Judul: Kerusakan dan Pemulihan Pohon Pinus Akibat Penyadan pada Berbagai Ketinggian Tempat di KPH Kediri
Abstrak: Tingkat kerusakan pohon pinus akibat penyadapan didasarkan pada parameter jumlah sadapan, lebar sadapan, tinggi sadapan dan kedalaman sadapan. Ketinggian tempat tumbuh pohon pinus dapat mempengaruhi pemulihan pada bidang sadapan pinus karena kondisi cuaca, suhu udara dan intensitas sinar matahari di setiap ketinggian berbeda. Penelitian ini bertujuan mengetahui kondisi pohon pinus akibat penyadapan, mengukur persentase pemulihan bidang sadapan pohon pinus dan menganalisis pengaruh ketinggian tempat terhadap pemulihan bidang sadapan. Hasil penelitian menunjukkan rata-rata kerusakan sadapan di setiap ketinggian tidak memenuhi prosedur penyadapan getah pinus yang sudah diterapkan oleh Perhutani kecuali rata-rata ketinggian sadapan. Ketinggian tempat berpengaruh terhadap pemulihan bidang sadapan. Rata-rata persentase pemulihan bidang sadapan yang paling tertinggi terdapat di ketinggian <400 m di atas permukaan laut (mdpl) dengan nilai sebesar 50.40%/sadapan dan rata-rata persentase pemulihan bidang sadapan yang paling terendah terdapat di ketinggian >1.000 mdpl dengan nilai sebesar 36.05%/sadapan., The level of damage to pine trees due to tapping is based on parameters such as the number of taps, the width of the taps, the height of the taps, and the depth of the taps. The altitude at which pine trees grow can affect the recovery of the tapped areas because weather conditions, air temperature, and sunlight intensity vary at different altitudes. This study aims to determine the condition of pine trees due to tapping, measure the percentage of recovery of tapped areas on pine trees, and analyze the influence of altitude on the recovery of tapped areas. The results showed that the average damage from tapping at each altitude did not meet the tapping procedures established by Perhutani, except for the average height of the taps. Altitude affects the recovery of tapped areas. The highest average recovery percentage of tapped areas was found at an altitude of <400 meters above sea level (masl) with a value of 50.40% per tap, while the lowest average recovery percentage of tapped areas was found at an altitude of >1,000 masl with a value of 36.05% per tap.
Keyword: Kerusakan sadapan, Ketinggian tempat, Pemulihan bidang sadapan, Penyadapan, Altitude, Recovery of tapped areas, Tap damage, Tapping

Judul: Pengaruh Tingkat Kerusakan Pohon Akibat Penyadapan terhadap Produktivitas Getah Pinus di KPH Cianjur Jawa Barat
Abstrak: Profitability targets of Perum Perhutani for pine resin production tend to increase every year, resulting in overtapping and have a bad impact on the tree stands, lowering the productivity of pine resin. Therefore, the use of drilling method was chosen for tapping. The tapping areas are smaller and the recovery of tapping is relatively short so that tree damage can be minimized. The objective of this study was to get a description of various levels of tree damage and resin productivity, to learn about the effect of tree damage on productivity levels of pine resin and to obtain a model to estimate the relationship between the level damage of pine tree and pine resin productivity. Of the 400 overtapped pine trees, the level of tree damage ranged from 4.11-85.54%, the average was 44.58%, the median was 46.16% and the standard deviation was 17.26%. Resin productivity ranged between 0-4.58 g/tree/day, the average was 0.77 g/ tree/day, the median was 0.54 g/tree/day, the mode was 0.13 g/tree/day and the standard deviation was 0.71 g/tree/day. The higher the damage level caused by resin tapping, the lower the pine resin productivity. Pine resin productivity can be predicted by the tree damage level with the best regression model in this study, that is, using a model of: Y=(1.63697+(-0.10739)X)/(1+(-0.04606)X+(-0.00145)X²)
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Judul: Mathematical model of Hematopoietic Stem Cell in Chronic Myelogenous Leukemia with and without Therapy
Abstrak: Leukemia or blood cancer is a diverse group of neoplastic disease, characterized by the multiplication of abnormal leukocytes or malignant transformation of blood-forming cells in bone marrow and lymphoid tissues. One of the most common types of leukemia is Chronic Myelogenous Leukemia (CML), which is usually diagnosed by the presence of certain chromosomal abnormalities, the so-called Philadelphia chromosome (Ph). One of the treatments of CML is Granulocyte Colony-Stimulating Factor (G-CSF). In this paper, we discuss two Hematopoietic Stem Cell (HSC) models, i.e. HSC without treatment and HSC with G-CSF treatment. The model of HSC without treatment included three equations representing the dynamics of HSC, leukocyte and platelet. Whereas, the model of HSC with G-CSF treatment includes the previous three equations and adds two more equations representing G-CSF injection and G-CSF circulation. The stability behavior of the system approaching the equilibrium points in the simulation study is carried out using Mathematica 7.0. The simulation results show that the G-CSF treatment can successfully decrease the number of HSC, which means reducing the CML.
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