Judul: Studi morfologiperbandingan induksi persembuhan kerusakan tulang oleh bahan implan tulang hidrosiapatit dan beta-trikalsiumfosfat
Abstrak: This study was conducted with aim to investigate the effectiveness implant material of Hidroxyapatite (HA):Beta-tricalcium phosphate (β-TCP) bone implant made from eggshell with ratio of HA:β-TCP 70:30 and 60:40 in inducing bone remodelling process at macroscopic and microscopic levels. Five milimeters thick implant was inserted aseptically in sheep tibia bone using surgical prosedures. Data were collected at days 30, 60 and 90 after implanted. There were no significant difference between HA:β-TCP with ratio 70:30 and 60:40 in bone remodelling process at macroscopic and microscopic observation. Remodelling process in control group was faster than HA:β-TCP implanted bone. There was no sign of rejection against HA:β-TCP implant. HA:β-TCP showed osteoinductive and osteoconductive characteristics although remodelling process was slower than the controls.
Keyword: remodelling., hidroxyapatite, bone implant, Beta-tricalcium phosphate, Beta-tricalcium phosphate, Bogor Agricultural University (IPB)

Judul: Kajian Morfologi Penggunaan Bahan Biomaterial Hidroksiapatit: β-Trikalsium Fosfat pada Kerusakan Segmental Tulang Kelinci
Abstrak: This study was conducted to examine the healing process of rabbit’s bone implanted with mixture of hydroxyapatite-tricalcium phosphate (HA:β-TCP) with mixture ratio of 70:30 and 60:40. Six New Zealand white rabbits were used in this study. Hydroxyapatite β-tricalcium phospate implanted in the medial part of the right tibia using surgical procedures, while the same part of the left tibia served as controls without implants. The samples of tibia were taken on 30 days after implantation. Parameters observed were the shape, the degradation rate of the implant, the implant bonds with the bone, new bone growth into the implant, and the signs of inflammatory reaction around the implant. The results of this study showed that the healing process in control samples was faster than bone treated with implant. There was no macroscopically morphological difference observed between the bones implanted with mixture of 70:30 and those with 60:40. But, there was difference observed microscopically. Osteocytes was observed in the bones implanted with mixture of 60:40 and there was no osteocytes observed in the bones implanted with mixture of 70:30. At day 30, the implant of HA:β-TCP showed potency of biodegradability, bioresorbability, osteoconductivity, and good biocompatibility for body. It is suggested that the next research of this mixture as bone implant is still needed to find the optimal composition
Keyword: Bogor Agricultural University (IPB), rabbit bone, hydroxyapatite, healing process, bone implants, beta-tricalcium phosphate

Judul: Model Input-output dalam Masalah Network Flow
Abstrak: Production process is a process, which is done by industry, to transform input into output. According to the type of output and its activity, industry can be classified into various sectors, which are connected to each other. Therefore, a model to analyze the connection among sections is needed. The model is known as input-output model (IO model). IO model presents an IO table, which shows informations about the transaction between goods and services in each economic sector. Furthermore, the IO model also shows that the amount of all input is the same as the amount of all output. In this paper, the transaction of each economic sector in IO table is analyzed using network flow theory. The formulated network flow problem implies that each sector represents partly as a producer and also as a consumer. This paper also solves a minimum cost circulation problem.
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