The Middeck Active Control Experiment (MACE)

The Middeck Active Control Experiment (MACE) is a NASA In-Step and Control Structure Interaction (CSI) Office funded Shuttle middeck experiment. The objective is to investigate the extent to which closed-loop behavior of flexible spacecraft in zero-gravity (0-g) can be predicted. This prediction becomes particularly difficult when dynamic behavior during ground testing exhibits extensive suspension and direct gravity coupling. On-orbit system identification and control reconfiguration is investigated to improve performance which would otherwise be limited due to errors in prediction. The program is presently in its preliminary design phase with launch expected in the summer of 1994. The MACE test article consists of three attitude control torque wheels, a two axis gimballing payload, inertial sensors and a flexible support structure. With the acquisition of a second payload, this will represent a multiple payload platform with significant structural flexibility. This paper presents on-going work in the areas of modelling and control of the MACE test article in the zero and one-gravity environments. Finite element models, which include suspension and gravity effects, and measurement models, derived from experimental data, are used as the basis for Linear Quadratic Gaussian controller designs. Finite element based controllers are analytically used to study the differences in closed-loop performance as the test article transitions between the 0-g and 1-g environments. Measurement based controllers are experimentally applied to the MACE test article in the 1-g environment and achieve over an order of magnitude improvement in payload pointing accuracy when disturbed by a broadband torque disturbance. The various aspects of the flight portion of the experiment are also discussed

Soil and water bioengineering: practice and research needs for reconciling natural hazard control and ecological restoration

Soil and water bioengineering is a technology that encourages scientists and practitioners to combine their knowledge and skills in the management of ecosystems with a common goal to maximize benefits to both man and the natural environment. It involves techniques that use plants as living building materials, for: (i) natural hazard control (e.g., soil erosion, torrential floods and landslides) and (ii) ecological restoration or nature-based re-introduction of species on degraded lands, river embankments, and disturbed environments. For a bioengineering project to be successful, engineers are required to highlight all the potential benefits and ecosystem services by documenting the technical, ecological, economic and social values. The novel approaches used by bioengineers raise questions for researchers and necessitate innovation from practitioners to design bioengineering concepts and techniques. Our objective in this paper, therefore, is to highlight the practice and research needs in soil and water bioengineering for reconciling natural hazard control and ecological restoration. Firstly, we review the definition and development of bioengineering technology, while stressing issues concerning the design, implementation, and monitoring of bioengineering actions. Secondly, we highlight the need to reconcile natural hazard control and ecological restoration by posing novel practice and research questions

Towards the understanding of the cocoa transcriptome: Production and analysis of an exhaustive dataset of ESTs of Theobroma cacao L. generated from various tissues and under various conditions

Theobroma cacao L., is a tree originated from the tropical rainforest of South America. It is one of the major cash crops for many tropical countries. T. cacao is mainly produced on smallholdings, providing resources for 14 million farmers. Disease resistance and T. cacao quality improvement are two important challenges for all actors of cocoa and chocolate production. T. cacao is seriously affected by pests and fungal diseases, responsible for more than 40% yield losses and quality improvement, nutritional and organoleptic, is also important for consumers. An international collaboration was formed to develop an EST genomic resource database for cacao. Fifty-six cDNA libraries were constructed from different organs, different genotypes and different environmental conditions. A total of 149,650 valid EST sequences were generated corresponding to 48,594 unigenes, 12,692 contigs and 35,902 singletons. A total of 29,849 unigenes shared significant homology with public sequences from other species. Gene Ontology (GO) annotation was applied to distribute the ESTs among the main GO categories. A specific information system (ESTtik) was constructed to process, store and manage this EST collection allowing the user to query a database. To check the representativeness of our EST collection, we looked for the genes known to be involved in two different metabolic pathways extensively studied in other plant species and important for T. cacao qualities: the flavonoid and the terpene pathways. Most of the enzymes described in other crops for these two metabolic pathways were found in our EST collection. A large collection of new genetic markers was provided by this ESTs collection. This EST collection displays a good representation of the T. cacao transcriptome, suitable for analysis of biochemical pathways based on oligonucleotide microarrays derived from these ESTs. It will provide numerous genetic markers that will allow the construction of a high density gene map of T. cacao. This EST collection represents a unique and important molecular resource for T. cacao study and improvement, facilitating the discovery of candidate genes for important T. cacao trait variation. (Résumé d'auteur

