Fishing Line Research Articles

D-Amphetamine and Feeding States Cohesively Affect Locomotion and Motor Neuron Response in Zebrafish Larvae.

Amphetamine (AMPH) increases locomotor activities in animals, and the locomotor response to AMPH is further modulated by caloric deficits such as food deprivation and restriction. The increment in locomotor activity regulated by AMPH-caloric deficit concomitance can be further modulated by varying feeding schedules (e.g., acute and chronic food deprivation and acute feeding after chronic food deprivation). However, the effects of different feeding schedules on AMPH-induced locomotor activity are yet to be explicated. Here, we have explored the stimulatory responses of acutely administered D-amphetamine in locomotion under systematically varying feeding states (fed/sated and food deprivation) and schedules (chronic and acute) in zebrafish larvae. We exposed wild-type and transgenic [Tg(mnx1:GCaMP5)] zebrafish larvae to 0.7µM concentration of AMPH and measured swimming activity and spinal motor neuron activity in vivo in real time. The analysis involved time-elapsed and cumulative manner pre- and post-AMPH treatment in four different caloric states including acute and chronic schedules of feeding and hunger. Both locomotor and motor neuron activities were compared in all four states in both fish lines. Our results show that locomotion and motor neuron activity increased in both chronic and acute food deprivation post-AMPH treatment cumulatively. A steady increase in locomotion was observed in acute food deprivation compared to an immediate abrupt increase in chronic food-deprivation state. The ad libitum-fed larvae exhibited a moderate increase both in locomotion and motor neuron activity. Conversely to all other caloric states, food-sated (acute feeding after chronic food deprivation) larvae moved moderately less and exhibited a mild decrease in motor neuron activity after AMPH treatment. These results reveal the importance of cohesive effects of feeding schedule and AMPH treatment by revealing the changes in stimulatory characteristics of AMPH on locomotion and motor neuron activity in acute and chronic feeding states.

Multi-layered morphing soft structure with high-performance embedded electrothermal artificial muscles along with touch and temperature sensors

Abstract In this paper, we present a novel multilayered morphing structure, having similar topology resembling the structures found in nature to grasp delicate objects effectively as well as sense contact force and temperature. The structure consists of two actuation layers, two U-shaped cooling channel layers, piezoelectric based touch sensors and temperature sensors. Employing shape memory alloy (SMA) spring actuators for bending and twisted and coiled polymer fishing line with nichrome (TCPFL NMC) artificial muscles for antagonistic return, the soft silicone-based composite skin exhibits unique capabilities of large bidirectional movement, avoid rigid passive springs for return motion, soft grasping, safe interaction with humans, and ease fabrication. The SMA (0.38 mm wire diameter) serves as relatively fast actuating muscle and the TCPFL NMC (0.8 mm fiber diameter) as a slow actuating (considering mainly heating cycle), which was programmed/designed to mimic the fast and slow twitching muscles found in nature. Bending and return operations of skin samples of length 100 mm and thickness of 9 mm, with three different widths 20 mm, 25 mm, 30 mm, were experimentally studied. The 25 mm wide multilayered soft skin demonstrated cyclic actuation with a maximum bending angle of ∼70°, which was attributed due to the active cooling. The fluidic channels for active cooling were fabricated using 3D printed PVA tubes, casting within the silicone in a mold and subsequently dissolving in a circulating water. The study also included the integration and voltage response of mini-piezodisk sensor PIC255 having a diameter of 2 mm and thickness of 0.15 mm, which was embedded at different depths within the silicone (on the surface, 1 mm depth and 2 mm depth). The multilayered soft skin was also able to detect the temperature of the object during grasping, suggesting its potential application as a soft gripper in robotic systems.

