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The aging western society is heavily afflicted with intervertebral disc (IVD) degeneration. Replacement or repair of the degenerated IVD with an artificial bio-mimetic construct is one of the challenges of future research due to its complex structure and unique biomechanical function. Herein, biocomposite laminates made of long collagen fibers in unidirectional (−1.3 ± 2.1°) and angle-plied ± 30° orientations (30.4 ± 6.4 and −29.8 ± 4.5), embedded in alginate hydrogel, were fabricated to mimic the form of single annulus fibrosus (AF) lamella and the circumferential AF, respectively. The mechanical behavior of the composites was measured and compared with in vitro existing data of the human native AF as well as with new data obtained from ovine and bovine specimens. The mechanical behavior was found to reproduce the full stress- strain behavior of the human AF single lamella in several regions of the AF and the Young's modulus was 28.3 ± 8.6 MPa. Moreover, the modulus of the angle-plied laminates was 16.8 ± 2.9 MPa, which is approximately 5% less than the in vitro data. The full stress-strain behavior was also compared with bovine and ovine circumferential AF samples and found to be very similar, with a difference in the modulus of 4.1% and 19.7%, respectively. Moreover, an FE model of the L3-L4 functional spinal unit (FSU) was developed and calibrated to evaluate the mechanical ability of the biocomposite to be used as an AF substitute under physiological IVD loading modes. The biocomposite demonstrated a good ability to mimic the stiffness of the native tissue under physiologic loading modes as flexion, extension, lateral bending and compression, but was too flexible under torsion. It was found that the proposed biomimetics AF design resulted in a compatible function in several mechanical levels, which holds great potential to be used as a viable AF replacement towards full IVD engineering. [ABSTRACT FROM AUTHOR]

Cascading crises and disasters in the global interconnected system are emerging topics in today's disaster risk reduction research. The primary objective is improving the capability of our societies to cope with such events and mitigate their detrimental consequences through an evolved understanding of their nature. Rather than being merely considered as an outcome of low-probability/high-impact processes, cascading events can be associated with the cross-scale accumulation of vulnerability paths constituted by events waiting to happen. In this context, instead of focusing solely on triggering events, it seems important to point out the interactions orienting the escalation of secondary emergencies through vulnerability paths. This special issue integrates those emerging aspects with an operational approach that considers cascades as the complex, non-linear escalation of secondary emergencies. Key topics addressed by the contributions include: cross-domain modelling of interdependent systems; decision support systems; economic impact assessment of critical events; and cascades in the built environment, in social domains, and in applied emergency management. Our conclusions support the work of academia, and of public and private stakeholders, by providing a comprehensive analysis of the topic for the improvement of theory, the assessment of resilience, the formulation of policies for managing crises, and operational planning for emergencies. [ABSTRACT FROM AUTHOR]

During the last decades, input-output (I/O) economic models have assumed a prominent role in disaster impact analysis and resilience assessment. Rooted in general equilibrium theory and economic production theory, they catalyse attention on the distinction between direct economic losses and ripple effects that may be generated inside a multi-industry system as a consequence of perturbations. Empowering the I/O analysis framework and overcoming some of its inherent limitations is crucial in order to successfully approach emerging disaster assessment challenges, such as multi-regional loss quantification and the investigation of shock responses in global supply chains. In this paper, we review and discuss how different disaster modeling aspects have been incorporated in recent contributions exploiting I/O techniques, taking into account both demand- and supply-sided perturbation triggers, static and dynamic representations, as well as the assessment of economic resilience. [ABSTRACT FROM AUTHOR]

This paper deals with switched linear systems subject to time-varying delay. The main goal is to design state and output feedback switching strategies preserving closed-loop stability and a guaranteed H 2 or H ∞ performance. The switching strategies are based on a generalization of a recent extended version of the small gain theorem and do not require any assumption on the continuity of the delay and its time-variation rate. The key point to obtain the design conditions is the adoption of an equivalent switched linear system where the time-varying delay is modeled as a norm-bounded perturbation. Moreover, with this approach, it is possible to deal with sampled-data control systems. All conditions are formulated in terms of Lyapunov–Metzler inequalities, which allow the maximization of an upper bound on the time-delay preserving stability and guaranteed performance. Numerical examples are discussed in order to illustrate the effectiveness of the design approach. [ABSTRACT FROM AUTHOR]

