Yogya Day 6

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Day 6 (06 Sept 2015)


Today our breakfast was bihun (like noodles), nasi and sambal. Sambal was very spicy.


Morning check in meeting

In the morning discussion session we went back to hypothesis session which is "meat market is more dirty then other market" the idea is we going to take the sample form the meat market like the left over form the sample from meat shop. We will take from trash, floor and we also want to test humanity, temp. We also ask question in the group was what kind of data do we need? What kind of tool we need.We discuss we will need PCR, microscope, thermometer, humanity meter, centrifuge. Marc show up and advise us growth bacteria and we start listing for the shopping. Shopping list are chemical things such as alcohol, gloves, petri dishes, agar-agar etc… but we couldn’t shopping because today is Sunday and most shop are closed. Cianan showed me the science lab book which is about many things of science. (TZ)

Morning development session

We went back to respective groups to start working on potential instruments to test our hypothesis. In my group, our hypothesis was, “If the meat market is cleaned up, the overall hygiene of the market will increase as well.” In order to test the hypothesis, we decide to define hygiene in terms of the bad microorganisms that exist in the market due to unhygienic standards of handling meat. Some of the ideas on the types of lab equipment to identify and measure the types of microorganisms are PCR, centrifuge, and microscope. However, our advisor, Marc, suggested that we start with something more basic as the equipments that we want to make are more geared towards microbiology. We then shifted gears to grow bacterias in a sterile environment to learn about the different types of bacterias and their behavior. In order to run this experiment, we brainstormed a list of accessible and affordable materials needed. -KW


Afternoon development session

Day 6 for development our project. To day Lilly had a great idea to experimental about the relationship between bacteria, chemical, and electricity. She told me about the idea to put some metal in the water glass and connect to the electricity. The first problem was we don’t know how to connected electricity to metal and what type of electricity can used in this situation. we get some situation and used the power supply to changed the home electricity to direct electricity. Next we test with Zinc and tap water. We found some reaction and some grass from one side of reaction. Next we change to test with copper and tap water. we found the reaction. but different from past situation was the dust from reaction were blue color. Finally Lilly went to the river and got some sample water came back. When we test we found the result same the water from house or drinking water.

""In my opinion we cannot used this experimental to measure the bacteria in water. And cannot used to measure the water quality. Because this experimental can show It had some chemical in water. We were not knew the type of this element. Every water have some chemical or drinking just had some mineral. Only water not have chemical. It was “Distillate water” and It can not drink and find in nature. It’s not make sense if we used this system to measure the information. That was we want to knew. If we came back to the hypothesis. We want to know the quality of water from different place (filter or no filter) we should find the factor to drive this situation.""

Today I have some idea about we should focused to only type of data. For example we want to knew different side of water were Biological, Chemical, Physical. That was a lot of work if we want to knew every thing. So if we were focussing to on type of bacteria, one element or one side of physical. And create some solution by this concept. The result of this activity we can think by thinking process and used to correct every problem.

I have some idea about the way to identification bacteria. By I found some information about the behavior of bacteria such as food or product. This specific to the type of bacteria. If we can measure the volume of acid (bacteria production) by pH process we can knew the type of bacteria. I focused to E.coli because it was specific to the human’s chit, If we found it was mean the low quality of water. And this water were not pass the treatment process (filter or something). Or I found it from water were pass the filter. It’s mean the government water cannot work. From this situation we can correct to the our hypothesis.

By we should create the grow media and mixed some glucose (food) and indicator (measure the pH). Next we get some water sample to this tube and wait 24 hr. Next bacteria eat glucose and make some acid to the environment. The indicator have to change the color by this color different specific to type of bacteria. Finally we read the color by spectrophotometer and generate the result by number of bacteria or type of bacteria.


There are many ways how to detect if there is bacteria or minerals in the water. One simple way is to make water electrolysis what basically "burns out" the bacteria. I have to note that there exists also good bacteria what we cant distinguish with this process. Electrolysis is a process of precipitating all drosses dissolved in the water. To build a electrolysis we need cables, aluminium or foil paper and high voltage transformer. One aluminium sticks needs to be connected with + and the other with - cable; place them into a glass; make sure that the sticks wont touch each other; now fill the glass with water.

We made 3 experiments together with Mas Yudi. We collected water samples from river, tap and from a drinking water gallon. After plugging in the transformer what uses ~84 V some Hydrogen and Oxygen was released. After some minutes the river water became foggy and some white foam started to float on the top of the water surface. Same thing happened with tap and drinking water but we detected less foam; it probably shows that there are bacteria and minerals also in filtered water. To make the same test with higher voltage then the bacteria in polluted water should make the bacteria burn black. For that we need safer equipment. The speculation is that if we use distilled water then no foam will appear.

Test 1.jpg


Since we didn’t have any materials yet to run the experiment, our time was spent on doing more research to understand the type of good and bad bacterias that are present in meat. Besides research, we also went to different groups to see what kind of equipments they were building. One of the groups build an electrolytic cell to test for the presence of microorganisms in river water while another group build a microscope from a webcam. It was interesting to see how the electrolytic cell group’s result was used as sample by the microscope group. I really like this synergy which encourages me to think about other potential lab equipments that can be used for various common tests to solve local problems. In order to come up with the types of common tests that could be run, I reflected on our field visits and revisited the problems that I saw in the local context. Here, I found how the visits to different parts of Yogyakarta gave me valuable nuggets of insight in the prototyping process and reinforced the philosophy of “turun padang” (the literal translation is “going down to the field”) to build something that matters. -KW

Alun Alun

Hermes took us to a place called Alun Alun, this is a very strange place, people ride in a circle on machines that are decorated with colorful, bright light ribbons. We went on a two-storey car in the form of chicken. And passes between two trees blindfolded. After we went to a cafe called Tempo gelato. I tried ice cream with spicy chocolate flavor and tasteful fruit called passion.

-Talgat 705-