Exploring the Sources of Marine Debris and their Effects on Magogoni Ferry Operations Efficiency

Marine debris poses significant challenges to the operational efficiency of the Magogoni Ferry in Dar es Salaam, Tanzania. This study investigates the sources of marine debris in the ferry's operational environment and evaluates their effects on operational efficiency. Field surveys, interviews, observations, and document reviews were conducted to identify debris sources and quantify their impacts on ferry operations. Findings indicate diverse debris origins, including urban waste, coastal littering, and shipping activities, contributing to operational disruptions through increased maintenance needs and service delays. The study underscores the importance of debris management strategies for sustaining ferry operations. It was found that a large quantity of marine debris reaching the Magogoni Ferry was brought by rivers during the rainy seasons, namely River Tegeta, River Mzinga, and River Msimbazi. Marine debris which impairs ferry operations at Magogoni Ferry includes fishing lines, fishing nets, wood, ropes, textiles, and plastic bags. The effects were seal damage, pump jet blockage, impeller entanglement, mechanical obstruction of the pump jet, and engine stoppage. These breakdowns cause navigational hazards, environmental pollution due to oil leakages, and increased costs of maintenance. It was found that between 2019 and 2023, the cost of maintenance due to breakdowns, whose sources were established to be marine debris, amounted to an average of Tsh120 million per year. to ensure the ferry channel is safe for navigation it was recommended to make it free from debris through implementing educational campaigns to raise awareness, regular cleaning, prohibiting fishing by angling near the ferry area, and the use of technology both to block the entrance of land-based waste to the sea and to improve ferry systems by making them able to withstand debris challenges, for example, the introduction of cutting blades to cut nets, ropes, and fishing lines, protecting the propulsion components.

UBE2J1 suppresses interferon signaling by facilitating the ubiquitination and degradation of IRF7

Ubiquitin-binding enzyme E2J1 (UBE2J1) is a predominant member of the UBE2 family. In mammals, it is involved in antiviral immunity, ER-misfolded protein degradation, and ubiquitination. However, the function of UBE2J1 in teleost has not been elucidated. In the present study, we cloned the homolog of UBE2J1 in triploid hybrid fish and investigated its regulatory role in the antiviral interferon (IFN) signaling. We determined that the full-length coding sequence of the triploid fish UBE2J1 (3nUBE2J1) consists of 939 base pairs and encodes 313 amino acids. Upon SVCV infection, the mRNA levels of 3nUBE2J1 were increased in the spleen, liver, kidney, and the caudal fin cell line of triploid fish. Knockdown of 3nUBE2J1 in host cells and fish enhanced their antiviral response and curtailed SVCV replication. Conversely, overexpression of 3nUBE2J1 inhibited the activation of IFN promoter induced by SVCV, poly (I:C), or RLR pathway factors. Further studies revealed that 3nUBE2J1 interacted with 3nIRF7 and suppressed both the protein level and antiviral activity of 3nIRF7. Finally, we demonstrated that 3nUBE2J1 enhanced the K27- and K29-linked ubiquitination of 3nIRF7, leading to its degradation. Collectively, our findings indicate that triploid fish UBE2J1 serves as a novel negative regulator of IFN signaling by inhibiting 3nIRF7.

Enhancing coral restoration practices in Seychelles: benefits and limitations of fishing lines and rope as coral stocking methods

Coral restoration plays a pivotal role in mitigating the decline of coral reefs, increasing the need for implementing effective techniques and methodologies. This study investigates the efficacy of stocking Acropora muricata and Pocillopora grandis using fishing line versus rope in mid‐water floating nurseries, offering valuable insights for coral restoration practitioners. Over 1 year, survival, tissue cover, growth, cleaning time, cost, preparation, and stocking timing for both methods were evaluated. Fishing line reduced contact with fouling organisms, contributing to enhanced coral tissue cover and growth rates for P. grandis compared to rope, but no significant effect was detected for A. muricata. Survival differed among species, with higher rates for P. grandis compared to A. muricata, indicating no impact due to stocking methods but species‐specific differences. Challenges like nursery collapses and amphipod outbreaks may have impacted survival, emphasizing the importance of consistent maintenance and accessibility of project sites. Furthermore, the fishing line method reduced cleaning effort. However, cost considerations and preparation complexities for fishing line warrant careful evaluation, particularly with regards to project budgets. The study underscores the necessity for further research, incorporating diverse genotypes, species, and initial fragment sizes to refine restoration strategies. In summary, this study provides important guidance for coral restoration practitioners, aiding informed decisions on stocking methods for different projects and species while considering the balance between coral health benefits and operational feasibility.

