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The rapid advancement of 3D bioprinting has created a need for cost-effective and versatile 3D printers capable of handling bio-inks at various scales. This study introduces a novel framework for a specialized nozzle-holding device designed for an extrusion-based 3D bioprinter, specifically tailored to address the rigorous requirements of tissue engineering applications. The proposed system combines a pneumatically actuated plunger mechanism with an adaptive nozzle system, ensuring the safe inhibition and precise dispensing of bio-inks. Rigorous thermal management strategies are employed to maintain consistently low temperatures, thereby preserving bio-ink integrity without changing chemical stability. A key component of this design is a precision-milled aluminum block, which optimizes thermal characteristics while providing a protective barrier. Additionally, a 3D-printed extruder head bracket, fabricated using a high-precision resin printer, effectively mitigates potential thermal inconsistencies. The integration of these meticulously engineered components results in a modified extrusion-based 3D bioprinter with the potential to significantly advance tissue engineering methodologies. This study not only contributes to the advancement of bioprinting technology but also underscores the crucial role of innovative engineering in addressing tissue engineering challenges. The proposed bioprinter design lays a solid foundation for future research, aiming to develop more accurate, efficient, and reliable bioprinting solutions. [ABSTRACT FROM AUTHOR]

Sustainable hybrid composites, made of two different natural plant fiber types, are increasingly being attracted by composite researchers, for their cost effectiveness and ability to control mechanical performances through varying weight ratios of different fibers. In contrast, their lower mechanical properties are reported in the literature, because of strength variations of different fiber types and an improper fiber‐matrix stress distribution. Therefore, it is aimed to develop sustainable hybrid composites from two dry fiber preforms—woven fabric and short fiber preform—originated from same fiber type (jute). A highly packed short fiber preform is used as the core layer, while woven fabrics (plain/twill–rib/twill–diamond) are used in the skin layers for producing sandwiched hybrid jute composites. Mechanical tests and scanning electron microscopy images show that hybridized plain fabric/short fiber preform composites have better mechanical properties (≈58 MPa tensile strength/≈117 MPa flexural strength/≈112.12 kJm−2 impact strength with an ≈487.4% improvement) compared to other fabric structures hybrid/nonhybrid composites. This enhancement is related to the interlocking of short fibers with long plain fabric leading to a strong fiber‐matrix interfacial bonding. Thus, this developed hybrid composites, can be applied in many semi‐structural applications, wherein composites’ low cost and mechanical performances are primary concerns. [ABSTRACT FROM AUTHOR]

Groupers are among the fish groups that are difficult to recognize due to their high morphological similarities. Therefore, molecular techniques, particularly DNA barcoding, are extensively utilized to differentiate this fish group. This study aimed to analyze and validate six grouper species belonging to the Epinephelidae family that were harvested from Langsa district waters in Aceh province, Indonesia, based on DNA barcode data. It was conducted from June to December 2021, with the fish specimens collected from fishers at fish landing sites and the fish market in Langsa City, Aceh province. A total of 22 grouper sequences belonging to six species were generated, namely Epinephelus coioides, E. bleekeri, E. malabaricus, E. erythrurus, E. sexfasciatus and Mycteroperca poecilonotus (formerly Epinephelus poecilonotus). Genetic distance within these species ranged from 0.10 to 0.73% (average: 0.40%). Notably, E. malabaricus and E. coioides exhibited the closest genetic kinship (4.07%), while E. sexfasciatus and M. poecilonotus displayed the greatest genetic distance (19.33%). This study provides the first DNA reference for grouper in Langsa district, Indonesia, with significant implications for future sustainable grouper management. [ABSTRACT FROM AUTHOR]

