Definition of a resistojet control system for the Manned Orbital Research Laboratory. Volume 3 - Biowaste utilization Final report

Biowaste utilization analysis for defining resistojet control system for Manned Orbital Research Laborator

Identification of aroma compounds of Vitis vinifera L. flowers by SPME GC-MS analysis

Using a gas chromatographic method (GC-MSanalysis), it was possible to determine the volatile constituent of an odorous flower from Vitis vinifera varieties growing in Sicily. More than 50 compounds were identified and the technique allowed us to determine that sesquiterpenes, as well as monoterpenes such as limonene and cymene, were the principal components. The odour-profiles allowed us to distinguish between variety groups or even single varieties.

Light-Dependent Electrogenic Activity of Cyanobacteria

Cyanobacteria account for 20-30% of Earth's primary photosynthetic productivity and convert solar energy into biomass-stored chemical energy at the rate of approximately 450 TW [1]. These single-cell microorganisms are resilient predecessors of all higher oxygenic phototrophs and can be found in self-sustaining, nitrogen-fixing communities the world over, from Antarctic glaciers to the Sahara desert [2].Here we show that diverse genera of cyanobacteria including biofilm-forming and pelagic strains have a conserved light-dependent electrogenic activity, i.e. the ability to transfer electrons to their surroundings in response to illumination. Naturally-growing biofilm-forming photosynthetic consortia also displayed light-dependent electrogenic activity, demonstrating that this phenomenon is not limited to individual cultures. Treatment with site-specific inhibitors revealed the electrons originate at the photosynthetic electron transfer chain (P-ETC). Moreover, electrogenic activity was observed upon illumination only with blue or red but not green light confirming that P-ETC is the source of electrons. The yield of electrons harvested by extracellular electron acceptor to photons available for photosynthesis ranged from 0.05% to 0.3%, although the efficiency of electron harvesting likely varies depending on terminal electron acceptor.The current study illustrates that cyanobacterial electrogenic activity is an important microbiological conduit of solar energy into the biosphere. The mechanism responsible for electrogenic activity in cyanobacteria appears to be fundamentally different from the one exploited in previously discovered electrogenic bacteria, such as Geobacter, where electrons are derived from oxidation of organic compounds and transported via a respiratory electron transfer chain (R-ETC) [3], [4]. The electrogenic pathway of cyanobacteria might be exploited to develop light-sensitive devices or future technologies that convert solar energy into limited amounts of electricity in a self-sustainable, CO(2)-free manner

Streptomyces coelicolor: DNA methylation and differentiation

DNA cytosine methylation is an epigenetic modification regulating many biological processes in eukaryotes, including chromatin organization, genome maintenance and gene expression. The role of DNA cytosine methylation in prokaryotes has not been deeply investigated. In Escherichia coli it was recently demonstrated that cytosine methylation regulates gene expression during stationary phase [1] and that an induced state of cytosine hypermethylation leads to chromosomal DNA cleavage and cell death [2]. Streptomyces coelicolor is a mycelial soil microorganism, which exhibits a complex life cycle that includes three different cell types: unigenomic spores, a compartmentalized mycelium (MI) and a multinucleated mycelium (substrate and aerial mycelium, MII) [3]. The importance of DNA methylation was already described in Streptomycetes [4], but its biological role remains unknown. The main objectives of this study are to analyze cytosine methylation pattern of Streptomyces coelicolor M145 during growth in liquid and on solid media, and to investigate the relationship between DNA cytosine methylation and morphological/physiological differentiation. Cytosine methylation of total genomic DNA extracted from different developmental stages was investigated by dot-blot experiments using antibody anti-5-methylcytosine. Cytosine methylome was analyzed by BiSulphite sequencing. The biological effect of cytosine methylation was studied adding 5-aza-2\u2019-deoxycytidine (aza-dC), a hypomethylating agent, to the cultures. Dot blot analysis revealed that the level of cytosine methylation changes during development (MI, MII and spores). Specifically, DNA methylation is higher at the MI stage than in the MII or spores. BiSulphite sequencing revealed that 30% of S. coelicolor genes contained a methylated motif in their upstream regions. Genes harbouring these motifs included genes related to differentiation (aerial mycelium formation and sporulation), genes involved in DNA repair/replication/condensation, as well as genes encoding proteins with unknown functions. Phenotypic analyses of cultures treated with aza-dC demonstrated that DNA methylation influences germination, aerial mycelium formation and sporulation on solid medium and antibiotic production both, on solid and in liquid medium. Overall, our preliminary results suggest a role for DNA cytosine methylation in morphological and physiological differentiation of S. coelicolor. Further experiments are ongoing to demonstrate the molecular mechanisms and pathways behind the observed phenotypes

Nrtk, ppp or static, that is the question. Testing different positioning solutions for gnss survey

Worldwide, the determination of the coordinates from a Global Navigation Satellite System (GNSS) survey (in Network Real Time Kinematic, Precise Point Positioning, or static mode) has been analysed in several scientific and technical applications. Many of those have been carried out to compare Precise Point Positioning (PPP), Network Real Time Kinematic (NRTK), and static modes’ solutions, usually, using the latter as the true or the most plausible solution. This approach is not always possible as the static mode solution depends on several parameters (baseline length, acquisition time, ionospheric, and tropospheric models, etc.) that must be considered to evaluate the accuracy of the method. This work aims to show the comparison among the GNSS survey methods mentioned above, using some benchmark points. The tests were carried out by comparing the survey methods in pairs to check their solutions congruence. The NRTK and the static solutions refer to a local GNSS CORS network’s analysis. The NRTK positioning has been obtained with different methods (VRS, FKP, NEA) and the PPP solution has been calculated with two different software (RTKLIB and CSRS-PPP). A statistical approach has been performed to check if the distribution frequencies of the coordinate’s residual belong to the normal distribution, for all pairs analysed. The results show that the hypothesis of a normal distribution is confirmed in most of the pairs and, specifically, the Static vs. NRTK pair seems to achieve the best congruence, while involving the PPP approach, pairs obtained with CSRS software achieve better congruence than those involving RTKLIB software

Anthocyanin variation in individual 'Shiraz' berries as affected by exposure and position on the rachis

This study was done on 'Shiraz'/Richter 99 grapes with the intention to define the variation of skin anthocyanin content in a single berry. The effects of berry position (on the rachis), berry exposure, berry weight category, part of the skin of a single berry, and their interactions, were analysed. The anthocyanin concentration of externally facing berries decreased and that of the internally facing berries increased from the apical part to the basal part of the bunch. Highest values were recorded in internally facing berries and lowest values in the externally facing (exposed) berries, of the basal rachis area. Anthocyanin values of small berries seemed to decrease from the apical part of the rachis to the basal part, whereas those of the larger berries generally increased. Anthocyanin distribution in the skin of a single berry was similar for all the berry weight categories. The median concentric layer of the berry showed the highest anthocyanin concentration. The study showed significant intra-berry variation, indicating that even at full ripeness stage there is still variation in every single smaller or larger berry. The results highlighted the very complicated management challenges to grape producers to increase bunch uniformity in quantity and quality.