Assessment of Octocoral‐Dominated Benthic Assemblages Along a Mesophotic Gradient, With a Focus on the Impact of Lost Fishing Gears

ABSTRACTCoralligenous, a typical Mediterranean mesophotic habitat, is a highly diverse assemblage, severely threatened by several stressors, including fishing litter. To characterise the coralligenous of the upper mesophotic of the Portofino Promontory (Ligurian Sea, Italy), video transects at 35 and 50 m depth were performed at four sites. Benthic assemblages and lost fishing gears were recorded, and the two depths compared. A higher coverage of taxa with complex 3D structures was found at 50 m, mainly due to the gorgonian Paramuricea clavata. However, the overall low density of this species (0.4–6.6 colonies/m2), together with the impact caused by 120 fishing lines found along the transects, highlights the need for tailored conservation measures. With climate change moving further down the water column and fishing impacts being a major cause of degradation, the design of marine protected areas needs to be extended to include mesophotic depths, contributing to the 30 × 30 targets agreed upon at the COP15.

Evaluation of genetic consequences of stocking on the southern-margin populations of white-spotted charr.

Coldwater-adapted freshwater fishes, especially their populations along warm-range margins, are most vulnerable to the climate oscillations associated with global warming. Stocking is a major strategy for avoiding the extinction of these species. However, while stocking can reverse the decline of isolated populations, it may also result in a loss of genetic diversity in the native local population due to the introgressive replacement of hatchery genes. To plan an adequate strategy for conserving locally adapted populations, the genetic impacts of stocking on native lineages should be evaluated from small river branches to wide-ranging drainage areas. We investigated the population genetic structure of white-spotted charr (Salvelinus leucomaenis) within its southern range (Lake Biwa basin, Japan). By applying genome-wide SNP analysis to the population's genetic structure, we assessed the extent of genetic introgression resulting from stocking. White-spotted charr in the Lake Biwa watershed constitutes a distinctive genetic group, within which apparent genetic differentiation was observed. The hatchery-reared fish line commonly used for supplementation stocking in the catchment was discernable from the native population, enabling us to analyze genetic introgression across the entire drainage area. Admixed individuals resulting from hatchery introgression were observed in most of the stocked sites that showed relatively high heterozygosity and nucleotide diversity. However, their genetic differentiation was much lower than that of native populations. The supplementation history as well as the road availability contributed substantially to the introgression of hatchery genes. Populations with the native genetic structure remained in the upstream regions of the tested rivers. However, their heterozygosity and nucleotide diversity were low when compared with that of the populations with hatchery supplementation. Our results shed light on the genetic impacts of stocking on isolated native populations and suggest that conventional supplementation methods cannot preserve a unique biodiversity in the distribution margin.

Aging suppression in Multistrip Multigap Resistive Plate Chambers for high counting rate experiments

A long term operation of Multi-Strip Multi-Gap Resistive Plate Chambers (MSMGRPC) with gas mixtures based on C2H2F4 and SF6 leads to aging effects observed as depositions on the surface of the resistive electrodes, especially in the region of the spacers used for defining the gas gaps between the resistive electrodes. The observed higher noise rate and dark current has a negative impact on the performance of the chamber and leads to an increase of the data volume in a free running readout mode operation. MSMGRPC prototypes designed with a direct gas flow through the gas gaps and minimization of the number of spacers in the active area were developed as mitigation solution. Three new prototypes of different granularities were assembled using fishing line as spacers and investigated for aging effects. Although a significant reduction in the dark current and dark counting rate was evidenced, noise rate localized around the fishing line spacers, even though reduced, still remains. In this paper, a new generation of direct flow chambers based on discrete spacers is presented. The results of their aging investigations show that, even at lower gas flows, the aging effects become negligible.

