Judul: Sintesis Biphasic Calcium Phosphate dari Cangkang Telur Ayam
Abstrak: Biphasic Calcium Phosphate (BCP) are structured from hydroxiapatite (HA) Ca10(PO4)6(OH)2 and β-Tricalcium Phosphate (β-TCP) β-Ca3(PO4)2. HA are stable in difficlut phases when implanted, that’s why modification are needed with the addition of β-TCP which are soluble. The eggshells which undergoes calcination process at 1000 C for 5 hours contains CaO. The creation process of HA and β-TCP with precipitation method called wise drop, this process of creating BCP with the sonication technique with time variable from 5 to 30 minutes and composition variables of 50%:50%, 60%:40%, and 70%:30%. The size of the HA crystal are 55.28 nm, β-TCP are 51.82 nm, and the BCP are range from 43.85 nm – 50.25 nm. Based on the result of FTIR, can gained supporting information of that the samples gained are pure HA and pure β-TCP which are known from the structure complexity OH- and PO43- without the waste of CO32-. According to the EDS results on of the BCP_2a sample spot which are gained randomly, it’s known that on the sample of the BCP there is β-TCP with a Ca/P ratio of 1.46 or close to 1.5.
Keyword: β-Tricalcium Phosphate, biomaterial, Biphasic Calcium Phosphate, hydroxiapatite, sonication.

Judul: Characterization of Biphasic Calcium Phosphate with Ratio of 70/30 Before and After Implanted into Sheep’s Bone
Abstrak: Nowadays, biphasic calcium phosphate is used for biomaterial to cure bone damage. This study focuses only on mixing ratio of 70% mass of hydroxyapatite and 30% mass of tricalcium phosphate with chitosan and acetic acid as the hardening. Pure HA had done by wet precipitation in sintering process at temperature of 900 oC while β-TCP is at temperature of 1000 oC. Mechanical method of BCP is proven to be a non toxic material and could absorb by the mineral body. Implanted BCP was characterized with XRD, FTIR, SEM-EDS and bone characterization with Vickers Hardness. In XRD analysis, the result is adding chitosan makes BCP less accuracy of pure HA and β-TCP. FTIR shows composition of BCP sample with HA, TCP, H2O, AKB, and N-H bending. SEMEDS releases ratio Ca/P of implant in post operation has irregularity caused by interaction with bone that supported by Vickers Hardness number. HV for 1 month of post operation have larger number for both implanted and control bone.
Keyword: β-TCP, HA, BCP

Judul: Peranan Modal Sosial Terhadap Kondisi kerja dan Pendapatan Pekerja Migran Muda Sektor Informal (Studi Kasus Pekerja Migran Desa-Kota Supir Angkot di Bogor).
Abstrak: Sektor pertanian sebagai sektor dengan penyerapan tenaga kerja yang tinggi di desa saat ini tidak lagi dipandang sebagai pilihan pekerjaan bagi pemuda pedesaan. Perubahan aspirasi orangtua dan persepsi pemuda pedesaan terhadap sektor pertanian mendorong mereka untuk melakukan migrasi dan mencari pekerjaan di daerah perkotaan. Sektor informal merupakan pekerjaan yang umumnya dimasuki oleh pemuda perdesaan karena dapat memanfaatkan modal sosial untuk memperoleh jaminan akses, modal, dan keterampilan untuk masuk ke dalam bidang pekerjaan tersebut. Salah satu bidang dalam sektor informal tersebut adalah bidang transportasi dalam kota dan antar kota yang dikenal sebagai “angkot”. Angkutan Kota “Angkot” memiliki flexibilitas jam kerja, modal yang tidak besar untuk bekerja di dalamnya, dan di organisir oleh asosiasi yang tidak terkena regulasi langsung dari pemerintah. Hasil penelitian menunjukan bahwa modal sosial berperan dalam menentukan kondisi kerja supir angkot yang terdiri dari status supir, biaya operasional, dan durasi bekerja. Pada peneltian ditemukan juga komponen variabel kondisi kerja berperan dalam menentukan tingkat pendapatan bersih dan pendapatan tambahan supir angkot.
Keyword: Sektor informal, modal sosial, angkutan kota