Judul: Kemampuan adaptif kerang bulu anadara antiquata di perairan tercemar logam berat : aspek biokinetik, ekobiologi, histologi, dan molekuler
Abstrak: The ark cockles Anadara antiquataare wide spread in Indonesia seawater, and able to live in the sediment, that are the sites of anthropogenic heavy metals deposits. A. antiquatacould not avoid the exposures ofheavy metals from surrounding environment, because of their limited mobility, and filter feeding mechanism. Muara Bama Panimbang, and Banten Bay Bojonegara in the Province of Banten, has been contaminated by heavy metals exceeding the quality standard. Panimbang areahas beenknown to have high diversity of bivalves species, thus become the center of bivalves inthe Province of Banten. A. antiquata in both location have not been exploited yet, so their economic valuesstilllow enough.Scientific information about A.antiquataarealso relatively limited, so it is interesting to study their potency,both for economical and ecological purposes. This research aimed to:1)identified the ability of mercury bioaccumulation and depuration onA. antiquata using radioactive tracer, 2) identified the effect of mercuryinduction to the histological structures of A. antiquatagills, 3) identified the ecobiological characteristics of A. antiquata in natural habitats that contaminated by heavy metals, and 4) characterizedthe metallothionein (MT)protein and gene ofA. antiquataby mercury induction. Biokinetic approachedwithradiotracer applicationhas beenconducted, to identify the capacity of mercury bioaccumulation and depurationonA. antiquata in laboratory. The results showed that smaller cockles (10-20 mm) accumulatedhigherconcentration of mercury than bigger cockles (35-45 mm). The increaseofmercury concentration in water affected the increasingof BCF values in both groups, until steady state conditions reached. Increased concentrations of mercury in water, were increased the mercuryefflux,and body contentsin both groups, but decreased the uptake rates in bigger cockles. Based on the models, lowest concentrations of dissolve mercury(0.0025 ppm) caused the highest BCF values in both groups. The steady state conditions would reachedin 15 dayson smaller cockles, andin 13 daysonbigger cockles. The mercuryelimination rates during depuration, showed no significant differences on both groups. The mercurybiological half-times in A. antiquataranged in 3.49 – 7.42 depuration days. The mercuryconcentration 0.0025; 0.005, 0.01, and 0.02 ppm have been induced for six days, to study its impact to the gills histological structures. Gills tissue samples were taken on day 2, 4, and 6 of exposures. The results showed,combination ofsix days exposuresand four mercury concentrationsdid not caused serious damages to the gills of A. antiquata.The damages appearedwerehyperplasia and necrosis, but in general,the treatmentscombinations showed no significant differences to the histological structures of gills. These facts supportsthe adaptive ability ofA. antiquata in mercury contaminated environment. The study results in natural habitat (Panimbang and Bojonegara)showed that A. antiquatawere well adaptedin heavy metals contaminated water.The shell length range in Panimbang were 8.05 - 24.65 mm (average 18.696 ± 5.946 mm), while in Bojonegara ranged 16.85 - 51.85 mm (average 25.87 ± 8.593 mm). The index of Meat Yieldsresults showed that 58.38% samples inPanimbang,and 53.85% samples inBojonegara,categorizedin moderate class, that reflectedthe ability to stored organic compounds reservesfor growth and reproduction, although they lived incontaminated environment. The Pb contents in cocklesbody ranged between 0.125-2.50 ppm; Cd contents ranged 0.125-17.60 ppm, and Hg ranged 0.02-0.3 ppm.The heavy metals contents in cocklesat Bojonegara was higher than Panimbang. The molecular studyhas beenidentifiedthe metallothionein (MT) proteinfrom hepatopancreas, and the MT gene from gills of A. antiquata.