O stars with weak winds: the Galactic case

We study the stellar and wind properties of a sample of Galactic O dwarfs to track the conditions under which weak winds (i.e mass loss rates lower than ~ 1e-8 Msol/yr) appear. The sample is composed of low and high luminosity dwarfs including Vz stars and stars known to display qualitatively weak winds. Atmosphere models including non-LTE treatment, spherical expansion and line blanketing are computed with the code CMFGEN. Both UV and Ha lines are used to derive wind properties while optical H and He lines give the stellar parameters. Mass loss rates of all stars are found to be lower than expected from the hydrodynamical predictions of Vink et al. (2001). For stars with log L/Lsol > 5.2, the reduction is by less than a factor 5 and is mainly due to the inclusion of clumping in the models. For stars with log L/Lsol < 5.2 the reduction can be as high as a factor 100. The inclusion of X-ray emission in models with low density is crucial to derive accurate mass loss rates from UV lines. The modified wind momentum - luminosity relation shows a significant change of slope around this transition luminosity. Terminal velocities of low luminosity stars are also found to be low. The physical reason for such weak winds is still not clear although the finding of weak winds in Galactic stars excludes the role of a reduced metallicity. X-rays, through the change in the ionisation structure they imply, may be at the origin of a reduction of the radiative acceleration, leading to lower mass loss rates. A better understanding of the origin of X-rays is of crucial importance for the study of the physics of weak winds.Comment: 31 pages, 42 figures. A&A accepted. A version of the paper with full resolution figures is available at http://www.mpe.mpg.de/~martins/publications.htm

PSORTb 3.0: improved protein subcellular localization prediction with refined localization subcategories and predictive capabilities for all prokaryotes

Motivation: PSORTb has remained the most precise bacterial protein subcellular localization (SCL) predictor since it was first made available in 2003. However, the recall needs to be improved and no accurate SCL predictors yet make predictions for archaea, nor differentiate important localization subcategories, such as proteins targeted to a host cell or bacterial hyperstructures/organelles. Such improvements should preferably be encompassed in a freely available web-based predictor that can also be used as a standalone program

Learning Styles and Technology Implementation of Special Education Teachers in the New Normal

This research evaluates special education teachers' learning styles and technological implementation at SpEd Schools in Mandaue City, Cebu, and Kananga Leyte, both in the Philippines, during the school year 2020–2021. It aimed to determine the Special Education Teachers' learning styles as well as the status of technology implementation of new learning modes during a pandemic. Because of the new setup for the educational platform in Special Education, this research also sought to gather information on the numerous concerns and problems associated with technology deployment, as well as the essential support and assistance in addressing such challenges. This study used a mixed-methods approach. A survey design will be used in quantitative research. Qualitative research, on the other hand, will employ a pragmatic qualitative research approach. Respondents in this study included twenty (20) Special Education Teachers from Mandaue City Central SpEd School - Elementary, ten (10) Special Education Teachers from Mandaue City Central SpEd School - High School, and twenty (20) Special Education Teachers from Kananga Central School. They answered the modified survey form as well as the interview. Frequency count and percentage, weighted mean and standard deviation, Chi-square test of independence, and theme analysis are among the statistical treatments applied to the data. The majority of Special Education teachers are reasonable, proactive, spontaneous, and clear, according to the data. It establishes that computer technology is commonly used for organizational and educational purposes. In general, it shows that a teacher's profile has a significant link to their learning styles, level of technological integration, and process integration. The creation of an intervention strategy is proposed as a solution to this problem

