Reblogging: GMOs vs. Artificial Selection

The Ricochet Science blog post below—written by a talented college senior—is an interesting introduction to the difference between GMOs and organisms that are the products of artificial selection. I want to share it with you because it’s informative and entertaining, but first I’ll clarify one point that isn’t completely clear from the original.

In genetic engineering, scientists use DNA technology to directly manipulate a genome. Genetic engineering produces genetically modified organisms (GMOs). A GMO may be a transgenic organism—one that has received DNA from another species—or may have had its own genes activated or deactivated to produce new phenotypes. For example, some cotton plants are GMOs that are transgenic because they have a gene encoding a bacterial toxin in their genome. The transgenic cotton plant is toxic to pests like moth caterpillars. If, instead, the cotton plant’s DNA were modified to boost the expression of an existing gene (perhaps one that promotes large cotton bolls), the cotton would still be a GMO, but it would not be transgenic.

With this clarification in mind, read on and enjoy the original blog post.

[Thank you to Matt Taylor for contributing to this introduction.]

——

Picture this, you’re making your lunch for class or work and you decide to pre-slice your apple because it’s easier to eat and heck, why not? Fast forward five hours, you’re already exhausted from the day and all you want to do is eat your apples with some peanut butter, but, SURPRISE! Your apple slices…

via Transgenic or GMO? What is the Difference? — Ricochet Science

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TED-Ed video: The Cancer Gene We All Have

My friend and colleague Michael Windelspecht recently produced a useful video about cancer. Complete with compelling animations, narration, and analogies, it’s a great launching point for in-class group work or for a homework assignment. The video’s explanations span from genetics and cell cycle control to cancer’s effects on the organism.

If you watch until the end at the link here (The Cancer Gene We All Have), you’ll see five multiple choice questions and three free-response questions to test your understanding. Below I’ve placed the video if you want to view it on YouTube, but you won’t get the see the assessment questions. Enjoy!

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Teaching cell chemistry with Legos

Behold, my trusty bag of Legos … well they’re not actually Legos because I couldn’t find a bag of plain old Legos. All of the Legos nowadays are sold in kits with wheels and roofs and other things I don’t want. So I bought a big bag of plastic bricks that LOOK like Legos. Here they are:bag-of-legos

I bought them because my students have such a hard time with the basics of cell chemistry for biology. The main idea I am trying to teach is that food consists of complex organic molecules (proteins, polysaccharides, nucleic acids, and fats) that are broken down into amino acids, monosaccharides, nucleotides, glycerol, and fatty acids via hydrolysis reactions in digestion. These small molecules enter the bloodstream and are distributed to cells, which use them to build their own large molecules or use them in respiration. It’s easy once you know how it works, but it’s pretty hard to learn it for the first time.

So I started using my Legos … err, plastic bricks … in Action Center, to help students use their hands to work with the ideas. Here is my strategy, in pictures.

1 — Food represents a mixture of organic molecules. Imagine that the assembly of blocks pictured below is a bite of a bacon, lettuce, and tomato sandwich. It contains proteins, polysaccharides, nucleic acids, and fats — the different shapes and colors of the bricks represent these different molecules.

food

2 — In the intestines, digestion (hydrolysis) breaks the food into smaller molecules.

digested-food

3 — These small molecules enter the bloodstream, and cells take them up. Here are a bunch of monosaccharides taken up by a cell.

glucose

4 — The cell uses the monosaccharides in respiration (you’d have to smash a brick into bits to illustrate this idea). Or the cell may use them to build polysaccharides, like glycogen, by dehydration synthesis. Below is a “glycogen molecule.”

starch

5 — Cells also absorb amino acids from the bloodstream. Here are a bunch of amino acids taken up by a cell. Notice that the monosaccharides in photo #4 all looked the same, because they were all glucose. The amino acids all look different, thanks to their different R groups.

amino-acids

6 — The cell assembles the amino acids into proteins, again by dehydration synthesis.

protein

7 — Now if another animal eats this organism, what will happen to the proteins, polysaccharides, and other large organic molecule the cell has produced? Why, they’ll be dismantled again, in hydrolysis.