Three Dimensional (3D) bioprinting holds great promise for tissue and organ regeneration due to its inherent capability to deposit biocompatible materials containing live cells in precise locations. Extrusion-based 3D bioprinting (EBP) method stands out for its ability to achieve a higher cell release rate, ensuring both external and internal scaffold structures. The systematic adjustment of key process parameters of EBP, including nozzle diameter, printing speed, print distance, extrusion pressure, material fraction, and viscosity allows for precise control over filament dimensions, ultimately shaping the desired scaffold porosity as per user specifications. However, managing these factors with all possible interactions simultaneously to achieve the desired filament width can be intricate and resource intensive. This study presents a novel framework designed to construct a predictive model for the filament width of 3D bioprinted scaffolds for various process parameters. A total of 157 experiments have been conducted under various combinations of process parameters and biomaterial's weight fraction for this study purpose. A regression-based machine learning approach is employed to develop the predictive model utilizing Adj. R², Mallow's Cp, and Bayesian Information Criterion (BIC). Following model development, rigorous experimental validations are conducted to assess the accuracy and reliability of the model. Based on the cross-validation of randomly split test data, Adj. R² model emerges as the highest performing machine learning model (Mean Squared Error, MSE = 0.0816) compared to Mallow's Cp and BIC (MSE = 0.0841 and 0.0877, respectively) models. The comparative analysis results between the experimental and model's data demonstrate that our predictive model achieves an accuracy of approximately 85% in filament width prediction. This framework presents a significant advancement in the precise control and optimization of 3D bioprinted scaffold fabrication, offering valuable insights for the advancement of tissue engineering and regenerative medicine applications. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is a versatile polymer with numerous applications that has undergone substantial changes in recent years, focusing on the demand for next-generation polymers. This article provides a comprehensive review of recent research in PP and its advanced functional applications. The chronological development and fundamentals of PP are mentioned. Notably, the incorporation of nanomaterial like graphene, MXene, nano-clay, borophane, silver nanoparticles, etc., with PP for advanced applications has been tabulated with their key features and challenges. The article also conducts a detailed analysis of advancements and research gaps within three key forms of PP: fiber, membrane, and matrix. The versatile applications of PP across sectors like biomedical, automotive, aerospace, and air/water filtration are highlighted. However, challenges such as limited UV resistance, bonding issues, and flammability are noted. The study emphasizes the promising potential of PP while addressing unresolved concerns, with the goal of guiding future research and promoting innovation in polymer applications. [ABSTRACT FROM AUTHOR]

Heavy metals are a crucial group of chemicals extensively used in materials to meet human needs, eventually leading to contamination of aquatic ecosystems and accumulation in organism's tissues. Heavy metals enter the aquatic ecosystem from various sources. Those metals that pollute aquatic waters are deposited in sediments, remain dissolved in water or accumulate in the food web of aquatic organisms. Benthic biota is believed to accumulate the highest levels of these metals, while other aquatic animals, such as fish, shrimp, and macroalgae, serve as significant sources of heavy metals intake through food and the environmental exposure. Ina study conducted in and around the east Java, Indonesia, the concentration of heavy metals in commercially important fish species, shellfish, and macroalgae were evaluated using an inductive couple plasma-mass spectrometer (ICP-MS). This study is very important because fishery resources are not only vital for exports but also serve as a primary source of essential food for local communities. The results showed that heavy metal concentration (Pb, Cd, and Hg) in samples were 12.3 mg·dm-3, 0.171 mg·dm-3, and undetectable, respectively. This study showed that different metals were present in the samples at different levels, all of which fell within the maximum residual levels set by the EU and USFDA. The results of an analysis of food safety based on the Hazard Index showed values below 1 point, indicating that fishery products (fish, shrimp, and macroalgae) from the East Java Province are generally safe for human consumption. [ABSTRACT FROM AUTHOR]

This editorial discusses the impact of climate change on aquatic organisms, focusing on their ecology, diversity, and migration patterns. The Intergovernmental Panel on Climate Change (IPCC) reports that climate change is a significant threat to global biodiversity, and aquatic species are expected to shift their habitats in response to climate changes. The rise in temperature negatively affects marine species' performance and survival, and climate change also has unpredictable impacts on freshwater resources. The editorial highlights the importance of understanding these impacts and provides insights into specific topics such as siphonophores, odour-producing microorganisms, and the vulnerability of coral reefs. The authors emphasize the need for further research and conservation efforts to mitigate the effects of climate change on aquatic ecosystems. [Extracted from the article]

