Judul: Sistem filtrasi akuarium air laut untuk pengendalian senyawa nitrogen dalam air
Abstrak: Sistem filtrasi merupakan bagian terpenting dari sistem akuarium air laut, fungsinya untuk tetap menjaga kualitas air laut yang digunakan sesuai dengan yang dibutuhkan. Alat yang digunakan untuk melakukan proses filtrasi disebut dengan filter atau sump.
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Judul: Teknik Perbaikan Filter Fisik Dan Filter Kimia Pada Sistem Resirkulasi Pembenlhan Ikan Patin (Pangasius Hipophtlwlmus)
Abstrak: Pembenihan ikan Patin dalam aquarium bertujuan untuk meminimumkan tingkat kematian memerlukan pengontrolan terhadap parameter-parameter yang berpengaruh terhadap kondisi ikan.Parameter tersebut antam lain kandungan pH., N03, N02, DO,dan NH3. Kelima faktor kimia tersebut sangat mempengaruhi kualitas air. Air sebagai lingkungan abiotik diresirkulasi secam tertutup. Sistem resirkulasi ini dibagi kedalam empat bagian yaitu bak pemeliharaan, filter mekanik, filter biologi, dan filter kimia.Filter mekanik dan filter biologi dijadikan satu bagian dengan susunan dari atas kebawah : ijuk, busa (filter mekanik), pasir, kerikil,dan zeolit (filter biologi). Perbandingan susunan masing-masing 2:1:3:2:LKetinggian filtmsi sebesar duapertiga dari total tinggi bak saringan. Kerusakan filter mekanik diindikasikan dengan meluapnya air dibak saringan pada tenggang waktu tertentu, Hal ini disebabkan oleh menumpuknya kotoranJpartikel organik berukuran besar sehingga menyumbat filter. Waktu yang tepat untuk mengganti filter tersebut diduga dengan menggunakan rumus Inhibited Population Model dengan mengetahui terlebih dulu nilai faktor retardasi (y) dan koefisien u. Tanaman kangkung air digunakan sebagai filter kimia yang berfungsi untuk mereduksi konsentmsi nitrat hasil dari biofilter. Diperlukan panjang akar rata-rata kangkung yang optimal supaya mencapai konsentrasi nitrat yang diijinkan. Reduksi konsentrasi nitrat dinyatakan dalam persen. Koefisien u dan y pada persamaan Inhibited PopUlation Model dipecahkan terlebih dulu menggunakan rumus Least Square Methode, Newton Raphson, Jacobian Matrik, dan Gaus Jordan. Berdasarkan hasil penelitian diperoleh kualitas air yang ideal bagi pembenihan ikan patiCl yaitu pH = 6.91, NH3 = 0.626 ppm, DO = 5.65 ppm, dan NO) = 0.632 ppm, N02 = 0.52 ppm. Pada pendugaan wak'tu yang tepat untuk penggantian filter diperoleh nilai faktor retardasi = 0.048 dan koefisien a = 2 Sedangkan panjang akar rata-rata kaTIgiwng yang optimum dapat riiperoieh menggunakan software Borland Delphi 6.0 dengan input konsentrasi nitrat awal dan konsentrasi nitrat yang diijinkan, koefisien a = 2 dan y = 0.2.
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Judul: Studies on growth spurt and aging in higher primates
Abstrak: single measurement that best defines the health and nutritional status of children, just as it provides an indirect measurement of the quality of life of an entire population. The pattern of human growth reflects the biocultural evolution of our species. The human pattern of growth and development (ontogeny) appears to differ markedly from patterns of ontogeny in other primate species. Three studies are reported here which deal to the growth and development of human and chimpanzee (Pan troglodytes). These three studies allow us to contrast the phenomena of adolescence growth spurt and female elderly bone loss in chimpanzee and human as chimpanzee is the closest species to humans within extant nonhuman primates. In the first, a cross-sectional study of growth of the body size and somatotype of 363 Javanese girls and 299 Javanese boys aged 4 to 20 years from Magelang Regency, Indonesia was described. In the second, cross-sectional and longitudinal studies in the growth of chimpanzee second metacarpal bone linear dimensions from individuals aged 0 to 43.6 years were used for comparison. While in the third, cross-sectional and longitudinal studies in the growth of chimpanzee body size (body mass and anterior trunk length) and second metacarpal bone mineral content were derived. In measuring the second metacarpal dimensions and mineral content, a total of 568 radiographs of chimpanzee's proximodistal left hands were used. They were taken from 68 females and 49 males aged 0 to 43.62 years old. We applied an image analysis system, Scion Image Release Alpha 4.0.3.2 software for Windows to measure bone linear dimensions and bone mineral content. Humans present complex and sinuous growth curves for both body weight and height. A clear growth spurt could be demonstrated by cross-sectional analysis in our girl subjects at around aged 11.5 years and in our boy subjects at around aged 12.5 years. In longitudinal series, not in cross-sectional, several representative chimpanzees of both sexes showed a pre-adult growth spurt on the body sizes, bone dimensions and bone mineral content. They ranged at age 4.5 to 8.5 years. This underscore the fact that adolescent growth spurt in linear dimension was not a universal feature of anthropoid primate ontogeny. Bone loss is a well established characteristic of human female aging. Based on crosssectional analyses the sequential decline of bone mass in female chimpanzee may be said to be genuine. On the other hand, we found in adulthood through elderly, male chimpanzees show a longer plateau than female chimpanzee, that is, bone mineral content is maintained in male.
Keyword: Javanese children, growth spurt, chimpanzee, second metacarpal bone, bone loss, Higher Primates