Observations on elephant habitat and conservation of elephants in Eritrea

Confined to a small area of about 100 by 50 km, the elephants in Eritrea are one of the northernmost populations in Africa. They are vulnerable because they appear to be genetically isolated and their small number may renders them a non-viable population. During 1997-1999 we visited elephant habitat in the Zoba Gash-Barka in southwest Eritrea to study problems of encroaching human populations on elephant habitat. This situation was described in the preceding article by Hagos Yohannes who is proposing to translocate farmers — with their willing cooperation — from the conflict zone to non-wildlife designated areas. Should such an ambitious plan be too difficult to execute, an alternative solution is being considered

OPTIMIZATION OF A NEUTRON BEAM SHAPING ASSEMBLY DESIGN FOR BNCT AND ITS DOSIMETRY SIMULATION BASED ON MCNPX

This article involves two main objectives of BNCT system. The first goal includes optimization of 30 MeV Cyclotron-based Boron Neutron Capture Therapy (BNCT) beam shaping assembly. The second goal is to calculate the neutron flux and dosimetry system of BNCT in the head and neck soft tissue sarcoma. A series of simulations has been carried out using a Monte Carlo N Particle X program to find out the final composition and configuration of a beam shaping assembly design to moderate the fast neutron flux, which is generated from the thick beryllium target. The final configuration of the beam shaping assembly design includes a 39 cm aluminum moderator, 8.2 cm of lithium fluoride as a fast neutron filter and a 0.5 cm boron carbide as a thermal neutron filter. Bismuth, lead fluoride, and lead were chosen as the aperture, reflector, and gamma shielding, respectively. Epithermal neutron fluxes in the suggested design were 2.83 x 109 n/s cm-2, while other IAEA parameters for BNCT beam shaping assembly design have been satisfied. In the next step, its dosimetry for head and neck soft tissue sarcoma is simulated by varying the concentration of boron compounds in ORNL neck phantom model to obtain the optimal dosimetry results. MCNPX calculation showed that the optimal depth for thermal neutrons was 4.8 cm in tissue phantom with the maximum dose rate found in the GTV on each boron concentration variation. The irradiation time needed for this therapy were less than an hour for each level of boron concentration.Keywords: Optimization, Beam Shaping Assembly, BNCT, Dosimetry, 30 MeV Cyclotron, MCNPX. OPTIMASI DESAIN KOLIMATOR NEUTRON UNTUK SISTEM BNCT DAN UJI DOSIMETRINYA MENGGUNAKAN PROGRAM MCNPX. Telah dilakukan penelitian tentang sistem BNCT yang meliputi dua tahapan simulasi dengan menggunakan program MCNPX yaitu uji simulasi untuk optimasi desain kolimator neutron untuk sistem BNCT berbasis Siklotron 30 MeV dan uji simulasi untuk menghitung fluks neutron dan dosimetri radiasi pada kanker sarkoma jaringan lunak pada leher dan kepala. Tujuan simulasi untuk mendapatkan desain kolimator yang paling optimal dalam memoderasi fluks neutron cepat yang dihasilkan dari sistem target berilium sehingga dapat dihasilkan fluks neutron yang sesuai untuk sistem BNCT. Uji optimasi dilakukan dengan cara memvariasikan bahan dan ketebalan masing-masing komponen dalam kolimator seperi reflektor, moderator, filter neutron cepat, filter neutron thermal, filter radiasi gamma dan lubang keluaran. Desain kolimator yang diperoleh dari hasil optimasi tersusun atas moderator berbahan Al dengan ketebalan 39 cm, filter neutron cepat berbahan LiF2 setebal 8,2 cm, dan filter neutron thermal berbahan B4C setebal 0,5 cm. Untuk reflektor, filter radiasi gamma dan lubang keluaran masing-masing menggunakan bahan PbF2, Pb dan Bi. Fluks neutron epithermal yang dihasilkan dari kolimator yang didesain adalah sebesar 2,83 x 109 n/s cm-2 dan telah memenuhi seluruh parameter fluks neutron yang sesuai untuk sistem BNCT. Selanjutnya uji simulasi dosimetri pada kanker sarkoma jaringan lunak pada leher dan kepala dilakukan dengan cara memvariasikan konsentrasi senyawa boron pada model phantom leher manusia (ORNL). Selanjutnya model phantom tersebut diiradiasi dengan fluks neutron yang berasal dari kolimator yang telah didesain sebelumnya. Hasilnya, fluks neutron thermal mencapai nilai tertinggi pada kedalaman 4,8 cm di dalam model phantom leher ORNL dengan laju dosis tertinggi terletak pada area jaringan kanker. Untuk masing-masing variasi konsentrasi senyawa boron pada model phantom leher ORNL supaya dapat mematikan jaringan kanker, membutukan waktu iradiasi neutron kurang dari satu jam.Kata kunci: Optimasi, Kolimator, BNCT, Dosimetri, Siklotron 30 MeV, MCNP