Aquaculture is growing rapidly as a food-producing sector and in recent years fishmeal prices have climbed more than two-fold on a global scale. This review of previous studies was performed to contribute to the extant literature on the aquaculture sector to aid cost reduction of aquafeeds by identifying substitute proteins that can replace fishmeal. The review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) using the SCOPUS and WOS (Web of Science), DOAJ (Directory of Open Access Journals), Academia, and PubMed Central databases. A total of 59 articles were included in the synthesis after screening for duplicates and articles that did not conform to the criteria. Results have shown that the 100% replacement of fishmeal with blood meal (BM) did not affect the growth of fish, nor did the 75% to 100% combination of poultry-by-product (PBM), feather meal (FEM), and BM. Moreover, a 10% replacement of fishmeal using seaweed (Gracilaria arcuata) had no adverse effect on the feed efficiency and growth performance of tilapia. Similarly, a 50% replacement of fishmeal using black soldier fly (Hermetia illucens), and a 25% replacement using soybean (Glycine max) also showed better results for fish growth. Our review shows that alternative protein can replace fishmeal in the aquaculture sector and reduce the cost of aquafeeds since alternative proteins are much cheaper than the usual fishmeal. Adoption of these alternative protein sources hinges on financial support, start-up incentives for companies, and ongoing studies on waste-to-feed production, which the government can also support. [ABSTRACT FROM AUTHOR]

Water quality is important in natural environments for an organism to sustain optimum physical conditions, as poor physicochemical characteristics can result in poor production and economic losses. The present study sets out to determine the subcritical of minimum and maximum physicochemical water parameters (pH, temperature, and dissolved oxygen) tolerance limit for the giant freshwater prawn, Macrobrachium rosenbergii. To explore this, samples of 48 juvenile prawns (2.70 ± 0.27 g) were randomly subject to 6 replicates. The trials on dissolved oxygen were conducted by reducing dissolved oxygen levels in water over 12 h duration, pH test was conducted by lowering the pH level by adding 5% hydrochloride acid over 2 h. A temperature test was conducted by increasing the temperature with the water heater over 4 h, and ice was added to reduce the water temperature over 3 h. The critical point of dissolved oxygen was observed at 2.9 to 1.9 mg O2 L–1 before M. rosenbergii displayed signs of stress until fatality occurred at 0.5 mg O2 L–1. The subcritical point range of pH was recorded between 2.6 (min) and 4.6 (max). The critical tolerance cold shock temperature limit for M. rosenbergii was observed at a range of 16.8 °C to 23.2 °C. M. rosenbergii showed stress signs between 32.9 °C and 36.7 °C. The results provide critical information on the subcritical tolerance levels of each water parameter, including dissolved oxygen, temperature and pH for giant freshwater prawns, which could prevent massive mortality due to changes in physicochemical water parameters. [ABSTRACT FROM AUTHOR]

The present study offers the first report of length-weight relationships (LWRs) and relative condition factor (Kn) of coralassociated snapper fishes namely: Lutjanus johnii, L. quinquelineatus, and L. xanthopinnis collected from Pulau Kambing fish landing port, Terengganu waters of South China Sea, Malaysia. This study also offers a new maximum total length of 26.8 cm (standard length of 21.3 cm) for L. xanthopinnis. A total of 861 specimens were collected monthly from March 2022 to February 2023 that were caught by using different types of fishing gear such as gill nets (mesh size 45-48 mm), hooks (numbers 9-12), and trawl nets (cod end mesh size 38 mm). In LWRs the growth coefficient b value was calculated at 2.602, 2.962, and 3.051, and the coefficient of determination r² value 0.948, 0.906, and 0.961 for L. johnii, L. xanthopinnis, and L. quinquelineatus, respectively. The student's t-test showed L. johnii had a negative allometric growth pattern. On the other hand, L. quinquelineatus and L. xanthopinnis showed an isometric growth pattern. The Kn values for L. johnii, L. quinquelineatus, and L. xanthopinnis were 1.005, 1.030, and 1.024 which indicates they are in a state of healthy growth. LWRs data for three Lutjanus species from the Malaysian South China Sea can be used for fisheries research and management of stocks. [ABSTRACT FROM AUTHOR]

The long‐term future of information storage requires the use of sustainable nanomaterials in architectures operating at high frequencies. Interfaces can play a key role in this pursuit via emergent functionalities that break out from conventional operation methods. Here, spin‐filtering effects and photocurrents are combined at metal‐molecular‐oxide junctions in a hybrid magneto‐capacitive memory. Light exposure of metal‐fullerene‐metal oxide devices results in spin‐polarized charge trapping and the formation of a magnetic interface. Because the magnetism is generated by a photocurrent, the writing time is determined by exciton formation and splitting, electron hopping, and spin‐dependent trapping. Transient absorption spectroscopy measurements show changes in the electronic states as a function of the magnetic history of the device within picoseconds of the optical pumping. The stored information is read using time‐resolved scanning magneto optic Kerr effect measurements during microwave irradiation. The emergence of a magnetic interface in the picosecond timescale opens new paths of research to design hybrid magneto‐optic structures operating at high frequencies for sensing, computing, and information storage. [ABSTRACT FROM AUTHOR]

