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TPO 21

Conversation 1

Narrator

Listen to a conversation between a student and a professor.

Professor

Excuse me, can I help you? You look a little lost.

Student

Yeah, I am. This is my first day on campus, and I don’t know where anything is.

Professor

Can’t find your orientation session?

Student

Uh-huh. What a way to begin! Lost going to orientation

Professor

Well, my guess is in the auditorium, that’s where they usually are.

Student

You’re right, the general ones. I went to one of those sessions earlier today. But now I need the one for my major, engineering. My schedule says the meeting room is in ... Johnson Hall? In the engineering department, which should be right here in front of us, according to the map? But this building is called the Morgan Hall.

Professor

Well, your map reading skills are fine actually. This used to be Johnson Hall, all right. Trouble is they changed the name to Morgan Hall last spring. So they sent you a map with an old name? I am surprised.

Student

Well, this was actually mailed out month and month ago. I got a second pack in the mail more recently with another one of these maps in it. I guess they must have the updated name. I left that one in my dorm room.

Professor

Well, things change fast around here. This building was renamed after one of our professors. She retired a few months ago. She is very well-known in the world of physics. Too bad for Johnson, I guess.

Student

Who is Johnson anyway?

Professor

Oh, one of the early professors here. Unfortunately, I think his ideas are going out of style. Science kept marching forward.

Student

I’ll say it does. That’s why I transferred to this university. I was really impressed with all the research equipment you guys have at the laboratories. You are really on the forefront.

Professor

Um... so do you know what kind of engineering you want to specialize in?

Student

Yeah, aerospace engineering.

Professor

Well, the aerospace engineering department here is excellent! Eh... do you know that this university was the first one in the country to offer a program in aerospace engineering?

Student

Yeah, I know. And a couple of students who graduated from here became astronauts and orbited the Earth.

Professor

Right. The department has many prominent alumni. Well, you might end up taking some of your advanced math course with me. I get a lot of students from the engineering department because I teach the required applied mathematics courses.

Student

Oh, cool. Actually, I want to get a minor in math.

Professor

Excellent. Hmm... A major in aerospace engineering with a minor in math, you’ll go far with that degree. More of our students should do that. There are so many more opportunities available in the field when you have a strong math background.

Student

I’m glad to hear you say that.

【Lecture 1】

Astronomy (Geocentric & Heliocentric theory)

Narrator Listen to part of a lecture in a history of science class. Aristarchus-Heliocentric Theory

Professor

Ok, we have been talking about how throughout history, it was often difficult for people to give up ideas which have long been taken for granted as scientific truth, even if those ideas were false. In Astronomy, for example, the distinction between the solar system and the universe wasn’t clear until modern times. The ancient Greeks believed that what we called the solar system was in fact the entire universe, and that the universe was geocentric. Geocentric means Earth-centered, so the geocentric view holds that the Sun, the planets, and the stars, all revolve around the Earth, which is stationary. Of course, we now know that the planets, including Earth, revolve around the Sun, and that the solar system is only a tiny part of the universe.

So, why did the ancient Greeks believe that the Earth was the center of the universe? Well, it made sense to them. Observations of the sky make it appear as if the Sun, the moon, and the stars all revolve around the Earth everyday, while the Earth itself stayed in one place. And this view is also supported by their philosophical and religious beliefs about the origin and structure of the universe. It was presented in the works of well-known Greek philosophers as early as the fourth century B.C.E., and the geocentric theory continue to prevail in Western thought for almost 2,000 years, until the 17th century.

Now, what’s especially interesting is that when astronomical observations were made that seemed to be inconsistent with the geocentric view, the ancient Greeks did not really consider alternative theories. It was so intuitive, so sensible that the Earth was the center of the universe that astronomers found ways to explain those seemingly inconsistent phenomena within the geocentric view.

For example, Greek astronomers made excellent, very accurate observations of the movements of the planets, but the observations revealed a bit of a problem. The geocentric theory said that the planets would move around the Earth in one direction. However, astronomers noticed that at times, several planets seem to stop moving in one direction and start moving backward in their orbits around the Earth, and they came up with a theory that these planets themselves moved in smaller circles called epicycles as they travelled around the Earth. Here’s a picture of what they imagined. You see how this epicycle theory could account for the seemingly backward motion of the planet. Of course, today we know that this appearance of backward motion is caused by the fact that Earth, as well as other planets, all move in their own orbits around the Sun, and the relative movements of the planets with respect to each other can get quite complex.

However, there were a few astronomers in Greece and other places who didn’t agree with the geocentric view, for example, a Greek astronomer who lived in the third century B.C.E. He proposed the theory that our planetary system might be heliocentric, his name was Aristarchus. Heliocentric means Sun-centered, that the Earth revolves around the Sun. Aristarchus recognized from his calculations that the Sun was much larger than the Earth and other planets. It was probably this discovery that led him to conclude that the universe is heliocentric. I mean, isn’t it more sensible to think that a smaller heavenly body would orbit a larger one, rather than the opposite?

