Hasil untuk "Aquaculture. Fisheries. Angling"

A. Tacon, M. Metian

Cong Wang, Zhen Li, Tan Wang et al.

With the continuous expansion of aquaculture scale and density, contemporary aquaculture methods have been forced to overproduce resulting in the accelerated imbalance rate of water environment, the frequent occurrence of fish diseases, and the decline of aquatic product quality. Moreover, due to the fact that the average age profile of agricultural workers in many parts of the world are on the higher side, fishery production will face the dilemma of shortage of labor, and aquaculture methods are in urgent need of change. Modern information technology has gradually penetrated into various fields of agriculture, and the concept of intelligent fish farm has also begun to take shape. The intelligent fish farm tries to deal with the precise work of increasing oxygen, optimizing feeding, reducing disease incidences, and accurately harvesting through the idea of “replacing human with machine,” so as to liberate the manpower completely and realize the green and sustainable aquaculture. This paper reviews the application of fishery intelligent equipment, IoT, edge computing, 5G, and artificial intelligence algorithms in modern aquaculture, and analyzes the existing problems and future development prospects. Meanwhile, based on different business requirements, the design frameworks for key functional modules in the construction of intelligent fish farm are proposed.

Mónica Vanessa Oviedo-Olvera, Ana Angélica Feregrino-Pérez, María Isabel Nieto-Ramírez et al.

The accelerated growth of aquaculture has encouraged the search for new techniques and inputs to increase the yield of various aquaculture species, considering the health and welfare of the organisms. Functional food development for fish nourishment includes ingredients containing bioactive compounds, such as prebiotics, that generate favorable immune responses. Non-digestible oligosaccharides function as growth promoters of the intestinal microbiota, improving nutrient absorption and enhancing the fish immune system. Therefore, the inclusion of new prebiotic-rich ingredients in the feed of aquatic organisms has generated interest. This article reviews the use of microalgae and insects as functional ingredients which provide quality macronutrients and contain different bioactive compounds that have been reported to have immunostimulatory effects. Their chemical composition is described, and their potential use as prebiotics for developing functional food for aquaculture is discussed.

Benjamin William Van Alen

ABSTRACT Is there an ecological niche for ‘ocean ranched’ hatchery salmon, Oncorhynchus spp., to supplement wild salmon? Ecologically, I hypothesize that the carrying capacity for biota is: (1) limited; (2) filled with locally adapted biota competing and cooperating to nurture viable offspring; and (3) sustained by the biogeochemical recycling of their nutrient elements. Thus, biotic abundance is limited more by the space and food needed to nurture viable adults than by the numbers reproduced. Hatchery immigrants compete for space and food with wild biota, spawn with and reduce the fitness and biodiversity of wild salmon, and their growth and commercial harvest consume more biogeochemical resources than they recycle. This contributes directly to ecological overshoot and to the declining or depressed populations of wild salmon, Pacific herring Clupea pallasi and eulachon Thaleichthys pacificus now observed in Southeast Alaska and wherever there are production releases of hatchery salmon. Industrial‐scale hatcheries do not have a niche in sustainable salmon management.

Yameng Song, Mengyao Wu, Yongxu Cheng et al.

Conclusion: Gly has certain effects on the digestive tissue function, intestinal microbial diversity index and intestinal microbiota structure of E. sinensis, and MA can ameliorate the negative effects of Gly on E. sinensis.

Kurhaluk Natalia, Grudniewska Joanna, Tkaczenko Halina

The present study was performed to investigate the effects of dietary yeast β-1,3/1,6-D-glucans after 15-, 30-, and 45-day feeding periods on the development of oxidative stress, antioxidant defenses, and lysosomal functioning in gills and hepatic tissue of rainbow trout, Oncorhynchus mykiss (Walbaum). The fish were fed a control diet or an experimental diet containing the supplement Yestimun® at a dose of 1% in the basal feed (with 85% content of β-1,3/1,6-glucans). On days 15, 30, and 45 of the experiment, the following were analyzed in gills and hepatic tissue: oxidative stress biomarkers (2-thiobarbituric-acid-reacting substances [TBARS]); aldehydic and ketonic derivatives of oxidatively modified proteins; activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GPx); total antioxidant capacity (TAC); activities of lysosomal enzymes (alanyl aminopeptidase [AAP], leucyl aminopeptidase [LAP], acid phosphatase [AcP], β-N-acetylglucosaminidase [NAG]). The dietary β-glucans stimulated CAT, GPx, LAP, and AcP activities in gills and hepatic tissue compared to the control group; however, the opposite trend was observed in TAC levels in gills on days 30 and 45. The present study suggests that β-glucans can enhance immune response, antioxidant capacity, and lysosomal functioning effectively in rainbow trout.

