Emergence of Diversity in a Group of Identical Bio-Robots

Learning capabilities, often guided by competition/cooperation, play a fundamental and ubiquitous role in living beings. Moreover, several behaviours, such as feeding and courtship, involve environmental exploration and exploitation, including local competition, and lead to a global benefit for the colony. This can be considered as a form of global cooperation, even if the individual agent is not aware of the overall effect. This paper aims to demonstrate that identical biorobots, endowed with simple neural controllers, can evolve diversified behaviours and roles when competing for the same resources in the same arena. These behaviours also produce a benefit in terms of time and energy spent by the whole group. The robots are tasked with a classical foraging task structured through the cyclic activation of resources. The result is that each individual robot, while competing to reach the maximum number of available targets, tends to prefer a specific sequence of subtasks. This indirectly leads to the global result of task partitioning, whereby the cumulative energy spent, in terms of the overall travelled distance and the time needed to complete the task, tends to be minimized. A series of simulation experiments is conducted using different numbers of robots and scenarios: the common emergent result obtained is the role specialization of each robot. The description of the neural controller and the specialization mechanisms are reported in detail and discussed

16S metagenomics reveals dysbiosis of nasal core microbiota in children with chronic nasal inflammation: role of adenoid hypertrophy and allergic rhinitis

Allergic rhinitis (AR) and adenoid hypertrophy (AH) are, in children, the main cause of partial or complete upper airway obstruction and reduction in airflow. However, limited data exist about the impact of the increased resistance to airflow, on the nasal microbial composition of children with AR end AH. Allergic rhinitis (AR) as well as adenoid hypertrophy (AH), represent extremely common pathologies in this population. Their known inflammatory obstruction is amplified when both pathologies coexist. In our study, the microbiota of anterior nares of 75 pediatric subjects with AR, AH or both conditions, was explored by 16S rRNA-based metagenomic approach. Our data show for the first time, that in children, the inflammatory state is associated to similar changes in the microbiota composition of AR and AH subjects respect to the healthy condition. Together with such alterations, we observed a reduced variability in the between-subject biodiversity on the other hand, these same alterations resulted amplified by the nasal obstruction that could constitute a secondary risk factor for dysbiosis. Significant differences in the relative abundance of specific microbial groups were found between diseased phenotypes and the controls. Most of these taxa belonged to a stable and quantitatively dominating component of the nasal microbiota and showed marked potentials in discriminating the controls from diseased subjects. A pauperization of the nasal microbial network was observed in diseased status in respect to the number of involved taxa and connectivity. Finally, while stable co-occurrence relationships were observed within both control- and diseases-associated microbial groups, only negative correlations were present between them, suggesting that microbial subgroups potentially act as maintainer of the eubiosis state in the nasal ecosystem. In the nasal ecosysteminflammation-associated shifts seem to impact the more intimate component of the microbiota rather than representing the mere loss of microbial diversity. The discriminatory potential showed by differentially abundant taxa provide a starting point for future research with the potential to improve patient outcomes. Overall, our results underline the association of AH and AR with the impairment of the microbial interplay leading to unbalanced ecosystems

Integrative Biomimetics of Autonomous Hexapedal Locomotion

Dürr V, Arena PP, Cruse H, et al. Integrative Biomimetics of Autonomous Hexapedal Locomotion. Frontiers in Neurorobotics. 2019;13: 88.Despite substantial advances in many different fields of neurorobotics in general, and biomimetic robots in particular, a key challenge is the integration of concepts: to collate and combine research on disparate and conceptually disjunct research areas in the neurosciences and engineering sciences. We claim that the development of suitable robotic integration platforms is of particular relevance to make such integration of concepts work in practice. Here, we provide an example for a hexapod robotic integration platform for autonomous locomotion. In a sequence of six focus sections dealing with aspects of intelligent, embodied motor control in insects and multipedal robots—ranging from compliant actuation, distributed proprioception and control of multiple legs, the formation of internal representations to the use of an internal body model—we introduce the walking robot HECTOR as a research platform for integrative biomimetics of hexapedal locomotion. Owing to its 18 highly sensorized, compliant actuators, light-weight exoskeleton, distributed and expandable hardware architecture, and an appropriate dynamic simulation framework, HECTOR offers many opportunities to integrate research effort across biomimetics research on actuation, sensory-motor feedback, inter-leg coordination, and cognitive abilities such as motion planning and learning of its own body size