Among various available 3D bioprinting techniques, extrusion-based three-dimensional (3D) bioprinting allows the deposition of cell-laden bioink, ensuring predefined scaffold architecture that may offer living tissue regeneration. With a combination of unique characteristics such as biocompatibility, less cell toxicity, and high water content, natural hydrogels are a great candidate for bioink formulation for the extrusion-based 3D bioprinting process. However, due to its low mechanical integrity, hydrogel faces a common challenge in maintaining structural integrity. To tackle this challenge, the rheological properties, specifically the shear thinning behavior (reduction of viscosity with increasing the applied load/shear rate on hydrogels) of a set of hybrid hydrogels composed of cellulose-derived nanofiber (TEMPO-mediated nano-fibrillated cellulose, TO-NFC), carboxymethyl cellulose (CMC), and commonly used alginate, were explored. A total of 46 compositions were prepared using higher (0.5% and 1.0%) and lower percentages (0.005% and 0.01%) of TO-NFC, 1–4% of CMC, and 1–4% of alginate to analyze the shear thinning factors such as the values of n and K, which were determined for each composition from the flow diagram and co-related with the 3D printability. The ability to tune shear thinning factors with various ratios of a nanofiber can help achieve a 3D bio-printed scaffold with defined scaffold architecture. [ABSTRACT FROM AUTHOR]

Snapper is a type of demersal marine fish from the Lutjanidae family. The Lutjanidae family spread throughout the world and currently has 123 species in 21 genera, one of which is the Lutjanus genus (Miller and Thomas, 2007). To this day, the records of capture fisheries production data for snapper in Malang are still very limited to certain types. Morphological identification that has been carried out so far is still challenging to obtain accurate results because of the many similarities between the observed species or the loss of characteristics. Therefore, molecular identification is necessary to determine the types of snappers in this area and their conservation status. This study aims to determine the types of snappers using a molecular approach by Cytochrome Oxidase subunit I (COI) gene marker. Phylogenetic tree reconstruction and genetic distance calculations were performed using Mega X software through the neighbour-joining (NJ) algorithm. The results of the identification snapper based on a molecular approach with DNA barcoding revealed that the four snapper samples were L. gibbus, L. rufolineatus, L. bengalensis, and L. erythropterus. Based on the results of the compilation of the phylogenetic tree, it can be seen that the L. bengalensis sample is closely related to L. rufolineatus while L. gibbus, and L. erythropterus each form a separate clade from the two previous Lutjanus species. Based on their conservation status at the IUCN, the four species of snapper found are in the Least Concern category. [ABSTRACT FROM AUTHOR]

River water and sediment embody environmental characteristics that give valuable information about the eco-environment. Due to rapid unplanned urbanization and industrialization, the aquatic environment of any urban river can be seriously polluted by heavy metals. Four heavy metals (As, Cr, Cd, and Pb) were analyzed in surface sediments and water from the Kirtankhola River located in the coastal area of Bangladesh. The decreasing pattern of metals was observed as Cr > Pb > As > Cd in both water and sediment. The heavy metal ranges were 1.67–7.31, 12.64–45.69, 0.01–1.59, and 8.03–35.68 μg/L in the water and 2.09–6.89, 14.76–47.08, 0.01–1.77 and 6.37–41.43 mg/kg in sediments for As, Cr, Cd, and Pb. The number of metals tested in water samples surpassed the acceptable limits of drinking water quality, indicating that water from this river is not safe for drinking and cooking and could pose a risk to the riverine ecosystem. The pollution load index (PLI) values were close to one, indicating that the sediment of the study river was low contamination. Contamination factor (CF) has reported that As, Cd, and Pb have been moderate to extremely polluted by sediment samples and metals level implied that the condition is much alarming and probably severely affecting the aquatic ecology of this riverine ecosystem. [ABSTRACT FROM AUTHOR]