Qingsong Zeng, Yunxiao Sun, Peifang Lai et al.

Frazen Tolentino-Zondervan, P. Ngoc, J. L. Roskam

Â. P. Matos, Andressa Coimbra Pereira, A. Perretta et al.

Fedor K. Popov, Grigory Tarnopolsky

We consider a configuration of three stacked graphene monolayers with equal consecutive twist angles $θ$. Remarkably, in the chiral limit when interlayer coupling terms between $\textrm{AA}$ sites of the moiré pattern are neglected we find four perfectly flat bands (for each valley) at a sequence of magic angles which are exactly equal to the twisted bilayer graphene (TBG) magic angles divided by $\sqrt{2}$. Therefore, the first magic angle for equal-twist trilayer graphene (eTTG) in the chiral limit is $θ_{*} \approx 1.05^{\circ}/\sqrt{2} \approx 0.74^{\circ}$. We prove this relation analytically and show that the Bloch states of the eTTG's flat bands are non-linearly related to those of TBG's. Additionally, we show that at the magic angles, the upper and lower bands must touch the four exactly flat bands at the Dirac point of the middle graphene layer. Finally, we explore the eTTG's spectrum away from the chiral limit through numerical analysis.

Wara Dyah Pita Rengga, Erika Wijayanti, Yoga Agung Prabowo et al.

Limbah cangkang udang menimbulkan permasalahan polusi udara dan tumpukan sampah yang dihinggapi lalat. Pemanfaatan cangkang udang yang kaya protein dapat diekstraksi untuk dimanfaatkan sebagai serbuk penyedap rasa. Penelitian ini dilakukan untuk menentukan karakteristik dari filtrat ekstrak cangkang udang segar dan produk serbuk rasa udang, serta menentukan kondisi ekstraksi yang optimal pada penggunaan konsentrasi bromelain dan waktu refluk. Metode yang digunakan untuk pengambilan ekstrak udang dengan cara ekstraksi dengan alat refluk yang dilengkapi dengan pendingin yang terbagi menjadi dua tahap yaitu penambahan larutan garam dan enzim bromelain Gabungan filtrat ekstraksi dianalisis menggunakan GC-MS dan FT-IR. Selanjutnya filtrat diformulasikan menjadi serbuk penyedap rasa udang dengan beberapa bahan tambahan berupa tepung dan rempah-rempah. Selanjutnya, serbuk penyedap rasa dianalisis kadar air dan TEM. Ekstrak cangkang udang segar yang dianalsis mengandung senyawa dimetilamina dan trimetilamina yang merupakan kandungan protein, dengan kadar protein mencapai 28,984%. Selain protein, ekstrak juga mengandung asam lemak cangkang udang. Serbuk penyedap rasa udang yang dihasilkan mempunyai ukuran partikel sebesar 5 s.d 25 nm, dengan kadar air 11,11%. Kondisi operasi optimal ekstraksi protein dengan metode refluk pada kombinasi konsentrasi 2% katalis enzim bromelain pada suhu refluks 55 °C selama 1,5 jam. Ekstraksi menggunakan enzim bromelain secara bertahap memberikan kualitas flavor udang berupa serbuk kandungan protein dan lemak udang yang dipadu menjadi cita rasa spesifik dengan ukuran nanometer.

M. Kumaran, R. Geetha, J. Antony et al.

The lockdown on account of the Coronavirus disease 2019 (COVID-19) adversely impacted the food production sector including aquaculture, globally. Unfortunately, it coincided with the major shrimp farming season in India which contributes 60% of the national annual shrimp production hence the impact was substantial. An on-line survey was carried out among the stakeholders of the shrimp farming sector to evaluate the prospective impact of COVID-19 related lockdown across the shrimp supply chain. The study estimated an economic loss of 1.50 billion USD to the shrimp aquaculture sector during the current year. It is expected that shrimp production and its export performance may be declining by 40% in the current season. The Garret ranking and Rank Based Quotient analyses projected severe constraints in shrimp seed production and supply, disruptions in the supply chain, logistics, farming, processing, marketing and loss of employment and income for the workers due to the pandemic. To mitigate the impact, the Government of India declared fisheries and aquaculture as an essential activity, facilitated the movement of inputs and services. Further, a major Fisheries Development Scheme(PMMSY) with a financial outlay of 267 million USD has been announced to usher in a blue revolution by strengthening the value chain, doubling the fisher/farmer income, employment generation, economic and social security for fishers/fish farmers adhering to the sustainability principles. Short and medium-term technical and policy measures are suggested to tide over the impact of COVID-19 related lockdown and related restrictions.

