Judul: Aplikasi kontrol optimum pada pemanenan Sardinella lemuru di Selat Bali
Abstrak: This paper studied a mathematical model of fishery resource dynamics in an aquatic area. The considered area consists of two zones: reserve and unreserve zones, where growth of fish population on each zone is given by a nonlinear differential equation. The stability of two nonnegative fixed points are investigated by solving characteristic equation. The fixed points are saddle and stable node. More over, an optimal harvesting policy is analyzed by using Pontryagin maximum principle, from which the bang-bang and singular controls are found as optimal controls. An illustrative example is provided by considering the harvesting of Sardinella lemuru in Bali Strait. This case is simulated numerically by using fourth-order Runge-Kutta method, from which fishery resource dynamics in two zones under optimal harvesting are illustrated.
Keyword: Bogor Agricultural University (IPB), unreserve zone, reserve zone, fixed point, Pontryagin maximum principle, Runge-Kutta method

Judul: Model dinamis perikanan lemuru (Sardinela lemuru) di Selat Bali
Abstrak: Sardine fishery is single fishery in Bali Strait and has its dynamics that consist element of biology, fishing gear technology, human resources, and fish processing industries. The four subsystems are interrelated so that the fishery could lead to a dynamic system. Many studies on sardine stock estimation suggested that this fishery in Bali Strait has been over capacity. The number of purse seine fleet reached 423 units with 17,701 fishers (2009), and has 119 large industries and 370 small industries. The study aims to describe the dynamics of the sardine fishery in Bali Strait through simulation (using Powersim 2.5). The study was conducted in October and January-March 2011, Data mainly collected from secondary data of 2005 to 2010 from the Banyuwangi and Jembrana district. Analysis was using descriptive analysis method. Pressure on sardine fish resource is relatively high, so a decline in production was occurred due to over capacity. Since it is a renewable resource, recovery is still in place although cannot reach to maximum, where the MSY is 30,379.917 tons/year with EMSY is 4,600 trip/year. Scenario A of maximum production (72267.92 tons) is higher and faster (2016), but productivity per fleet is lower due to higher number of fishing fleet. Scenario B on maximum production reached 71912.15 tons, but produces one year slower production (2017), with better level of productivity due to lower number of fishing fleets. Scenario B is better from sardine resources perspective since pressure on resource is lower; hence there is a chance for natural recovery. Although, based on simulation both scenarios begin to experience the level of over capacity in 2009. Scenario A can support employment for 16,743 people, while scenario B for 13,385 people. The capacity of fish processing industry is too high compared to the existing resources; hence it is only able to produce approximately 6% of its maximum capacity. The sardine fishery is very dynamic and the fish resource could be threatened if not managed properly. Based on the simulation, we found gap between existing resources with production capacity of industry. This model has some limitation and still needs refinement to obtain better results
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Judul: Studi Kasus: Patomorfologi Trakheobronkhitis Supurativa Pada Kucing (Felis Catus).
Abstrak: Trakheobronkhitis merupakan penyakit saluran respirasi yang sering terjadi pada hewan kecil, terutama anjing dan kucing. Penelitian berupa studi kasus ini bertujuan untuk mempelajari patomorfologi trakheobronkhitis supurativa pada kucing. Perubahan patologi anatomi berupa eksudat purulen pada lumen trakhea dan warna paru-paru yang tidak homogen, warna lebih gelap pada salah satu lobus, dan permukaan paru-paru lebih menonjol. Perubahan histopatologi berupa badan inklusi amfofilik-eosinofilik intranuklear yang dikelilingi oleh clear halo dan titik-titik kromatin ditepinya pada epitel kelenjar trakhea dan epitel bronkhiolus. Badan inklusi ini merupakan ciri dari FHV-1 dan adenovirus. Pada trakhea juga ditemukan koloni bakteri berbentuk coccobacillus sebagai infeksi sekunder. Bakteri tersebut diduga Bordetella sp. yang sering menginfeksi saluran respirasi kucing. Deskuamasi terjadi pada epitel trakhea dan bronkhiolus. Selain itu, ditemukan juga sel radang limfosit, makrofag, sel plasma, dan neutrofil. Pada paru-paru ditemukan lesio bronkhiolitis. Ditemukan juga bronkhopneumonia yang ditandai infiltrasi sel radang neutrofil dan sel nekrosis pada lumen bronkhiolus. Paru-paru juga mengalami emfisema dan edema pulmonum. Hiperemia dan hemoragi juga ditemukan pada kapiler paru-paru. Pada kasus ini, trakheobronkhitis supurativa diduga disebabkan oleh FHV-1, adenovirus, dan bakteri jenis Bordetella sp.
Keyword: badan inklusi amfofilik-eosinofilik intranuklear, infeksi bakteri, kucing, patomorfologi