Menstrual Cycle Irregularity and Body Mass Index Among Secondary School Students in Sragen, Central Java

BACKGROUND: The Indonesian Health Survey in 2010 reported that 68.3% of women aged 10-59 years old had a regular menstrual cycle in the past one year. Approximately 13.7% of the affected women experienced problem associated with irregular menstrual cycle. Irregular menstrual cycle may cause anxiety, heighten emotional sensitivity, and disturb daily activities in the affected women. Irregular menstrual cycle occurs due to imbalanced sexual hormone. This hormonal imbalance might be worsened by poor nutritional status. This study aimed to estimate the association between irregular menstrual cycle and body mass index. SUBJECT AND METHODS: This was a cross sectional study conducted in Sragen, Central Java. A sample of class IX secondary school (MTs) students in Kalijambe, Sragen, was selected at random for this study. The dependent variable was the menstrual cycle irregularity in the past 3 months. It was measured by a questionnaire. The independent variable was body mass index. The body weight was measured by a weight scale. The body height was measured by micro-toise. The association between study variables was estimated by Spearman correlation coefficient. RESULTS: Fifty percent of the sample had normal body weight, 43.8% were underweight, 6.3% were obese. As much as 12.5% of them had irregular menstrual cycle. There was a very weak and statistically non-significant correlation between body mass index and menstrual cycle irregularity (r=0.08; p=0.183). CONCLUSION: There was a very weak and statistically non-significant correlation between body mass index and menstrual cycle regularity. Keywords: menstrual cycle, regularity, body mass inde

Matriks Invers Moore-penrose Dalam Penyelesaian Sistem Persamaan Linier

In this paper we define and study about The Moore Penrose Inverse of any matrices under the rank. We apply our result to study of Solution Linear Equation Siste

Respon Kalus Beberapa Varietas Padi (Oryza Sativa L.) pada Kondisi Cekaman Salinitas (NaCl) secara In Vitro

Penelitian ini bertujuan untuk mengetahui respon kalus padi (varietas Ciherang, Sembada 168, dan Banyuasin) pada tahap induksi kalus terhadap masing-masing faktor seleksi. Metode yang digunakan pada penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan pola faktorial 2 faktor. Faktor pertama adalah 3 varietas terdiri dari Varietas Ciherang, Sembada 168, dan Banyuasin. Faktor kedua adalah 4 konsentrasi NaCl, yaitu 0 mM, 50 mM, 150 mM, dan 250 mM. Hasil Uji ANOVA menunjukkan bahwa Interaksi antara varietas dan konsentrasi NaCl memberikan pengaruh terhadap respon kalus beberapa varietas Padi (Oryza sativa L.) pada tahap induksi kalus, meliputi pertambahan diameter dan massa kalus. Kalus bertahan hidup hingga konsentrasi NaCl paling tinggi (250 mM) dengan skoring morfologi yang semakin kecil pada konsentrasi NaCl yang semakin tingg

Model Manajemen Kapasitas Produksi Tomat pada Sentradi Kabupaten Garut

Tomat merupakan salah satu komoditas yang harganya selalu berubah-ubah selain cabai. Jika cabai pernah mengalami harga yang dikatakan paling tinggi justru untuk tomat pernah mengalami harga terendah sampai para petani lebih memilih untuk tidak melakukan pemanenan karena biaya operasional untuk memanen lebih tinggi dibandingkan dengan harga yang akan mereka peroleh. Hal tersebut dikarenakan produksi tomat yang sangat melimpah sedangkan tidak diimbangi dengan permintaan di pasaran. Penelitian ini bertujuan untuk merancang model manajemen kapasitas produksi pada komoditas tomat dalam upaya memenuhi permintaan pasar di Kabupaten Garut dengan pendekatan dinamika sistem. Kabupaten Garut sebagai sentra produksi tomat Propinsi Jawa Barat dengan fokus penanaman Kecamatan Cikajang dan Surupan, menjadi wilayah kerja penelitian ini. Identifikasi kebutuhan untuk model manajemen kapasitas produksi dilakukan melalui studi pustaka dan wawancara dengan pakar dari pemangku kepentingan, yaitu praktisi dan pemangku kebijakan yang terlibat dalam prosedur penyediaan input, produksi, serta pemasaran. Data yang dikumpulkan berupa data primer dan data sekunder.Formulasi model dilakukan dengan softwareVeneta Simulation(Vensim DSS), yang dilanjutkan dengan simulasi. Hasil Penelitian Menunjukan bahwa tomat yang dihasilkan petani di sentra produksi Kabupaten Garut untuk pasokan ke pasar tradisional dan Industri belum sepenuhnya terpenuhi sesuai dengan permintaan yang dinginkan. Kata Kunci :Dinamika Sistem Kapasitas Produki Rantai Paso

Accretion and destruction of planetesimals in turbulent disks

We study the conditions for collisions between planetesimals to be accretional or disruptive in turbulent disks, through analytical arguments based on fluid dynamical simulations and orbital integrations. In turbulent disks, the velocity dispersion of planetesimals is pumped up by random gravitational perturbations from density fluctuations of the disk gas. When the velocity dispersion is larger than the planetesimals' surface escape velocity, collisions between planetesimals do not result in accretion, and may even lead to their destruction. In disks with a surface density equal to that of the ``minimum mass solar nebula'' and with nominal MRI turbulence, we find that accretion proceeds only for planetesimals with sizes above $\sim 300$ km at 1AU and $\sim 1000$ km at 5AU. We find that accretion is facilitated in disks with smaller masses. However, at 5AU and for nominal turbulence strength, km-sized planetesimals are in a highly erosive regime even for a disk mass as small as a fraction of the mass of Jupiter. The existence of giant planets implies that either turbulence was weaker than calculated by standard MRI models or some mechanism was capable of producing Ceres-mass planetesimals in very short timescales. In any case, our results show that in the presence of turbulence planetesimal accretion is most difficult in massive disks and at large orbital distances.Comment: 15 pages, 5 figures, accepted for publication in Ap

Toward a Deterministic Model of Planetary Formation IV: Effects of Type-I Migration

In a further development of a deterministic planet-formation model (Ida & Lin 2004), we consider the effect of type-I migration of protoplanetary embryos due to their tidal interaction with their nascent disks. During the early embedded phase of protostellar disks, although embryos rapidly emerge in regions interior to the ice line, uninhibited type-I migration leads to their efficient self-clearing. But, embryos continue to form from residual planetesimals at increasingly large radii, repeatedly migrate inward, and provide a main channel of heavy element accretion onto their host stars. During the advanced stages of disk evolution (a few Myr), the gas surface density declines to values comparable to or smaller than that of the minimum mass nebula model and type-I migration is no longer an effective disruption mechanism for mars-mass embryos. Over wide ranges of initial disk surface densities and type-I migration efficiency, the surviving population of embryos interior to the ice line has a total mass several times that of the Earth. With this reservoir, there is an adequate inventory of residual embryos to subsequently assemble into rocky planets similar to those around the Sun. But, the onset of efficient gas accretion requires the emergence and retention of cores, more massive than a few M_earth, prior to the severe depletion of the disk gas. The formation probability of gas giant planets and hence the predicted mass and semimajor axis distributions of extrasolar gas giants are sensitively determined by the strength of type-I migration. We suggest that the observed fraction of solar-type stars with gas giant planets can be reproduced only if the actual type-I migration time scale is an order of magnitude longer than that deduced from linear theories.Comment: 32 pages, 8 figures, 1 table, accepted for publication in Ap