An Overview of Recent Changes in the Global Maritime Distress and Safety System Regarding Maritime Mobile Satellite Service

For a long time, Inmarsat satellite system was the only maritime mobile satellite service provider when Global Maritime Distress and Safety System (GMDSS) is concerned. This satellite system has different generations of its satellites providing a wide range of services and applications. In 2018, its services related to the GMDSS have migrated to a newer generation of satellites. This satellites’ services migration is systematically discussed and analysed in this paper in order to familiarize the readers with its effects on the safety of navigation. Furthermore, Inmarsat system announced a new service called Inmarsat Fleet Safety which will incorporate and provide all functional requirements for the GMDSS which are currently provided by Inmarsat-C and Inmarsat Fleet 77 terminals. However, in 2018 a new satellite system called Iridium has been recognized as a mobile satellite communication services provider in the GMDSS. Accordingly, this system and its capabilities are also introduced and briefly described in this paper. In addition, authors have discussed impacts of the introduction of the new satellite system as a service provider in the GMDSS and addressed several emphasized issues related to this GMDSS modernization

IMOTOX - Identification and Monitoring of Toxic Cyanobacteria

Blooms of harmful cyanobacteria have been shown to increase in both frequency and severity due to global warming, particularly through increased nutrient loads at extreme weather events with elevated winter/spring rainfall and flushing events followed by extended periods of summer drought. These blooms threaten our shrinking freshwater resources in several ways: By increasing turbidity and consequently depriving submerged plants of light they suppress invertebrate and fish habitats and can thus affect biodiversity. On the other hand, release of cyanotoxins during blooms can cause problems for fisheries, drinking water reservoirs as well as recreational water activities. This project aims to develop a monitoring and early warning system for cyanobacterial blooms, and study factors that influence bloom formation, toxicity and collapse. This will be achieved through a close interaction of molecular microbiology, analytical chemistry and remote sensing technology. The early detection of the rise of potentially harmful cyanobacteria in freshwater lakes will be achieved by remote sensing, followed by a targeted molecular, microbial and chemical verification which in turn will allow time for taking appropriate counter measures

Microbiote et santé (caractérisation d'activités fibrolytiques aun sein du microbiote iléal de l'Homme)

Le microbiote intestinal est représenté par une population microbienne anaérobie complexe et très diversifiée, responsables de nombreuses activités métaboliques. Les bactéries fibrolytiques, par exemple, jouent un rôle important dans la dégradation des fibres alimentaires. L'activité de dégradation de ces fibres alimentaires a été clairement démontrée dans le gros intestin mais semble également importante au niveau de l'iléon. Cependant, à ce jour, le potentiel génétique du microbiote iléal n'a pas été élucidé pour la dégradation de glucides complexes tels que les polysaccharides constitutifs des fibres alimentaires. Deux clones métagénomiques d'intérêt, possédant des activités cellulase et xylanase, ont été sélectionnés au sein d'une banque métagénomique iléo-mucosale. Grâce à des études bioinformatiques et la comparaison de leur séquence avec les gènes et génomes de référence du projet MetaHit, ces deux clones ont été identifiés comme appartenant respectivement aux espèces Bacteroides uniformis et Eubacterium rectale, deux bactéries connues pour leurs activités de dégradation des fibres alimentaires dans l'intestin. La prépondérance des protéines portées par ces clones a été déterminée au sein de 884 individus. Plusieurs glycoside hydrolases (CAZymes) sont retrouvées sur les séquences de ces clones, et sont potentiellement responsables des activités enzymatiques observées. Les gènes correspondants ont été étudiés par mutagenèse par transposition et sous-clonage, puis des tests d'activité enzymatique ont été réalisés à partir des extraits bactériens et extracellulaires des clones recombinants. Ces études ont permis de mettre en évidence la responsabilité de deux glycoside hydrolases spécifiques, possédant une double activité cellulase et xylanase, ce qui démontre qu'il existe des microorganismes capables de dégrader les fibres alimentaires au niveau de la muqueuse iléale chez l'Homme.CHATENAY M.-PARIS 11-BU Pharma. (920192101) / SudocSudocFranceF

Pulse-Controlled Amplification-A new powerful tool for on-site diagnostics under resource limited conditions.

BackgroundMolecular diagnostics has become essential in the identification of many infectious and neglected diseases, and the detection of nucleic acids often serves as the gold standard technique for most infectious agents. However, established techniques like polymerase chain reaction (PCR) are time-consuming laboratory-bound techniques while rapid tests such as Lateral Flow Immunochromatographic tests often lack the required sensitivity and/or specificity.Methods/principle findingsHere we present an affordable, highly mobile alternative method for the rapid identification of infectious agents using pulse-controlled amplification (PCA). PCA is a next generation nucleic acid amplification technology that uses rapid energy pulses to heat microcyclers (micro-scale metal heating elements embedded directly in the amplification reaction) for a few microseconds, thus only heating a small fraction of the reaction volume. The heated microcyclers cool off nearly instantaneously, resulting in ultra-fast heating and cooling cycles during which classic amplification of a target sequence takes place. This reduces the overall amplification time by a factor of up to 10, enabling a sample-to-result workflow in just 15 minutes, while running on a small and portable prototype device. In this proof of principle study, we designed a PCA-assay for the detection of Yersinia pestis to demonstrate the efficacy of this technology. The observed detection limits were 434 copies per reaction (purified DNA) and 35 cells per reaction (crude sample) respectively of Yersinia pestis.Conclusions/significancePCA offers fast and decentralized molecular diagnostics and is applicable whenever rapid, on-site detection of infectious agents is needed, even under resource limited conditions. It combines the sensitivity and specificity of PCR with the rapidness and simplicity of hitherto existing rapid tests