Several institutions worldwide are reflecting on the relevance of training and exercises to critical infrastructure protection and resilience. This is witnessed, for instance, by Council Directive 2008/114/EC in the EU and the Homeland Security Exercise and Evaluation Program in the US. Contributing to the research actions in the field, the present article discusses methodological approaches, tools, techniques, and technologies relevant to this domain. In particular, we report on a recent training initiative elaborated by the authors and involving a game-based, modelling-and-simulation-backed, computer-assisted exercise for critical infrastructure expert audiences. This was developed taking advantage of JRC's Geospatial Risk and Resilience Assessment Platform (GRRASP) and critical infrastructure analysis methodologies integrated therein. The overarching objective was to enhance system thinking and raise awareness of resilience aspects while familiarizing participants with specific analysis tools and scientific models. [ABSTRACT FROM AUTHOR]

Abstract: Policy makers and managers are increasingly called upon to assess the state of biodiversity, and make decisions regarding potential interventions. Genetic tools are well-recognised in the research community as a powerful approach to evaluate species and population status, reveal ecological and demographic processes, and inform nature conservation decisions. The wealth of genetic data and power of genetic methods are rapidly growing, but the consideration of genetic information and concerns in policy and management is limited by the currently low capacity of decision-makers to access and apply genetic resources. Here we describe a freely available, user-friendly online resource for decision-makers at local and national levels (http://congressgenetics.eu), which increases access to current knowledge, facilitates implementation of studies and interpretation of available data, and fosters collaboration between researchers and practitioners. This resource was created in partnership with conservation practitioners across the European Union, and includes a spectrum of taxa, ecosystems and conservation issues. Our goals here are to (1) introduce the rationale and context, (2) describe the specific tools (knowledge summaries, publications database, decision making tool, project planning tool, forum, community directory), and the challenges they help solve, and (3) summarise lessons learned. This article provides an outlook and model for similar efforts to build policy and management capacity. [Copyright &y& Elsevier]

Abstract: The objective of this study was to determine the viscoelastic properties of human meniscal tissue during stress-relaxation under confined compression conditions. Lateral and medial longitudinal meniscus plugs of 25 donor knees (n total=150) were exposed to stress-relaxation tests under confined compression conditions at three compression levels (ε=0.1; 0.15; 0.2). Mathematical modelling using an exponential 1D-diffusion equation was used to predict the viscoelastic properties. Subsequently, finite element (FE) models were created using identical geometry, properties and test conditions as used for the in-vitro tests. Two constitutively different underlying mathematical formulations were applied to the FE models to reveal possible differences in their predictions for the relaxation response. While the first FE model mimicked the analytical model (FE1), the second FE model used a different biphasic, non-linear approach (FE2). Regression analyses showed promising coefficients of determination (R 2>0.73) between the experimental data and the predictions obtained from the diffusion equation and the two FE models. Mean aggregate modulus, predicted with the diffusion equation (H A =64.0kPa) was lower than those obtained with the two FE analyses (H A,FE1=91.9kPa; H A,FE2=81.5kPa). Mean hydraulic permeability (k FE2=1.5×10−15 m4/Ns) of the second FE2 approach was statistically lower (p<0.01) than the other permeability values (k=3.9×10−15 m4/Ns; k FE1=3.4×10−15 m4/Ns). These differences are mainly due to the different underlying mathematical models used. However, when compared with corresponding literature, the results of the present study indicated good agreement. The results of the present study contribute to a better understanding of the complex nature of meniscal tissue and might also have an impact on the design of future meniscal substitutes. [Copyright &y& Elsevier]

