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"Telah dilakukan penelitian bioakumulasi plutonium dan americium oleh Babylonia spirata dari Teluk Jakarta menggunakan perunut 242Pu dan 243Am. Eksperimen akuaria menggunakan dua jenis tingkat oksidasi. dan. dengan tiga kali pengulangan. Percobaan dilakukan melalui. tahapan, yaitu akumulasi dan depurasi. Bioavailabilitas 242Pu Pu3 dan Pu4 dan 243Am Am3 dan Am4 di air laut pada Babylonia spirata telah dipelajari. Parameter biokinetika yang diteliti meliputi faktor konsentrasi CF, konstanta laju pengambilan ku, konstanta laju pelepasan ke, faktor biokonsentrasi BCF, dan waktu paruh biologis tb1/2. Spesiasi 242Pu Pu3 dan Pu4 dan 243Am Am3 dan Am4 menunjukkan pengaruh yang berbeda terhadap kemampuan B. spirata mengakumulasi Pu dan Am. Bentuk Pu4 dan Am3 terakumulasi lebih tinggi dan tertahan lebih lama di kompartemen tubuh B. spirata. Radionuklida 242Pu dan 243Am terdistribusi paling tinggi pada cangkang dan sisa organ, dan terdistribusi paling rendah pada insang dan ginjal B. spirata.

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The research of bioaccumulation Plutonium and Americium of Babylonia spirata from Jakarta Bay using 242Pu and 243Am radiotracers has been conducted. The aquaria experiments were applied by two oxidation states of Pu and Am speciation with three replications. The experiment was carried out by. steps, such as uptake and depuration. The bioavailability of 242Pu and 243Am in the III and IV oxidation states through sea water pathway has been studied for Babylonia spirata. Biokinetics parameters, such as concentration factors CFss, uptake rate constants ku, elimination rate constants ke, bioconcentration factors BCF, and biological half life tb1 2, were investigated. Speciation of 242Pu Pu3 dan Pu4 dan 243Am Am3 dan Am4 affected the ability of B. spirata to accumulates plutonium and americium. The research shows that Pu4 and Am3 are potentially accumulated in greater value than Pu3 and Am4 by B. spirata, in which Pu and Am are more rapidly distributed and retained longer in shells and remainders, and shorter in gills and kidneys."

"Plutonium dan Americium merupakan produk fisi dari aktivitas fasilitas nuklir. Operasional fasilitas nuklir kemungkinan melepas radioisotop tersebut ke lingkungan. Dalam lingkungan perairan laut Pu dan Am terspesiasi menjadi beberapa bentuk senyawaan kimia. Perna viridis mampu mengakumulasi kedua radioisotop tersebut yang dipengaruhi oleh bentuk spesiasinya. Penelitian ini bertujuan untuk memperoleh bioindikator kontaminan Pu dan Am menggunakan Perna viridis. Percobaan dilakukan mulai dari pengambilan biota, bioakumulasi dan depurasi. Parameter biokinetika yang diteliti meliputi faktor konsentrasi (CF), konstanta laju pengambilan (ku), konstanta laju pelepasan (ke), faktor biokonsentrasi (BCF), dan waktu paruh biologis (tb1/2). Pada studi ini dilakukan pengamatan organ sasaran bioakumulasi Pu dan Am pada Perna viridis. Spesiasi 242Pu (Pu3+ dan Pu4+) dan 243Am (Am3+ dan Am4+) menunjukkan pengaruh yang berbeda terhadap kemampuan Perna viridis mengakumulasi Pu dan Am. Pada percobaan diperoleh salah satunya parameter biokinetika dengan nilai CF Pu3+ pada insang, pencernaan dan sisa organ berturut-turut sebesar 7,0 mL.g-1; 8,8 mL.g-1 dan 8,0 mL.g-1. Nilai CF Pu4+ pada insang, pencernaan dan sisa organ berturut-turut sebesar 8,8 mL.g-1; 10,4 mL.g-1 dan 9,8 mL.g-1. Nilai CF Am3+ pada insang, pencernaan dan sisa organ berturut-turut sebesar 18 mL.g-1; 22,5 mL.g-1 dan 19 mL.g-1. Nilai CF Am4+ pada insang, pencernaan dan sisa organ berturut-turut sebesar 16,5 mL.g-1; 20 mL.g-1 dan 17 mL.g-1. Isotop Pu4+ dan Am3+ terakumulasi lebih tinggi dan tertahan lebih lama di kompartemen tubuh P. viridis daripada Pu3+ dan Am4+. Isotop Pu4+ dan Am3+ terdistribusi paling tinggi di kompartemen tubuh bagian pencernaan daripada di bagian insang. Berdasarkan eksperimen diasumsikan bahwa Perna viridis dapat dijadikan sebagai bioindikator.