However, his proposition was rejected largely based on other scientific beliefs held at the time, which all made sense in a way even if they were incorrect. Let me mention two objections Greeks made to Aristarchus’s theory. First, they believe that everything that moves creates its own wind; so to speak, everyone has this experience when you are running, right? So, they thought that if the Earth itself was moving, there would have to be a constant wind blowing, sweeping them off their feet, and of course there wasn’t. And second, the idea of an Earth that moved didn’t fit in with the ancient Greeks’ understanding of gravity. They thought that gravity was basically a natural tendency of all things to move towards the center of the universe, which was the Earth, or the center of the Earth, so that explains why apples and other falling objects were falling straight down. If the Sun was at the center of the universe, things would fall toward the Sun and away from the Earth, which of course they didn’t. So these were some of the reasons they rejected the heliocentric theory.

【Lecture 2】

Computer Science (Software Development)

Narrator Listen to part of a lecture in a Computer Science class. The professor is discussing software engineering.

Professor We’ve been talking about the software development cycle, and today I’d like to move on to the next stage of that cycle-testing, and why finding bugs during testing is actually a great thing. Eh...eh... the quality of the software product often relies heavily on how well it’s been tested. Liz?

Student Um... just a quick thing. Bugs are the word for problems in the program code, right?

Professor

Yeah, in code or in a computer itself. There is a bit of a story behind that term. Um... back in the 1940s, when the computer industry was just starting, a group of computer scientists was working late one night, and there was a problem in one of the computers’ circuits1. When they examined it, they found a five-centimeter long moth caught in there. Once they debugged the computer, it worked just fine. And ever since then, all kinds of computer problems have been known as bugs.

Anyway, you want to find bugs while the software is still in the development and testing phases. Finding them when the software product has already been put on the market can be quite embarrassing. Generally speaking, every software development project has a group of testers and a group of developers. Jack?

Student

And they are different people?

Professor

They are generally completely different group of people. My personal opinion is that they have to be different groups of people because developers often have a bias for their own work, and it blinds them to certain problems that might be obvious to somebody else. So it is always good to have a different set of eyes to go in there and make sure that everything is tested properly.

Ok, now, here’s the key. Developers and testers have different mentalities. The mentality of the software developer is constructive, creative, they are spending long hours working together to create and build something new. A software tester, on the other hand, their entire goal is to look at this product and find problems with it, to improve it. Now, this difference between the testers and the developers can lead to an environment where there is a bit of friction. And that friction sometimes makes it difficult for the two teams to work together.

There are two projects that I worked on a couple of years ago. One, which I’ll call Project Split, well, the testing and development teams did not work well together. And the other, I’ll call Project Unity, during which both teams worked very well together. Now, during Project Split, we had defect meetings where the developers and the testers met together, eh... eh... to discuss various problems and how they should be fixed. And you could sense the conflict just by walking into the room. Literally, the testers and the developers sat on opposite sides on the table. Um... and ... and the developers were very defensive about the feedback.

Student Well, if bugs are being pointed out they wouldn’t be too happy since it’s their work.

Professor

Exactly. Now, ‘because the two teams weren’t working well together, the fixes were coming very slowly. And you know, a lot of times when you fix bugs you introduce new bugs, or you discover bugs and other areas that only come to light because something has been changed, so fixing all those new additional bugs was also being delayed. Um... the test process went on much longer than expected and we ended up having to put the product on the market with known bugs in it, which was obviously not ideal.

Student

Ok and what about Project Unity? How was it different?

Professor

Um... this was different because two teams worked closely together during the defect meetings, instead of put up walls. Um... we didn’t even talk about, you know, who should fix this, which is at fault2. We all acknowledge what needed to be fixed. So if we had ten bugs, we said, ‘Hey, you know what? Let’s do this one first ‘cause this would expose another whole bunch of defects that we haven’t even seen yet.’ So we were being proactive3 and effective. And because we were so much more effective with our time, we were actually able to do more than just fix the bugs; we even put in some improvements that we hadn’t planned.

Conversation 2

Narrator Listen to a conversation between a student and her public relations professor.

Student

Hi, professor Gordin. I really learned a lot from your lecture, the one about analyzing all those different segments of the population. Oh, the official term is audience, right? I never imagine that one company could have over thirty audiences to communicate with.

Professor

Yeah, a lot of students are taken aback by this, and some public relations consultants don’t figure it out until they’ve worked in the field a while.

Student

Everyone thinks, public relations, eh, PR is easy, but there’s a lot to it. You really got to know what you are doing.

