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An unexpected new Metapenaeus shrimp species has arrived to the coastal water of Alexandria City, Egypt. Morphological and molecular studies were conducted for its identification. The results revealed that it is the Indo-West Pacific species, Metapenaeus affinis (H. Milne Edwards, 1837), which is considered as a new addition to the already present local penaeidae species; Metapenaeus monoceros (Fabricius, 1798) and Metapenaeus stebbingi (Nobili, 1904). Large numbers of Metapenaeus affinis were observed and collected by the Egyptian fishermen from the coastal waters of Alexandria City, Egypt, during the study period (2020–2021), which indicates its establishment in the area. A recommendation was presented for further studies regarding the suggested ways of introduction and the prediction for future new species appearance. Such phenomenon requires international efforts to deal with the non-indigenous species’ entries that are recently intensified on the global and regional level.

Africa is a continent that incubates huge inland freshwater reservoirs, representing 27% of total world liquid freshwater, and bounded by marine blue belt. This topography makes Africa harboring diverse freshwater and marine fishery resources. However, fisheries in Africa are still facing big challenges that can be resolved by molecular genetic tools. The present review demonstrated how DNA barcoding approaches expand in African fisheries to solve the problems of fish species identifications, evolutions, population differentiations and biogeographic distributions. Additionally, the limited DNA metabarcoding applications in screening African fish gut microbiome and fish diseases were discussed. Also, we highlighted future perspectives in molecular barcoding applications in African fisheries and a concept for establishing of Africa fish gene bank.

Despite being one of the world’s leading countries in coral reef conservation and management, very little data exist for coral reef-associated species in the island nation of Palau, hampering managers’ ability to more effectively protect coral reef ecosystems. Here we examine populations of the vermetid Ceraesignum maximum, a common species on coral reefs, with short or absent pelagic larval stage, in order to elucidate patterns of gene flow within Palauan reefs. We collected specimens (n = 582) from 20 sites across Palau. Cytochrome oxidase subunit I analyses show private haplotypes at all sites examined, with a clear separation between outer and inner reef locations, and a unique population within isolated Nikko Bay. Oceanographic isolation between the waters of Nikko Bay, inner and outer reefs may contribute to our observed genetic differentiation. Our results indicate past demographic expansion of C. maximum across the region and also indicate that multiple sites of both inner and outer reef locations would need to be protected to conserve this species’ genetic diversity, including unique Nikko Bay. These results demonstrate the utility of C. maximum as a good species to investigate gene flow across small scales (

Recently, tilapia have become increasingly important in aquaculture and fisheries worldwide. They are one of the major protein sources in many African countries and are helping to combat malnutrition. Therefore, maintenance and conservation genetics of wild populations of tilapia are of great significance. In this study, we report the population genetic structure and genetic diversity of the redbelly tilapia (Coptodon zillii) in three different Egyptian aquatic environments: brackish (Lake Idku), marine (Al-Max Bay), and freshwater (Lake Nasser). The habitat differences, environmental factors, and harvesting pressures are the main characteristics of the sampling sites. Three mitochondrial DNA markers (COI: cytochrome oxidase subunit I; the D-loop; CYTB: cytochrome b) were used to assess population structure differences among the three populations. The population at Lake Nasser presented the highest genetic diversity (Hd = 0.8116, H = 6), and the marine population of Al-Max Bay the lowest (Hd = 0.2391, H = 4) of the combined sequences. In addition, the phylogenetic haplotype network showed private haplotypes in each environmental habitat. Results presented here will be useful in aquaculture to introduce the appropriate broodstock for future aquaculture strategies of C. zillii. In addition, evidence of population structure may contribute to the management of tilapia fisheries in Egyptian waters.

In recent years, an increasing number of different JEDEC memory standards, like DDR4/5, LPDDR4/5, GDDR6, Wide I/O2, HBM2, and NVDIMM-P have been specified, which differ significantly from the previous ones like DDR3 and LPDDR3. Since each new standard comes with significant changes in the DRAM protocol compared to the previous ones, the developers of memory controllers and memory simulation models regularly face challenges implementing and verifying these new standards. In order to keep pace with these frequent changes of the requirements and the large variety of variants a robust validation methodology must be established. The JEDEC standards describe the complex memory protocol, i.e., DRAM commands and their timing dependencies, by using a mixture of state machine diagrams, tables, and timing diagrams. However, there exists no unique formal description of the JEDEC standards which could be used for a fast simulation-based validation. In this paper, for the first time, we present a comprehensive and formal mathematical model based on Petri Nets that contains the DRAM states, transitions, and timings. Furthermore, we present a Domain Specific Language (DSL) for describing the memory functionality and timing dependencies of a JEDEC standard in just a few lines of code. From this DSL description an executable Petri Net is generated automatically, which is used for the fast simulation-based validation of memory controllers and DRAM simulation models.

