РефератыИностранный языкScScience Essay Research Paper Materials and MethodsThe

Science Essay Research Paper Materials and MethodsThe

Science Essay, Research Paper


Materials and Methods


The first experiment involved examining the effect of temperature on aerobic


respiration of germinated pea seeds. The students testing the effect of temperature, will


be divided into two groups. The first group is Student Pair A. They will test the effect of


10C, 20C and 30C temperatures on pea respiration rate. The second group is Student Pair


B. They will test the effect of 40C and 70C temperatures on pea respiration rate. For both


groups, the first procedure calls for writing down a hypothesis to the effects of


temperature on the respiration rate of germinated pea seeds. There are two parts to the


first experiment, the making of an experimental tube and the making of a control tube.


For the experimental tube, you must select 20 pea seeds and place them in a beaker filled


with cold tap water that you will get from the sink. The pea seeds will soak for 2 minutes.


After the 2 minutes are completed you will need to remove the seedcoat from the pea


seed. The seed coat is the thick light-green colored covering of the seed. You will be able


to remove the seedcoat easily if the pea seeds were soaked for the 2 minutes. After


removing the seedcoat, fill two plastic capsules with fresh lime soda. Take an


experimental test tube and place the 20 germinated pea seeds in it. The pea seeds should


almost fill the test tube. Place one of the lime soda capsules on top of the pea seeds in the


experimental test tube. Take a cork stopper and enclose the pea seeds and the lime soda


in the experimental tube. For the control tube, take 20 beads and place them in the test


tube. The beads should almost fill the test tube. Place the soda lime capsule in the test


tube. It should lay on top of the beads already in the test tube. The space taken up by the


beads in the control tube should be the same space taken up by the pea seeds in the


experimental tube. Remove the pea seeds and the soda lime capsule from the


experimental tube. Take all 20 of the pea seeds and weigh them together on the scale.


Weigh the pea seeds to the nearest 0.1g. Record their weight in Table 1. Set the pea seeds


that was weighed to the side , making sure that they are not agitated. These peas seeds are


the experimental peas and will be used for the remainder of the experiment. For the


control tube, remove the beads and the lime soda capsule. You will not need to weigh nor


record data as in the experimental tube.


Student Pair A procedure is to soak the 20 peas and the 20 beads for 10 minutes


in 10C tap water. The tap water will not be 10C, so you must add small amounts of ice to


the tap water. They must be soaked in water so that they can get gas. Measure the tap


water with a thermometer, making sure that it is 10C during the entire time the pea seeds


and the beads are soaking. After the water is prepared, fill the manometer water bath to


the top with 10C tap water. The manometer water bath is a round container with a


covering that has two small holes at the top. The covering allows test tubes to be placed


in it. Place the covering on top of the manometer bath water. Insert the experimental and


the control test tubes into the holes of the cover. Make sure that you hold the manometer


bath water with two hands on the base because if you hold it from the rim, it will break.


During the 10 minutes check the temperature of the water bath, making sure that it is


10C. If it warms up, add a few pieces of ice to get the temperature to 10C. When the ten


minutes are up, drain the peas and beads. Blot them dry very carefully with a towel. Take


the experimental and the control tubes out of the water bath. Quickly transfer the peas


into the experimental test tube and the beads into the control test tube, that are in the 10C


water bath. Place the soda lime capsules in each one of the test tubes. The soda lime


capsules remove carbon dioxide from the tube so that you can get an accurate response of


how much oxygen that the organisms are breathing Place the cork stopper tightly on the


experimental and the control tubes, using the rubber stopper and the t-rigs. Place the two


test tubes into the water bath and connect the plastic tubes of each of the t-rigs to the


metal connectors of the manometer block. Make sure that they are tightly secured but do


not force the plastic tubes all the way to the metal connectors. Allow the test tubes to set


for 5 minutes. Set the experimental syringe at 1.0cc and the control syringe at 1.0cc.


Close the experiment by close shut the rubber escape tubes of both t-rigs using metal


clamps. The metal clamps should be placed at the middle of the escape tubes so that


there is a less possibility that air will escape. They should be closed at the same time.


Adjust the manometer fluid with the syringe attached to the t-rig. The height should be


equal on both sides of the U-tube. Take a wax pencil and mark the level of the


manometer fluid. In table 1 record the setting of the experimental syringe and the time.