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Plutonium and Americium are fission products from the activities of nuclear facilities. The operation of nuclear facilities is likely to release the radioisotope into the environment. In the marine environment Pu and Am form speciation into several forms of chemical compounds. Perna viridis can accumulate the two radioisotopes which are affected by the shape of the speciation. One of the parameters that influence the accumulation ability is Pu and Am speciation.This study aims to obtain Pu and Am contaminant bioindicators using Perna viridis. Experiments were carried out starting from taking biota, bioaccumulation, and depuration. Biokinetics parameters, such as concentration factors (CF), uptake rate constants (ku), elimination rate constants (ke), bioconcentration factors (BCF), and biological half-life (tb1/2), were investigated. In this study, observation of Pu and Am bioaccumulation target organs in Perna viridis. Speciation of 242Pu (Pu3+ dan Pu4+) dan 243Am (Am3+ dan Am4+) affected the ability of Perna viridis to accumulates plutonium and americium. In this study Pu observed the target organ of Pu and Am bioaccumulation at Perna viridis. In the experiment, one of them was biokinetics parameters with CF value of Pu3+ on the gills, digestive glands and organ remains are 7.0 mL.g-1, 8.8 mL.g-1 and 8.0 mL. g-1 respectively. CF value of Pu4+ on the gills, digestive glands and organ remains are 8.8 mL.g-1, 10.4 mL.g-1 and 9.8 mL.g-1 respectively. CF value of Am3+on the gills, digestive glands and organ remains 18 mL.g-1, 22.5 mL.g-1 and 19 mL.g-1 respectively. CF value of Am4+ on the gills, digestive glands and organ remains are 16.5 mL.g-1, 20 mL.g-1 and 17 mL.g-1 respectively. Isotopes of Pu4+ and Am3+ accumulate higher and hold longer in the body compartment of P. viridis than Pu3+ and Am4+. Isotopes of Pu4+ and Am3+ are highest distributed in the body compartment of the digestive glands rather than in the gills. Based on the experiment it is assumed that Perna viridis can be used as a bioindicator."

"Mimicry is a classic example of adaptation through natural selection. The traditional focus of mimicry research has been on defense in animals (protective mimicry), but there is now also a highly developed and rapidly growing body of research on floral mimicry in plants. Being literally rooted to one spot, plants generally have to use food bribes to cajole animals into acting as couriers for their pollen. Plants that lack these food rewards often deploy elaborate color and scent signals in order to mimic food sources, oviposition sites, or mating partners of particular animals, and thereby exploit these animals for the purposes of pollination. This book addresses the question of whether the evolutionary and ecological principles that were developed for protective mimicry in animals also apply to floral mimicry in plants. Visual, olfactory, and tactile signals can all be important in floral mimicry systems. The traditional focus has been on visual cues, but there is increasing evidence that some forms of mimicry, notably sexual and oviposition-site mimicry, are largely based on chemical cues. The molecular basis for these signals, their role in cognitive misclassification of flowers by pollinators, and the implications of these signals for plant speciation are among the topics covered in the book. The chapters of this book are designed to highlight particular systems of floral mimicry and to integrate them into the broader theory of mimicry."

