Estimates of Genetic and Phenotypic Trends of Growth Traits in Bali Cattle

The aim of this study was to estimate genetic and phenotypic trends for growth traits including birth (BW), weaning (WW) and yearling weight (YW) in Bali cattle. The number of cattle used to determine growth traits of BW, WW, and YW were 235, 215, and 178 heads, respectively. Estimation of breeding value, phenotypic and genetic correlation were calculated by Restricted Maximum Likelihood and General Linier Model (GLM) procedures, respectively. Genetic trends analysis was performed using the regression mean breeding values on birth year. Phenotypic and genetic correlation among BW and WW were 0.10 and 0.08 respectively and 0.90 and 0.70 for WW and YW respectively. The phenotypic trends for traits of birth and weaning weight were constant, whereas yearling weight was fluctuating from 2000 to 2008. Likewise, in the case of genetic trends, the birth and weaning weight were constant from 2000 to 2008 except for WW in 2005, whereas the genetic trends for yearling weight showed a fluctuation of wide range. According to the breeding value estimated for all traits, the best was the sire No. 0565, whose breeding value for BW, WW and YW were +0.07, +2.79, and +10.25 kg, respectively higher than the mean value of the population. The genetic trends showed that there have been a significant and positive genetic improvement in all growth traits and indicate that selection would be effective. Genetic correlation between WW and YW was high (0.70) which indicates that the selection on weaning weight might also increase yearling weight in Bali cattle

Broad-band Modeling of GRB Afterglows

Observations of GRB afterglows ranging from radio to X-ray frequencies generate large data sets. Careful analysis of these broad-band data can give us insight into the nature of the GRB progenitor population by yielding such information like the total energy of the burst, the geometry of the fireball and the type of environment into which the GRB explodes. We illustrate, by example, how global, self-consistent fits are a robust approach for characterizing the afterglow emission. This approach allows a relatively simple comparison of different models and a way to determine the strengths and weaknesses of these models, since all are treated self-consistently. Here we quantify the main differences between the broad-band, self-consistent approach and the traditional approach, using GRB000301C and GRB970508 as test cases.Comment: Appears in "Gamma-Ray Bursts in the Afterglow Era" proceedings of the Roma 2000 GRB Workshop; 3 pages; 2 figure

Power Density Spectra of Gamma-Ray Bursts in the Internal Shock Model

We simulate Gamma-Ray Bursts arising from internal shocks in relativistic winds, calculate their power density spectrum (PDS), and identify the factors to which the PDS is most sensitive: the wind ejection features, which determine the wind dynamics and its optical thickness, and the energy release parameters, which give the pulse 50-300 keV radiative efficiency. For certain combinations of ejection features and wind parameters the resulting PDS exhibits the features observed in real bursts. We found that the upper limit on the efficiency of conversion of wind kinetic energy into 50-300 keV photons is $\sim$ 1%. Winds with a modulated Lorentz factor distribution of the ejecta yield PDSs in accord with current observations and have efficiencies closer to $10^{-3}$, while winds with a random, uniform Lorentz factor ejection must be optically thick to the short duration pulses to produce correct PDSs, and have an overall efficiency around $10^{-4}$.Comment: 6 pages, 4 figures, Latex, submitted to The Astrophysical Journal (05/04/99

On The Synchrotron Self-Compton Emission from Relativistic Shocks and Its Implications for Gamma-Ray Burst Afterglows

We consider the effects of inverse Compton scattering of synchrotron photons from relativistic electrons in GRB afterglows. We compute the spectrum of the inverse Compton emission and find that it can dominate the total cooling rate of the afterglow for several months or even years after the initial explosion. We demonstrate that the presence of strong inverse Compton cooling can be deduced from the effect it has on the time-evolution of the cooling break in the synchrotron spectral component, and therefore on the optical and X-ray afterglow lightcurves. We then show how the physical interpretation of the observed characteristics of the synchrotron spectrum must be modified to take into consideration this extra source of cooling, and give a revised prescription for computing physical parameters characterizing the expanding shock wave from the observed quantities. We find that for a given set of observables (synchrotron break frequencies and fluxes) there is either no consistent physical interpretation or two of them. Finally we discuss the prospects of directly detecting the inverse Compton emission with Chandra. We argue that such a detection is possible for GRBs exploding in a reasonably dense (n>1 cm^-3) medium.Comment: 21 pages, ApJ submitte

GRB990123, The Optical Flash and The Fireball Model

We compare the ongoing observations of the remarkable burst GRB990123, the mother of all bursts, with the predictions of the afterglow theory. We show that the observations agree with the recent prediction that a reverse shock propagating into the ejecta would produce a very strong prompt optical flash. This reverse shock has also produced the 8.46GHz radio signal, observed after one day. The forward shock, which propagates into the ISM is the origin of the classical afterglow. It has produced the prompt X-ray signal as well as the late optical and IR emission. It would most likely produce a radio emission within the next few weeks. The observations suggest that the initial Lorentz factor of the ejecta was $\sim 200$. Within factors of order unity, this crude model explains all current observations of GRB990123.Comment: 14 pages including 2 figure