Implementasi Nilai dan Norma oleh Guru Sosiologi melalui Interaksi Edukatif di Man 1 Pontianak

This research aims to know the implementation of the values and norms by teachers through the interaction of educational sociology in MAN 1 Pontianak. The approach used was qualitative descriptive method approach. This research used the informant as many as 7 people which consisted of 2 teachers of sociology, and 5 students Social Science Department. The results of this research show that the sixth component that includes objectives, materials, methods, tools, resources and evaluation of learning in educational interaction was applied into various forms. On the purpose of the components is done by formulating and delivering learning objectives prior to convey the subject matter. On the learning materials of the components is done by passing a staple lesson material. On the component method is done using the methods vary. On the components of the learning tool is done with the use of books, student worksheets, the LCD when delivering the material. On the component source teachers take resources from the syllabus or the internet and books. On the components of the evaluation done by the oral test, the writings and deeds

Development of Local Allometric Equation to Estimate Total Aboveground Biomass in Papua Tropical Forest

Recently, pantropical allometric equations have been commonly used across the globe to estimate the aboveground biomass of the forests, including in Indonesia. However, in relation to regional differences in diameter, height and wood density, the lack of data measured, particularly from eastern part of Indonesia, may raise the question on accuracy of pantropical allometric in such area. Hence, this paper examines the differences of local allometric equations of Papua Island with equations developed by Chave and his research groups. Measurements of biomass in this study were conducted directly based on weighing and destructive samplings. Results show that the most appropriate local equation to estimate total aboveground biomass in Papua tropical forest is Log(TAGB) = -0.267 + 2.23 Log(DBH) +0.649 Log(WD) (CF=1.013; VIF=1.6; R2= 95%; R2-adj= 95.1%; RMSE= 0.149; P<0.001). This equation is also a better option in comparison to those of previously published pantropical equations with only 6.47% average deviation and 5.37 points of relative bias. This finding implies that the locally developed equation should be a better option to produce more accurate site specific total aboveground biomass estimation

Jenis dan Status Konservasi Ikan Hiu yang Tertangkap di Tempat Pelelangan Ikan (TPI) Labuan Bajo, Manggarai Barat, Flores

The study aimed to determine the types of sharks are caught, sold and conservation status in the fish auction place (TPI) Labuan Bajo, West Manggarai, Flores, East Nusa Tenggara have been conducted in February and March 2014 in Labuan Bajo. The research method was the survey method and used Market Survey sampling techniques and identification by Rapid Assessment method. Descriptively analyzed data, displayed in the form of narration and a table. Based on the results of the study, found 114 individual sharks, 55 individual males, 59 females were classified into three orders, namely Orectolobiformes, Lamniformes, and Carcharhiniformes; 4 families that Carcharhinidae, Odontaspididae, Rhynchobatidae, and Ginglymostomatidae; 5 genera namely Carcharhinus, Triaenodon, Rhyncobatus, Prionace, and Rhizoprionodon and 9 types of sharks that Carcharhinus melanopterus, Triaenodon obesus, Carcharhinus limbatus, Carcharhinus taurus, Carcharhinus amblyrhynchos, Rhynchobatus Australiae, Prionace glauca, Rhizoprionodon acutus, and Nebrius ferrugineus. Based on the state of conservation, shark found in Labuan Bajo TPI classified Vulnerable and Near Threatened, the dominant type of shark found is Carcharhinus melanopterus (91 fishes) while the least was found is Rhynchobatus Australiae, Prionace glauca, Rhizoprionodon acutus, and Nebrius ferrugineus (each 1 individual)

Improving Students' Narrative Text Writing By Using West Kalimantan Folklore

This research was designed to improve students' writing narrative text by using West Kalimantan folklore. This research used a classroom action research. The sample of this research was XI MIA 1 students of SMA Negeri 2 Pontianak which consisted of 40 students. Field note, observation checklist, and students' writing test were used as the tools of data collecting. The writer applied 2 cycles in this research. The process of cycle 1 was needed to improve. The writer and the English teacher considered to take the cycle 2. The cycle 2 was successful because each students improved their score in writing. The writer concluded the good process brings good score. The use of West Kalimantan folklore was able to improve the students' writing narrative text

Sentra Kerajinan Tenun Songket Sumatera di Pekanbaru dengan Pendekatan Arsitektur Postmodern

As a Malay traditional craft, Sumatera Songket is known it's high culture value. With varioud of pattern, the songket has a peculiarity interesting to tourists. Therefore a facility to accommodate songket is needed to conserve and to provide information to public, in order to let them to know and learn decorative of pattern and the process of making the songket. The facility is a center of craft industrial area which produce songket. With the Postmodern Architecture approach, the concept of this center is Khazanah Songket Melayu which is defined as a high value of the culture. Through the neo-vernacularism design method, it is applied on zoning, the massing, the landscaping, and facade. This production center area has applied Songket pattern arrangement, the landscape is in accordance to the mass. While the mass has designed with decorative pattern ornament. The pattern of mangosteen, and local decorative ornament are applied to building facade in neo-vernacularism design