As an intermediary connection between primary producers and higher trophic levels, zooplankton are an important component of the aquatic food chain, contributing significantly to aquatic biological productivity. This study describes the zooplankton diversity and community structure, as well as their relationships with ecological factors, in homestead ponds of a coastal district along the northern Bay of Bengal region. Significant differences (p < 0.05) were detected in the mean values of temperature, pH, DO, TDS, transparency, and phosphates from the ponds during December 2020, but no significant differences were found in the nitrate levels. However, no significant variances in the ecological parameters between months were found due to the study taking place in the same season. Sixteen zooplankton species, representing four groups, were found in the study area, with the highest mean abundance of 301.19 ± 40.55 ind./L recorded in February 2021 and the lowest of 293.02 ± 21.13 ind./L recorded in December 2020. The diversity (H'), evenness (e), richness (J), and dominance (D) ranged from 2.49 to 2.12, from 0.93 to 0.84, from 2.05 to 1.56, and from 0.13 to 0.09, respectively. Based on the SIMPER analysis, Diaptomus gracilis and Brachionus calyciflorus were found to be significant contributors (>10%) to the zooplankton community structure in different months. The ANOSIM results revealed that 10 species of zooplankton were significant contributors based on their average dissimilarity. The canonical correspondence analysis (CCA) identified that pH, transparency, nitrates, and phosphates have a significant impact on the abundance of zooplankton species in the homestead ponds in the study area. [ABSTRACT FROM AUTHOR]

Grouper aquaculture is rapidly expanding in both tropical and subtropical regions. The presence of marine leeches (Pterobdella arugamensis; previously named Zeylanicobdella arugamensis) infesting cultured groupers, however, can have a fatal effect on grouper aquaculture production and cause significant economic loss. Understanding the marine leech's population structure is therefore important to determine its possible distributional origin and distributional mechanisms, which will help monitor and mitigate the infestation. In this study, a total of 84 marine leeches collected from cultured hybrid groupers Epinephelus spp. in Brunei Darussalam, Malaysia and Indonesia were identified as P. arugamensis, based on morphological and mitochondrial cytochrome c oxidase subunit I gene sequence analyses. These leech samples, together with additional sequences from the GenBank database, were grouped into four genetically distinct haplogroups: (1) Asia Pacific, (2) Borneo, (3) Surabaya and (4) Iran. The four populations were found to be highly diverged from each other. The results also suggested that the samples from the Asia Pacific population could be dispersed and transported from Indonesia. [ABSTRACT FROM AUTHOR]

The cladocera Moina macrocopa serves as a common live feed that is suitable for most freshwater fish species. Seven diets for the cladocera, viz. Chlorella sp., rice bran, soybean meal, chicken manure, swiftlet waste, canola oil, and artificial micro pellet were compared in this study. This study's objective was to analyse the effect of enriched M. macrocopa on the growth, survival, and dietary profiles of hybrid Nile tilapia fry. The feeding experiment lasted for over 60 days. The M. macrocopa enriched with rice bran has produced the highest weight gain (5.83 g), survival (86.67%), protein (24.88%), and lipid (6.85%) in Nile tilapia fry. While, fatty acid such as α-linolenic acid (ALA; 4.67%) was found to be the highest in fry fed with M. macrocopa enriched with soybean meal. Arachidonic acid (ARA; 3.69%) and docosahexaenoic acid (DHA; 0.47%) were the highest in tilapia fry fed with M. macrocopa enriched with rice bran, while eicosapentaenoic acid (EPA; 6.33%) was the highest in tilapia fry fed with M. macrocopa enriched with Chlorella sp. In conclusion, the manipulation of nutrient such as protein, lipid and fatty acid Scompositions in M. macrocopa diet has successfully improved the nutrient compositions and production of Moina sp. culture that indirectly increased the growth and survival of hybrid tilapia fry. [ABSTRACT FROM AUTHOR]

A 105-day experimental trial was conducted to assess different levels of dietary Aleo vera extract supplementation on water quality parameters, proximate composition, growth performance and haematological parameters of fry Oreochromis niloticus. Four different percentages of dietary leaf extract powder of Aleo vera (ALE) with a basal feed, designated as, i.e., T0 (Control group; without ALE), T1 (1% ALE), T2 (2% ALE), and T3 (3% ALE). Fish fry was reared in concrete tanks (7.0 m, 1.6 m, 1.0: L, W, H; water volume 11.2 m3/tank), with an average initial weight 4.04 ± 0.03 g/ fry, and each treatment was triplicated. Fry was randomly distributed at a stocking rate of 450 individuals/ tanks. The water quality parameters revealed that temperature, pH, salinity, dissolved oxygen (DO) and nitrates were found in a promising range as given by FAO/WHO limits. However, the record values obtained for Electric Conductivity (EC), Total dissolved solids (TDS), and alkalinities were not found in all tanks' suitable range according to FAO/WHO limits. The results revealed a significant impact of different percentages of dietary ALE supplementation on fry's body composition and haematological parameters. Moreover, the final body weight, final body length, average daily weight gain (g), net weight gain (g) and specific growth rate (%) were significantly higher (p < 0.05) in T1 and T2 compared with T0 and T3 treatments. The poorest feed conversion ratio was recorded in the T2 group compared with other treatments. Thus, the current study provides information about the nutritional quality of Nile tilapia culturing in Pakistan. [ABSTRACT FROM AUTHOR]