Professor

Absolutely. So, Stacy, your email implied that you needed my advice about graduate school?

Student

No, since my undergraduate degree will be in public relations, I’ve already decided to get a master’s degree in marketing. Sorry, I wasn’t clear. My issue is, I have got two require courses and two electives. I am trying to figure out which elective course is to take. My advisor suggested economics and accounting, but I am not really sure.

Professor About?

Student

Well, I endured accounting and economics in high school and barely stayed awake, they were so ...

Professor

Ok, Ok. I hear you. Eh... you say you wanted a master’s in marketing, you have got one more semester till graduation. Have you taken any marketing courses yet?

Student

No, I figured I’ve got the marketing basis already since I have taken every PR in communication courses offered here.

Professor

Well, there’s some overlap between PR and marketing, but there are important differences too. Marketing focuses on selling your product or service, eh, you know, attracting customers through advertising, and also buiding relationships with customers. That’s what a marketing department does. PR is all about, it involves relationships too, that’s why I am saying the two fields overlap. But in PR, you are developing relationships with a wider range of audience.

Student

Right. Like employees, suppliers, the media. I do understand this in theory, but aren’t you still selling your product, just in a different way?

Professor

Not necessarily. Ok, do you remember that PR strategy I alluded to the other day? The one our university uses, a strategy that doesn’t overlap its marketing strategy?

Student

You mean how the university invites local residents to attend certain lectures and classes for free?

Professor

Yeah, this cultivates a sense of good will and helps the university avoid becoming isolated from the larger community. Bringing neighbours into our classrooms is good PR, but it is not marketing since our neighbours aren’t our customers, for the most part.

Student

That’s why I want to focus on marketing in graduate school. Wouldn’t having expertise in PR and marketing giving me more career options?

Professor

Yeah, but you’ll also want to enjoy your work. So for you electives, why don’t you take advertising principles and intro to marketing, which I teach. This way, you’ll find out if marketing is something you really want to pursue. Graduate School tuition is expensive, and these courses will give you a good overview of the field before committing yourself.

Student

I wish my advisor had suggested those courses.

Professor

Well, I am someone who has worked in both marketing and PR, so I can offer a different perspective than someone who only teaches ...

【Lecture 3】

Biology (Snake Evolution)

Narrator Listen to part of a lecture in a biology class.

Professor Probably back in some previous biology course you learned that snakes evolved from lizards, and that the first snakes weren’t venomous and then along came more advanced snakes, the venomous snakes. Ok, venomous snakes are the ones that secrete poisonous substances or venom, like the snakes of the viper family or cobras. Then there is non-venomous snakes like constrictors and pythons. Another family of snakes, the colubrids, don’t really fit neatly into either category though. Colubrids, and you probably learned this too, although they are often classified as venomous snakes, they are actually generally non-venomous. They are classified as venomous snakes because they resemble them, their advanced features more than the other non-venomous snakes.

Now, what if I told you that there is a good chance that most everything I just said is wrong? Well, everything except the part about snakes evolving from lizards. See, the basic theory about snake evolution has been challenged by a recent study that revealed a whole new understanding of evolutionary relationship for reptiles, you know, which reptiles descended from which ancestors. The researchers study the proteins in the venom genes of various species of colubrids. Emm... snake venom is a mixture of proteins, some toxic, poisonous, and some not. By analyzing the DNA, the genetic material of the proteins, the researchers could focus on the toxic genes and use them to trace the evolution of snake venom, and from this, the evolution of snakes.

Traditionally, to understanding evolutionary relationships, we looked at various easily observed physical characteristics of animals, their skeleton, the size of their brain, and... And then classify them based on similarities and differences. The problem with this method is that characteristics that appear similar may actually have developed in quite different ways. For example, some venom are chemical-based, and others are bacteria-based, so they clearly had to have developed along different routes and may not be as closely related as we thought.

Now, and not everyone will agree about this. The classification based on DNA seems to be much more reliable. Ok, back to the research. The researchers found that venom evolved before snakes even existed, about a hundred million years before. Now, a couple of venomous lizards were included in this study. And the researchers found some of the same DNA in their venom as in the snakes’ venom. This suggested that the common ancestor of all snakes was actually venomous lizard, which means that actually, according to this research, anyway, in terms of the snakes’ ancestry, there is no such thing as a non-venomous snake, not even colubrids. What separates colubrids from other snakes we have been classifying is venomous, is not the lack of venom, but the lack of an effective way to deliver the venom into its prey. In most venomous snakes, like vipers and cobras, the venom is used to catch and immobilize the prey; but in colubrids, venom drips onto the prey only after the prey is in the snake’s mouth. So for colubrids, the venom must serve some other purpose, maybe linked to digesting prey. As the different families of venomous snakes evolved, the teeth moved forward, becoming larger, and the venom becoming stronger, so the evolution of the obvious venomous snakes, like cobras and vipers, is about the evolution of an efficient delivery system, not so much the evolution of the venom itself.