After every two minutes re-level the manometer fluid back to the starting level, that you


marked off with the wax pencil. You can do this by depressing the syringe plunger on the


experimental t-rig. Record the results on table 1. This should be done for 12 minutes. The


difference of the experimental syringe reading after leveling the manometer fluid and


that after 2 minutes is the amount of oxygen that was consumed by the peas. After the 12


minutes are completed and the 2 minute results are recorded, open the experiment by


removing the metal clamps from the escape tubes. Make sure that manometer fluid does


not move into the brass connectors are the t-rigs, when removing the metal clamps. If this


should happen. clean it out using pipe cleaners before proceeding with the next


experiments. For the 20C and the30C experiment you will repeat all the steps. This time,


you will need to fill the manometer bath with 20c and 30C water. Always check the


temperature with a thermometer, so that it will remain constant.


The procedure for Student Pair B begins by soaking the 20 peas and the 20 beads in


40C tap water for 10 minutes. Make sure that the water stays at the 40C temperature by


periodically checking it with a thermometer. While the peas are soaking, fill the


manometer water bath to the top with 40C tap water. Place the cover over the water bath


and then insert two test tubes through the holes of the cover and into the 40C tap water.


This will keep the test tubes warm. Check the temperature of the water bath before the 10


minutes are complete. After soaking for 10 minutes, drain the 20 pea seeds and the 20


beads. Take the experimental and the control test tubes out of the 40C after bath and


quickly transfer the pea seeds in the experimental test-tube and the beads in the control


test tube. Place the soda lime capsule in each of the experimental and control test tubes.


Tightly place the rubber stopper with attached T-rigs on each on the test tubes. Place the


test tubes into the 40C manometer water bath and connect the plastic tubing of each T-rig


to the metal connectors of the manometer block. Make sure that you do not force the


plastic tubes all the way to the metal connectors. Allow the test tubes to stay in the 40C


bath water for 5 minutes. Set the experimental syringe at 1.0cc and the control syringe at


0.5cc. Place the metal clamps in the middle of the robber escape tubes, so that air will


not be able to escape. Using the syringe attached to the control T-rig, adjust the


manometer fluid so that it is equal height on both sides of the U-tube. Mark the level with


a wax pencil. In table 1, record the setting of the experimental syringe and the time. After


2 minutes, re-level the manometer fluid to its starting level by depressing the syringe


plunger on the experimental T-rig. In table 1 record the new reading on the experimental


syringe. Start timing the reaction for another 2 minutes. This should be done for a total of


12 minutes. You should have a total of 6 results. In the procedure for 70C temperature,


take a metal pan and place a dry paper towel in it. Write your initials on the paper towel


so that you will be able to identify your pan. Take the experimental tube and the control


tube and empty the contents into the metal pan. Dry the test tubes that was just emptied


and place them into the same metal pan. Place the pan into the 70C drying oven. Let it set


in the oven for 15 minutes. While the pan is setting in the oven, set up a 70C water bath.


Place hot water on to a hot plate to bring the temperature up to 70C. Fill the water bath


with hot tap water and the water that was on the hot plate. Check the temperature with a


thermometer to make sure that the water is 70 C. When the 15 minutes are completed


take the metal pan out of the oven using hot pads. If the tubes are not completely dry take


a small paper towel, roll it up, and clean out the test tubes. Place the 20 peas in the dry


experimental tube and the 20 beads in the dry control tube. Place a soda lime capsule in


each of the test tubes. Put the experimental and the control tubes into the water bath and


place the T-rig assembly without the metal clamps on each test tube. Let the test tubes set


in the 70C water bath for 10 minutes. After the 10 minutes are complete, close the system


with the metal clamps. Take 6, 2 minute readings of the respiration. Record them in table


1.


The second experiment involved examining the effects of temperature on


mealworm respiration rate. The students are divided into 2 groups: Student Pair A and


Student Pair B. The Student Pair A examined the effect of 10C, 20C, and 30C


temperatures on mealworm respiration. Student Pair B examined the effect of 40C and


55C temperatures on mealworm respiration. Both groups are to write down their


hypothesis as to the effects of temperature on the respiration rate of the mealworm


larvae, based on their knowledge of aerobic respiration. Select 20 mealworms from the


culture. Weigh the mealworms on a gram scale and measure them to the nearest 0.1g.