In my experience, building and taking apart these molecules has been really helpful to students in learning the connections between digestion, hydrolysis, dehydration synthesis, and respiration.

Try it yourself! And if you have other ideas for teaching cell chemistry that have worked for you, please share them here.

 

 

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At the End, I’m Looking to the Start

I turned in my course grades yesterday and thought I’d spend some time looking back at something that my TAs asked our students in lab to write about during week 1. After the TAs introduced themselves and talked about their portion of the class, we asked the students to combine my own day 1 lecture with the TA presentations to answer this question:

What are some of the obstacles that you feel might keep you from being successful in BIOL 1005?

2016-12-19-09-59-16-am

Motivated students attend a study session outside of class.

Now that the final course grades are in, I thought it might be worth looking back at the answers to see if students correctly anticipated their own obstacles. Some students listed just one; others listed multiple obstacles. I have typed each one below, so some students are represented more than once in each list.

 


Students who earned an A initially perceived their obstacles as:

  • Not being able to comprehend the material because “science is not my strong suit.”
  • “I’ve never been good at science.”
  • “I do not particularly like science because I do not feel I’m good at it.”
  • “I am not the best test-taker even if I study really hard.”
  • Not understanding lab materials or information
  • Not being able to understand the material
  • Having limited time to study (from a first-year student enrolled in 18 hours)
  • Having limited background in biology
  • Not asking for help when needed
  • Course intensity
  • Feeling overwhelmed
  • Not studying enough
  • Finding the class uninteresting and not being motivated to work hard

Students who earned a B initially perceived their obstacles as:

  • “I’m not a lover of science.”
  • “I’m not a biology or science person.”
  • “I really don’t like biology so I can get easily bored.”
  • “I am not science brained.”
  • “Science has never been my best subject.”
  • “I have always struggled with science.”
  • “Science was never my best subject in high school. It was hard to stay interested in the material because it seemed pointless and I couldn’t connect it to things in my life at the time.”
  • “I’m awful at science. I’ve never been good at it. I’ve always struggled with it.”
  • Limited past experience with biology and science
  • Past experiences with science classes pose a mental obstacle
  • Language (this from an international student with limited English skills)
  • Not understanding how to do labs
  • Not understanding how the concepts fit together
  • Limited math skills
  • Not being comfortable with my lab group
  • Not having a diligent lab partner
  • Adjusting to college life
  • Nothing can keep me from being successful if I try as hard as I can
  • Not being very outgoing
  • Workload
  • Workload
  • Not being able to keep up with the pace
  • Lack of motivation to work on a class in which I am not interested in the topic
  • Not putting in the effort needed to succeed
  • Forgetting due dates
  • Not completing assignments on time
  • Remembering to check for course updates every day
  • Having commitments that force me to fall behind
  • Struggling to stay focused

Students who earned a C initially perceived their obstacles as:

  • “Me and biology do not really get along. I don’t get science.”
  • “I am not very good at biology.”
  • “Science and math skills and biology are not subjects that come easy to me.”
  • “I’m not great at science.”
  • “I have always had trouble understanding science.”
  • “I have never been passionate about biology.”
  • “Science is not my favorite subject, and it isn’t a subject I’m naturally good at.”
  • “I am not a science oriented person and understanding does not come easily to me.”
  • “I’m not very good with sciences.”
  • “Any science class is not my easiest course.”
  • Limited experience with biology
  • Difficulty of biology
  • Confusing terminology in biology
  • Discouragement and frustration
  • Time management
  • Keeping priorities straight
  • Lack of attendance
  • Lack of concentration
  • Forgetting to do assignments
  • Getting behind on homework
  • Keeping up with what is due and when
  • Finding the right time and place to study

Students who earned a D, W, or F initially perceived their obstacles as:

