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When it comes to computing the values of variables defining the preliminary sizing of an airship, a few standardized approaches are available in the existing literature. However, when including a disruptive technology in the design is required, sizing procedures need to be amended, so as to be able to deal with the features of any additional novel item. This is the case of atmospheric ionic thrusters, a promising propulsive technology based on electric power, where thrusters feature no moving parts and are relatively cheap to manufacture. The present contribution proposes modifications to an existing airship design technique, originally conceived accounting for standard electro-mechanical thrusters, so as to cope with the specific features of new atmospheric ionic thrusters. After introducing this design procedure in detail, its potential is tested by showing results from feasibility studies on an example airship intended for a high-altitude mission. Concurrently, the so-obtained results allow the demonstration of the sizing features corresponding to the adoption of atmospheric ionic thrusters at the current level of technology, comparing them to what is obtained for the same mission when employing a standard electro-mechanical propulsion system.

The cell is the basic unit of life. It is composed of organelles and various organic and inorganic biomolecules. Recent 16S ribosomal ribonucleic acid (16S rRNA) gene sequencing studies have revealed the presence of tissue bacteria in both tumor and normal tissues. Recently, we found that the liver microbiome resided in hepatocytes. Here, we further report on the cellular microbiome in the parenchymal cells of visceral organs as inherent inhabitants. We performed 16S rRNA gene sequencing on visceral organs of male adult Sprague Dawley (SD) rats, pregnant rats, newborn rats, and fetuses and placentas; then, we performed fluorescence in situ hybridization and immunofluorescence in visceral organs. Furthermore, we performed Western blotting on nuclear and cytoplasmic extractions of visceral organs of SD rats and cell lines HepG2, Huh-7, Hepa1-6, and HSC-T6. A high abundance of 16S rRNA gene was detected in the visceral organs of male adult, pregnant, newborn, and fetal rats as well as their placentas. The number of operational taxonomic units (OTUs) of visceral bacteria was higher than that of the feces and ileum bacteria. Bacterial 16S rRNA, lipopolysaccharide (LPS), and lipoteichoic acid (LTA) were found in the parenchymal cells of visceral organs, as well as in HepG2, Huh-7, HSC-T6, and Hepa1-6 cells. LPS consistently appeared in the nucleus of cells, while LTA was mainly found in the cytoplasm. In conclusion, the cellular microbiome is an intrinsic component of cells. Gram-negative bacteria are located in the nucleus, and Gram-positive bacteria are located in the cytoplasm. This differs from the gut microbiome and may be inherited.

Macrophage polarization to the M1 spectrum is induced by bacterial cell wall components through stimulation of Toll-like family (TLR) receptors. By orchestrating the expression of relevant mediators of the TLR cascade, as well as associated pathways and feedback loops, macrophage polarization is coordinated to ensure an appropriate immune response. This is central to the successful control of pathogens and the maintenance of health. Macrophage polarization is known to be modulated at both the transcriptional and post-transcriptional levels. In recent years, the miRNA-based post-transcriptional regulation of M1 polarization has received increasing attention from the scientific community. Comparative studies have shown that TLR stimulation alters the miRNA profile of macrophages and that macrophages from the M1 or the M2 spectrum differ in terms of miRNAs expressed. Simultaneously, miRNAs are considered critical post-transcriptional regulators of macrophage polarization. In particular, miRNAs are thought to play a regulatory role in the switch between the early proinflammatory response and the resolution phase. In this review, we will discuss the current state of knowledge on the complex interaction of transcriptional and post-transcriptional regulatory mechanisms that ultimately determine the functionality of macrophages.

Life expectancy has increased globally in recent decades, driving interest in maintaining a healthy life that includes preservation of physical and mental abilities, particularly in elderly people. The gut microbiome becomes increasingly perturbed with aging so the use of probiotics can be a strategy for maintaining a balanced gut microbiome. A previous report showed that Bifidobacterium animalis subsp. lactis BPL1™ induces through its lipoteichoic acid (LTA) fat reduction activities via the insulin/IGF-1 signaling pathway. Here, we have delved into the mechanism of action, eliminating alternative pathways as putative mechanisms. Furthermore, we have identified that BPL1™, its heat treated form (BPL1™ HT) and its LTA prolong longevity in Caenorhabditis elegans (C. elegans) in an insulin/IGF-1-dependent mechanism, and its consumption improves the oxidative stress response, gut permeability and protection against pathogenic infections. Furthermore, positive effects on C. elegans stress-related behaviors and in the Alzheimer’s Disease model were found, highlighting the potential of the strain in improving the cognitive functions and proteotoxicity in the nematode. These results indicate the pivotal role of the IGF-1 pathway in the activity of the strain and pave the way for potential applications of BPL1™, BPL1™ HT and its LTA in the field of longevity and age-related markers.

