Judul: aEstimasi willingness to pay (WTP) pengunjung terhadap ruang terbuka hijau di Kota Meda (Studi kasus: Hutan Kota Taman Beringin)
Abstrak: The use of urban land for economy activities are increasing along with the increase of population growth number which causes the change of open green spaces. The study of the estimation Willingness to Pay (WTP) for green open space is needed to green open space management in the future. The objectives of this study are to identify the perception of visitors, their WTP, and influencing factors of WTP consideration. The method used in this study are descriptive analysis, application of Contingent Valuation Methods (CVM), and multiple linear regression analysis. The result shows that the number of WTP is around IDR5,681.82 per person per visit or IDR290,340,909.1 per year, which influencing factors are number of income, number of burden, dummy of sanitation and dummy of freshness
Keyword: Willingness to Pay, Medan City, Hutan Kota Taman Beringin, green open space, estimation

Judul: The Economic Value of Green Open Space in Medan Based on Type of Land Use
Abstrak: Kota Medan merupakan ibu kota Provinsi Sumatera Utara memiliki banyak permasalahan lingkungan, sehingga membutuhkan keberadaan ruang terbuka hijau yang dapat memperbaiki iklim mikro. Suhu dan kelembaban udara sebagai bagian dari unsur iklim mikro mempengaruhi tingkat kenyamanan yang pada akhirnya akan mempengaruhi kualitas masyarakat. Nilai ekonomi hutan kota perlu dihitung secara kuantitatif agar keberadaannya dianggap sebagai kebutuhan kota. Penelitian ini bertujuan untuk mengestimasi nilai ekonomi RTH berdasarkan faktor biotik, fisik, dan sosial pada kawasan permukiman, kawasan bisnis dan perkantoran, serta kawasan industri di Kota Medan. Penelitian dilakukan di ruang terbuka hijau Cadika, Beringin, dan Maharani. Data penelitian dikumpulkan selama Desember 2020-Februari 2021. Hasil penelitian menunjukkan secara kuantitatif melalui nilai THI RTH masuk dalam kategori tidak nyaman (THI>26) dan sejalan dengan persepsi responden masyarakat secara kualitatif bahwa hutan kota tidak nyaman. Rata-rata WTP responden pengunjung pada ketiga RTH tersebut, yaitu berkisar antara Rp5.800 sampai dengan Rp10.833 per kunjungan. Total WTP dari responden pengunjung pada ketiga RTH senilai Rp. 29.268.000/tahun. Berdasarkan analisis harga hedonis, semakin dekat 1 meter dengan RTH akan meningkatkan harga properti yang berbeda di setiap RTH., Medan City is the capital of North Sumatra Province has many environmental problems, so it requires the existence of green open space could ameliorate microclimate. Air temperature and humidity as part of the microclimate element affect the level of comfort that will ultimately affect quality of the society. It is necessary to quantitatively calculate the economic value of the urban forests so that their existence is considered a need for the city. This study aims to estimate the economic value of green open space based on biotic, physical, and social factors in residential areas, business and office areas, and industrial areas in Medan City. The research was conducted in Cadika, Beringin, and Maharani green open spaces. The research data was collected during December 2020-February 2021. The results showed that quantitatively, through the THI value, the green open space was in the uncomfortable category (THI>26) and line with the community respondents perception qualitatively that the urban forest was uncomfortable. The average WTP of visitor respondents in the three green open spaces, which ranged from Rp. 5,800 to Rp. 10,833 per visit. The total WTP of the visitor respondents in the three green open spaces is Rp. 29,268,000/year. Based on hedonic price analysis, getting 1 meter closer to green space will increase property prices that are different for each green open space.