  • “I have to reread sentences with scientific terms several times before I can understand them.”
  • “I am terrible at science and have a hard time learning from a book.”
  • “I’ve never been great at math or science.”
  • “I have much more of an English/History interest than science and math so understanding certain concepts might be difficult.”
  • “I’m not the best science student.”
  • Lack of interest in the subject
  • I can’t usually connect with microscopic biology
  • I have forgotten most of the stuff I have learned about science and biology
  • Lack of prior knowledge about science
  • Language (from an international student)
  • I don’t like just studying definitions; I like hands-on activities
  • I may struggle with computational questions
  • I don’t have the best study habits
  • Keeping up with assignments
  • Not having time to complete lab activities
  • Study skills
  • Time management
  • Lack of focus, cellular devices, and difficult lab partners
  • Work and class load (this from a student who has two jobs, works 40 hours a week, and enrolled in 23 credit hours)

You may have noticed that I colored some of the statements red. Those all refer to a perceived, inherent inability to understand science. I found it interesting that this mindset accounted for 31% of the statements among students who eventually earned an A, 28% of statements from those who earned a B, 45% from those who earned a C, and 26% from those who earned a D, W, or F. You can probably see whatever message you want in those numbers, but what I choose to see reinforces the idea that success in science has nothing to do with whether a student is “a science person.” Heck, I remember myself asserting (as an undergraduate) that I couldn’t take science classes because “I am not a science person,” but I had never actually tried. Once I took chemistry and earned an A, my mindset about my own abilities flipped 180 degrees.

I have recently been thinking a lot about fixed vs. growth mindset, a concept popularized by psychologist Carol Dweck. If you have a fixed mindset about biology, you believe that you can’t do much to change your limited science talent — it is a “fixed trait.” In other words, if you believe you are simply not a science person, why would you invest your precious time trying to learn about biology? On the other hand, if you have a growth mindset you believe that you can develop your talents with hard work and by learning from your mistakes. On behalf of my own students, I am keen to learn more about how to shift a fixed mindset into a growth mindset.

I also colored a few of the perceived obstacles green; these are not specific to science but rather seem to be rooted in student anxiety about keeping up with a challenging class in general. Finally, blue statements represent students’ self-perceived limitations in study skills or time management.

I found it interesting that students who eventually received an A or a B seemed more likely to express anxiety about how difficult the course would be than those who earned lower grades. Students who ended up with a C or below were honest that a major obstacle could be their general abilities as students. In essence, students who ultimately did better were more likely to blame “a course that’s just too hard” for poor performance, whereas students who ultimately did worse were more likely to blame themselves. That’s the opposite of what I would have expected.

This represents a small snapshot of just one semester, but it may provide a little insight into the student mind. How can we use this information to improve the odds of student success? That’s a good thought question for the upcoming break.

Thank you to Matt Taylor for help with this blog post.

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On Obstacles, part 2

My last blog post described three questions we asked students in my nonmajors biology class a few weeks ago. That post described some of the responses to question 1 (“What do you feel is your greatest obstacle in achieving the grade you want in this class?”). Today’s post examines answers to questions 2 and 3. Question 2 was this:

“What is one thing that is being done regularly in lab or lecture that helps you?”

Clicker questions: Two responses tied for the top, with 11 students apiece. One of these responses was “Clicker questions.” It is possible that students perceive clicker questions as a way to pad a sagging grade, but I don’t interpret the response in that way. One reason is that students do not earn “participation points” for clicker questions – they get 1 point for a correct response, and 0 points for an incorrect one. If they miss all three questions one day, they earn 0 points for the day. Although they may discuss the answers with their peers, students are ultimately responsible for paying attention and clicking the right answer. Another reason I think they are not simply “easy points” is that most of the clicker questions require understanding or application; they do not typically reward factual recall.

iclicker2 on notebook

Students benefit from clicker questions. (Photo by M. Hoefnagels)

Lecture: The other response tied for the top spot had to do with lecture. Eleven students mentioned lecture in general or specific lecture features such as analogies, examples, explanations, or images. In addition, four students mentioned some “non-content” aspects of lecture, like study tips and announcements about upcoming assignments. The mention of study tips in particular surprised me, mostly because students look so utterly disinterested when I present them! I guess my sage advice must be sinking in for a few of the students, so I’ll keep presenting my best ideas for student success.