Interaction between coastal birds and recreational fisheries in Argentine: Incorporating the social dimension to improve effectiveness of conservation and management measures in a key estuarine reserve

Marine recreational fishing in Argentina is an activity with a high socioeconomic impact. Its effects on the ecosystem have been poorly explored, for example, impacts of anglers on coastal birds. This study assessed perceptions and feelings of anglers towards their interaction with coastal birds, with the ultimate goal of generating information of socioecological value to be incorporated into national conservation instruments. A total of 240 structured questionnaires were conducted on active recreational fishers from the Mar Chiquita Reserve, Argentina. Main motivations to visit the fishing site expressed by respondents were the fishing quality and the peaceful and natural features of the reserve. Most anglers knew about the protected status of the site and have seen coastal birds during their fishing day, considering them to be beneficial to the ecosystem. Anglers observed coastal birds feeding on discards frequently; birds stealing the bait or the catch at moderate frequency; and birds entangled in fishing lines rarely. Most anglers indicated the occurrence of interaction with coastal birds during their activities, and expressed sadness when spotting a bird entangled in a fishing line. The information that emerged from this study could be used to develop informational strategies, for example guidelines for responsible fishing and signage aimed to inform anglers about the potential impacts of their interaction with coastal birds.

Tuning apicobasal polarity and junctional recycling in the hemogenic endothelium orchestrates the morphodynamic complexity of emerging pre-hematopoietic stem cells

Hematopoietic stem cells emerge in the embryo from an aortic-derived tissue called the hemogenic endothelium (HE). The HE appears to give birth to cells of different nature and fate but the molecular principles underlying this complexity are largely unknown. Here we show, in the zebrafish embryo, that two cell types emerge from the aortic floor with radically different morphodynamics. With the support of live imaging, we bring evidence suggesting that the mechanics underlying the two emergence types rely, or not, on apicobasal polarity establishment. While the first type is characterized by reinforcement of apicobasal polarity and maintenance of the apical/luminal membrane until release, the second type emerges via a dynamic process reminiscent of trans-endothelial migration. Interfering with Runx1 function suggests that the balance between the two emergence types depends on tuning apicobasal polarity at the level of the HE. In support of this and unexpectedly, we show that Pard3ba – one of the four Pard3 proteins expressed in the zebrafish – is sensitive to interference with Runx1 activity, in aortic endothelial cells. This supports the idea of a signaling cross talk controlling cell polarity and its associated features, between aortic and hemogenic cells. In addition, using new transgenic fish lines that express Junctional Adhesion Molecules and functional interference, we bring evidence for the essential role of ArhGEF11/PDZ-RhoGEF in controlling the HE-endothelial cell dynamic interface, including cell-cell intercalation, which is ultimately required for emergence completion. Overall, we highlight critical cellular and dynamic events of the endothelial-to-hematopoietic transition that support emergence complexity, with a potential impact on cell fate.

Tuning apicobasal polarity and junctional recycling in the hemogenic endothelium orchestrates the morphodynamic complexity of emerging pre-hematopoietic stem cells.

Hematopoietic stem cells emerge in the embryo from an aortic-derived tissue called the hemogenic endothelium (HE). The HE appears to give birth to cells of different nature and fate but the molecular principles underlying this complexity are largely unknown. Here we show, in the zebrafish embryo, that two cell types emerge from the aortic floor with radically different morphodynamics. With the support of live imaging, we bring evidence suggesting that the mechanics underlying the two emergence types rely, or not, on apicobasal polarity establishment. While the first type is characterized by reinforcement of apicobasal polarity and maintenance of the apical/luminal membrane until release, the second type emerges via a dynamic process reminiscent of trans-endothelial migration. Interfering with Runx1 function suggests that the balance between the two emergence types depends on tuning apicobasal polarity at the level of the HE. In support of this and unexpectedly, we show that Pard3ba - one of the four Pard3 proteins expressed in the zebrafish - is sensitive to interference with Runx1 activity, in aortic endothelial cells. This supports the idea of a signaling cross talk controlling cell polarity and its associated features, between aortic and hemogenic cells. In addition, using new transgenic fish lines that express Junctional Adhesion Molecules and functional interference, we bring evidence for the essential role of ArhGEF11/PDZ-RhoGEF in controlling the HE-endothelial cell dynamic interface, including cell-cell intercalation, which is ultimately required for emergence completion. Overall, we highlight critical cellular and dynamic events of the endothelial-to-hematopoietic transition that support emergence complexity, with a potential impact on cell fate.