Sum rules for correlation functions of ionic mixtures in arbitrary dimension d≥2d\geq 2

The correlations in classical multi-component ionic mixtures with spatial dimension $d\geq 2$ are studied by using a restricted grand-canonical ensemble and the associated hierarchy equations for the correlation functions. Sum rules for the first few moments of the two-particle correlation function are derived and their dependence on $d$ is established. By varying $d$ continuously near $d=2$ it is shown how the sum rules for the two-dimensional mixture are related to those for mixtures at higher $d$.Comment: 19 page

Penerapan Model Pembelajaran Koperatif Tipe Stad (Student Teams Achievement Divisions) Untuk Peningkatkan Belajar Siswa

Adanya aktivitas guru yang tetap dalam pengajaran, aktivitas siswa yang cenderung bersikap acuh,diam tidak aktif dan sesekali menguap serta hasil belajar yang kurang memuaskan itu semua terlihat di beberapa kelas di SDN Sumolawang Mojokerto. Hal inilah yang mendorong peneliti untuk melaksanakan  suatu Penelitian Tindakan Kelas. Penelitian Tindakan kelas bertujuan untuk meningkatkan aktivitas guru  dan siswa agar lebih aktif dinamis serta yang lebih penting untuk meningkatkan hasil belajar siswa dan meningkatkan mutu pendidikan di SDN Sumolawang Mojokerto. Untuk itu diperlukanlah suatu model pembelajaran sebagai solusi untuk mengatasi permasalahan tersebut maka dipilihlah Pembelajaran Kooperatif Tipe STAD. Pada Pembelajaran Kooperatif tipe STAD ini siswa dibagi menjadi beberapa kelompok,yang masing – masing kelompok beranggotakan 4 – 5 orang. Pada pembelajaran ini siswa dalam kelompok – kelompok tersebut dibimbing dan diarahkan guru untuk berdiskusi dan mengutarakan pendapat secara terbuka serta mempresentasikan hasil diskusinya ke depan kelas. Di samping itu guru juga memberikan kuis bagi siswa. Guru akan memberikan penghargaan pada siswa dan kelompok yang berprestasi dalam pembelajaran itu. Pada pembelajaran  kooperatif ini ada intensitas komunikasi yang intensif antara guru dengan siswa dan antara siswa dengan siswa. Hasil dari Penelitian Tindakan Kelas ini dapat terlihat setelah melalui tiga (3) siklus pembelajaran, hal ini terbukti dengan adanya peningkatan indikator pada aktivitas guru,siswa dan hasil belajar siswa dari perbandingan data temuan awal, siklus I sampai siklus III. Kata  Kunci  :  Pembelajaran  kooperatif  STAD, Pembelajaran  Tematik, Hasil  Belajar &nbsp

The Napa Change Model: an Approach to Ease the Organizational Change

Perubahan adalah suatu keharusan dalam sebuah organisasi dalam mempertahankan eksistensinya. Perubahan organisasi dapat berupa Perubahan yang sistemik ataupun struktural, dan dapat dilakukan sendiri oleh organisasi tersebut maupun dengan bantuan konsultan. Dalam melakukan Perubahan, dibutuhkan keberanian dari dalam diri organisasi untuk bertransformasi dari keadaan saat ini ke keadaan ideal yang diharapkan. Oleh karena itu, organisasi memerlukan sebuah model Perubahan yang dapat dijadikan sebagai acuan dalam mengimplementasikan Perubahannya. The NAPA Change Model merupakan model Perubahan yang diajukan oleh penulis sebagai sebuah pendekatan yang dapat diadopsi agar Perubahan dapat berjalan dengan baik. Model ini meliputi empat fase, yaitu fase pengenalan kebutuhan (Need Urgency), fase penilaian dan analisis (Assessment and Analysis), fase perencanaan (Planning), dan fase pelaksanaan (Action). Fase pengenalan kebutuhan dilakukan dengan cara membandingkan antara keadaan organisasi saat ini dengan keadaan ideal yang diharapkan oleh organisasi. Fase Penilaian dan analisis meliputi beberapa tahap analisis, yaitu analisis PEST, analisis SWOT, dan analisis Force Field. Fase perencanaan merupakan tahapan pengembangan strategi dan rencana aksi organisasi untuk mengelola transisi organisasi dari keadaan saat ini ke keadaan idealnya. Fase pelaksanaan merupakan fase dimana organisasi mulai melakukan Perubahan berdasarkan desain yang sudah dibuat dalam fase sebelumnya. Kelebihan model ini adalah bahwa model ini menawarkan fleksibilitas kepada agen Perubahan ataupun pemimpin Perubahan untuk dapat melakukan refleksi, pengambilan kesimpulan, dan pengambilan keputusan selama proses pelaksanaan keempat fase yang sudah dijelaskan diatas