Keyword: Anadara antiquata, heavy metals bioconcentration factor, metallothionein, ecobiology

Judul: Kandungan Logam Berat Pb, Hg, Cd, dan Cu pada Kerang Darah (Tegillarca granosa) di Perairan Pantai Bojonegara, Teluk Banten
Abstrak: Teluk Banten merupakan wilayah perairan yang memiliki beberapa muara sungai. Aliran sungai tersebut diperkirakan membawa limbah dari kegiatan domestik maupun industri, salah satu jenis limbah tersebut adalah logam berat. Penelitian ini bertujuan mengestimasi akumulasi kandungan logam berat yang terdapat pada daging kerang darah (Tegillarca granosa) di perairan Pantai Bojonegara, Teluk Banten. Sampel kerang darah diambil pada bulan Agustus-Oktober 2020, dan Maret 2021 di perairan Pantai Bojonegara, Teluk Banten. Kandungan logam berat diukur dengan alat AAS (Atomic Absorption Spectrophotometer). Kandungan logam berat Pb, Hg, Cd, dan Cu dalam daging kerang darah secara berurutan bernilai kurang dari 0,03 mg kg-1, kurang dari 0,001 mg kg-1, kurang dari 0,005 mg kg-1, serta kisaran 0,634-5,48 mg kg-1. Kandungan logam berat Pb, Hg, dan Cd pada kerang darah tidak melampaui batas maksimal yang diperbolehkan BPOM (2018) dan FAO/WHO (2011). Namun, kandungan logam berat Cu sudah melebihi batas mutu yang ditetapkan FAO/WHO (2011). Faktor biokonsentrasi kerang darah pada ukuran kecil dan ukuran besar memiliki sebaran nilai mulai dari rendah, sedang, hingga tinggi. Kandungan logam berat berkaitan erat dengan ukuran tubuh kerang darah., Banten Bay is the water that has several estuaries. The flow of these rivers can carry waste from domestic and industrial activities such as heavy metals. This study estimates the accumulation of heavy metals in the flesh of blood cockle (Tegillarca granosa) in Bojonegara Coastal Waters, Banten Bay. Blood cockle samples were collected in August-October 2020 and March 2021 in Bojonegara coastal waters, Banten Bay. Heavy metal content was measured using AAS (Atomic Absorption Spectrophotometer). The heavy metal content Pb, Hg, Cd, and Cu in blood cockle meat, respectively, were less than 0.03 mg kg-1, less than 0.001 mg kg-1, less than 0.005 mg kg-1, and range 0.634-5.48 mg kg-1. The heavy metal content of Pb, Hg, and Cd in the blood cockle did not exceed the maximum allowable limit by BPOM (2018) and FAO/WHO (2011). However, the Cu concentration was above the specified quality standard by FAO/WHO (2011). The bioconcentration factor values of blood cockle in small and large sizes range from low, medium, to high. The concentration of heavy metals in blood cockle meat is related to its body size.
Keyword: Blood cockle, Heavy metals, Banten Bay

Judul: Kajian frieze groups untuk klasifikasi dan konstruksi desain berdasarkan simetri pada pola
Abstrak: Frieze groups adalah konsep matematika untuk mengklasifikasikan desain pada dua dimensi permukaan yang berulang-ulang dalam satu arah berdasarkan simetri pada pola. Frieze groups merupakan grup yang mempertahankan bentuk pola. Pergerakan bentuk pola terdiri dari translasi, refleksi dan rotasi 180o. Tujuan dari karya ilmiah ini adalah mengkaji sifat Frieze group, mengkaji penggunaan Frieze group dalam mengklasifikasikan simetri pada pola dan mengkonstruksi pola dengan menggunakan software tesselmania. Hasil yang telah diperoleh, bahwa jenis Frieze groups merupakan subgroup dari grup pergerakan pola. Selain itu dapat dilihat dari sifat isomorfik berbagai jenis Frieze groups. Untuk mengkonstruksi sebuah bentuk pola dapat menggunakan salah satu software untuk membentuk sebuah pola bidang datar (dua dimensi) yaitu tesselmania.
Keyword: Frieze groups, Simetri, Pola