The Effect of Storage Diversity on the Breaking Strength and Elongation of Polyamide Monofilament in Gill Net Fishing Gear

The study aimed to determine the breaking strength and elongation of polyamide monofilament 0.44 mm in dry condition after treating with open and close storage. This study was an experimental study that refers to SNI ISO 1805: 2010 method. Data collection was done in the dry condition with two yarn samples from different treatments and one sample as a control. Each treatment was done 10 times of repetition. The test material was collected in one mesh. Then the locking distance was adjusted with the mesh size. The breaking strength and elongation score were tested using an autograph. The study found the breaking strength on polyamide nets stored closely was higher than open storage samples. On the other, the elongation value on monofilament polyamide nets stored closely was lower than open storage samples. There was an effect on different storage methods against polyamide breaking strength (sig 0.00), which was lower than α (0.05). Different storage methods also affected the elongation score of polyamides (sig 0.00) < α (0.05). In conclusion, there was an effect on different storage methods, open or close storage, against breaking and elongation strength of polyamide monofilament 0.4 mm.

In Vitro Tensile Strength Study on Suturing Technique and Material

Suture technique and materials are important in preventing complications such as wound dehiscences. The purpose of this study was to determine the tensile strength of different suturing techniques, comparing several materials with different diameters. One hundred sixty sutures were performed using silk, e-PTFE, and 2 types of polyamide (monofilament and Supramid). Ten simple, 10 horizontal mattress, and 10 combinations of the two stitches were performed with 4-0 gauge of each material. Additionally, 10 simple sutures were performed with the 5-0 gauge of each material. The maximum tensile force resisted by each suture was recorded. When 5 mm of traction was applied, the polyamide monofilament resisted significantly better without untying or breaking compared with Supramid or silk, while the e-PTFE was superior to all the others. However, the force when e-PTFE 4-0 sutures untied or broke was lower than for either type of polyamide. The combined technique withstood a significantly higher tensile force before unknotting or breaking than did the simple and mattress stitches. The 5-0 gauges of silk and both types of polyamide showed lower tensile strengths than the 4-0 materials. Among the 5-0 sutures, Supramid showed a higher tensile strength than silk. The combined suture technique possessed greater tensile strength than did a simple or a horizontal mattress suture, and e-PTFE 4-0 withstood more traction without untying or breaking than did all the other materials, although at a lower tensile force. With the exception of e-PTFE, 4-0 sutures had greater tensile strength than did 5-0 sutures.

Pelagic Longline Fishing Gear: A Brief History and Review of Research Efforts to Improve Selectivity

Pelagic longline gear had several independent evolutions, but the most widespread form appears to have been originally developed by the Japanese as early as the mid-19th century. Technological developments such as polyamide monofilament line and modern fishing vessel construction have resulted in the evolution and expansion of this gear type as the primary worldwide method of commercially harvesting large pelagic fishes such as broadbill swordfish and tunas. Although the adaptability of the gear through changes in materials, lengths, and deployment strategies has resulted in generally high selectivity for many target species, the bycatch of protected species by pelagic longlines is considered a global problem in the conservation effort to sustain populations of sea turtles, sea birds, and some istiophorid billfishes (sailfishes; spearfishes; marlins). Recent research on the modification of pelagic longline fishing strategies uses this inherent adaptability of the gear to avoid or reduce the mortality of bycatch species. This is an alternative to the traditional management strategy of closed areas, which fishermen view as less effective and generally more restrictive (limiting) with respect to target catches. This work with academic partners and commercial fishermen has resulted in the development of bycatch reduction strategies which include safe handling and release gear and protocols, use of circle hooks in place of traditional J-style hooks, restrictions on gangion and mainline lengths, and corrodible hooks.