Yilin Zhang, Songshan Yang

Measuring and testing dependence between complex objects is of great importance in modern statistics. Most existing work relied on the distance between random variables, which inevitably required the moment conditions to guarantee the distance is well-defined. Based on the geometry element ``angle", we develop a novel class of nonlinear dependence measures for data in metric space that can avoid such conditions. Specifically, by making use of the reproducing kernel Hilbert space equipped with Gaussian measure, we introduce kernel angle covariances that can be applied to complex objects such as random vectors or matrices. We estimate kernel angle covariances based on $U$-statistic and establish the corresponding independence tests via gamma approximation. Our kernel angle independence tests, imposing no-moment conditions on kernels, are robust with heavy-tailed random variables. We conduct comprehensive simulation studies and apply our proposed methods to a facial recognition task. Our kernel angle covariances-based tests show remarkable performances in dealing with image data.

Sam Shepherd

Let $Γ$ be a graph product of finite groups, with finite underlying graph, and let $Δ$ be the associated right-angled building. We prove that a uniform lattice $Λ$ in the cubical automorphism group Aut$(Δ)$ is weakly commensurable to $Γ$ if and only if all convex subgroups of $Λ$ are separable. As a corollary, any two finite special cube complexes with universal cover $Δ$ have a common finite cover. An important special case of our theorem is where $Γ$ is a right-angled Coxeter group and $Δ$ is the associated Davis complex. We also obtain an analogous result for right-angled Artin groups. In addition, we deduce quasi-isometric rigidity for the group $Γ$ when $Δ$ has the structure of a Fuchsian building.

Bilgen Akmermer, Pelin Çelik

Fisheries and aquaculture industry, which provides a continuous and high-return market advantage to potential countries, is also one of the priority industries for Turkey. Although Turkey has important advantages with its geographic position and bio-diversity, the industry's contribution to foreign trade is not at an acceptable level. Accordingly, it is important to evaluate the capture fishery and aquaculture products, which provide the best contribution to the foreign trade of Turkey. Thus, the present paper aims to provide foreign trade executives with an intuition about the most appropriate products to invest in and contributing products to Turkish foreign trade within the scope of market strategies. Entropy-WASPAS, which is a hybrid multi-criteria decision-making method, is used for evaluating the contribution of fishery and aquaculture products to Turkish foreign trade. This model includes both criteria (production, import quantity, import value, export quantity, export value) and alternatives (trout, sea bream, sea bass, sprat, atlantic bonito, anchovy, horse mackerel, pilchard, sea snail, prawn, cuttle fish, mussel). Entropy is used to determine the criteria weights, and WASPAS is applied for ranking the fishery and aquaculture products. According to the results, export value is the most important criteria while Sea Bream is found as the most significant product for Turkey’s foreign trade.

Jonathan Wurtz, Danylo Lykov

The quantum approximate optimization algorithm (QAOA) is a near-term combinatorial optimization algorithm suitable for noisy quantum devices. However, little is known about performance guarantees for $p>2$. A recent work \cite{Wurtz_guarantee} computing MaxCut performance guarantees for 3-regular graphs conjectures that any $d$-regular graph evaluated at particular fixed angles has an approximation ratio greater than some worst-case guarantee. In this work, we provide numerical evidence for this fixed angle conjecture for $p<12$. We compute and provide these angles via numerical optimization and tensor networks. These fixed angles serve for an optimization-free version of QAOA, and have universally good performance on any 3 regular graph. Heuristic evidence is presented for the fixed angle conjecture on graph ensembles, which suggests that these fixed angles are ``close" to global optimum. Under the fixed angle conjecture, QAOA has a larger performance guarantee than the Goemans Williamson algorithm on 3-regular graphs for $p\geq 11$.