Hands-on activities: Five students mentioned that they liked it when lab offered hands-on activities that reinforce content from lecture. Another handful mentioned outside help, like Action Center and tutoring with Allyson, our wonderful Peer Learning Assistant for BIOL 1005.

cropped-biol1005ac_100812-034.jpg

Mariëlle explains a concept during Action Center. (Photo by Mark Walvoord)

 


While it’s always gratifying to know what’s working, it’s hard to use that information to make improvements. That brings us to question 3:

“Is there something that is not being done that you could see helping you before your next test?”

Review sessions and resources: This question had a clear winner, with 16 students wanting an in-class review session (which was already on the schedule for exam 2). In addition, one student wanted me to tell the class (perhaps unrealistically) “exactly what to know for the test.” Another wanted “a list of possible types of test questions,” and another wanted practice tests. The latter two reflect some ignorance of available resources, because two semesters’ worth of old exams are already posted on my website.

Connecting labs to lectures: Interestingly, nine students mentioned wanting to know more about how labs are connected to the lectures (or simply wanted more help in lab). Last fall, we implemented our semester-long concept mapping project specifically to solve this problem. The basic idea is to build a small concept map near the start of the semester and add to it periodically as new concepts are covered in the class, incorporating terms from both lecture and lab. (You can read about it at the 2016 ABLE conference website; scroll about ¾ of the way down the page to the abstract by Krystal Gayler and Mariëlle Hoefnagels). Perhaps this semester’s TA’s are not emphasizing the purpose of these concept maps like the TA’s did last fall.

Online lecture slides: Incidentally, only one student wanted me to post lecture slides online. As someone who automatically stops paying attention at talks for which I already have the slides, I have resisted this request for the past 19 years. The fact that students are not clamoring for the slides suggests that I am not going too fast in lecture, which is good news for me.

Concept mapping: I want to wrap up this two-post series with a comment from one student, who wrote “Build a concept map WITH us.” In the first post, I ended by speculating on ways to help students build connections. I have so far avoided being too hands-on with concept maps in class, because I want to avoid the implication that the only correct concept map is the one that the instructor builds. I also want students to think for themselves and to perceive that learning is a struggle; I don’t want them to just mimic what I put on the screen. But I wonder if a little coaching would be beneficial. For example, students can come up to the board individually or in pairs to add new terms to the map or to revise existing connections. I can stand to the side, pointing out where language needs to be more specific or where additional connections might work.

ActionCenter

A student adds to a concept map. (Photo by M. Hoefnagels)

 


Conclusions from the survey

Overall, this three-question exercise revealed that some students are afraid of not being able to make the connections they need to be successful, yet they aren’t using the resources that could help. One explanation is that they don’t have time or that they’re lazy. Another is that they don’t feel confident that they know how to use the resources, so using them together in class could make a big difference.

Please share your observations and suggestions by leaving a comment.

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On Obstacles, part 1

A couple of weeks ago, I asked my lab TA’s to have our students write their answers to these questions:

What do you feel is your greatest obstacle in achieving the grade you want in this class? What is one thing that is being done regularly in lab or lecture that helps you? Or is there something that is not being done that you could see helping you before your next test?

hurdle_28psf29

What hurdles do your students have to clear on their paths to success? Image cred: Wikimedia Commons

We got 60 responses across two sections.

I’d like to share some of their answers with you. The first question, and the subject of today’s post, is “What do you feel is your greatest obstacle in achieving the grade you want in this class?” I’ll tackle the other two questions in a future blog post.

Seventeen students (more than 25% of students who responded) alluded to their difficulty in understanding how the material fits together. In a way, I am not surprised that this response led the pack, because I frequently emphasize to my students that memorizing vocabulary words will not be enough to do well in the course. On the other hand, it is puzzling because I provide so many resources that should help students focus on connections. Or at least I think I do … hmm. I will return to this point at the end of this post.

About 10 students alluded to time in some form or another – some have trouble staying on top of all of their classes, some can’t come to office hours or Action Center (supplemental learning session) because of other commitments, some admitted to not devoting enough time to studying, some mentioned “time management” in general, and a couple admitted to procrastinating. Other than reminding students to keep up with the material and not limit their studying to the time immediately preceding an exam, I am not sure what I can do as an instructor to help.