Record the weight of worms in Table 3 under the Student A or Student B, depending on


your classified group. Fill 2 plastic capsules with fresh lime soda. Gently place the worms


into the experimental test tube with twizzers. Place a small cotton plug 3/4 up the tubes


so the mealworms are not able to grab it. Place one of the lime soda capsules on top of


the cotton plug in the experimental test tube. Break toothpicks into small pieces and


place them into the bottom of the control test tube. Place a cotton plug on top of the


pieces of tooth picks and also place the other soda lime capsule on the test tube. It should


be lying on top of the cotton plug. The control tube and the experimental tube should


take up the same amount of space, so compare the two. Tightly stopper the experimental


and the control tubes using the rubber stoppers with attached T-rigs.


The procedure for Student Pair A starts by filling the manometer bath water to the


top with 10C tap water. Lower the experimental and control tubes into the 10C


manometer water bath and connect the plastic tubing of each T-rig to the metal


connectors of the manometer block. Let the tubes set for 15 minutes in the manometer


bath water. Set the experimental syringe at 1.0cc and the control syringe at 0.5cc. Close


the experiment by placing the metal clamps over the middle of the rubber escape tubes.


Use the syringe attached to the control T-rig and adjust the manometer fluid so that it is


equal height on both sides of the U-tube and mark the level with a wax pencil. Record the


setting on the experimental syringe and the time in Table 3. Read the changes in the


experimental syringe at 2 minute intervals for 12 minutes. You will have 6 readings. Rate


the activity of mealworms during the experiment. Rate them with 0= no movement,


+=slow movement, ++=moderate movement, or +++=rapid movement. Record the


observations in the last column of Table 3. After the measurements are completed at


10C, remove the metal clamps from the escape tubes. Repeat the steps for the


temperatures of 20C and 30C. Adjust the temperature of the bath water very carefully.


Allow the experiment to set for 15 minutes before closing the escape tubes and taking the


readings. Take 6 readings for each of the temperatures. Readings should be made every 2


minutes but at 30C it could be taken at every 1 minute.


The procedure for Student Pair B starts by filling the water bath to the top with


40C. Lower the experimental and control tubes into the 40C manometer water bath and


connect the plastic tubing of each t-rig to the metal connectors of the manometer blocks.


Allow the experiment to stay for 15 minutes. Set the experimental syringe at 1.0cc and


the control at 0.5cc. Close the experiment by placing the metal clamps on the rubber


escape tubes on both of the T-rigs. Adjust the manometer fluid so that it is equal height


on both sides of the U-tube and mark the level with a wax pencil. Record the setting on


the experimental syringe and the time in Table 3. After 1 minute re-level the manometer


fluid to its starting level, which should be marked by the wax pencil. In table 3 record the


new reading on experimental syringe and start timing the reaction for another minute.


The difference of the two readings on the experimental syringe represents the amount of


oxygen consumed by the meal worms. The recording should be in cc. Read the changes


every 1 minute for 6 minutes. Rate the activity of the meal worms and record in the last


column of table 3. For the procedure at 55C, line a metal pan with a damp towel. Place


the contents of the experimental and the control tube into the pan. Take a paper towel


and dry the inside and outside of the test tubes and place them in the metal pan. Place the


pan in the 55C drying oven and allow it to stay in there for 15 minutes. While the pan is


in the oven, prepare a water bath with 55C temperature. When the 15 minutes are


complete, remove the pan from the oven using hot pads. Place the mealworms, cotton,


and soda lime capsule into the experimental tube and place the toothpicks, cotton, and


soda lime into the control tube. Place the experimental and the control tube into the water


bath and put the t-rig assembly on each tube. Let the test tubes to set in the water for 10


minutes. Set the experimental syringe at 1.0cc and the control syringe at 0.5cc. Take the


metal clamps and close the rubber escape tubes of both t-rigs in the middle of the escape


tubes. Adjust the manometer fluid so that it is equal height on both sides of the U-tube


and mark the level with a wax pencil. Record the setting on the experimental syringe and


the time in Table 3. Record it in cc. After 1 minute, re-level the manometer fluid to its


starting place by depressing the syringe plunger on the experimental t-rig. Record the


new reading on the experimental syringe and start timing the reaction for another 1


minute. This should be done every minute for 6 minutes. There should be

6 recordings.


