Strong Structural Controllability and Zero Forcing

In this chapter, we study controllability and output controllability of systems defined over graphs. Specifically, we consider a family of state-space systems, where the state matrix of each system has a zero/non-zero structure that is determined by a given directed graph. Within this setup, we investigate under which conditions all systems in this family are controllable, a property referred to as strong structural controllability. Moreover, we are interested in conditions for strong structural output controllability. We will show that the graph-theoretic concept of zero forcing is instrumental in these problems. In particular, as our first contribution, we prove necessary and sufficient conditions for strong structural controllability in terms of so-called zero forcing sets. Second, we show that zero forcing sets can also be used to state both a necessary and a sufficient condition for strong structural output controllability. In addition to these main results, we include interesting results on the controllability of subfamilies of systems and on the problem of leader selection.</p

The need for standardisation in life science research - an approach to excellence and trust

Today, academic researchers benefit from the changes driven by digital technologies and the enormous growth of knowledge and data, on globalisation, enlargement of the scientific community, and the linkage between different scientific communities and the society. To fully benefit from this development, however, information needs to be shared openly and transparently. Digitalisation plays a major role here because it permeates all areas of business, science and society and is one of the key drivers for innovation and international cooperation. To address the resulting opportunities, the EU promotes the development and use of collaborative ways to produce and share knowledge and data as early as possible in the research process, but also to appropriately secure results with the European strategy for Open Science (OS). It is now widely recognised that making research results more accessible to all societal actors contributes to more effective and efficient science; it also serves as a boost for innovation in the public and private sectors. However for research data to be findable, accessible, interoperable and reusable the use of standards is essential. At the metadata level, considerable efforts in standardisation have already been made (e.g. Data Management Plan and FAIR Principle etc.), whereas in context with the raw data these fundamental efforts are still fragmented and in some cases completely missing. The CHARME consortium, funded by the European Cooperation in Science and Technology (COST) Agency, has identified needs and gaps in the field of standardisation in the life sciences and also discussed potential hurdles for implementation of standards in current practice. Here, the authors suggest four measures in response to current challenges to ensure a high quality of life science research data and their re-usability for research and innovation

Specific gut microbial, biological, and psychiatric profiling related to binge eating disorders: A cross-sectional study in obese patients

Background & aimsBinge eating disorder (BED) is a frequent eating disorder associated with obesity and co-morbidities including psychiatric pathologies, which represent a big health burden on the society.The biological processes related to BED remain unknown. Based on psychological testing, anthropometry, clinical biology, gut microbiota analysis and metabolomic assessment, we aimed to examine the complex biological and psychiatric profile of obese patients with and without BED.MethodsPsychological and biological characteristics (anthropometry, plasma biology, gut microbiota, blood pressure) of 101 obese subjects from the Food4Gut cohort were analysed to decipher the differences between BED and Non BED patients, classified based on the Questionnaire for Eating Disorder Diagnosis (Q-EDD). Microbial 16S rDNA sequencing and plasma non-targeted metabolomics (liquid chromatography-mass spectrometry) were performed in a subcohort of 91 and 39 patients respectively.ResultsBED subjects exhibited an impaired affect balance, deficits in inhibition and self-regulation together with marked alterations of eating behaviour (increased emotional and external eating). BED subjects displayed a lower blood pressure and hip circumference. A decrease in Akkermansia and Intestimonas as well as an increase in Bifidobacterium and Anaerostipes characterized BED subjects. Interestingly, metabolomics analysis revealed that BED subjects displayed a higher level of one food contaminants, Bisphenol A bis(2,3-dihydroxypropyl) ether (BADGE.2H(2)O) and a food derived-metabolite the Isovalerylcarnitine.ConclusionsNon-targeted omics approaches allow to select specific microbial genera and two plasma metabolites that characterize BED obese patients. Further studies are needed to confirm their potential role as drivers or biomarkers of binge eating disorder

Age at onset as stratifier in idiopathic Parkinson’s disease – effect of ageing and polygenic risk score on clinical phenotypes

Several phenotypic differences observed in Parkinson’s disease (PD) patients have been linked to age at onset (AAO). We endeavoured to find out whether these differences are due to the ageing process itself by using a combined dataset of idiopathic PD (n = 430) and healthy controls (HC; n = 556) excluding carriers of known PD-linked genetic mutations in both groups. We found several significant effects of AAO on motor and non-motor symptoms in PD, but when comparing the effects of age on these symptoms with HC (using age at assessment, AAA), only positive associations of AAA with burden of motor symptoms and cognitive impairment were significantly different between PD vs HC. Furthermore, we explored a potential effect of polygenic risk score (PRS) on clinical phenotype and identified a significant inverse correlation of AAO and PRS in PD. No significant association between PRS and severity of clinical symptoms was found. We conclude that the observed non-motor phenotypic differences in PD based on AAO are largely driven by the ageing process itself and not by a specific profile of neurodegeneration linked to AAO in the idiopathic PD patients

Critical transitions in chronic disease: Transferring concepts from ecology to systems medicine

Ecosystems and biological systems are known to be inherently complex and to exhibit nonlinear dynamics. Diseases such as microbiome dysregulation or depression can be seen as complex systems as well and were shown to exhibit patterns of nonlinearity in their response to perturbations. These nonlinearities can be revealed by a sudden shift in system states, for instance from health to disease. The identification and characterization of early warning signals which could predict upcoming critical transitions is of primordial interest as prevention of disease onset is a major aim in health care. In this review, we focus on recent evidence for critical transitions in diseases and discuss the potential of such studies for therapeutic applications

Eléments de bilan du programme quinquennal 1998-2003 et réflexions

Bilan établi sur base d'un travail préparatoire de la direction générale de la santé et des quatre services communautaires de promotion de la santé (ULG-APES, ULB-PROMES, UCL-RESO, Question santé asbl

Genome-wide network model capturing seed germination reveals coordinated regulation of plant cellular phase transitions

A multidisciplinary expert panel, appointed by the High Council for Public Health, evaluated the scientific evidence on which the recommendations for the appropriate use of the pneumococcal vaccine was based and reviewed the studies that became available since previous reports. The conclusions of the working group, presented in this manuscript, resulted in an update of the Belgian recommendations for pneumococcal vaccination.SCOPUS: sh.jinfo:eu-repo/semantics/publishe