ABSTRACT Polychaetes are the most diverse group within marine annelids, and they have raised increasing interest in industrial aquaculture especially as an alternative food resource and for developing biotechnological products. This study aimed to analyse information regarding global success in polychaetes aquaculture as a tool for developing sustainable and innovative in Latin America. To achieve this, a systematic review was conducted following the current PRISMA guidelines, analysing articles, reviews and technical reports as open‐access documents, excluding theses, dissertations, presentations and extended abstracts published in English, Portuguese and Spanish up to 2024. The following electronic databases were considered: Elsevier's Scopus, ScienceDirect, SciELO and Google Scholar. This review was structured around the following subtopics: Global Successes in Polychaetes Aquaculture, Polychaetes Aquaculture in Latin America, Development Opportunities for Latin America and Associated Risks. Countries such as the United Kingdom, China, Japan, Taiwan, Korea, Australia and France have experimentally cultured polychaetes and developed derived products for applications in industrial aquaculture, health, cosmetics and pet food. In addition, preliminary studies from countries such as Colombia, Ecuador, Peru, Argentina, Chile, Brazil, Panama and Mexico have been evaluated. Other important aspects for this research were species identification and ecological studies in guiding research and development. This point is especially relevant in Latin American countries where these studies are scarce.
Motivated by [2] and [5], the notions of interior and exterior angles between a pair of compatible intermediate W*-subalgebras of an inclusion of W*-algebras with a normal conditional expectation with finite probabilistic index are introduced. This is then employed effectively to define the interior angle between a pair of compatible intermediate C*-subalgebras of an inclusion of non-unital C*-algebras with a conditional expectation with finite Watatani index. It is also shown that the interior angle is stable under the minimal tensor product of unital C*-algebras.
ABSTRACT Fish like other terrestrial animals, have specific requirements for individual minerals that support the growth and maintenance of normal fish health and other biological functions among different cultured fish species. These minerals can be either macro or micro minerals that are supplied to the fish body through diets or absorbed from their surrounding environment via skins, gills or alimentary tract. However, the bioavailability of these minerals to the fish body is influenced by several factors, including the intake level of the nutrient, interactions with other minerals or nutrients and cultured fish species. To enhance effective bioavailability to the farmed fish, sustainable, healthy and well‐mineral‐balanced diets must be adopted to achieve better fish growth performance, and a high survival rate for high production and productivity while ensuring the resilience of the cultured environment. In this review, the quantitative mineral composition of different mineral sources was reviewed and reported. In addition, mineral requirements in several cultured fish both freshwater and marine water fish species for five macro minerals (calcium, phosphorus, sodium, potassium and magnesium) and seven micro minerals (zinc, iron, copper, manganese, iodine, chromium and selenium) were compiled and reported. Nile tilapia is dominating freshwater cultured species in Tanzania, followed by catfish and rainbow trout, while milkfish is dominating cultured marine species practiced along the coastline from the Northern Tanga region to the Southern Mtwara region. Moreover, this review also covers information on the relationship between minerals and farmed fish, the mechanism of mineral absorption in fish and implications associated with bioavailability of minerals in both aquatic animal body and their surrounding environment, as well as mineral research in future perspectives in the aquaculture industry development. Therefore, the review comprises all this information on the importance of minerals and their bioavailability in farmed fish for sustainable aquaculture production and productivity.
Christopher H. Cashen, Pallavi Dani, Alexandra Edletzberger
et al.
We give criteria for deciding whether or not a triangle-free simple graph is the presentation graph of a right-angled Coxeter group that is quasiisometric to some right-angled Artin group, and, if so, producing a presentation graph for such a right-angled Artin group. We introduce two new graph modification operations, cloning and unfolding, to go along with an existing operation called link doubling. These operations change the presentation graph but not the quasiisometry type of the resulting group. We give criteria on the graph that imply it can be transformed by these operations into a graph that is recognizable as presenting a right-angled Coxeter group commensurable to a right-angled Artin group. In the converse direction we derive coarse geometric obstructions to being quasiisometric to a right-angled Artin group, first by specializing existing results from the literature to this setting, then by developing new approaches using configurations of maximal product regions. In all cases we give sufficient graphical conditions that imply these geometric obstructions. We implemented our criteria on a computer and applied them to an enumeration of small graphs. Our methods completely answer the motiving question when the graph has at most 10 vertices.