Materials and Methods


The first experiment involved examining the effect of temperature on aerobic


respiration of germinated pea seeds. The students testing the effect of temperature, will


be divided into two groups. The first group is Student Pair A. They will test the effect of


10C, 20C and 30C temperatures on pea respiration rate. The second group is Student Pair


B. They will test the effect of 40C and 70C temperatures on pea respiration rate. For both


groups, the first procedure calls for writing down a hypothesis to the effects of


temperature on the respiration rate of germinated pea seeds. There are two parts to the


first experiment, the making of an experimental tube and the making of a control tube.


For the experimental tube, you must select 20 pea seeds and place them in a beaker filled


with cold tap water that you will get from the sink. The pea seeds will soak for 2 minutes.


After the 2 minutes are completed you will need to remove the seedcoat from the pea


seed. The seed coat is the thick light-green colored covering of the seed. You will be able


to remove the seedcoat easily if the pea seeds were soaked for the 2 minutes. After


removing the seedcoat, fill two plastic capsules with fresh lime soda. Take an


experimental test tube and place the 20 germinated pea seeds in it. The pea seeds should


almost fill the test tube. Place one of the lime soda capsules on top of the pea seeds in the


experimental test tube. Take a cork stopper and enclose the pea seeds and the lime soda


in the experimental tube. For the control tube, take 20 beads and place them in the test


tube. The beads should almost fill the test tube. Place the soda lime capsule in the test


tube. It should lay on top of the beads already in the test tube. The space taken up by the


beads in the control tube should be the same space taken up by the pea seeds in the


experimental tube. Remove the pea seeds and the soda lime capsule from the


experimental tube. Take all 20 of the pea seeds and weigh them together on the scale.


Weigh the pea seeds to the nearest 0.1g. Record their weight in Table 1. Set the pea seeds


that was weighed to the side , making sure that they are not agitated. These peas seeds are


the experimental peas and will be used for the remainder of the experiment. For the


control tube, remove the beads and the lime soda capsule. You will not need to weigh nor


record data as in the experimental tube.


Student Pair A procedure is to soak the 20 peas and the 20 beads for 10 minutes


in 10C tap water. The tap water will not be 10C, so you must add small amounts of ice to


the tap water. They must be soaked in water so that they can get gas. Measure the tap


water with a thermometer, making sure that it is 10C during the entire time the pea seeds


and the beads are soaking. After the water is prepared, fill the manometer water bath to


the top with 10C tap water. The manometer water bath is a round container with a


covering that has two small holes at the top. The covering allows test tubes to be placed


in it. Place the covering on top of the manometer bath water. Insert the experimental and


the control test tubes into the holes of the cover. Make sure that you hold the manometer


bath water with two hands on the base because if you hold it from the rim, it will break.


During the 10 minutes check the temperature of the water bath, making sure that it is


10C. If it warms up, add a few pieces of ice to get the temperature to 10C. When the ten


minutes are up, drain the peas and beads. Blot them dry very carefully with a towel. Take


the experimental and the control tubes out of the water bath. Quickly transfer the peas


into the experimental test tube and the beads into the control test tube, that are in the 10C


water bath. Place the soda lime capsules in each one of the test tubes. The soda lime


capsules remove carbon dioxide from the tube so that you can get an accurate response of


how much oxygen that the organisms are breathing Place the cork stopper tightly on the


experimental and the control tubes, using the rubber stopper and the t-rigs. Place the two


test tubes into the water bath and connect the plastic tubes of each of the t-rigs to the


metal connectors of the manometer block. Make sure that they are tightly secured but do


not force the plastic tubes all the way to the metal connectors. Allow the test tubes to set


for 5 minutes. Set the experimental syringe at 1.0cc and the control syringe at 1.0cc.


Close the experiment by close shut the rubber escape tubes of both t-rigs using metal


clamps. The metal clamps should be placed at the middle of the escape tubes so that


there is a less possibility that air will escape. They should be closed at the same time.


Adjust the manometer fluid with the syringe attached to the t-rig. The height should be


equal on both sides of the U-tube. Take a wax pencil and mark the level of the


manometer fluid. In table 1 record the setting of the experimental syringe and the time.


