calu-3 cells and (iii) isolated perfused rat lungs. The data from these models were compared to the performance of the formulations in vivo. The solution formulation provided the highest rate of absorptive transport followed by the mixture formulation, with the liposomal formulation providing substantially slower drug release. The rank order of drug release/transport from the different formulations was consistent across the in vitro andex vivo methods, and this was predictive of the profiles in vivo. The use of complimentary in vitro and ex vivo methodologies provided a robust analysis of formulation behaviour, including mechanistic insights, and predicted in vivo pharmacokinetics.© 2013 Elsevier B.V. All rights reserved

Inhaled Liposomal Ciprofloxacin Nanoparticles Control the Release of Antibiotic at the Bronchial Epithelia

The cycle of respiratory tract infection (RTI) and inflammation in patients with chronic obstructive lung diseases, such as cystic fibrosis (CF), periodically develops into exacerbations, where chronic colonization of the airway by bacteria causes severe decline in lung function, leading to increased hospitalization and high mortality rates (1, 2). Current antibiotic inhalation treatments approved for the management of chronic airway infections in cystic fibrosis are limited to tobramycin (TOBI®) and more recently, aztreonam (Cayston®). A major drawback to these localized treatments of RTIs is the rapid absorption and clearance of antibiotics from the lungs requiring multiple daily inhalations of high concentration antibiotic solutions. Hence, liposomal ciprofloxacin nanoparticles were developed to prolong lung residence time of the antibiotics, with the view to enhance antimicrobial activity and reduce the burden of therapy for the patients and their relatives who often have to assist them. Although in vivo studies with aerosolized delivery of liposomal ciprofloxacin have previously been performed on human and animal subjects, in vitro cell models may be better suited to study the transport, interactions of drugs and carrier systems, and drug localization within and on the airway cell epithelium at a molecular level. Therefore, the aim of this study was to investigate the newly developed system allowing nebulized liposomal ciprofloxacin to be delivered directly to the bronchial epithelial surface in an established air interface Calu-3 cell model

Hydrofocusing Bioreactor for Three-Dimensional Cell Culture

The hydrodynamic focusing bioreactor (HFB) is a bioreactor system designed for three-dimensional cell culture and tissue-engineering investigations on orbiting spacecraft and in laboratories on Earth. The HFB offers a unique hydrofocusing capability that enables the creation of a low-shear culture environment simultaneously with the "herding" of suspended cells, tissue assemblies, and air bubbles. Under development for use in the Biotechnology Facility on the International Space Station, the HFB has successfully grown large three-dimensional, tissuelike assemblies from anchorage-dependent cells and grown suspension hybridoma cells to high densities. The HFB, based on the principle of hydrodynamic focusing, provides the capability to control the movement of air bubbles and removes them from the bioreactor without degrading the low-shear culture environment or the suspended three-dimensional tissue assemblies. The HFB also provides unparalleled control over the locations of cells and tissues within its bioreactor vessel during operation and sampling