So, if there are no truly non-venomous snakes, were the so-called non-venomous snakes, like constrictors and pythons, were they venomous at some point in their evolution? Well, that’s not clear at this point. Constrictors have evolved to kill their prey by crushing, but perhaps they once were venomous, and then at some point their venom-producing apparatus4 wasn’t needed anymore, so it gradually disappeared. There’s one species of snake, the brown tree snake that uses both constriction and venom, depending on its prey. So, well, it is possible.

So, we have these new concepts of snakes’ evolution and a new DNA database, all these information on the genetic makeup of snake venom. And what we have learned from this has led researchers to believe that venom proteins may have some exciting applications in the field of medical research. You see, venom alters biological functions in the same way certain drugs do, and the big benefit of drugs made from snakes venom would be that they target only certain cells, so maybe that’ll create fewer side effects. Now, it sounds far-fetched5, venom is the basis for human drugs. So far, only one protein has been targeted for study as a potential drug, but who knows, maybe someday.

【Lecture 4】

Art History (Alice Neel)

Narrator Listen to part of a lecture in an Art History class.

Professor

All right, so today we are moving on to Alice Neel, N-E-E-L. Um... Alice Neel painted portraits, she was born in Pennsylvania, and she lived from 1900 to 1984. And I guess you might say, she experienced difficulties as an artist. She was in her 70s, before she had her first major solo exhibition. Um, and this is due at least in part to eh... or... because of photography. After photography became regarded as an art form portrait painting became less prestigious, less respected as an art form. And, well, art photography kind of took its place, so you can imagine that a portrait artist would have had a hard time finding acceptance.

Eh, but the real reason I want to look at Neel, is that I really find her style ... eh, she had interesting ways of portraying people. She combined some elements of realism. What’s realism, Alison?

Student

It’s like painting something exactly how it is, so an artist would try to make it as accurate, um... and objective as possible. Painting stuff just how it appears on the surface.

Professor

Ok, good. So Neel combined realism with, well, actually, with expressionism. And that is? We, we just covered this.

Student

Um... It’s into emotion, like artists are trying to, well, express themselves through the painting, right?

Professor

Yep. The artist is depicting subjective emotions, showing the inner reality as interpreted by the artist rather than the outward form. So the image itself might be distorted or exaggerated in some way. The expression overrides objective representation. Ok, so, Alice Neel combined these two styles ... Yes?

Student

Em... How is that even possible? How can your portray something exactly as it is and at the same time distort it with emotions? I don’t get it.

Professor

All right, good question. It is actually a good lead-in8 to some of the techniques that Neel used, that she employed to bridge that contradiction. In a minute, I’ll show you some of her portraits, and I’ll want you to notice a few things about them.

First, Neel’s use of bold color. All right? You’ll see she uses color to convey emotion and feeling, like the subjects’ clothing for instance, it appears brighter than it really is. And the subjects, the people being portrayed, Neel paid special attention to faces. The way she paints the eyes and how the faces are portrayed, these are quite realistic, like the realists’ work. But another thing Neel did was use elongated, sort of stretchy figures.

Student

But didn’t a lot of expressionist painters do that? So really your are saying that Neel’s techniques were similar to what other artists were doing. What was it that she did, that was like all her own?

Professor

Ok, well, I think it has to do partly with the way she combined these techniques. So, for example, those realistic faces and eyes, but bright, distorted figures. It is a mix. You’ll see that her portraits do reflect reality, the people that were actually sitting there. Realism was important in the sense that she wanted to show people as they really were, much like a photographer would. But Neel wasn’t satisfied with photo-like realism, she went beyond that. And this is where expressionism comes in.

She believed in capturing the whole person, not just what was on the surface, that’s where the expressionists’ distortion is important, in an attempt to reveal the subjects’ character or personality.

But Neel’s paintings are distinctive for her time in part because they are portraits. Remember I said that photography and art photography had largely taken the place of portraiture, to the extent that some critics had declared the genre of portraiture to be dead. But Neel felt that painting should reflect reality, a real realist’s stance9 you could say. And to her, individuals, people best reflect the reality of their time, of the age that they lived in, so she painted portraits. And if you look at her work, we are talking in the vicinity of10 three thousand paintings. If you’re looked at them, it is like this gallery of the whole century, an enormous range of subjects: families, women, children, artists, and people in poverty--these paintings really span class, age and gender. It is like she transformed the genre, it is not just formal depictions of presidents and ancestors any more.

But keep in mind that she was doing this when abstract art dominated the art scene. Representations of people weren’t fashionable in the art world. And it wasn’t until fairly late in the century that critic recognized the power of what she did.