Highlighting type A RRs as potential regulators of the dkHK1 multi-step phosphorelay pathway in Populus

In previous studies, we highlighted a multistep phosphorelay (MSP) system in poplars composed of two hybrid-type Histidine aspartate Kinases, dkHK1a and dkHK1b, which interact with three Histidine Phosphotransfer proteins, dkHPt2, 7, and 9, which in turn interact with six type B Response Regulators. These interactions correspond to the dkHK1a-b/dkHPts/dkRRBs MSP. This MSP is putatively involved in an osmosensing pathway, as dkHK1a-b are orthologous to the Arabidopsis osmosensor AHK1, and able to complement a mutant yeast deleted for its osmosensors. Since type A RRs have been characterized as negative regulators in cytokinin MSP signaling due to their interaction with HPt proteins, we decided in this study to characterize poplar type A RRs and their implication in the MSP. For a global view of this MSP, we isolated 10 poplar type A RR cDNAs, and determined their subcellular localization to check the in silico prediction experimentally. For most of them, the in planta subcellular localization was as predicted, except for three RRAs, for which this experimental approach gave a more precise localization. Interaction studies using yeast two-hybrid and in planta BiFC assays, together with transcript expression analysis in poplar organs led to eight dkRRAs being singled out as partners which could interfere the dkHK1a-b/dkHPts/dkRRBs MSP identified in previous studies. Consequently, the results obtained in this study now provide an exhaustive view of dkHK1a-b partners belonging to a poplar MSP

The use of intelligent simulation in cost-time forecasts for housing rehabilitation works

The research aimed to investigate the feasibility of using intelligent simulation for construction cost-time forecasting in order to provide an aid to strategic decision-making in housing rehabilitation work. Essential features were anticipated as being the provision of probabilistic forecasts and the ability to reflect the operational consequences of alternative design and management strategies.\ud \ud The intelligent simulation envisaged was essentially a hybrid of stochastic simulation and knowledge based systems such that:\ud \ud • an operational plan for the project would be generated automatically by the system, using knowledge drawn from expert planners;\ud \ud • stochastic simulation would be used to evaluate project time and cost from the production plan, thus providing probabilistic forecasts;\ud \ud • site management control of the production process would be emulated by interaction of the simulation with a knowledge base representing the expertise of the site managers;\ud \ud • a graphics-based user interface would permit real time monitoring and interaction with the simulation.\ud \ud Low-rise multiple-unit housing rehabilitation projects of a clearly defined type were used as the vehicle for this investigation, as these projects are characterised by high levels of uncertainty and sensitivity of cost and time to operational factors.\ud \ud The approach adopted was to seek to build a trial system or concept demonstrator. As the aim was to investigate feasibility, no attempt was made to acquire full domain knowledge, effort being concentrated upon establishing the structure and nature of the knowledge to be encapsulated, and determining appropriate methods of knowledge representation and system architecture. Conceptual design of the system was completed within the grant period, but some work remains to be done to achieve an operational concept demonstrator.\ud \ud The main findings were as follows:\ud \ud System design\ud \ud 1. A system integrating knowledge-based approaches with stochastic simulation is readily achievable within an object-oriented structure.\ud \ud 2. Automatic operational planning for repetitive works of these kind is also readily achievable, within an object oriented structure.\ud \ud Knowledge acquisition\ud \ud 3. The domain of planning expertise examined proved suitable for KBS development. The techniques and heuristics employed are well established and consensus between experts is strong.\ud \ud 4. The domain of site management expertise presented problems; this knowledge appears difficult to both acquire and represent. Only limited progress was made with the simple and direct knowledge elicitation techniques used: there is some evidence that more sophisticated indirect techniques may perform better but it was not possible to test this within the grant period.\ud \ud 5. The experts in housing rehabilitation that were consulted strongly reinforced the view that there is a real need for tools to support both strategic decision making and planning on this type of project.\ud \ud 1. Feasibility of the intelligent simulation approach\ud \ud 6. The research indicated that current levels of hardware and software technology are capable of supporting the development of a working intelligent simulation-based construction cost and time forecasting system, where:\ud \ud • an object-oriented structure is adopted;\ud \ud • the construction projects involved are repetitive, multiple-unit schemes of a type for which a well established body of planning expertise exists;\ud \ud • the variety of construction work to be handled by the system is limited;\ud \ud • a very limited and crude representation of site management control decisions and actions is acceptable

The use of intelligent simulation in cost-time forecasts for housing rehabilitation works