Analysis of photosynthetic picoeukaryote diversity at open ocean sites in the Arabian Sea using a PCR biased towards marine algal plastids

Marine photosynthetic picoeukaryotes (PPEs), representing organisms < 3 mu m in size, are major contributors to global carbon cycling. However, the key members of the PPE community and hence the major routes of carbon fixation, particularly in the open ocean environment, are poorly described. Here, we have accessed PPE community structure using the plastid encoded 16S rRNA gene. Plastid 16S rRNA genes were sequenced from 65 algal cultures, about half being PPEs, representing 14 algal classes. These included sequences from 5 classes where previously no such sequences from cultured representatives had been available (Bolidophyceae, Dictyochophyceae, Eustigmatophyceae, Pelagophyceae and Pinguiophyceae). Sequences were also obtained for 6 of the 7 (according to 18S rRNA gene sequence) prasinophyte clades. Phylogenetic analysis revealed plastids from the same class as clustering together. Using all the obtained sequences, as well as plastid sequences currently in public databases, a non-degenerate marine algal plastid-biased PCR primer, PLA491F, was developed to minimize amplification of picocyanobacteria, which often dominate numerically environmental samples. Clone libraries subsequently constructed from the pico-sized fraction from 2 open ocean sites in the Arabian Sea, revealed an abundance of 16S rRNA gene clones phylogenetically related to chrysophytes, whilst prymnesiophyte, clade II prasinophyte (Ostreococcus-like) and pelagophyte clones were also well represented. The finding of a wealth of novel clones related to the Chrysophyceae highlights the utility of a PCR biased towards marine algal plastids as a valuable complement to 18S rDNA based studies of PPE diversity

Temporal Dynamics of the Microbial Community Composition with a Focus on Toxic Cyanobacteria and Toxin Presence during Harmful Algal Blooms in Two South German Lakes

Bacterioplankton plays an essential role in aquatic ecosystems, and cyanobacteria are an influential part of the microbiome in many water bodies. In freshwaters used for recreational activities or drinking water, toxic cyanobacteria cause concerns due to the risk of intoxication with cyanotoxins, such as microcystins. In this study, we aimed to unmask relationships between toxicity, cyanobacterial community composition, and environmental factors. At the same time, we assessed the correlation of a genetic marker with microcystin concentration and aimed to identify the main microcystin producer. We used Illumina MiSeq sequencing to study the bacterioplankton in two recreational lakes in South Germany. We quantified a microcystin biosynthesis gene (mcyB) using qPCR and linked this information with microcystin concentration to assess toxicity. Microcystin biosynthesis gene (mcyE)-clone libraries were used to determine the origin of microcystin biosynthesis genes. Bloom toxicity did not alter the bacterial community composition, which was highly dynamic at the lowest taxonomic level for some phyla such as Cyanobacteria. At the OTU level, we found distinctly different degrees of temporal variation between major bacteria phyla. Cyanobacteria and Bacteroidetes showed drastic temporal changes in their community compositions, while the composition of Actinobacteria remained rather stable in both lakes. The bacterial community composition of Alpha- and Beta-proteobacteria remained stable over time in Lake Klostersee, but it showed temporal variations in Lake Bergknappweiher. The presence of potential microcystin degraders and potential algicidal bacteria amongst prevalent Bacteroidetes and Alphaproteobacteria implied a role of those co-occurring heterotrophic bacteria in cyanobacterial bloom dynamics. Comparison of both lakes studied revealed a large shared microbiome, which was shaped toward the lake specific community composition by environmental factors. Microcystin variants detected were microcystin-LR, -RR, and -YR. The maximum microcystin concentrations measured was 6.7 μg/L, a value still acceptable for recreational waters but not drinking water. Microcystin concentration correlated positively with total phosphorus and mcyB copy number. We identified low abundant Microcystis sp. as the only microcystin producer in both lakes. Therefore, risk assessment efforts need to take into account the fact that non-dominant species may cause toxicity of the blooms observed

Comparative sensitivity evaluation for 122 CE-marked rapid diagnostic tests for SARS-CoV-2 antigen, Germany, September 2020 to April 2021

INTRODUCTION: Numerous CE-marked SARS-CoV-2 antigen rapid diagnostic tests (Ag RDT) are offered in Europe, several of them with unconfirmed quality claims. AIM: We performed an independent head-to-head evaluation of the sensitivity of SARS-CoV-2 Ag RDT offered in Germany. METHODS: We addressed the sensitivity of 122 Ag RDT in direct comparison using a common evaluation panel comprised of 50 specimens. Minimum sensitivity of 75% for panel specimens with a PCR quantification cycle (Cq) ≤ 25 was used to identify Ag RDT eligible for reimbursement in the German healthcare system. RESULTS: The sensitivity of different SARS-CoV-2 Ag RDT varied over a wide range. The sensitivity limit of 75% for panel members with Cq ≤ 25 was met by 96 of the 122 tests evaluated; 26 tests exhibited lower sensitivity, few of which failed completely. Some RDT exhibited high sensitivity, e.g. 97.5 % for Cq &lt; 30. CONCLUSIONS: This comparative evaluation succeeded in distinguishing less sensitive from better performing Ag RDT. Most of the evaluated Ag RDT appeared to be suitable for fast identification of acute infections associated with high viral loads. Market access of SARS-CoV-2 Ag RDT should be based on minimal requirements for sensitivity and specificity

Results of t-tests for between-sites differences in stable isotope values of vent fauna at the East Scotia Ridge.

*<p>Welch’s t-test,</p>Ψ<p>Wilcoxon test.</p