Understanding genetic connectivity is fundamental for ecosystem-based management of marine resources. Here we investigate the metapopulation structure of the edible sea cucumber Holothuria edulis Lesson, 1830 across Okinawa Island, Japan. This species is of economic and ecological importance and is distributed from the Red Sea to Hawai‘i. We examined sequence variation in fragments of mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal RNA (16S), and nuclear histone (H3) at six locations across Okinawa Island. We found higher haplotype diversity for mtDNA (COI: Hd = 0.69 and 16S: Hd = 0.67) and higher heterozygosity of nDNA (H3: H E = 0.39) in populations from the west coast of Okinawa compared to individuals from populations on the east coast (COI: Hd = 0.40; 16S: Hd = 0.21; H3: H E = 0.14). Overall population structure was significant (AMOVA results for COI: Φ ST = 0.49, P

Studies of phylogenetic diversity of fish gut flora often focus on bacteria, leaving a gap in characterization of flora from other domains. This study focused on first exploring of phylogenetic composition of the gut flora, belonging to all domains, eukaryotes, bacteria and archaea, of the tilapia fish, Oreochromis niloticus, inhabiting Lake Nasser, Egypt, based on rRNA gene high-throughput sequencing. Specimens were collected from four distant lake natural fish feeding niches, Khor Kalabsha, Khor Wadi Abyad, Khor Korosko and Khor Toshka. Metagenomic DNA was extracted from fish gut contents, followed by PCR and next generation sequencing of both of eukaryotic 18S- and prokaryotic 16S rRNA genes. A total of 2491, 19005 and 9032 rRNA gene OTUs, were recorded, for eukaryotes, bacteria and archaea, respectively, in the guts from the four niches. Fish guts from Khor Toshka, harbored the highest diversity of bacterial and archaeal 16S rRNA gene sequences. Some 18S rRNA gene OTUs, belonging to members of class Ostracoda, molluscs, and phylum Bacillariophyta, diatoms, beside of 16S rRNA gene OTUs assigned to genus Synechococcus, phylum Cyanobacteria, were recorded in guts from all studied niches, suggesting favorite foods for the fish throughout the lake. Other rRNA gene OTUs, affiliated with the diatom genus Fragilaria, cyanobacterial family Pseudanabaenaceae and genus Oscillatoria, characterized guts from Khor Toshka and Khor Kalabsha, respectively. OTUs, belonging to genus Cetobacterium, phylum Fusobacteria; genera, Methanobacterium and Methanosaeta, phylum Euryarchaeota, constituted the core gut microbiome. Neoechinorhynchus-like OTUs were recorded in guts from all niches, implicating common tilapia gut parasites at Lake Nasser. Guts from all niches harbored several unique archaeal 16S rRNA gene OTUs, but did not match known archaeal phyla. Hence, a large number of phylogenetic shared taxa persist across guts from distant niches, with respect to some OTUs, characterizing gut contents of specific niches.

Processing-in-Memory (PIM) is an emerging approach to bridge the memory-computation gap. One of the key challenges of PIM architectures in the scope of neural network inference is the deployment of traditional area-intensive arithmetic multipliers in memory technology, especially for DRAM-based PIM architectures. Hence, existing DRAM PIM architectures are either confined to binary networks or exploit the analog property of the sub-array bitlines to perform bulk bit-wise logic operations. The former reduces the accuracy of predictions, i.e. Quality-of-results, while the latter increases overall latency and power consumption.In this paper, we present a novel DRAM-based PIM architecture and implementation for multi-bit-precision CNN inference. The proposed implementation relies on shifter based approximate multiplications specially designed to fit into commodity DRAM architectures and its technology. The main goal of this work is to propose an architecture that is fully compatible with commodity DRAM architecture and to maintain a similar thermal design power (i.e. < 1W ). Our evaluation shows that the proposed DRAM-based PIM has a small area overhead of 6.6% when compared with an 8 Gb commodity DRAM. Moreover, the architecture delivers a peak performance of 8.192 TOPS per memory channel while maintaining a very high energy efficiency. Finally, our evaluation also shows that the use of approximate multipliers results in a negligible drop in prediction-accuracy (i.e. < 2 %) in comparison with conventional CNN inference that relies on traditional arithmetic multipliers.

This paper presents a novel ferroelectric field-effect transistor (FeFET) in-memory computing architecture dedicated to accelerate Binary Neural Networks (BNNs). We present in-memory convolution, batch normalization and dense layer processing through a grid of small crossbars with reduced unit size, which enables multiple bit operation and value accumulation. Additionally, we explore the possible operations parallelization for maximized computational performance. Simulation results show that our new architecture achieves a computing performance up to 2.46 TOPS while achieving a high power efficiency reaching 111.8 TOPS/Watt and an area of 0.026 mm2 in 22nm FDSOI technology.