Speaking of time, I won’t waste yours by listing all of the responses that only a handful of students made, but a couple of them are noteworthy. Five students mentioned “information overload.” That one makes a lot of sense to me, partly because this is a 5-hour course and partly because of the two responses I mentioned already. If you have difficulty making connections and don’t study as you go along, I can see how it would be easy to perceive biology as a meaningless series of difficult vocabulary words. If you can instead picture how everything works together, it becomes much easier to incorporate new information without feeling overwhelmed by it all.

Six students mentioned a lack of focus/motivation (this is a nonmajors class, after all). Of these, one wrote, “Biology doesn’t click and it’s not interesting” and another wrote, “I don’t enjoy biology, so it’s not interesting, so it’s hard to learn.” As an instructor who works really hard to help students see why biology is interesting and relevant, these comments are painful to read. If I take the “glass half full” attitude, I could remind myself that only a few students feel that way and that I can’t please everyone. On the “glass half empty” side, I could ask myself what I could do differently to open students’ eyes to biology.

Since students can quickly get bored with subjects they perceive to be incomprehensible, maybe the best thing I can do is to shift my gaze back to the “difficulty in understanding” response that led off this blog post. I already use clicker questions in nearly every class, and the questions focus on understanding (not factual recall). However, perhaps more of them should focus on the big picture instead of on specific processes. We also draw concept maps frequently in Action Center, every few weeks in lab, and occasionally in lecture; perhaps I should work more of them into lecture.

I also provide many resources on my website, but maybe too many students focus on the old exams and not enough of them dig into the Guided Reading Questions. These resources, which you can see on my teaching website, direct students to the most relevant Mastering Concepts, multiple choice, and Write it Out questions from the textbook; I also sprinkle in occasional lists of words they can assemble into concept maps. (Do my “Guided Reading Questions” need a snappier name? Maybe so…I am open to suggestions!) One good way to show them off might be to develop a team exercise, either for class or Action Center, in which each student answers a Guided Reading Question or completes a concept map and then a neighbor “grades” it. That way, they can get practice using an at-home resource and get quick feedback on how they’re doing.

Next time, I’ll share the answers to questions 2 and 3. In the meantime, what are your students’ obstacles, and what are your best ideas for helping students to overcome them?

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FOH: Finally, a cure for FMOOWMP

If your students are like mine, no location on campus is scarier than your office. Did you know that their reluctance to come to your office hours actually has a medical cause? I didn’t until I saw this funny new video from Arizona State University, which explains that many students suffer from a disorder called FMOOWMP, or Fear of Meeting One on One With My Professor. fmoowmp-screenshot

Just like in a commercial for a real pharmaceutical drug, students in the video ask questions, like “Is it dangerous?” and “How did I even get FMOOWMP?” Then, the video proposes a treatment: FOH, or Faculty Office Hours. More questions from students ensue: “Do I need a prescription?” and “Does it hurt?” and “Is it habit-forming?” The commercial ends with testimonials by students who have successfully undergone treatment for FMOOWMP, followed by the obligatory list of side effects (I won’t spoil it for you). The fast-talking disclaimer at the end is worth listening to as well.

I played this video for my class a couple of weeks ago, and I was amazed to see its impact. Suddenly, students started  showing up for my office hours, after weeks of fruitless cajoling on my part. They admitted that the video had played a role in their decision to come in and talk to me. Try it for your own classes — perhaps it will be just what the doctor ordered for you, too.

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Flashcards, but with a Twist

I have had a fondness for index cards for quite a few years, if my 2012 series on the subject is any indication (for a flashback, visit part 1, part 2, and part 3). Flashcards are of course a tried and true way to use index cards, and I thought I knew just about everything there was to know about the subject.

regular-cards

Regular old flashcards. Photo by M. Hoefnagels.

But a friend of mine recently drew my attention to a blog post illustrating a fantastic way to use flashcards: Be Your Own Teacher: How to Study with Flashcards. That link describes the technique perfectly, so you don’t really need to keep reading here anymore, but I’ll go ahead and describe my brief but wonderful experience with the technique.

First, a summary: The main idea is to make TWO sets of cards. The first set consists of traditional cards with a term on one side and a definition on the back. Ho hum. But the second set is where the magic happens. This set is much smaller, and it consists of some generic questions.

generic-questions

Boom! These questions make regular flashcards awesome. Photo by Laura Bartley.