Abstract: Osmotic phenomena influence the intervertebral disc biomechanics. Their simulation is challenging and can be undertaken at different levels of complexity. Four distinct approaches to simulate the osmotic behaviour of the intervertebral disc (a fixed boundary pore pressure model, a fixed osmotic pressure gradient model in the whole disc or only in the nucleus pulposus, and a swelling model with strain-dependent osmotic pressure) were analysed. Predictions were compared using a 3D poroelastic finite element model of a L4–L5 spinal unit under three different loading conditions: free swelling for 8 h and two daily loading cycles: (i) 200 N compression for 8 h followed by 500 N compression for 16 h; (ii) 500 N for 8 h followed by 1000 N for 16 h. Overall, all swelling models calculated comparable results, with differences decreasing under greater loads. Results predicted with the fixed boundary pore pressure and the fixed osmotic pressure in the whole disc models were nearly identical. The boundary pore pressure model, however, cannot simulate differential osmotic pressures in disc regions. The swelling model offered the best potential to provide more accurate results, conditional upon availability of reliable values for the required coefficients and material properties. Possible fields of application include mechanobiology investigations and crack opening and propagation. However, the other approaches are a good compromise between the ease of implementation and the reliability of results, especially when considering higher loads or when the focus is on global results such as spinal kinematics. [Copyright &y& Elsevier]

Mitochondria are key organelles for cellular energetics, metabolism, signaling, and quality control and have been linked to various diseases. Different views exist on the composition of the human mitochondrial proteome. We classified >8,000 proteins in mitochondrial preparations of human cells and defined a mitochondrial high-confidence proteome of >1,100 proteins (MitoCoP). We identified interactors of translocases, respiratory chain, and ATP synthase assembly factors. The abundance of MitoCoP proteins covers six orders of magnitude and amounts to 7% of the cellular proteome with the chaperones HSP60-HSP10 being the most abundant mitochondrial proteins. MitoCoP dynamics spans three orders of magnitudes, with half-lives from hours to months, and suggests a rapid regulation of biosynthesis and assembly processes. 460 MitoCoP genes are linked to human diseases with a strong prevalence for the central nervous system and metabolism. MitoCoP will provide a high-confidence resource for placing dynamics, functions, and dysfunctions of mitochondria into the cellular context. [Display omitted] • Human mitochondrial high-confidence proteome with >1,100 proteins (MitoCoP) • Mitochondria-specific protein copy numbers and half-lives • Interactors of protein translocases and oxidative phosphorylation assembly factors • >40% of mitochondrial proteome linked to human diseases Mitochondria are crucial for cellular energy metabolism and human health. Morgenstern et al. present a high-confidence protein compendium of human mitochondria including mitochondria-specific protein copy numbers and half-lives. They identify interactors of key mitochondrial protein machineries and link >40% of the mitochondrial proteome to human diseases. [ABSTRACT FROM AUTHOR]

Proper statistical analysis is essential in the research studies. In particular, as regards the in vitro testing of the lumbar spine, the criteria for the standardization have been extensively discussed but the use of statistics has not been reviewed. Unfortunately, cadaveric testing is a very difficult and complex experimental field, in which many factors such as collection times, costs, funding, personnel and logistic issues, availability of implant components, can determinate low sample sizes, with impacts on the statistical evaluation. Moreover, as in any other field, some errors can be commonly made in the choice of the most appropriate statistical tests. The present tutorial article provides a comprehensive overview of the theoretical basics of the statistical approach, focusing on the experimental testing of the lumbar spine. Reference values about adequate sample size and statistical power were provided. The use of statistics was reviewed in a selection of 20 papers, chosen among the most cited and representative contributions for the in vitro study of the lumbar spine. Overall, only 7 in 20 papers applied fully corrected procedures. The achieved power, calculated for the medium conventional level of the effect size, ranged from 0.13 to 0.99 but overall was found rather poor, below 0.6. The study also revealed that applying incorrect statistical tests and having low sample size can impact p-value and power, respectively, with consequences on the identification of the significant outcomes. We emphasize that this review is not intended as a mere critical analysis from a statistical perspective, but as a constructive investigation aimed to support the researchers in the challenging field of cadaveric testing. It is worth noting that the provided recommendations and reference values can be also accounted for experimental scenarios testing the other spine regions, either in human or in animal models. Image 1 • Tutorial article on the use of statistics in experimental study of the human spine. • Overview of theoretical basics and application to the lumbar spine are provided. • Reference sample size values and computation using G*Power free tool are reported. • The use of statistics was reviewed in a selection of 20 representative papers. • Indications and reference values are applicable to other spine regions, human/animal. [ABSTRACT FROM AUTHOR]