Judul: Abundance of Sponges on Reef Ecosystems in Dampier Strait, Raja Ampat
Abstrak: Selat Dampier merupakan salah kawasan konservasi perairan Raja Ampat, bagian coral triangle. Kondisi terumbu karang di Selat Dampier termasuk dalam kondisi yang baik. Spons termasuk filum porifera yang bersifat sessile dan filter feeder. Komunitas spons dapat menjadi salah satu bioindikator. Secara ekologis, spons merupakan salah satu biota penyusun ekosistes terumbu karang. Tujuan dari penelitian ini adalah mengetahui kelimpahan spons yang berada di Selat Dampier dengan menggunakan metode Underwater Photo Transect (UPT). Kondisi terumbu karang pada Selat Dampier tergolong cukup baik (30,29%) dan didominasi oleh tutupan karang keras. Hasil identifikasi spons didapatkan 506 individu dari 93 spesies, 66 genus, 41 famili, dan tiga kelas. Demospongia merupakan kelas paling sering dijumpai. Famili yang paling banyak ditemukan adalah Chalinidae dengan total individu 56. Selain itu, Chalinidae merupakan famili dengan spesies terbanyak, yaitu delapan spesies. Aaptos suberitiodes adalah spesies dengan total individu terbanyak, yaitu 35 individu. Hasil correspondence analysis menunjukkan adanya asosiasi antara komunitas spons dengan tutupan karang keras dan rubble., Dampier Strait is one of the water areas of Raja Ampat, included the coral triangel. The condition of coral reefs in Dampier Strait is good condition. Sponges are phylum Porifera which are sessile and filter feeder. Sponge communities can be one of the bioindicator. Ecologically, sponges are one of the constituent biota of reef ecosystems. The objective of this study is determine the abundance of sponges in Dampier Strait using the Underwater Photo Transect (UPT) method. The condition of coral reefs in the Dampier Strait is quite good (30,29%) and dominated by hard corals. The results of sponge identification are 506 individuals from 93 species, 66 genera, 41 families, and three classes. Demospongia are the classes most often found. The most common family found is Chalinidae with a total of 56 individuals. Moreover, Chalinidae is the family with the most species, which is eight species.Aaptos suberitiodes is the species with the largest total number of individuals studied, 35 individuals. The results of correspondence analysis show an association between sponge communities with hard coral and rubble cover.
Keyword: abundance, Dampier Strait, coral reefs, sponge

Judul: Identification of Sponge Species Based on Morphology and Genetics in Raja Ampat, West Papua
Abstrak: Invertebrata laut termasuk kelompok hewan tidak bertulang belakang yang berperan dalam menjaga kestabilan ekosistem laut. Banyak spesies invertebrata laut yang belum teridentifikasi, salah satunya biota spons. Keberadaan spons tidak banyak diapresiasi, dipelajari dan diteliti dengan baik dibandingkan dengan biota laut lainnya. Beberapa penelitian terkait spons paling banyak dilakukan di wilayah Jawa dan Sulawesi. Penelitian terkait genetik dan tipe spikula tidak banyak dilakukan di Perairan Indonesia. Kesulitan identifikasi morfologi dan taksonomi menjadi salah satu faktor minimnya informasi terkait data spons. Tujuan penelitian ini yaitu mengetahui jenis-jenis spons yang ada di perairan Raja Ampat berdasarkan tipe spikula dan genetik. Identifikasi spesies berdasarkan genetik dilakukan dengan BLAST (Basic Local Alignment Search Tool) pada Genbank di NCBI (National Centre For Biotechnology Information) menggunakan data sekuen yang diperoleh dari sampel setelah melalui tahapan ekstraksi, PCR, elektroforesis, dan sekuensing. Rekonstruksi pohon filogeni dibuat menggunakan model Kimura 2-parameter dengan metode Neighbour Joining dan Maximum Parsimony. Identifikasi bentuk spikula spons dilakukan dengan pengamatan preparat menggunakan mikroskop majemuk. Berdasarkan analisis laboratorium dari 22 sampel ditemukan 5 sampel terdeteksi sebagai spesies spons Halichondria sp., Stylissa carteri, Xestospongia deweerdtae, dan Theonella sp. Rekonstruksi pohon filogeni menghasilkan empat clade besar. Bentuk tipe spikula yang teramati terdiri dari spikula monoaxon dan tetraxon., Marine invertebrates are a group of invertebrate animals that play a role in maintaining the stability of marine ecosystems. Many marine invertebrate species have not been identified, one of which is the sponge. The existence of sponges is not much appreciated, studied and well researched compared to other marine biota. Most research related to sponges has been carried out in Java and Sulawesi. Research related to genetics and spicule types is not much carried out in Indonesian. The difficulty of identifying morphology and taxonomy is one of the reasons for the lack of information related to sponge data. The purpose of this study was to determine the types of sponges in Raja Ampat based on the type of spicules and genetics. Genetic identification of species was carried out using BLAST (Basic Local Alignment Search Tool) on Genbank at NCBI (National Center For Biotechnology Information) using sequence data obtained from samples after going through the stages of extraction, PCR, electrophoresis and sequencing. Phylogenetic tree reconstruction was made using the Kimura-2 parameter model with the Neighbor Joining and Maximum Parsimony methods. Identification of the shape of sponge spicules was carried out by observing the preparations using a compound microscope. Based on laboratory analysis of 22 samples, it was found that 5 samples were detected as Halichondria sp., Stylissa carteri, Xestospongia deweerdtae, and Theonella sp. Phylogenetic tree reconstruction resulted in four large clades. The types of spicules observed consisted of monoaxon and tetraxon spicules.
Keyword: DNA barcoding, genetic, spicule, sponge

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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