In the aquaculture of fish and crustaceans, the indoor culture of M. macrocopa constitutes a requisite to produce a more effective feed for the larviculture of the cultured commercial species. The present study examined the efficiency of different diets on population density, survival, and productivity of M. macrocopa. The cladocerans [Cladocera: currently largely referred to as Diplostraca] were fed and enriched with seven diets, including Chlorella sp., agro-industrial residues (rice bran and soybean meal), bio-organic fertilizer (chicken manure and swiftlet waste), canola oil and artificial micro pellets. The diets were provided at a concentration of 500 mg/l for each diet. The M. macrocopa fed on rice bran had a higher population density, survival, productivity, and a promising higher nutrient quality than the test groups fed on the other dietary treatments used. This study has covered the most important aspects of nutritional requirements to produce live feed organisms, which would provide a comprehensive data set for an alternative solution of the best feed for M. macrocopa propagation and their utilization in hatcheries. Résumé: En aquaculture de poissons et de crustacés, l'élevage en intérieur de M. macrocopa constitue un prérequis pour produire une nourriture plus efficace pour la production de larves des espèces commerciales élevées. Cette étude examine l'efficacité de différents régimes sur la densité de population, la survie et la productivité de M. macrocopa. Les cladocères [Cladocère : actuellement largement nommé Diplostraca] ont été nourris et enrichis avec sept régimes, incluant Chlorella sp., des résidus agro-alimentaires (riz brun et farine de soja), engrais bio-organiques (fumier de poulet et déchets de salangane), huile de canola et micro granulés artificiels. Les régimes ont été donnés à une concentration de 500 mg/l chacun. Les M. macrocopa nourris avec le riz brun ont eu une densité de population, une survie, une productivité plus élevées, et une qualité nutritive potentiellement plus élevée que les groupes nourris avec les autres régimes testés. Cette étude s'est intéressée aux aspects les plus importants des besoins nutritionnels pour produire une nourriture vivante, et pourrait fournir un ensemble de données pour une solution alternative à une meilleure nourriture pour M. macrocopa et leur utilisation généralisée en écloseries. [ABSTRACT FROM AUTHOR]

Extrusion-based three-dimensional (3D) bio-printing deposits cell-laden bio-ink with high spatial resolution and may offer living tissue regeneration. Due to the biocompatibility, very low cytotoxicity, and high-water content, natural hydrogels are commonly considered as the cell-laden bio-ink for scaffold fabrication. However, due to the low mechanical integrity, a large-scale scaffold (>10 layers) with intricate architecture is a challenge. In this paper, we developed and characterized a novel bio-ink consisting of alginate, carboxymethyl cellulose (CMC), and 2,2,6,6 tetramethyl-1-piperidinyloxy (TEMPO)-mediated nanofibrillated cellulose (TO-NFC) for bio-printing applications. The potential of cellulose derivatives in terms of rheological property to satisfy scaffold architecture and cell viability is explored with a relatively small amount of solid content (<5%). By combining alginate, CMC, and TO-NFC as a hybrid hydrogel, we design to overcome their individual challenges as bio-ink. At the design stage, we have considered two main characteristics: printability and shape fidelity with quantitative indices following their rheological characteristics. Our proposed hydrogel blend (5% solid content) demonstrates a 0% collapse rate for 3-mm pillar distance and 25% fusion rate for 5 mm × 5 mm pore size which can ensure shape fidelity. We fabricated 42 layers and a 9-mm tall scaffold structure with relatively lower applied pressure (10 psi). The proposed hybrid hydrogel is used to prepare bio-ink encapsulating cells, and cell viability is measured as 90% after 10 days of incubation. [ABSTRACT FROM AUTHOR]

