Didik Rahadi Santoso

Implementation of Town Watching and Development of Observatory for Community Education in Volcano Hazard Mitigation: study case at Kelud and Arjuno-Welirang volcanoes, East Java, Indonesia

A Town Watching has been implemented at Kelud volcano region and an Observatory is being developed at Arjuno-Welirang Volcano Hosted Geothermal area in order to improve community education for volcano hazard mitigation in East Java, Indonesia. From the results shown that the level of participants interest was good because more than 75% expressed interest in the Town Watching implementation and 70% participants stated that they understand about the material presented at the event. All of the participants stated that the Town Watching was necessary and they hope that it could be done periodically. Almost 95% participants satisfied and 90% participants expected that similar town watching should be done in the future. In addition, an observatory of volcano was being developed at Arjuno-Welirang volcano complex in strengthening education in the field of volcano hosted geothermal. The observatory can be developed as part of pilot project in community education in that field. In the future, it can be integrated with town watching as a unity in education and research in the field of volcano hazard mitigation.

Analysis of Voltage Difference Characteristics of Albumin Membranes and Vitelin Membranes of Chicken Eggs through Diazinon Effects

Cells are the most important structural and functional part of any organism. Cells are protected by cell membranes that envelop cells, and separate cells with their environment. The effectiveness of the work of a cell membrane can be disrupted for various reasons, one of which is pesticide contamination. Pesticides in cells can damage cell metabolism or cell membrane permeability. Therefore, this study aims to determine how big the effect of diazinon insecticides on the characteristics of different potential membrane vitelin and membrane albumin chicken egg cells. Measurements were made using the microelectrode connected with the picoscope 5000 series, then the data appears displayed through the PC. The results of membrane potential measurements showed that the greater the concentration of insecticide given, the potential value of chicken egg membrane increased. Potential Differential Values Membrane of eggs with different concentrations ranged in -145 mV - 249 mV on vitelin membrane, and -142,5 mV - 242,5 mV on albumin membrane

Electrical Impedance Value Analysis on Formalinized Tilapia Fish Meat

Electrical impedance can be used as a non-destructive method to determine the bio-electrical characteristics on biological materials. Analysis of the electrical impedance value by using an electrode needle method has been applied to the tilapia flesh which aims to determine the bio-electrical characteristics on tilapia flesh, and determine the effect of formalin on it. The measurements were carried out to compare the characteristics of bio-electrical characteristics of the fresh tilapia flesh, the tilapia flesh soaked in formalin, and the one that was lay without any preservation treatment at a 10 Hz - 200 kHz frequency. The result shows that the impedance value characteristics of the fresh tilapia flesh decreased as long as the increase of frequency. Both the preserved and the rotten tilapia flesh have the decreased impedance value. The concentration of formalin immersion is directly proportional with the value of electrical impedance.