The research aimed to investigate the feasibility of using intelligent simulation for construction cost-time forecasting in order to provide an aid to strategic decision-making in housing rehabilitation work. Essential features were anticipated as being the provision of probabilistic forecasts and the ability to reflect the operational consequences of alternative design and management strategies. The intelligent simulation envisaged was essentially a hybrid of stochastic simulation and knowledge based systems such that: • an operational plan for the project would be generated automatically by the system, using knowledge drawn from expert planners; • stochastic simulation would be used to evaluate project time and cost from the production plan, thus providing probabilistic forecasts; • site management control of the production process would be emulated by interaction of the simulation with a knowledge base representing the expertise of the site managers; • a graphics-based user interface would permit real time monitoring and interaction with the simulation. Low-rise multiple-unit housing rehabilitation projects of a clearly defined type were used as the vehicle for this investigation, as these projects are characterised by high levels of uncertainty and sensitivity of cost and time to operational factors. The approach adopted was to seek to build a trial system or concept demonstrator. As the aim was to investigate feasibility, no attempt was made to acquire full domain knowledge, effort being concentrated upon establishing the structure and nature of the knowledge to be encapsulated, and determining appropriate methods of knowledge representation and system architecture. Conceptual design of the system was completed within the grant period, but some work remains to be done to achieve an operational concept demonstrator. The main findings were as follows: System design 1. A system integrating knowledge-based approaches with stochastic simulation is readily achievable within an object-oriented structure. 2. Automatic operational planning for repetitive works of these kind is also readily achievable, within an object oriented structure. Knowledge acquisition 3. The domain of planning expertise examined proved suitable for KBS development. The techniques and heuristics employed are well established and consensus between experts is strong. 4. The domain of site management expertise presented problems; this knowledge appears difficult to both acquire and represent. Only limited progress was made with the simple and direct knowledge elicitation techniques used: there is some evidence that more sophisticated indirect techniques may perform better but it was not possible to test this within the grant period. 5. The experts in housing rehabilitation that were consulted strongly reinforced the view that there is a real need for tools to support both strategic decision making and planning on this type of project. 1. Feasibility of the intelligent simulation approach 6. The research indicated that current levels of hardware and software technology are capable of supporting the development of a working intelligent simulation-based construction cost and time forecasting system, where: • an object-oriented structure is adopted; • the construction projects involved are repetitive, multiple-unit schemes of a type for which a well established body of planning expertise exists; • the variety of construction work to be handled by the system is limited; • a very limited and crude representation of site management control decisions and actions is acceptable

Evaluation of type-B RR dimerization in poplar: A mechanism to preserve signaling specificity?

International audienc

Deleterious effect of suboptimal diet on rest-activity cycle in Anastrepha ludens manifests itself with age

Activity patterns and sleep-wake cycles are among the physiological processes that change most prominently as animals age, and are often good indicators of healthspan. In this study, we used the video-based high-resolution Behavioral Monitoring System (BMS) to monitor the daily activity cycle of tephritid fruit flies Anastrepha ludens over their lifetime. Surprisingly, there was no dramatic change in activity profile with respect to age if flies were consistently fed with a nutritionally balanced diet. However, if flies were fed with sugar-only diet, their activity profile decreased in amplitude at old age, suggesting that suboptimal diet affected activity patterns, and its detrimental effect may not manifest itself until the animal ages. Moreover, by simulating different modes of behavior monitoring with a range of resolution and comparing the resulting conclusions, we confirmed the superior performance of video-based monitoring using high-resolution BMS in accurately representing activity patterns in an insect model

Reliability and variability of sleep and activity as biomarkers of ageing in Drosophila

There are currently no reliable biomarkers of ageing. A biomarker should indicate biological age, that is, the amount of an animal's total lifespan it has lived and, therefore, the amount of time it has remaining. Some potential biomarkers cannot be validated as their measurement involves harm or death of the animal, such that its ultimate lifespan cannot be determined. A non-destructive biomarker would allow us to test molecular markers potentially involved directly in the ageing process, to monitor the effectiveness of therapeutic interventions to delay ageing, and provide a useful measure of general health of the organism. In the model organism Drosophila, various behavioural phenotypes change directionally with age, but we do not know whether they predict lifespan. Here we measure activity and sleep parameters in 64 wild type male flies from two recently wild-caught populations over the course of their natural lives, and determine whether such measures may predict biological age and ultimate lifespan. Indices of sleep fragmentation and circadian rhythm were the best predictors of lifespan, though population differences were evident. However, when used to predict a biological age of 50 % lifespan elapsed our best behavioural measure was slightly less accurate and less precise compared with using chronological age as predictor