Guilherme Raphael Camargo Arcanjo SILVA, Maurício CETRA

Several tropical freshwater fish species are generally generalistic feeders, sometimes followed by a diet reduction during the period of decreased resource availability. This study aimed to analyze the dietary overlap between nektonic and benthic fish species. The stomachs of 82 obligatory nektonics and 52 benthic were removed. The diet composition for each individual was determined based on the analysis of the stomach content, and the contents were grouped into 11 categories. For the analysis of food items, the method of degree of food preference was used. To verify the niche overlap between benthic and nectonic, the Pianka index was applied. Benthic species consumed items across all 11 food categories and nektonic species consumed nine. The diet composition of species with nektonic and benthic habits showed a significant difference. Dietary overlapping suggests a supply of the same resources, as they are shared by both groups. The high concentration of water insect larvae in the food content of all sampled fish species, regardless of the position in the water column, shows the importance of insects in the water ecosystems. The composition of ecosystem diets is helpful towards understanding the community structure and can explain the coexistence between different fish’s groups where live in different micro-habitats and how tactics used to capture food which may minimize the effects of overlapping and competitive exclusion.

M. T. M. Mutia, Myleen L. Magistrado, Michelle Joy L. Fermaran et al.

Lake Taal is a source of livelihood and provides for more than 2,000 sustenance fisherfolk. Fish production of the open water fisheries has dwindled over the years with the continuous decline of fish catch, which can be attributed to unsustainable fishing practices such as illegal fishing, overfishing, pollution, and the expansion of aquaculture activities in the lake. Women, as a sector, constitute almost one half of the economically active population in Lake Taal. Men and women performed different roles at different stages of fish capture or fish culture. In terms of their economic and social value, the participation of women in pre- and post-production activities are significant. This study assessed the level of gender participation in the fisheries sector of Lake Taal. Specifically, it determined the roles of men and women in the different fishing activities and described the fisherfolk’s socioeconomic profile. A total of 407 randomly selected respondents were interviewed in 11 barangays from eight municipalities in Lake Taal, represented by 54% male and 46% female, consisting of 214 fishers, 76 fish vendors, four processors, 51 helpers, and 62 fish cage or fish pond owners, managers, and caretakers. Profiling of the socioeconomic status was done to assess families’ living conditions and constructed primary data based on household’s present roles, activities, responsibilities, access to and control over resources, problems, and constraints of men and women. The roles of both men and women in fisheries were categorized into three sectors: capture, post-harvest, and aquaculture.

M. Bondad‐Reantaso

Since the adoption, in May 2015, of the Global Plan of Action (GAP) on Antimicrobial Resistance (AMR), during the 68th World Health Assembly of the World Health Organization (WHO) and the subsequent adoption by the delegates of the World Organisation for Animal Health (OIE) of the OIE AMR Strategy and the adoption of Resolution 4/2015 by the 39 Conference of the Food and Agriculture Organization of the United Nations (FAO), a political declaration was made during a high-level meeting on AMR at the 71st United Nations General Assembly (UNGA, September 2016). The UNGA called upon the Tripartite (i.e. WHO, OIE, and FAO) and other intergovernmental organisations to support the development and implementation of National Action Plans (NAPs) and AMR activities at the national, regional, and global levels under the One Health platform. This paper provides preliminary guidance in the development of the aquaculture component of NAP on AMR under the auspices of the FAO project FMM/RAS/298/MUL: Strengthening capacities, policies, and national action plans on prudent and responsible use of antimicrobials in fisheries. Such guidance, consisting of two levels (i.e. generic and aquaculture-specific), are important first steps in the process. Having such a plan will now allow the responsible Competent Authority to raise the profile of aquaculture in national discourses on AMR, generate an understanding of the sector and its importance by other relevant sectors engaged in the One Health platform, stimulate investment and support towards further development and implementation of the action plan. The aquaculture component needs to be fully integrated in a country’s NAP on AMR.

Wenzhao Li, C. J. O. Reichhardt, B. Jankó et al.

We examine pinning and dynamics of Abrikosov vortices interacting with pinning centers placed in a moiré pattern for varied moiré lattice angles. We find a series of magic angles at which the critical current shows a pronounced dip corresponding to lattices in which the vortices can flow along quasi-one-dimensional channels. At these magic angles, the vortices move with a finite Hall angle. Additionally, for some lattice angles there are peaks in the critical current produced when the substrate has a quasiperiodic character that strongly reduces the vortex channeling. Our results should be general to a broad class of particle-like assemblies moving on moiré patterns.