After every two minutes re-level the manometer fluid back to the starting level, that you


marked off with the wax pencil. You can do this by depressing the syringe plunger on the


experimental t-rig. Record the results on table 1. This should be done for 12 minutes. The


difference of the experimental syringe reading after leveling the manometer fluid and


that after 2 minutes is the amount of oxygen that was consumed by the peas. After the 12


minutes are completed and the 2 minute results are recorded, open the experiment by


removing the metal clamps from the escape tubes. Make sure that manometer fluid does


not move into the brass connectors are the t-rigs, when removing the metal clamps. If this


should happen. clean it out using pipe cleaners before proceeding with the next


experiments. For the 20C and the30C experiment you will repeat all the steps. This time,


you will need to fill the manometer bath with 20c and 30C water. Always check the


temperature with a thermometer, so that it will remain constant.


The procedure for Student Pair B begins by soaking the 20 peas and the 20 beads in


40C tap water for 10 minutes. Make sure that the water stays at the 40C temperature by


periodically checking it with a thermometer. While the peas are soaking, fill the


manometer water bath to the top with 40C tap water. Place the cover over the water bath


and then insert two test tubes through the holes of the cover and into the 40C tap water.


This will keep the test tubes warm. Check the temperature of the water bath before the 10


minutes are complete. After soaking for 10 minutes, drain the 20 pea seeds and the 20


beads. Take the experimental and the control test tubes out of the 40C after bath and


quickly transfer the pea seeds in the experimental test-tube and the beads in the control


test tube. Place the soda lime capsule in each of the experimental and control test tubes.


Tightly place the rubber stopper with attached T-rigs on each on the test tubes. Place the


test tubes into the 40C manometer water bath and connect the plastic tubing of each T-rig


to the metal connectors of the manometer block. Make sure that you do not force the


plastic tubes all the way to the metal connectors. Allow the test tubes to stay in the 40C


bath water for 5 minutes. Set the experimental syringe at 1.0cc and the control syringe at


0.5cc. Place the metal clamps in the middle of the robber escape tubes, so that air will


not be able to escape. Using the syringe attached to the control T-rig, adjust the


manometer fluid so that it is equal height on both sides of the U-tube. Mark the level with


a wax pencil. In table 1, record the setting of the experimental syringe and the time. After


2 minutes, re-level the manometer fluid to its starting level by depressing the syringe


plunger on the experimental T-rig. In table 1 record the new reading on the experimental


syringe. Start timing the reaction for another 2 minutes. This should be done for a total of


12 minutes. You should have a total of 6 results. In the procedure for 70C temperature,


take a metal pan and place a dry paper towel in it. Write your initials on the paper towel


so that you will be able to identify your pan. Take the experimental tube and the control


tube and empty the contents into the metal pan. Dry the test tubes that was just emptied


and place them into the same metal pan. Place the pan into the 70C drying oven. Let it set


in the oven for 15 minutes. While the pan is setting in the oven, set up a 70C water bath.


Place hot water on to a hot plate to bring the temperature up to 70C. Fill the water bath


with hot tap water and the water that was on the hot plate. Check the temperature with a


thermometer to make sure that the water is 70 C. When the 15 minutes are completed


take the metal pan out of the oven using hot pads. If the tubes are not completely dry take


a small paper towel, roll it up, and clean out the test tubes. Place the 20 peas in the dry


experimental tube and the 20 beads in the dry control tube. Place a soda lime capsule in


each of the test tubes. Put the experimental and the control tubes into the water bath and


place the T-rig assembly without the metal clamps on each test tube. Let the test tubes set


in the 70C water bath for 10 minutes. After the 10 minutes are complete, close the system


with the metal clamps. Take 6, 2 minute readings of the respiration. Record them in table


1.


The second experiment involved examining the effects of temperature on


mealworm respiration rate. The students are divided into 2 groups: Student Pair A and


Student Pair B. The Student Pair A examined the effect of 10C, 20C, and 30C


temperatures on mealworm respiration. Student Pair B examined the effect of 40C and


55C temperatures on mealworm respiration. Both groups are to write down their


hypothesis as to the effects of temperature on the respiration rate of the mealworm


larvae, based on their knowledge of aerobic respiration. Select 20 mealworms from the


culture. Weigh the mealworms on a gram scale and measure them to the nearest 0.1g.