I stole many of my generic questions from the Be Your Own Teacher blog post I referenced above, but I added a couple myself. Here are the ones I used:

  • Describe this concept without using any key words written on the flashcard.
  • Draw this concept.
  • Give a real life example of this concept.
  • How would you explain this to a child/someone who has never heard of it before?
  • What is the opposite of this concept?
  • Why is knowledge of this concept useful to you?
  • How does this concept relate to any other flashcard in your stack?
  • Where does this concept fit in the organizational hierarchy of life?

The student shuffles both sets of cards separately and then pulls one card from each deck. That means that a flashcard with, say, the definition of nucleotide is now paired with one of the thought-provoking questions listed here. As if by magic, the flashcard is transformed from a tool that promotes memorization into a tool that promotes thinking. The best part is that those question cards can be used for any topic in my biology class. Genius!

I used this technique on a couple of sets of students in my Action Center yesterday, and the response was very positive. The Peer Learning Assistant who runs the Action Center with me was also impressed, although she was also a little bit dismayed that all of the “go-to” questions that she uses to interact with clients could be summed up in eight little index cards.

I am trying to think of more questions to add to my set. If you have a good idea, please add a comment to this post.

 

 

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The “Checks”/”Emails” lab: a good start to the semester

Checks and their corresponding emails, side by side. Photo by M. Hoefnagels.

Checks and their corresponding emails, side by side. Photo by M. Hoefnagels.

We just finished our first week of classes at the University of Oklahoma, and my nonmajors students trooped dutifully into lab on Tuesday and Thursday afternoons. To get them talking to each other, one of the icebreaker activities we have done for many years is the “Checks lab,” a lesson on the nature of science. According to the Checks lab page, the activity was originally developed in 1992 by Steve Randak and was modified in 1999 by Judy Loundagin.

In case you’re not familiar with this activity, here’s a summary. Each team of students is given an envelope containing copies of 16-17 checks that are made out to various payees. Students are told to withdraw four checks at random and propose a scenario that could account for the checks. They then withdraw four more and revise their scenario to account for the new information. After one more round of withdrawing two more checks, they aren’t allowed to see any more checks. At that point, the class as a whole comes together to figure out what actually happened to the people writing the checks.

Since each team sees a different subset of the checks, and no one sees them all, students may not agree on what happened and when. Depending on how deep the instructor wants to go into the nature of science, the ensuing discussion can go in any number of directions. To me, the main points are that scientists never get 100% complete information, that other researchers may have information that your group doesn’t have, and that collaboration is a valuable way to get as much of the story as possible. The website where I found this activity has a huge number of ideas for expanding on these and many others when teaching about the nature of science; I recommend it.

Over the summer, however, I got to thinking about whether students these days actually write checks (or know what they are). I did some asking around, and it turns out that they do—but they don’t write nearly as many as we did in our youth. They buy a lot of things online, and even when they pay for something in person, they are likely to use a debit or credit card. So the trusty old “checks lab” seems a bit outdated.

Apparently I am not the only one who thinks so, because Judith Lederman and her colleagues published an updated version in The Science Teacher for September 2015, 82(6):57-61. This new version includes copies of emails instead of checks. Hurray! The emails themselves have been posted to NSTA’s The Science Teacher Connections, Sept. 2015 edition; here’s a direct link to the Word document they provide at that site.

Matt Taylor has upped the ante a little bit more: He turned the Word document into a PowerPoint (to be printed at four slides per sheet) that has a reduced emphasis on the AOL and hotmail logos. We used these mock emails in our labs last week, and they worked great; if you would like me to email you a copy, please write a comment in this blog post. In the meantime, kudos to all who developed, modified, and shared this activity.

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HHMI Biointeractive Workshops at Tulsa Community College

Below is a flyer for a couple of excellent HHMI workshops that Tulsa Community College is hosting from October 6-7.

From the event coordinator: Faculty, TA’s and graduate students are encouraged to attend. Excellent workshops and networking! 

Please RSVP early by clicking here.

HHMI 2016

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