Isavuconazole Induces Neurodevelopment Defects and Motor Behaviour Impairment in Zebrafish Larvae.

Isavuconazole is a broad-spectrum antifungal drug used for the treatment of serious infections caused by invasive aspergillosis and mucormycosis in adults. With the continuous use of this drug, its safety and environmental impact have received increasing attention. However, information on the adverse effects of the drug is very limited. Fish is a particularly important model for assessing environmental risks. In this study, the aquatic vertebrate zebrafish was used as a model to study the toxic effects and mechanisms of isavuconazole. We exposed zebrafish embryos to 0.25, 0.5, and 1mg/L of isavuconazole 6h after fertilization. The results showed that at 72 hpf, isavuconazole exposure reduced heart rate, body length, and survival of zebrafish embryos compared to controls. Secondly, when isavuconazole reached a certain dose level (0.25mg/L), it caused morphological changes in the Tg(elavl3:eGFP) transgenic fish line, with the head shrunk, the body bent, the fluorescence intensity becoming weaker, the abnormal motor behaviour, etc. At the same time, exposure of zebrafish embryos to isavuconazole downregulated acetylcholinesterase (AchE) and adenosine triphosphate (ATPase) activities but upregulated oxidative stress, thereby disrupting neural development and gene expression of neurotransmitter pathways. In addition, astaxanthin partially rescued the neurodevelopmental defects of zebrafish embryos by downregulating oxidative stress. Thus, our study suggests that isavuconazole exposure may induce neurodevelopment defects and behavioural disturbances in larval zebrafish.

Tuna: Investigations of value addition and potential EU investments in tuna fisheries in Africa

This research studies investment opportunities within the tuna fish pole and line fishery by the coast of the African Atlantic Façade (mainly SW–Senegal), and the associated value chains. Also, a section is dedicated to investigating the specific case of investment of French capital in tuna fisheries in Seychelles in the Indian Ocean. The investigation was conducted under the FarFish project, which overarching objective is to provide knowledge, tools and methods to support responsible, sustainable and profitable EU fisheries outside European waters, both within the jurisdiction (EEZ) of non-EU coastal states as well as in international waters/high seas. In order to achieve this, the aim of this research is to identify, study and potentially recommend investment opportunities for EU operators within some of the project’s case study countries. The investigations done into tuna fisheries were based on interviews with relevant stakeholders, including shipowners and key personnel from public bodies and institutions both in West Africa and Europe (see Appendix A for the list of stakeholders consulted). In addition, most of the data presented in this section was acquired from DG-Mare in a non-public dataset compiling every fishing lot from EU vessels operating within SFPAs in Senegal. A second case study in tuna fisheries in this case in the Indian Ocean, investigates the investment from the French company SAPMER to improve the land infrastructure in the Port of Victoria (Seychelles), as this would be the only notable investment by European interests in recent years for tuna fishing in Africa. These sections conclude that the fishing area where EU pole-and-line vessels are active is becoming less productive, decreasing the profitability of European flagged vessels, as well as of Senegalese flagged vessels that maintain close partnerships with Europe. As a response, they have attempted to extend their fishing grounds. Additional fishing opportunities are opening in The Gambia (whose EEZ is restricted) and other countries are expected to follow. Contrastingly, the EU sustainable partnership fisheries agreement with Senegal or Mauritania could include fewer fishing opportunities in terms of tonnage, as well as increasingly restrictive conditions for access and landings. European operators have reacted so far by considering the switch to private regime, instead of operating under SFPA, as a preferred strategy.

