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Aim: The purpose of this umbrella review is to bring together the most recent reviews concerning the relationship between gut-microbiota and sport activity. Materials and Methods: A literature search was conducted through PubMed and focused on reviews and systematic reviews published between 2015 and June 2021 that dealt with the topic of microbiota and physical activity. Only articles written in English and published in peer-reviewed journals were considered. Key words related to the term microbiota alone or in conjunction with other terms such as "supplements", "diet", "probiotics", "prebiotics", "health", "physical activity", and "pathogens" were analyzed. The selection process was done first by analyzing the titles, then the abstracts, and finally the full text. Results: After screening the title and abstract, 29 articles were excluded. Therefore, 20 studies were included in the present umbrella review. The figure shows the steps of the selection process (Figure 1). The specifications of the presented articles are listed in Table 2. Conclusions: Exercise appears to be an environmental factor that can determine changes in the gut microbial composition with possible benefits for the host. Increased microbiota diversity improves metabolic profile and immunological responses and may provide a possible biomarker for health improvement. Exercise altered microbiota could be used to look for new approaches in the treatment of metabolic and inflammatory diseases.

Alginates are products used as impression materials in dentistry and prosthetics. They consist of polymers, calcium alginates mixed with diatomite and additives. Recently, the occurrence of severe silicosis associated with exposure to respirable dust of such materials has increased the scientific interest in understanding how these materials may pose a toxicological problem to workers. The primary objective of this study is to improve the understanding of both the existence and the characteristics of the toxicant(s) contained in these materials, with the goal of better defining the risk assessment for this occupational setting.Two commercial dental alginates were subjected to a mineralogical, microchemical and spectroscopic investigation. The results indicate the presence of a significant amount of diatomite, clearly identified by micromorphology and formed mainly by cristobalite. The respirable fraction of the dust represents at least 30 % of the total number of particles, and this fraction contains a relevant amount of crystalline silica particles. Conversely, the investigated alginate materials do not exhibit the presence of radical species.The results obtained confirm that the cristobalite detected originates from the high-temperature transformation of amorphous silica during the calcination process of diatomite, prior to mixing with the other components. The same process also produces wollastonite (CaSiO3), which, like cristobalite, is a crystalline phase known for its toxicological effects. The present findings call for a rethinking of dental alginates with regard to the definition of their health risks for technical operators.

The human gastrointestinal tract hosts a complex and dynamic population of commensal bacterial species, which have coevolved with the host, generating a symbiotic relationship. Some compounds present in foods, such as polyols, prebiotic fibers, or phenolic compounds, are poorly metabolized and absorbed by the host before the transformation guided by the colonic microbiota. By influencing gut microbiota, diet plays a fundamental role in understanding the beneficial effects of the gut microbiota on the host, including its long-term metabolism. The idea that probiotics can act not only by influencing the colonizing microbiota opens the door to a wider range of probiotic possibilities, encouraging innovation in the field. Furthermore, it has been shown both that some probiotics increase phagocytosis or the activity of natural killer cells. Current prebiotics are mainly based on carbohydrates, but other substances, such as polyphenols and polyunsaturated fatty acids, could exert prebiotic effects. A prebiotic substance has been defined as ‘a substrate that is selectively used by host microorganisms that confer a health benefit’, and so can interact with the gut microbiota through competition for nutrients, antagonism, cross-feeding, and support for microbiota stability. Influencing its composition in terms of richness and diversity, food components have a key impact on the intestinal microbiota. Eating habits can strongly influence the composition of the intestinal microbiota. A healthy intestinal microbiota is essential for maintaining general health, and diet is one of the major modulators of this fascinating world of microorganisms. This must give us one more reason to adopt a healthy lifestyle.

Risk assessment and mitigation programs have been carried out over the last decades in the attempt to reduce transportation infrastructure downtime and post-disaster recovery costs. Recently, the concept of resilience gained increasing importance in design, assessment, maintenance, and rehabilitation structures and infrastructure systems, particularly bridges and transportation networks, exposed to natural and man-made hazards. In the field of disaster mitigation, frameworks have been proposed to provide a basis for development of qualitative and quantitative models quantifying the functionality and resilience at various scales, including components, groups and systems within infrastructure networks and communities. In these frameworks, the effects of aging and environmental aggressiveness must be explicitly considered, affecting the structural performance and functionality of civil infrastructure systems. Significant efforts have been made to incorporate risk and resilience assessment frameworks into informed decision making to decide how to best use resources to minimize the impact of hazards on civil infrastructure systems. This review paper is part of these efforts. It presents an overview of the main principles and concepts, methods and strategies, advances and accomplishments in the field of life-cycle reliability, risk and resilience of structures and infrastructure systems, with emphasis on seismic resilience of bridges and road networks.

The relationship between microbiota and chronic kidney disease (CKD) has long been known [...]

This paper proposes a mathematical framework for optimal retrofit and recovery strategies of bridge networks. The pre-earthquake and postearthquake management of the highway systems is addressed considering performance objectives based on seismic resilience and life-cycle costs. Structural capacity of vulnerable bridges and traffic performance of the transportation network are investigated accounting for the effects of aftershocks by state-dependent fragility curves informing cumulative damage scenarios. Optimal intervention sequences are identified under uncertainties related to bridge damage levels and mainshock–aftershock sequences based on a biobjective optimization problem aiming to maximize network resilience and minimize costs associated with pre-event retrofit and postrepair restoration activities. [ABSTRACT FROM AUTHOR]