Muhammad Faris Allam, Julie Ekasari, Ichsan Achmad Fauzi
et al.
The different carbohydrate complexities are thought to affect the bioavailability of carbon sources for heterotrophic bacteria in the biofloc formation process and produce different biofloc characteristics. Based on these, the purpose of this study was to evaluate the effect of using carbon sources with different levels of complexity on the characteristics and quality of biofloc in pacific white shrimp (Penaeus vannamei) rearing. The carbon sources used in this study were dextrose (DX), potato starch (ST), and α-cellulose (CL). The experimental tests were the TAN (total ammonia nitrogen) reduction test which was carried out for 16 hours and the shrimp rearing test which was carried out for 30 days. Parameters measured to determine the characteristics of biofloc in shrimp rearing test were bifloc volume, biofloc particle size, biofloc nutrient composition, and water quality. The DX treatment produced the lowest TAN in the TAN reduction test. The shrimp rearing test showed the biofloc had different nutrient quality between the treatments. Meanwhile, the water quality between the treatments had relatively close values, but the CL treatment was able to suppress TAN and NO2 lower than the DX and ST treatments during the rearing period. In addition, it is feared that the biofloc volume of the DX treatment which is higher than the ST and CL treatments is feared to be the main cause of stress in shrimp. The conclusion of this study is that complex carbohydrates, especially cellulose, have more potential in improving the performance of the biofloc system.
Keywords: biofloc volume, carbohydrate complexity, nutrient composition, particle size
ABSTRAK
Kompleksitas karbohidrat diduga dapat memengaruhi bioavaibilitas sumber karbon bagi bakteri heterotrof dalam proses pembentukan bioflok, sehingga kompleksitas karbohidrat yang berbeda diduga dapat menghasilkan karakteristik bioflok yang berbeda. Berdasarkan hal tersebut maka tujuan dari penelitian ini adalah untuk mengevaluasi pengaruh penggunaan sumber karbon dengan tingkat kompleksitas yang berbeda terhadap karakteristik dan kualitas bioflok pada pemeliharaan udang vaname (Penaeus vannamei). Sumber karbon yang digunakan dalam penelitian ini adalah dekstrosa (DX), tepung kentang (ST), dan α-selulosa (CL) dan rancangan percobaan yang digunakan adalah RAL (rancangan acak lengkap). Penelitian ini memiliki dua jenis pengujian yang dilakukan secara paralel, yaitu uji penurunan TAN (total ammonia nitrogen) yang dilakukan selama 16 jam dan uji pemeliharaan udang yang dilakukan selama 30 hari. Parameter yang diukur untuk mengetahui karakteristik bioflok pada pemeliharaan udang adalah volume biflok, ukuran partikel bioflok, komposisi nutrien bioflok, dan kualitas air pemeliharaan. Perlakuan DX menghasilkan TAN paling rendah pada uji penurunan TAN. Bioflok yang dihasilkan dari uji pemeliharaan udang menunjukkan kualitas nutrien bioflok yang berbeda-beda antar perlakuanya. Sementara itu kualitas air antar perlakuan memiliki nilai yang relatif berdekatan, tetapi perlakuan CL mampu menekan TAN dan NO2 lebih rendah dari perlakuan DX dan ST selama masa pemeliharran. Selain itu, volume bioflok akhir perlakuan perlakuan DX yang lebih tinggi dari perlakuan ST dan CL dikhawatirkan dapat menjadi penyebab utama stres pada udang. Kesimpulan dari penelitian ini adalah karbohidrat kompleks khususnya selulosa lebih berpotensi dalam meningkatkan performa sistem bioflok.