Seaweeds can play an essential role in controlling antibiotic resistance for bacterial diseases. Three extracts of two brown seaweeds Padina tetrastromatica and Sargassum ilicifolium were investigated as growth promoters and to provide immune protection against Vibrio parahaemolyticus. Extracts of the two seaweeds were administered at 2.5 and 5 g kg−1 with food for 45 days to Penaeus monodon juveniles. The maximum weight gain (6.28 and 7.08 g), specific growth rate (3.39 and 3.32%), and survival rate (78.45 and 82.45%) of the juvenile tiger shrimp were obtained at a dose of 5 g kg−1 with P. tetrastromatica extracted by methanol and ethanol, respectively; which was significantly higher than the other solvents and control group (p <.01). On the other hand, methanol extract of both seaweeds had maximal antibacterial activity against V. parahaemolyticus with zones of inhibition ranging between 20.25 ± 1.00 and 22.00 ± 0.50 mm. The minimal time required for haemolymph clotting was with methanol extracted of P. tetrastromatica at 5 g kg−1, which was significantly lower than the other groups (p <.05). After challenging with V. parahaemolyticus, the total haemocyte count (THC) in P. monodon treated with methanol-extract of P. tetrastromatica diet at 5 g kg−1 was higher (5.42 × 105 cells mL−1) but not significantly different than the other diets (p >.05). However, the administration of 5 g kg−1 methanol and ethanol extract of P. tetrastromatica improved growth performance and the immune capacity of P. monodon by increasing their phenoloxidase activity, superoxide anion concentration, and resistance against V. parahaemolyticus. The maximum growth performance and survival of juvenile tiger shrimps obtained with Padina tetrastromatica extract at a dose of 5 g kg−1. The methanol extract of P. tetrastromatica and Sargassum ilicifolium had maximal antibacterial activity against V. parahaemolyticus. The administration of 5 g kg−1 methanol and ethanol extract of P. tetrastromatica improved growth performance and the immune capacity of P. monodon. [ABSTRACT FROM AUTHOR]

The population genetic diversity and demographic history of the longtail tuna Thunnus tonggol in Malaysian waters was investigated using mitochondrial DNA D-loop and NADH dehydrogenase subunit 5 (ND5). A total of 203 (D-loop) and 208 (ND5) individuals of T. tonggol were sampled from 11 localities around the Malaysian coastal waters. Low genetic differentiation between populations was found, possibly due to the past demographic history, dispersal potential during egg and larval stages, seasonal migration in adults, and lack of geographical barriers. The gene trees, constructed based on the maximum likelihood method, revealed a single panmictic population with unsupported internal clades, indicating an absence of structure among the populations studied. Analysis on population pairwise comparison ФST suggested the absence of limited gene flow among study sites. Taken all together, high haplotype diversity (D-loop = 0.989-1.000; ND5 = 0.848-0.965), coupled with a low level of nucleotide diversity (D-loop = 0.019-0.025; ND5 = 0.0017-0.003), "star-like" haplotype network, and unimodal mismatch distribution, suggests a recent population expansion for populations of T. tonggol in Malaysia. Furthermore, neutrality and goodness of fit tests supported the signature of a relatively recent population expansion during the Pleistocene epoch. To provide additional insight into the phylogeographic pattern of the species within the Indo-Pacific Ocean, we included haplotypes from GenBank and a few samples from Taiwan. Preliminary analyses suggest a more complex genetic demarcation of the species than an explicit Indian Ocean versus Pacific Ocean delineation. [ABSTRACT FROM AUTHOR]

Eighty-four specimens collected from 13 populations from Malaysia, Thailand, and Vietnam were analysed, revealing 21 putative haplotypes with overall estimated haplotype and nucleotide diversities of 0.79 and 0.0079, respectively. High levels of diversity and an absence of founder effects were observed among populations in peninsular Malaysia. In contrast, populations from Sarawak exhibited low genetic diversity, which is a typical sign of colonies introduced from a single source. Historical translocation of Trichopodus pectoralis from Thailand to Malaysia, as well as to the Philippines, Indonesia, and Myanmar was apparent. Historical introduction of T. pectoralis from Vietnam was also detected in peninsular Malaysia. [ABSTRACT FROM AUTHOR]