Characterization of particle emission from laser printers

Emission of particles from laser printers in office environments is claimed to have impact on human health due to likelihood of exposure to high particle concentrations in such indoor environments. In the present paper, particle emission characteristics of 110 laser printers from different manufacturers were analyzed, and estimations of their emission rates were made on the basis of measurements of total concentrations of particles emitted by the printers placed in a chamber, as well as particle size distributions. The emission rates in terms of number, surface area and mass were found to be within the ranges from 3.39 × 108 part min− 1to 1.61 × 1012 part min− 1, 1.06 × 100 mm2 min− 1to 1.46 × 103 mm2 min− 1and 1.32 × 10− 1 μg min− 1to 1.23 × 102 μg min− 1, respectively, while the median mode value of the emitted particles was found equal to 34 nm. In addition, the effect of laser printing emissions in terms of employees' exposure in offices was evaluated on the basis of the emission rates, by calculating the daily surface area doses (as sum of alveolar and tracheobronchial deposition fraction) received assuming a typical printing scenario. In such typical printing conditions, a relatively low total surface area dose (2.7 mm2) was estimated for office employees with respect to other indoor microenvironments including both workplaces and homes. Nonetheless, for severe exposure conditions, characterized by operating parameters falling beyond the typical values (i.e. smaller office, lower ventilation, printer located on the desk, closer to the person, higher printing frequency etc.), significantly higher doses are expected

Occurrence of Pseudomonas aeruginosa in several sources of drinking water

Introduction Pseudomonas aeruginosa is an environmental ubiquitous bacterium that may cause opportunistic waterborne infections in immunocompromised host. It can be isolated in several aquatic habitat where it shows the ability to survive in a quiescent metabolic state under stressful conditions and to revert to a metabolically active status when environmental conditions allow. In domestic environment it is not rare to find it associated with the water piping system, producing a thick layer of biofilm. Many strains that are biofilm producers express virulence factors and resistances to several antibiotic classes. This study aims to isolate and characterize P. aeruginosa and other Gram-negative bacteria in a range of types of drinking water. Materials and Methods For each water source, 1 liter sample was aseptically collected in sterile flasks containing sodium thiosulfate to neutralize chlorine. The samples were kept at +4 °C and analyzed within 24 hours. Isolation and enumeration of P. aeruginosa was carried out by membrane filtration technique according to the UNI EN ISO 16266: 2008. The isolated strains were identified and tested for antibiotic resistance by Vitek 2 (Biomérieux). All Pseudomonas isolates were tested for biofilm production by violet crystal staining in multiwell 96 plates and their growth was compared to those of strongly producing biofilm reference strains. All strains were stored at -80 ° C for further studies. Results A total of one hundred water samples from different sources was analyzed: tap water, domestic deionizer water (from home filtration devices), water dispensers, ground water and mineral water springs. In most of the samples directly from the drinking water system a microbial load < 10 CFU/L has been detected. In 1/3 of the samples till now analyzed, Gram-negative species, resistant to the chlorine, have been identified. A higher percentage of samples from domestic deionizer and dispenser waters resulted positive for the presence of P. aeruginosa than ground and tap water samples. Discussion and Conclusions Our preliminary data highlight a critical issue related to the home filtration devices installed in the terminal part of taps. Although the water suppliers constantly check the ensuring compliance with the microbial load parameters, the last part of the private pipes frequently hosts microorganisms organized in biofilms mono or multi species able to alter the microbiological quality of water. Deionized water samples have been resulted a large reservoir of microbial diversity. Indeed, the great filtering surface provides perfect substrate to sessile forms triggering the biofilm production and enhancing the growth of bacteria routinely living in drinking water. Further sampling and analysis are necessary to drive reliable conclusions