Kata kunci: kompleksitas karbohidrat, komposisi nutrisi, ukuran partikel, volume bioflok
Schiavon Alfredo, Comoglio Claudio, Candiotto Alessandro
et al.
River flow intermittence is a natural phenomenon intensified by human activities, such as water abstraction and the effects of climate change. A growing number of rivers are predicted to experience intermittent flows, which may impact the diversity and abundance of freshwater species. Dry riverbeds directly diminish the availability of habitats for freshwater organisms, and suitable environments can turn into ecological traps with reduced survival rates, posing a significant threat to population persistence. Even though fish movements can enable drought-affected populations to persist, little is known about individual fish movement between intermittent and perennial reaches. Here, we study the movement of individual PIT-tagged Italian riffle dace (Telestes muticellus) in an intermittent and perennial river reach before, during and after two severe drying events. A high proportion of fish from the intermittent reach survived the drying riverbed through directed upstream migration. This was manifested in fish living in the intermittent reach of the river displaying significantly higher linear ranges, and net travelled distances during the monitoring period than fish in the perennial reach, which remained resident with limited linear range and net distances travelled. This finding underscores the importance of conserving longitudinal river connectivity in the face of increased water scarcity and intermittent flow patterns.
Afaf N. Abdel Rahman, Shimaa R. Masoud, Moustafa M.S. Fouda
et al.
Recently, researchers in aquaculture become interested in green synthesized nanomaterials as a superior alternative to current conventional methodologies. The present work shows that Moringa oleifera synthesized magnetite nanoparticles (MS-Fe3O4NPs) might offer a possible substitute for common antibiotics to treat Aeromonas sobria infection in African catfish (Clarias gariepinus). MS-Fe3O4NPs demonstrated an in vitro antibacterial potential (21 mm inhibition zone) against A. sobria. The fish (n = 120; average body weight: 90 ± 3.5 g) were randomized into four groups (control, MS-Fe3O4NPs, A. sobria, and MS-Fe3O4NPs + A. sobria), where 1.2 mg/L of MS-Fe3O4NPs was used as bath treatment for seven-days. A. sobria infection caused substantial elevations in malondialdehyde, tumor necrosis factor-alpha, stress indices, and hepato-renal biomarkers as well as a lower survival rate. Moreover, an apparent depletion in the level of antioxidants, the protein profile, and immune indicators were the consequences of A. sobria infection. Surprisingly, treatment of A. sobria-infected fish with MS-Fe3O4NPs recovered these parameters. Hence, MS-Fe3O4NPs as a water additive show promise as an antibacterial treatment against A. sobria in fish.
This study investigates the significance of flip angle, an imaging parameter, in enhancing Magnetic Resonance image quality under various imaging conditions. It specifically explores the extent to which the Ernst angle, an optimal flip angle, optimizes image quality under different imaging parameters. The investigation begins with a theoretical derivation of the Ernst angle, assuming steady state imaging conditions. Then multiple studies that examine the effect of flip angle on signal-to-noise ratio (SNR), a key indicator of image quality, in different areas of the human body (blood, liver, and brain), are analysed. The study compares the results of these studies and compares their respective optimal flip angles with the Ernst angle. The findings reveal that flip angle plays a crucial role in enhancing SNR and image quality. However, the Ernst angle only optimizes SNR under steady state conditions and when using a spoiled gradient echo (GRE) sequence. Therefore, further investigations are necessary to determine the optimal flip angle under different imaging conditions to optimize SNR and enhance overall image quality.
Samuel Chable-Naal, Matias Navarro, Didier A Solis
In this work we introduce the notion of constant angle null hypersurface of a Lorentzian manifold with respect to a given ambient vector field. We analyze the case in which the vector field is closed and conformal, thus finding that such null hypersurfaces have a canonical principal direction. We further provide some classification results for constant angle null surfaces with vanishing null mean curvature.