Learning Styles and Technology Implementation of Special Education Teachers in the New Normal

This research evaluates special education teachers' learning styles and technological implementation at SpEd Schools in Mandaue City, Cebu, and Kananga Leyte, both in the Philippines, during the school year 2020–2021. It aimed to determine the Special Education Teachers' learning styles as well as the status of technology implementation of new learning modes during a pandemic. Because of the new setup for the educational platform in Special Education, this research also sought to gather information on the numerous concerns and problems associated with technology deployment, as well as the essential support and assistance in addressing such challenges. This study used a mixed-methods approach. A survey design will be used in quantitative research. Qualitative research, on the other hand, will employ a pragmatic qualitative research approach. Respondents in this study included twenty (20) Special Education Teachers from Mandaue City Central SpEd School - Elementary, ten (10) Special Education Teachers from Mandaue City Central SpEd School - High School, and twenty (20) Special Education Teachers from Kananga Central School. They answered the modified survey form as well as the interview. Frequency count and percentage, weighted mean and standard deviation, Chi-square test of independence, and theme analysis are among the statistical treatments applied to the data. The majority of Special Education teachers are reasonable, proactive, spontaneous, and clear, according to the data. It establishes that computer technology is commonly used for organizational and educational purposes. In general, it shows that a teacher's profile has a significant link to their learning styles, level of technological integration, and process integration. The creation of an intervention strategy is proposed as a solution to this problem

The Crystal Structure and RNA-Binding of an Orthomyxovirus Nucleoprotein

Genome packaging for viruses with segmented genomes is often a complex problem. This is particularly true for influenza viruses and other orthomyxoviruses, whose genome consists of multiple negative-sense RNAs encapsidated as ribonucleoprotein (RNP) complexes. To better understand the structural features of orthomyxovirus RNPs that allow them to be packaged, we determined the crystal structure of the nucleoprotein (NP) of a fish orthomyxovirus, the infectious salmon anemia virus (ISAV) (genus Isavirus). As the major protein component of the RNPs, ISAV-NP possesses a bi-lobular structure similar to the influenza virus NP. Because both RNA-free and RNA-bound ISAV NP forms stable dimers in solution, we were able to measure the NP RNA binding affinity as well as the stoichiometry using recombinant proteins and synthetic oligos. Our RNA binding analysis revealed that each ISAV-NP binds ,12 nts of RNA, shorter than the 24ﾖ28 nts originally estimated for the influenza A virus NP based on population average. The 12-nt stoichiometry was further confirmed by results from electron microscopy and dynamic light scattering. Considering that RNPs of ISAV and the influenza viruses have similar morphologies and dimensions, our findings suggest that NP-free RNA may exist on orthomyxovirus RNPs, and selective RNP packaging may be accomplished through direct RNA-RNA interactions

Subjective well-being indicators for large-scale assessment of cultural ecosystem services

The substantial importance of cultural benefits as a source of human well-being is increasingly recognised in society-environment interactions. The integration of cultural ecosystem services (CES) into the ecosystem services framework remains a challenge due to the difficulties associated with defining, articulating and measuring CES. We operationalise a novel framework developed by the UK National Ecosystem Assessment that identifies CES as the interactions between environmental spaces (i.e. physical localities or landscapes), and the activities that occur there. We evaluate the benefits of the CES provided by 151 UK marine sites to recreational sea anglers and divers, using subjective well-being indicators. Factor analysis of an online questionnaire with 1220 participants revealed multiple CES benefits that contribute to human wellbeing e.g. including ‘engagement with nature’, ‘place identity’ and ‘therapeutic value’. In addition to regional differences, we also found that biophysical attributes of sites, such as the presence of charismatic species and species diversity, were positively associated with provision of CES benefits. The study provides evidence that could be used to inform designation of protected areas. The indicators used in the study may also be adapted for use across a range of marine and terrestrial spaces for improved integration of CES in environmental decisionmaking