Seasonal and Spatial Distribution Characteristics of Sepia esculenta in the East China Sea Region: Transfer of the Central Distribution from 29° N to 28° N.

The golden cuttlefish (Sepia esculenta) is an important cephalopod species with a lifespan of approximately one year. The species plays a crucial role in marine ecological support services and is commercially valuable in fisheries. In the seas around China, this species has emerged as the main target for cuttlefish fisheries, replacing Sepiella maindroni since the 1990s. Variations in oceanographic conditions associated with global warming could significantly impact the temporal-spatial distribution of the species. In this study, we performed bottom trawling surveys with four cruises during 2018-2019 in the East China Sea region to determine the current resource status and seasonal-spatial variations in S. esculenta. We found that the average individual weight (AIW) values were 4.87 and 519.00 g/ind at stations located at 30.50° N, 124.00° E and 30.50° N, 124.50° E, respectively, with the aggregation of larvae and parent groups in spring. The species was not distributed north of 32.00° N in summer. The catch per unit effort by weight (CPUEw) value decreased in the order of 2772.50→2575.20→503.29→124.36 g/h, corresponding to latitudes of 34.50° N→34.00° N→33.50° N→32.50° N 121.50° E in autumn. The most suitable fishing areas were the south of the East China Sea region in spring; the south of the East China Sea region extending to the center and outer parts of the East China Sea region in summer; the south of the Yellow Sea close to the Haizhou Bay fishing ground and the forbidden fishing line region of the Lusi and Dasha fishing grounds in autumn; and the south and center of the East China Sea region in winter. The most suitable sea bottom temperature (SBT) values from spring to winter were 14.76-20.53 °C, 19.54-22.98 °C, 11.79-17.64 °C, and 16.94-20.36 °C, respectively. The most suitable sea bottom salinity (SBS) values were 31.53-34.80‱ in spring, 32.95-34.68‱ in summer, 31.51-34.77‱ in autumn, and 33.82-34.51‱ in winter. We concluded the following: (1) the southern and northern areas of the East China Sea region are spawning and nursery grounds, respectively, in spring; (2) the central distribution is located at a latitude of 28.00° N in autumn and winter; and (3) the southern area of the Yangtze River to the north is a spawning ground in spring, and the areas located at 29.00-34.50° N, 124.00-124.50° E, and 28.00-30.50° N, 125.50-126.50° E are nursery grounds. The results of this study provide useful guidance for appropriate fisheries management, thereby avoiding a collapse in the S. esculenta population, which has been experienced in other species in this area.

Catch composition of fishes by different types of fishing gears in the Andaman sea, Thailand

The Andaman Sea is a rich ecosystem providing significant ecosystem goods and services for people in coastal areas and these areas have fisheries activities using different fishing gears appropriate for different species and habitats. We assessed catch composition and size distribution of economically important finfish captured by a range of fishing gears employed by commercial and artisanal fishers in three provinces adjacent to the central Andaman Sea of Thailand over a 2-year period. Between January 2019 and December 2021, fishers employed 7 main capture gears: surface gillnet, bottom gillnet, fish trap, handline and hook, trawl, purse seines and light-luring anchovy falling net. Trawling captured the highest diversity of target species (35 species) followed by surrounding net (32 species), fish trap (16 species) hook and line (15 species), surface and bottom gillnet (15 species) and the last one of anchovy falling net (2 species). When comparing size at the first maturation of both target species and bycatch, it was found that the percentage of mature fish caught from artisanal fishing gears was higher than of commercial fishing gear because artisanal gears had better selection of catch, especially fish trap and hook and line. Understanding the operation of fishing gears, catch composition and the size frequencies of target species could be particularly important for stock assessment because gear may influence catch composition.

