Object grouping in EOS

Projet RODINEos is an environment for building distributed object-based systems. Leos, the language for Eos, provides transparency for distribution and persistence. In this paper, we address the problem of declustering the object graph into a number of nodes and of locally clustering objects within pages with minimal impact on the programming process. We propose a grouping model which on the one hand achieves full transparency. The grouping is dynamically achieved by the run-time system as directed by user-provided hints. This dynamic object grouping copes automatically with evolutions of the object graph. The implementation incurs little overhead it is a side-effect of garbage collection. On the other hand, our model supplies Eos users with an explicit and fine control over data and computation placement so they can load balance the overall system

Efficient nested locking in EOS

Projet RODINRésumé disponbile dans le ficheir PD

Efficient Incremental Garbage Collection for Workstation/Server Database Systems

Projet RODINWe describe an efficient server-based algorithm for garbage collecting object-oriented databases in a workstation/server environment. The algorithm is incremental and runs concurrently with client transactions, however, it does not hold any locks on data and does not require callbacks to clients. It is fault tolerant, but performs very little logging. The algorithm has been designed to be integrated into existing OODB systems, and therefore it works with standard implementation techniques such as two-phase locking and write-ahead-logging. In addition, it supports client-server performance optimizations such as client caching and flexible management of client buffers. We describe an implementation of the algorithm in the EXODUS storage manager and present results from an initial performance study of the implementation. These results demonstrate that the introduction of the garbage collector adds minimal overhead to client operations

EOS, an environnement for object-based systems

Projet RODINRésumé disponible dans le fichier PD

Barriers for Sports and Exercise Participation and Corresponding Barrier Management in Cystic Fibrosis

Background Nowadays physical activity (PA)/exercise is an important component of cystic fibrosis (CF) therapy. The aim of the study was to assess the barriers to PA and the barrier management and to explore the effect of supervision on the barriers and barrier management during an exercise program. Methods In total, 88 people with CF (pwCF) of the ages 6 to 50 years old (mean 24.2 ± 7.9 yrs) participated in the partially supervised 12-month exercise program and filled in a structured and validated questionnaire about barriers to sports and barrier management at baseline. Results Physical barriers were more relevant than psychosocial barriers and no trend could be seen in the situational and preventive counter strategies. When divided in subgroups, the less active pwCF (7500 steps/day), physical barriers, and psychosocial barriers showed no significant differences. However physical barriers showed a tendency to have a higher value in the less active group compared to the more active group (p > 0.05). Stratified by age or FEV1%pred between the subgroups, no differences could be seen regarding barriers and counter strategies. Conclusions Physical barriers seemed to have a higher priority when it comes to not participating in PA/exercise. Supervision over 6 months during an exercise program did not show a beneficial effect on barriers and barrier management. Besides the motivational aspect of sport counselling, the volitional aspect seemed to be more important to incorporate more PA into daily life. Individual barriers and their concrete counter strategies should be discussed with the patient with CF. Sport counselling is needed permanently and should be part of the CF routine care

Polymer architecture as key to unprecedented high-resolution 3D-printing performance : the case of biodegradable hexa-functional telechelic urethane-based poly-ε-caprolactone

Two-photon polymerization (2PP) is a high-resolution 3D-printing technology with a very rapidly expanding field of applications, including tissue engineering (TE). In this field, 2PP offers unprecedented possibilities for systematic studies of both cell–cell and cell–material interactions in 3D. For TE applications, the reliable production of biodegradable micro-scaffolds in porous, complex architectures is essential. However, the number of biodegradable materials that support the required level of spatial resolution is very limited, being a major bottleneck for the use of 2PP in the TE field. Herein, we introduce a hexa-functional urethane-based biodegradable precursor that overcomes the limitations associated with the high-resolution printing of current biodegradable precursors. The precursor is a telechelic urethane-based poly-ε-caprolactone (PCL) possessing three acrylate functionalities at each polymer end group which enables the reliable production of complex architectures owing to its superior physical properties as compared to the traditional di-acrylate terminated analogs. The newly developed hexa-functional telechelic urethane-based PCL reveals enhanced crosslinking kinetics and one order of magnitude higher Young’s modulus compared to the di-functional precursor (57.8 versus 6.3 MPa), providing an efficient and solvent-free 2PP processing at fast scanning speeds of up to 100 mm s−1 with unprecedented feature resolutions (143 ± 18 nm at 100 mm s−1 scanning speed). The crosslinked hexa-functional polymer combines strength and flexibility owing to the segregation between its hard polyacrylate and soft PCL segments, which makes it suitable for biological systems in contrast to the highly crosslinked and rigid structures typically manufactured by 2PP. Furthermore, it revealed lower degradation rate compared to its di-functional analog, which can be considered as an advantage in terms of biocompatibility due to the slower formation of acidic degradation products. Extracts of the developed polymers did not show a cytotoxic effect on the L929 fibroblasts as confirmed via ISO 10993-5 standard protocol. The presented precursor design constitutes a simple and effective approach that can be easily translated towards other biodegradable polymers for the manufacturing of biodegradable constructs with nano-scale precision, offering for the first time to use the true capabilities of 2PP for TE applications with the use of synthetic biodegradable polymers

ROOT for the HL-LHC: data format

This document discusses the state, roadmap, and risks of the foundational components of ROOT with respect to the experiments at the HL-LHC (Run 4 and beyond). As foundational components, the document considers in particular the ROOT input/output (I/O) subsystem. The current HEP I/O is based on the TFile container file format and the TTree binary event data format. The work going into the new RNTuple event data format aims at superseding TTree, to make RNTuple the production ROOT event data I/O that meets the requirements of Run 4 and beyond

Sequence–structure relationships in yeast mRNAs

It is generally accepted that functionally important RNA structure is more conserved than sequence due to compensatory mutations that may alter the sequence without disrupting the structure. For small RNA molecules sequence–structure relationships are relatively well understood. However, structural bioinformatics of mRNAs is still in its infancy due to a virtual absence of experimental data. This report presents the first quantitative assessment of sequence–structure divergence in the coding regions of mRNA molecules based on recently published transcriptome-wide experimental determination of their base paring patterns. Structural resemblance in paralogous mRNA pairs quickly drops as sequence identity decreases from 100% to 85–90%. Structures of mRNAs sharing sequence identity below roughly 85% are essentially uncorrelated. This outcome is in dramatic contrast to small functional non-coding RNAs where sequence and structure divergence are correlated at very low levels of sequence similarity. The fact that very similar mRNA sequences can have vastly different secondary structures may imply that the particular global shape of base paired elements in coding regions does not play a major role in modulating gene expression and translation efficiency. Apparently, the need to maintain stable three-dimensional structures of encoded proteins places a much higher evolutionary pressure on mRNA sequences than on their RNA structures