Record the weight of worms in Table 3 under the Student A or Student B, depending on


your classified group. Fill 2 plastic capsules with fresh lime soda. Gently place the worms


into the experimental test tube with twizzers. Place a small cotton plug 3/4 up the tubes


so the mealworms are not able to grab it. Place one of the lime soda capsules on top of


the cotton plug in the experimental test tube. Break toothpicks into small pieces and


place them into the bottom of the control test tube. Place a cotton plug on top of the


pieces of tooth picks and also place the other soda lime capsule on the test tube. It should


be lying on top of the cotton plug. The control tube and the experimental tube should


take up the same amount of space, so compare the two. Tightly stopper the experimental


and the control tubes using the rubber stoppers with attached T-rigs.


The procedure for Student Pair A starts by filling the manometer bath water to the


top with 10C tap water. Lower the experimental and control tubes into the 10C


manometer water bath and connect the plastic tubing of each T-rig to the metal


connectors of the manometer block. Let the tubes set for 15 minutes in the manometer


bath water. Set the experimental syringe at 1.0cc and the control syringe at 0.5cc. Close


the experiment by placing the metal clamps over the middle of the rubber escape tubes.


Use the syringe attached to the control T-rig and adjust the manometer fluid so that it is


equal height on both sides of the U-tube and mark the level with a wax pencil. Record the


setting on the experimental syringe and the time in Table 3. Read the changes in the


experimental syringe at 2 minute intervals for 12 minutes. You will have 6 readings. Rate


the activity of mealworms during the experiment. Rate them with 0= no movement,


+=slow movement, ++=moderate movement, or +++=rapid movement. Record the


observations in the last column of Table 3. After the measurements are completed at


10C, remove the metal clamps from the escape tubes. Repeat the steps for the


temperatures of 20C and 30C. Adjust the temperature of the bath water very carefully.


Allow the experiment to set for 15 minutes before closing the escape tubes and taking the


readings. Take 6 readings for each of the temperatures. Readings should be made every 2


minutes but at 30C it could be taken at every 1 minute.


The procedure for Student Pair B starts by filling the water bath to the top with


40C. Lower the experimental and control tubes into the 40C manometer water bath and


connect the plastic tubing of each t-rig to the metal connectors of the manometer blocks.


Allow the experiment to stay for 15 minutes. Set the experimental syringe at 1.0cc and


the control at 0.5cc. Close the experiment by placing the metal clamps on the rubber


escape tubes on both of the T-rigs. Adjust the manometer fluid so that it is equal height


on both sides of the U-tube and mark the level with a wax pencil. Record the setting on


the experimental syringe and the time in Table 3. After 1 minute re-level the manometer


fluid to its starting level, which should be marked by the wax pencil. In table 3 record the


new reading on experimental syringe and start timing the reaction for another minute.


The difference of the two readings on the experimental syringe represents the amount of


oxygen consumed by the meal worms. The recording should be in cc. Read the changes


every 1 minute for 6 minutes. Rate the activity of the meal worms and record in the last


column of table 3. For the procedure at 55C, line a metal pan with a damp towel. Place


the contents of the experimental and the control tube into the pan. Take a paper towel


and dry the inside and outside of the test tubes and place them in the metal pan. Place the


pan in the 55C drying oven and allow it to stay in there for 15 minutes. While the pan is


in the oven, prepare a water bath with 55C temperature. When the 15 minutes are


complete, remove the pan from the oven using hot pads. Place the mealworms, cotton,


and soda lime capsule into the experimental tube and place the toothpicks, cotton, and


soda lime into the control tube. Place the experimental and the control tube into the water


bath and put the t-rig assembly on each tube. Let the test tubes to set in the water for 10


minutes. Set the experimental syringe at 1.0cc and the control syringe at 0.5cc. Take the


metal clamps and close the rubber escape tubes of both t-rigs in the middle of the escape


tubes. Adjust the manometer fluid so that it is equal height on both sides of the U-tube


and mark the level with a wax pencil. Record the setting on the experimental syringe and


the time in Table 3. Record it in cc. After 1 minute, re-level the manometer fluid to its


starting place by depressing the syringe plunger on the experimental t-rig. Record the


new reading on the experimental syringe and start timing the reaction for another 1


minute. This should be done every minute for 6 minutes. There should be 6 recordings.

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