The use of wastes is necessary to contribute to environmental sustainability. In this study, ore mining tailings were used as the raw material and precursor for the synthesis of LTA zeolite, a value-added product. Pre-treated mining tailings were submitted to the synthesis stages under specific established operational conditions. The physicochemical characterization of the synthesized products was performed with XRF, XRD, FTIR and SEM, to identify the most cost-effective synthesis condition. The LTA zeolite quantification and its crystallinity were determined as effects of the SiO2/Al2O3, Na2O/SiO2 and H2O/Na2O molar ratios used, as well as the influence of the synthesis conditions: mining tailing calcination temperature, homogenization, aging and hydrothermal treatment times. The zeolites obtained from the mining tailings were characterized by the LTA zeolite phase accompanied by sodalite. The calcination of mining tailings favored the production of LTA zeolite, and the influence of the molar ratios, aging and hydrothermal treatment times were determined. Highly crystalline LTA zeolite was obtained in the synthesized product at optimized conditions. Higher methylene blue adsorption capacity was associated with the highest crystallinity of synthesized LTA zeolite. The synthesized products were characterized by a well-defined cubic morphology of LTA zeolite and lepispheres of sodalite. The incorporation of lithium hydroxide nanoparticles over LTA zeolite synthesized (ZA-Li+) from mining tailings yielded a material with improved features. The adsorption capacity towards cationic dye was higher than for anionic dye, especially for methylene blue. The potential of using ZA-Li+ in environmental applications related to methylene blue deserves detailed study.

In the current work an experimental method is used in order to calculate the diffusivity D (diffusion coefficient) of various vapors in thin zeolite films. The method is based on adsorption data from magnetoelastic sensors on top of which a zeolite layer was synthesized, and the diffusivity is extracted by fitting the data to Fick’s laws of diffusion. In particular, the method is demonstrated for two volatile organic compound (VOC) vapors on two different zeolites, the p-Xylene adsorption in Faujasite type zeolite with D = 1.89 × 10 − 13 m 2 / s at 120 ° C and the propene adsorption in Linde Type A type zeolite with D = 5.9 × 10 − 14 m 2 / s at 80 ° C , two diffusion coefficients which are extracted experimentally for first time. Our results are within the order of magnitude of other VOC/zeolite values reported in literature.

Time-stability of LTA zeolite formed by hydrothermal method with or without the action of ultrasonic irradiation was investigated by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The results show that 6 months after the synthesis by hydrothermal process with continuous sonication, LTA evolves into a more stable sodalite, whereas no differences are detected 12 months after LTA synthesis by conventional pre-fused hydrothermal process. These data confirm that using the two approaches, different mechanisms control both zeolite crystallization and time-stability of the newly-formed mineral at solid state. The results are particularly important in the light of the synthetic zeolite application.

Antimicrobial peptides (AMPS) are ancestral components in the evolution of immunity from protozoans to metazoans. Their expression can be constitutive or inducible by infectious challenge. Although characterized in detail in their structure and activity, the temporal and spatial expression of AMPS during vertebrate embryogenesis is still poorly understood. In the present study, we identified selected AMPs in zebrafish, and characterized their expression during early development, and upon experimental immune challenge in adult animals, with the goal of establishing this genetically-tractable model system for further AMP studies. By mining available genomic databases, zebrafish AMP sequences homologous to AMPs from other vertebrates were selected for further study. These included parasin I and its enzyme cathepsin D, β-defensin (DB1), liver-expressed antimicrobial peptide 2 (LEAP2), bactericidal permeability-increasing protein (BPI), and chromogranin-A and -B (CgA and CgB). Specific primers were designed for RT-PCR amplification of each AMP gene of interest and amplicons between 242 bp and 504 bp were obtained from RNA extracted from adult zebrafish. Sequencing of the amplicons and alignment of their deduced amino acid sequences with those from AMPs from other vertebrate species confirmed their identity. The temporal expression of AMPs was investigated by RT-PCR analysis in fertilized oocytes, embryos, and adult individuals. Parasin I and chatepsin D transcripts were detectable immediately after fertilization, while the transcripts for CgA and CgB became evident starting at 48 h post fertilization. Mature transcripts of LEAP2 and DB1 were detectable only in the adult zebrafish, while BPI transcripts were detectable starting from the 12th day post fertilization. To explore the possible upregulation of AMP expression by infectious challenge, experiments were carried out in adult zebrafish by intraperitoneal injection of a cocktail of lipopolysaccharide and lipoteichoic acid. Except for CgA and CgB, amplicons corresponding to all tested AMPs showed stronger signals in the experimental animals as compared to the unchallenged controls. This study provided information on the early expression of AMPs in zebrafish from ontogeny to adulthood and their inducibility by microbials. This information could be useful to actuate new prophylactic strategies as an alternative to the use of antibiotics in culture.

In this work, mixed matrix membranes (MMMs) composed of small-pore zeolites with various topologies (CHA (Si/Al = 5), LTA (Si/Al = 1 and 5), and Rho (Si/Al = 5)) as dispersed phase, and the hugely permeable poly(1-trimethylsilyl-1-propyne) (PTMSP) as continuous phase, have been synthesized via solution casting, in order to obtain membranes that could be attractive for oxygen-enriched air production. The O2/N2 gas separation performance of the MMMs has been analyzed in terms of permeability, diffusivity, and solubility in the temperature range of 298–333 K. The higher the temperature of the oxygen-enriched stream, the lower the energy required for the combustion process. The effect of temperature on the gas permeability, diffusivity, and solubility of these MMMs is described in terms of the Arrhenius and Van’t Hoff relationships with acceptable accuracy. Moreover, the O2/N2 permselectivity of the MMMs increases with temperature, the O2/N2 selectivities being considerably higher than those of the pure PTMSP. In consequence, most of the MMMs prepared in this work exceeded the Robeson’s upper bound for the O2/N2 gas pair in the temperature range under study, with not much decrease in the O2 permeabilities, reaching O2/N2 selectivities of up to 8.43 and O2 permeabilities up to 4,800 Barrer at 333 K.