Keyword: economic value, green open space, Medan City, willingness to pay

Judul: Influenza Specific Immunoglobulin Y Purification from Egg Yolk with Sodium Chloride Precipitation Method
Abstrak: Imunoglobulin Yolk (IgY) yang terdapat dalam kuning telur telah banyak dimanfaatkan untuk imunoterapi dan imunodiagnostik. Salah satu kendala dalam pemurnian IgY dari kuning telur adalah pemisahan Ig dengan lemak, sehingga teknik pemurnian Ig selalu berkembang. Penelitian ini bertujuan untuk melakukan pemurnian IgY dari kuning telur dengan metode pengendapan menggunakan sodium chloride (NaCl) serta melakukan karakterisasi IgY spesifik influenza. Sodium chloride dipilih karena bahan kimia ini relatif murah, ramah lingkungan, dan tidak merusak imunoaktivitas IgY. Kuning telur yang digunakan dalam penelitian ini berasal dari telur ayam layer yang divaksinasi dengan vaksin influenza Flubio® yang berisi virus Influenza A/H3N2, A/H1N1 dan B/Washington. Pemurnian IgY hanya dilakukan pada kuning telur yang mengandung antibodi spesifik influenza. Deteksi keberadaan antibodi spesifik influenza ditentukan dengan uji agar gel presipitasi (AGP) dan metode enzyme linked immunosorbent assay (ELISA). Konsentrasi IgY hasil pemurnian dihitung dengan spektrofotometer dan karakterisasi protein dilakukan dengan metode Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Konsentrasi protein dari hasil pemurnian IgY memiliki nilai rata – rata 50,403 mg/mL. Hasil SDS-PAGE menunjukkan enam pita protein, yaitu struktur IgY utuh (174,63 kDa), Apoprotein-LDL (129,77 kDa), rantai berat IgY (66,54 kDa), Fab ( 47,65 kDa), rantai ringan IgY (21,85 kDa), dan β-livetin (36,74 kDa). IgY hasil pemurnian masih dapat berikatan dengan antigen influenza berdasarkan uji ELISA. Hasil penelitian ini menunjukkan bahwa pemurnian IgY menggunakan metode pengendapan NaCl dapat memurnikan IgY dengan struktur utuh, meskipun masih ada dua protein tidak spesifik hasil pemurnian. IgY yang dapat berikatan dengan antigen influenza mengindikasikan prospek pemanfaatannya untuk pencegahan influenza dan imunodiagnostik., Yolk immunoglobulin (IgY) contained in egg yolk has been widely used for immunotherapy and immunodiagnostics. One of the obstacles in IgY purification from egg yolk is separating Ig from fat, so that IgY purification techniques are always developing. This study aimed to purify IgY from egg yolk using sodium chloride (NaCl) precipitation method and to characterize influenza-specific IgY. Sodium chloride was chosen because this chemical is relatively unexpensive, environmentally friendly, and does not impair IgY immunoactivity. The egg yolks used in this study were collected from layer eggs vaccinated with the Flubio® influenza vaccine, which contains the Influenza A/H3N2, A/H1N1 and B/Washington viruses. IgY purification was only carried out on egg yolks containing influenza specific antibodies. The presence of influenza-specific antibodies was determined by the agar gel precipitation (AGP) test and the enzyme linked immunosorbent assay (ELISA) method. The purified IgY concentration was determined using spectrophotometer, and protein characterization was performed using the Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) method. Protein concentration from purification has a mean value of 50,403 mg/mL . SDS-PAGE result showed six protein bands, namely intact IgY structure (174,63 kDa), Apoprotein-LDL (129,77 kDa), IgY heavy chain (66,54 kDa), Fab (47,65 kDa), IgY light chain (21,85 kDa), and β-livetin (36,74 kDa). The purified IgY still able to bind with influenza antigen based on the ELISA test. The results of this study indicate that purification of IgY using the NaCl precipitation method can purify IgY with intact structure, although there are still two unspecific proteins in the purification results. The resulting IgY can bind to influenza antigens indicating the
Keyword: Immunoglobulin Y, influenza, egg yolk, purification, sodium chloride