"ABSTRACTTingginya input fosfor sebagai senyawa fosfat ke dalam sistem akuatik mengakibatkan eutrofikasi yang berujung pada terjadinya algae blooming. Input fosfat dalam sistem akuatik ini dicurigai dipengaruhi oleh pelepasan fosfat yang terikat pada besi(III)oksohidroksida ketika tereduksi menjadi besi(II) di sedimen. Oleh karena itu diperlukan pengukuran fosfat dan besi(II) secara simultan. Disebabkan oleh interaksi yang dinamis dari spesies fosfat di sistem alam, maka konsentrasi spesies dapat berubah pada saat penyimpanan sampel, sehingga analisis yang akurat sulit dicapai kecuali dilakukan secara in-situ. Teknik diffusive gradient in thin film (DGT) merupakan salah satu metode pengukuran in-situ yang dikembangkan untuk pengukuran fosfat dan logam. Teknik DGT diteliti menggunakan binding gel campuran TiO2-Chelex. Metode baru ini memperkenalkan penggunakan TiO2 hasil sintesis melalui metode sol-gel sebagai agen pengikat fosfat dan resin Chelex-100 sebagai agen pengikat logam Fe(II). DGT yang terdiri dari diffusive layer dan binding layer diuji kemampuannya dalam menyerap logam labil besi(II) dan fosfat secara terpisah, kemudian diuji homogenitas untuk pengukuran besi(II) dan fosfat secara simultan. DGT dengan binding gel TiO2-Chelex diuji pada sejumlah variasi waktu pengukuran, konsentrasi larutan, dan pH. Hasil analisis menggunakan AAS untuk logam besi dan Spektofotometer UV-Vis untuk fosfat menunjukkan bahwa waktu optimum untuk pengukuran DGT adalah 24 jam. DGT dengan binding gel TiO2-Chelex optimum mengukur fosfat pada larutan dengan pH 5,2 dan pH 6 dan optimum mengukur besi(II) pada pH netral (pH 7). DGT TiO2-Chelex memiliki kapasitas pengukuran 5,86 mg/L untuk fosfat dan 53,41 mg/L untuk logam besi(II).

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ABSTRACTThe high phosphorus as phosphate input into aquatic systems causes eutrophication which leads to the occurrence of algae blooming. Phosphate input in aquatic systems is influenced by the release of suspected phosphate bound to iron(III) when reduced to iron(II) in the sediment. Therefore measurement of phosphate and iron(II) simultaneously is required in the environment. Due to dynamic interaction of phosphate species in the natural system, the concentration of phosphate species can change during sample storage, so that an accurate analysis difficult to achieve unless done in-situ. Diffusive gradients in thin films (DGT) technique is one of the in-situ measurement methods developed for the measurement of phosphate and metals. DGT technique has been studied using gel bindings mixture of TiO2-Chelex. This new method introduces the use of synthesized TiO2 via sol-gel method and resin Chelex-100 as phosphate and Fe(II) binding agents, respectively. DGT composed of diffusive layer and the binding layer metal was tested for their ability to absorb labile iron(II) and phosphate separately, and for homogeneity measurements of iron(II) and phosphate simultaneously. DGT with bindings Chelex gel TiO2 was tested at various time of measurement, solution concentration, and pH. The results of the analysis using AAS for iron and UV-Vis spectrophotometer for phosphate showed that the optimum time for DGT measurement is at 24 hours. Optimum measurement of DGT with bindings gel TiO2-Chelex was reached at pH around 5,2 and 6,0, and neutral (pH 7) for phosphate in solution and iron(II), respectively. TiO2-Chelex DGT measurement capacity was 5,86 mg/L and 53,41 mg/L for phosphate and iron (II), respectively."