Impact of marine debris on coral reef ecosystem of Palk Bay, Indian Ocean

Abstract Coral reef ecosystems are highly sensitive to pollution from marine debris, especially if the regions are noted for tourism and fishing. Palk Bay on the south east coast of India is a famous tourist and fishing region, where the marine debris accumulation poses a great threat to the coastal ecosystem. In this study during 2018–2020, the marine debris distribution and their interactions with coral reefs of Palk Bay were monitored from five stations. Derelict fishing gears (DFGs), including ropes (51 ± 2%) and fishing lines (43 ± 2.5%), were the dominant debris forms recorded. Among the reef‐forming corals, Acropora sp. colonies experienced maximum physical injury and mortality from DFG entanglement. Plastic materials and anchors caused considerable physical damage and tissue loss in Porites sp, without any mortality. Manual debris removal as a potential debris management method was assessed by regularly removing the accumulated debris from the test reef locations of all five stations, whereas the control reef locations were left undisturbed. Test reef locations showed a significant increase in live coral cover and coral recruit density in 2020, against that in 2018, compared with the control locations. Continuous accumulation and interaction of marine debris with the coral colonies of control reef locations resulted in significant reduction of live coral cover and coral recruit density at the control reef locations. This study illustrates the impact of unsustainable fishing and other anthropogenic activities such as tourism and waste disposal on coral reef ecosystems like Palk Bay. The findings of this study demonstrates that manual removal of debris is an important strategy for marine debris management in coral reef ecosystem. Considering the importance of coral reefs in the livelihood of the coastal communities, it is important to tackle the marine debris issue through regular debris removal with stakeholder participation, awareness campaigns and strict legal and management measures.

COMPARISON OF MECHANICAL PROPERTIES OF WOVEN HYBRID METALLIC FABRICS WITH DIFFERENT ARRANGEMENT OF INTERMEDIATE ALUMINUM SHEETS

In this study, hybrid metallic fabrics were produced by traditional weaving method using 0.2 mm thick Aluminum (Al) 1005 H14 material and polyethylene fishing line (PL). During the production of hybrid metallic fabrics, fishing line was used as warp and Al 1005 H14 wire of the same thickness was used as weft. The fabrics were cut into layers with dimensions of 30 mm width and 300 mm length. Each layer was bonded using FM® 73M structural adhesive. Laminates of hybrid composites with different arrangement of layers were fabricated with Al 5005 H34 spacer sheet. The resulting laminates were cured by applying additional pressure in a temperature-controlled hydraulic press, after which the specimens were cut for tensile testing with a saw according to ASTM D3039 standard. The effect of the Al 5005 H34 intermediate material on weight was determined. Three specimens from each laminate group were tensile tested and the results analyzed. It was found that fabrics containing Al 1005 H14 and PL can be successful.

Characterization of a novel fast-growing zebrafish: a new approach to growth hormone transgenesis.

The manipulation of the somatotropic axis, governing growth, has been a focus of numerous transgenic approaches aimed at developing fast-growing fish for research, medicine and aquaculture purposes. However, the excessively high growth hormone (GH) levels in these transgenic fish often result in deformities that impact both fish health and consumer acceptance. In an effort to mitigate these issues and synchronize exogenous GH expression with reproductive processes, we employed a novel transgenic construct driven by a tilapia luteinizing hormone (LH) promoter. This approach was anticipated to induce more localized and lower exogenous GH secretion. In this study, we characterized the growth and reproduction of these transgenic LHp-GH zebrafish using hormonal and physiological parameters. Our findings reveal that LHp-GH fish exhibited accelerated growth in both length and weight, along with a lower feed conversion ratio, indicating more efficient feed utilization, all while maintaining unchanged body proportions. These fish demonstrated higher expression levels of LH and GH in the pituitary and elevated IGF-1 levels in the liver compared to wild-type fish. An examination of reproductive function in LHp-GH fish unveiled lower pituitary LH and FSH contents, smaller follicle diameter in female gonads, and reduced relative fecundity. However, in transgenic males, neither the distribution of spermatogenesis stages nor sperm concentrations differed significantly between the fish lines. These results suggest that coupling exogenous GH expression with endogenous LH expression in females directs resource investment toward somatic growth at the expense of reproductive processes. Consequently, we conclude that incorporating GH under the LH promoter represents a suitable construct for the genetic engineering of commercial fish species, providing accelerated growth while preserving body proportions.