Antimicrobial activity of the essential oil from Satureya montana, L. Lamiaceae

Many plants derived essential oils (EOs) exert antibacterial activity and have been screened as potential sources of novel antimicrobial compounds. EOs and their components are hydrophobic molecules, which allows to partition with the lipids of the bacterial cell membrane, interfering with the bacterial cell permeability. EOs of the plant genus Satureja are known to have biological properties such as antimicrobial, fungicidal, anti-HIV-1 and anticholinesterase ability; other studies suggest antibiofilm and anti-adhesive properties

Effect of Satureja montana L. (Lamiaceae) essential oil based nanoemulsions against avian Escherichia coli strains

Massive use of antibiotics in breeding farm has contributed to the spread of multidrug resistant bacteria and poultry has been suggested as a reservoir for multidrug -resistant Escherichia coli strains. Many plant derived essential oils (EOs) exhibit biological activitymainly due to typical features of their components such as hydrophobicity, that allows partitioning with the lipids of the bacterial cell membrane interfering with the cell permeability and resulting in a bactericidal/bacteriostatic effect. Nanoemulsions (NEs) are colloidal dispersion in which main components are oil, emulsifying agents and aqueous phases. NEs were investigated to improving the delivery of active pharmaceutical or natural ingredients. In order to test the inhibiting activity on bacterial growth and biofilm production, NEs obtained from S. Montana essential oil has been tested against E. coli isolates from healthy poultry fecal samples characterized for antibiotic resistance and metal tolerance

Escherichia coli strains of chicken and human origin. Characterization of antibiotic and heavy-metal resistance profiles, phylogenetic grouping, and presence of virulence genetic markers

Multiple antibiotic-resistant extra-intestinal pathogenic Escherichia coli (ExPEC) strains represent a serious health care problem both for poultry and humans. Recently isolates with combined resistance to both antibiotics and heavy metals have been increased worldwide, with growing concern for possible co-selection of antimicrobial resistant genes. In the present study we characterized, at a phenotypic and genetic level, 80 E. coli isolates: forty independent isolates were collected from manure samples of healthy chickens and 40 from independent human extra-intestinal infections (ExPEC strains). The results obtained indicated that i) compared to chicken, human isolates presented a broader spectrum of antibiotic resistance and virulence potentials; ii) although at a lower extent, ExPEC-associated virulence genes were also present in chicken isolates, suggesting they may be potentially pathogens; iii) that arsenic (As) and zinc (Zn) tolerance genetic determinants were significantly more prevalent among chicken and human isolates respectively, while those responsible for tolerance to cadmium (Cd), silver (Ag) and copper (Cu) were equally distributed among the two groups of strains; iv) a very strong correlation was found between chicken gentamicin (GM) resistance and cadmium (Cd) tolerance. Elucidating the role of heavy metals in the selection and spread of highly pathogenic E. coli strains (co-selection) is of primary importance to lower the potential risk of infections in poultry and humans. The control of bacterial zoonotic agents, that commonly occur in livestock and that may be transmitted, directly or via the food chain, to human populations, could be of relevant interest

Satureja montana L. essential oil and its antimicrobial activity alone or in combination with gentamicin

Many essential oils (EOs) are screened as potential sources of antimicrobial compounds. EOs from the genus Satureja have recognized biological properties, including analgesic, anti-inflammatory, immunomodulatory, anti-cancer, and antimicrobial activity. This study aimed to obtain a metabolite profile of commercial essential oil of S. montana L. (SEO) and to evaluate its antimicrobial properties, both alone and combined with gentamicin towards Gram-negative and Gram-positive bacterial strains. Untargeted analyses based on direct infusion Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and on GC-MS have provided a high metabolome coverage, allowing to identify carvacrol, cymene and thymol as the major components of commercial SEO. SEO exerted an antimicrobial activity and induced a synergistic interaction with gentamicin against both reference and clinical bacterial strains. A significant reduction of Escherichia coli, Staphylococcus aureus and Listeria monocytogenes biofilm formation was induced by SEO. As a result of SEO treatment, clear morphological bacterial alterations were visualized by scanning electron microscopy: L. monocytogenes and S. aureus showed malformed cell surface or broken cells with pores formation, whereas E. coli displayed collapsed cell surface. These results encourage further studies about bactericidal and antibiotic synergistic effect of SEO for combined therapy in clinical setting as well as in agricultural systems