The Karnaphuli River estuary, located in southeast coast of Bangladesh, is largely exposed to heavy metal contamination as it receives a huge amount of untreated industrial effluents from the Chottagram City. This study aimed to assess the concentrations of five heavy metals (As, Pb, Cd, Cr and Cu) and their bioaccumulation status in six commercially important fishes, and also to evaluate the potential human health risk for local consumers. The hierarchy of the measured concentration level (mg/kg) of the metals was as follows: Pb (13.88) > Cu (12.10) > As (4.89) > Cr (3.36) > Cd (0.39). The Fulton's condition factor denoted that fishes were in better 'condition' and most of the species were in positive allometric growth. The bioaccumulation factors (BAFs) of the contaminants observed in the species were in the following orders: Cu (1971.42) > As (1042.93) > Pb (913.66) > Cr (864.99) > Cd (252.03), and among the specimens, demersal fish, Apocryptes bato appeared to be the most bioaccumulative organism. Estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and carcinogenic risk (CR) assessed for potential human health risk implications suggest that the values were within the acceptable threshold for both adults and children. However, calculated CR values indicated that both age groups were not far from the risk, and HI values demonstrated that children were nearly 6 times more susceptible to non-carcinogenic and carcinogenic health effects than adults. [ABSTRACT FROM AUTHOR]

While one concussion knocks players out from game, succession of it scratches literally them out from sports. Helmet is one of the main protective components, saves players from concussion. The existing head gears are standardized meaning 'One size fits all' which may not serve well protecting individuals. Our objective is to develop a generative sports helmet design ensuring smartness, player-specificity, and player-adaptability and allowing for realistic manufacturing of the prototypes. Our engineered measurement and design approach will provide a quick and easy platform for customized shape digitization. Our recently developed customizable 3d printing equipment will be used to manufacture the helmet., This research will allow manufacturer to select appropriate material, incorporate design criteria and even cost optimization in accordance to the individual player requirement. Ahasan Habib * (G) and Bashir Khoda [...]

Three-dimensional (3D) bio-printing is a revolutionary technology to reproduce a 3D functional living tissue scaffold in-vitro through controlled layer-by-layer deposition of biomaterials along with high precision positioning of cells. Due to its bio-compatibility, natural hydrogels are commonly considered as the scaffold material. However, the mechanical integrity of a hydrogel material, especially in 3D scaffold architecture, is an issue. In this research, a novel hybrid hydrogel, that is, sodium alginate with carboxymethyl cellulose (CMC) is developed and systematic quantitative characterization tests are conducted to validate its printability, shape fidelity and cell viability. The outcome of the rheological and mechanical test, filament collapse and fusion test demonstrate the favorable shape fidelity. Three-dimensional scaffold structures are fabricated with the pancreatic cancer cell, BxPC3 and the 86% cell viability is recorded after 23 days. This hybrid hydrogel can be a potential biomaterial in 3D bioprinting process and the outlined characterization techniques open an avenue directing reproducible printability and shape fidelity. [ABSTRACT FROM AUTHOR]

Motivation: Proper management of fecal sludge has significant positive health and environmental externalities. Most research on managing onsite sanitation so far either simulates the costs of, or the welfare effects from, managing sludge in situ in pit latrines. Thus, designing management strategies for onsite rural sanitation is challenging, because the actual costs of transporting sludge for treatment, and sources for financing these transport costs, are not well understood. Methods: In this paper we calculate the actual cost of sludge management from onsite latrines, and identify the contributions that latrine owners are willing to make to finance the costs. A spreadsheet-based model is used to identify a cost-effective transport option, and to calculate the cost per household. Then a double-bound contingent valuation method is used to elicit from pit-latrine owners their willingness-to-pay to have sludge transported away. This methodology is employed for the case of a rural subdistrict in Bangladesh called Bhaluka, a unit of administration at which sludge management services are being piloted by the Government of Bangladesh. Results: The typical sludge accumulation rate in Bhaluka is calculated at 0.11 liters/person/day and a typical latrine will need to be emptied approximately once every 3 to 4 years. The costs of emptying and transport are high; approximately USD 13 per emptying event (circa 14% of average monthly income); household contributions could cover around 47% of this cost. However, if costs were spread over time, the service would cost USD 4 per year per household, or USD 0.31 per month per household—comparable to current expenditures of rural households on telecommunications. Conclusion: This is one of few research papers that brings the costs of waste management together with financing of that cost, to provide evidence for an implementable solution. This framework can be used to identify cost effective sludge management options and private contributions towards that cost in other (context-specific) administrative areas where onsite sanitation is widespread. [ABSTRACT FROM AUTHOR]