Estuary Clean Up dalam Mendukung Pengelolaan Kawasan Pesisir Desa Sungai Nibung Kalimantan Barat

Desa Sungai Nibung is a coastal with high biodiversity, so this village has been designated as a conservation area in West Kalimantan with the main conservation target is mangrove. The mangrove ecosystem has an important ecological role, namely as a habitat for marine and coastal biota. A maintained ecosystem will protect the survival of the biota within it. Therefore, managing coastal areas is essential and a shared responsibility. One of the challenges faced in the management process in Desa Sungai Nibung is plastic waste pollution. This waste comes from disposal and runoff from land, which can enter rivers and the sea. Plastic pollution also comes from fishing activities, such as ship traffic, responsive fisheries, and cultivation. This waste needs to be appropriately managed because there is no final waste disposal site (TPA). Household waste and waste from several shops (plastic food and drink packaging) are dumped directly around the building. The accumulation of plastic waste will continue to increase. Therefore, cleanup activities were carried out to reduce plastic waste. Apart from that, this activity aims to educate activity participants about the negative impact of plastic waste on the environment. This community service activity was carried out by a lecturer in Marine Science, FMIPA, Tanjungpura University, who involved students from the Merdeka Belajar Kampus Merdeka (MBKM) program. Beaches and coastal clean-up from macroplastic waste are carried out in residential areas, docks, and areas near fishing activities and ecotourism areas. Implementation of PKM activities consists of permission and coordination, implementation, monitoring, and evaluation. The waste from activities varies from plastic bags, sachet packaging, and food containers to fishing lines. Plastic waste dominates compared to other waste. Participants' understanding concerning plastic waste pollution and its negative impact on the environment and aquatic organisms increased after the activity took place.

Single layered soft skin actuated with twisted and mandrel coiled actuators for soft robotics

AbstractSoft silicone‐based artificial skin is essential in soft robotics because of high elongation, safe human interaction, low energy requirements and ease of manufacturing. Inspired by nature, several attempts have been made to fabricate morphing structures using synthetic soft skin. In this study, a novel elastomeric skin is demonstrated featuring embedded actuators and micro‐fluidic channels, that is capable of grasping objects. The actuators are twisted, and mandrel coiled nylon artificial muscles, with nichrome heaters that overcome key challenges in developing synthetic soft skin. The desired properties of a morphing skin are being low‐cost, lightweight, highly deformable, compact size, silent cyclic actuation, fast response, and long life. The actuators are fabricated from 160 μm diameter resistance wires wrapped on twisted nylon 6 fishing line precursor fibers of 800 μm diameter. The wrapped nichrome (0.42 mm pitch) along with the twisted precursor fibers are coiled on a 1.4 mm diameter mandrel rod to obtain high strain. This muscle termed twisted, and mandrel coiled polymer fishing line muscle with nichrome is embedded in soft skin samples and tested. Characterization results on the actuators (3.2 mm in diameter) showed remarkable tensile actuation of ~36% strain from loaded length at 0.99 MPa for an input power of 4.9 W, a blocked stress of 1.27 MPa, an actuation frequency of 0.04 Hz, and a lifecycle >22,000 cycles. These actuators, when embedded in the soft skin of 4 mm thick, showed ~50% bending strain within 10s and a cyclic behavior with active water cooling. A soft gripper fabricated with embedded soft skin is integrated to our child‐sized humanoid robot (HBS Robot) demonstrating its potential in grasping unconventional and deformable objects, hence advancing the progress in soft robotics.