An examination of the effectiveness of traps and baits as a possible means of harvesting crayfish, Cherax quadricarinatus in Sanyati Basin, Lake Kariba, Zimbabwe

Although Cherax quadricarinatus is now established in Lake Kariba, there is a lack of information on the appropriate gear technology and bait for its exploitation for either management or commercial purposes. The effectiveness of three trap designs and three bait types was investigated in order to identify the best means for harvesting C. quadricarinatus in Lake Kariba. The cylindrical and rectangular traps had higher and similar CPUE, which were significantly higher than those of the Opera house trap at all sites. Trap type did not influence sex ratio. Liver, sadza and fish heads were all similarly effective as bait. Either sadza-baited cylindrical or rectangular traps can be effectively employed to either harvest crayfish in order to maintain a low population, thereby mitigating potential adverse impacts, or for commercial purposes. This should be corroborated with monitoring and further research.

KARAKTERISTIK TALI AGEL BERKITOSAN SEBAGAI BAHAN ALAT PENANGKAPAN IKAN

Agel ropes have lower mechanical properties (breaking strength and elongation) than synthetic fiber ropes. Chitosan coating is expected to improve the mechanical properties of agel ropes. The aims of this study are to investigate the effect of immersion in chitosan on the physical and mechanical properties of agel ropes, and to examine the breaking strength and elongation of coated agel ropes after being soaked in both freshwater and seawater. This experimental study was conducted at the Laboratory of Fishing Gear Technology, Department of Fisheries Resources Utilization IPB University, and Laboratory of Forest Product Engineering, Department of Forest Products IPB University. The experiment involved 3 mm in diameter of two agel ropes incorporating control rope and agel rope soaked in 1% chitosan for 24 hours. The control rope was light brown, stiff, and rough, while the treated rope was darker, less stiff, and smoother. The breaking strength of control and treated rope was significantly different (P<0.05), which in respect constitute 15.06 kgf and 24.54 kgf. The elongation of both ropes were also significantly different (P<0.05), making 10,56% for control and 18,04% for treated rope. Breaking strength of the agel rope decreased by 50% after being immersed for 28 days. Keywords: agel rope, chitosan, breaking strength, elongation

The impact of rule changes on the number and severity of injuries in the NFL

Injuries in the National Football League (NFL) are a concern for reasons of performance, revenue, and player health. In particular, recent discoveries highlighting the long-term repercussions of concussions has drawn popular attention to the violence of the sport of American football and shone a bright light on the NFL's efforts to reduce injuries and their long-term impact. While studies have largely focused on the impact of injuries on players' long-term health, there has been less independent work on the evolution of injuries, namely in how the number and extent of injuries have changed over the years and what role, if any, the NFL has played in improving these figures by changing the rules or by improving protective gear technology. Here, we studied injuries from eight seasons 2010-2017, i.e. and address the impact of major rule changes that were enacted in the NFL in 2013 and 2016. We classified injuries into three major categories: arm, leg, and head, i.e. concussions. From publicly available weekly injury reports provided by each team in the NFL, we calculated the number of players who were seriously injured enough to miss at least one game of the season, and the severity of the injuries sustained, as evaluated by the number of games of the season the injured player had to sit out. The 2013 rule changes did not significantly reduce the number of players who suffered a head injury and had to sit out at least one game, and had no impact on leg or arm injuries either. Following the 2016 rule changes, we observed no change in the number of players who got injured but a significant increase in the severity of all three injury types in the two full seasons that followed. Overall, the NFL's efforts to reduce injuries and their severity have had little success, and our findings suggest instead that rule changes or technological changes cannot curb the violence and danger present in the game today.

Social Embeddedness of Pro-Environment Fisherman Community in The Use of Eco-Friendly Fishing Gear Technology at Drini Beach Gunung Kidul Yogyakarta

This study aims to determine to what extent the knowledge of the fishing communities of Gunung Kidul Yogyakarta in interpreting the use of environmentally friendly fishing technology. Also, to analyze how the form of social embeddedness related to the conservation of environmentally friendly fishing gear is seen from the dimensions of relational relationships and structural relationships in the context of social networks Coastal fishermen community Drini Gunung Kidul Yogyakarta. This study uses the sociology theory of economics from Granovetter on Social Embeddedness in "The New Economic Sociology". The research method was conducted qualitatively with phenomenology approach. The data collection was done by observation and in-depth interview. The results show that the understanding of fishing communities related to the use of environmentally friendly fishing gear technology cannot be separated from the existing social network of fishers. In the relational dimension of conservation form among fishers skipper, fisherman and fisherman who form a cooperative relationship in the fulfillment of daily necessities, including in the face of famine season, so that no fisher is desperate to use environmentally friendly fishing gear to get personal benefit Only. Meanwhile, in the structural dimension or fisherman institution, the rules on marine environment management including conservation of environmentally friendly fishing gear are among the cooperative units, and fishermen organizations under the supervision of the Office of Marine and Fishery of Yogyakarta by holding socialization and fish catching operation every three times in a year.