Judul: Interaksi Orangutan (Pongo pygmaeus wurmbii) Betina dengan Individu Lain dan Hubungannya Profil Metabolit Glukokortikoid di Stasiun Penelitian Orangutan Tuanan, Kalimantan Tengah
Abstrak: Bornean Orangutans (Pongo pygmaeus wurmbii) is one of the endemic primates the status of endangered according to the IUCN and was listed on Appendix I of CITES. Population declined caused by destruction, habitat decreased, and illegal arrests. The research of orangutans had been conducted mainly in primary forest, but still slightly research on of social behavior in orangutans located in secondary forest. Stasiun Penelitian Orangutan Tuanan (SPOT) is the orangutans habitat were included in the category of secondary forest and having a degraded was quite high so that easier to fire during the dry season. Orangutans is a frugivore animals and highly sensitive to the changes of habitat conditions. Habitat destruction massively affects the changes of social behavior of orangutans. Reduced range area increase in the occasion encounter between individuals increasingly higher, whereas the orangutans are a semisolitary social system. Social behavior of orangutans is only visible when the parenting and social reproduction. The level of stress hormones in non-primate animals highly influenced by environmental factors such as climate, the presence of other individuals, reproductive status and social status. At the time of social relationships, there will be increase in reproductive interactions with other individuals. The female of orangutans very considerate of the individual status of the male, who became her partner. The differences of male bimaturism morphological making a competition increasingly higher between flanged adult males and unflanged to get a female reproductive. It will effects a female to feels threatened. The threats continuously, will effects of excessive stress. Stress is a physiological response of the body to adjust the environmental changes or threats. The detection method of stress hormone levels in this study was to used a non-invansif with feces collected each morning by homogenising all the layers of feces. Furthermore, another method used was the method of recording behavior that is focal animal sampling which is done by instantaneous every single individual within 5-10 days of the observation period. The recording of social reproduction data was by ad libitum sampling. The recording of female individuals reactions data comprises the number of long call and chance encounter. Data of chance encounters comprises an encounter intervals between individual a female reproductive and non-reproductive with female individuals are related, individual of flanged adult males, individual of unflanged adult males. In addition, female individuals encounter distance data in the pairwise relations (consortship) with individual adult males males unflanged. The intervals used were <2m, 2-10m and 10-50m and recording of the sexual copulation behavior. Behavioral data were correlated with levels of glucocorticoid hormones as indicators of stress hormones. v Based on observations it can be expressed that the difference of reproductive status and social status on the females individual affects the response female individuals towards the number of long call and distance encounter with another individual. The response of female reproductive nullipara and nonreproductive long call pairwise relations gives a respond to ignore Kondor (44.4%), Kerry (38.9%), Milo and Mindy (5.7%). Individual response of female reproductive nullipara and non-reproductive againts the number of long call in pairwise relations response to ignore Kondor (44.4%), Kerry
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Judul: Daily Activities and Food Selection Bornean Orangutan (Pongo pygmaeus) at Taru Jurug Animal Park, Surakarta City
Abstrak: Orangutan Kalimantan atau Bornean Orangutan (Pongo pygmaeus) merupakan satwa endemik yang hanya dapat dijumpai di Pulau Kalimantan dan tergolong ke dalam ordo Primata serta famili Hominidae. Pada umumnya, aktivitas harian yang biasa dilakukan orangutan diantaranya ialah makan, bergerak, istirahat, dan sosial. Orangutan sebagai satwa yang termasuk frugivor cenderung memiliki preferensi pakan pada buah. Penelitian ini bertujuan menganalisis aktivitas harian, preferensi pakan, serta palatabilitas pakan yang dikonsumsi orangutan kalimantan di Taman Satwa Taru Jurug, Kota Surakarta. Subjek yang diamati ialah dua individu orangutan berjenis kelamin betina dan jantan. Metode yang digunakan ialah focal animal sampling, penyajian pakan berupa cafetaria, penimbangan bobot konsumsi pakan. Hasil pengamatan menunjukkan bahwa lokomosi dan istirahat menjadi aktivitas yang dominan dilakukan oleh individu tori (♀) dan didi (♂). Apel, pear, pisang dan tempe rebus menjadi preferensi pakan dari kedua individu tersebut dengan bobot konsumsi pakan yang tidak berbeda signifikan berdasarkan perhitungan uji t terhadap jenis kelamin dengan jumlah bobot konsumsi pakan., Bornean Orangutan (Pongo pygmaeus) is an endemic animal that can only be found on the island of Borneo and belongs to the order Primate and family Hominidae. Orangutans' daily activities generally include eating, moving, resting, and social activity. Orangutans, as frugivores, tend to have a preference for food on fruit. This study aims to analyze the daily activities, feed preferences, and palatability of the feed consumed by the Bornean orangutan at Taru Jurug Animal Park, Surakarta City. The subjects observed were two male and female orangutans. The method used was focal animal sampling, serving food in the form of a cafeteria, and weighing feed consumption. The results showed that locomotion and resting were the dominant activities carried out by tori (♀) and didi (♂). Apples, pears, bananas, and boiled tempeh became the feed preferences of the two individuals with feed consumption weights that were not significantly different based on the calculation of the t-test for sex with the total weight of feed consumption.
Keyword: endemic, focal animal sampling, palatability, preference, Taru Jurug Animal Park

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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