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Using KDE/Comparisons

KDE and GNOME

 * In terms of the basic desktop layout, KDE more-closely follows a Microsoft Windows style with a taskbar, start menu, and various other things. On the other hand, GNOME takes the Mac OS X approach, placing the menu bar on top of the screen and a separate bar for currently-open applications (the Task Bar).
 * KDE and GNOME each have their own set of usability and accessibility guidelines:
 * KDE Human Interface Guidelines
 * GNOME Human Interface Guidelines
 * KDE is built with the Qt toolkit while GNOME uses GTK.
 * KDE is written in C++ and GNOME in C.
 * While GTK is a very popular toolkit for Linux and thus most apps have better integration with GNOME, KDE's interface is normally considered slicker and more polished, possibly due to the underlying Qt toolkit.

title: Using KDE/Comparisons


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User talk:Marsian~enwikibooks

Hey Marsian,

Thanks for your corrections on the Japanese wiki! If you correct the Japanese, don't mark the change as minor. The Japanese is the most important thing on the page!

P.S. Where are you from? 何弁でしょうか.

-ToothingLummox 15:30, 27 August 2005 (UTC)

 * Hello. All right, I won't check "minor" when I fix (forgive me please when I forget).

 * I'm from a small city in 北海道 (not Sapporo). Thus I can speak 北海道弁 a little :) 「...だべや」 or 「わや (very)」 or... kind of that. Where are you from, ToothingLummox? Aren't you a Japanese? No? まぁそうだったらそうだったで，英語で会話する日本人同士ってのもなんか変な感じがしますが... - Marsian / talk 16:42:14, 2005-08-27 (UTC)

 * 私は日本人じゃないですから、 no need to worry about 変な感. I'm an American from near Washington, DC. I spent a few years in Japan (「英語分からへん」or 「○○先生いひん？」 or「靴下投げんといて！」or (from an actual lesson) "It's a dog" =「犬やで」), but I still make plenty of Japanese mistakes. Your corrections to the Japanese Wikibook are much appreciated.  You're more than welcome to do it again sometime. -ToothingLummox 13:24, 29 August 2005 (UTC)

 * I see. So you've been to Kansai or western Japanese. I myself have several friends from Kansai and mostly Kyushu and I like Kagoshima-ben much. I'm glad if my edits and/or comments improve the Book, thanks (but remember, anytime you can say to me 「ちょ、ほんまやかましいわ自分. 黙っとき」 or like that :). - Marsian / talk 17:12:48, 2005-08-29 (UTC)

English Corrections
I just wanted to point out that some of the corrections I made were more stylistic than grammatical. A lot of "learner language" falls into a gray area; it's not really wrong but it's not how most native speakers would say it. Anyway, since you don't actively study English, make sure that you actively pay attention when you encounter it. :)

-ToothingLummox 08:20, 9 October 2005 (UTC)

 * All right... You know, your corrections are really helpful to(for?) me. I think I've got to pay back (by editing the Japanese book :). Thanks again. - 08:59, 13 October 2005 (UTC)

第三夜
If you have time coluld you please check Japanese:Reader:第三夜 for any mistakes. Thanks, Gmcfoley 19:57, 31 October 2005 (UTC)
 * Hi. I left my comments on the Talk:. - Marsian / talk 04:44, 1 November 2005 (UTC)

Thanks, very much! Your comments were very enjoyable to read, I hope you will be able to check the page every so often. Gmcfoley 21:34, 1 November 2005 (UTC)
 * 六つ: This was a stupid mistake. It should have been むっつ, not むつ.
 * 1) As for the obsolete kanji and obsolete readings, the story is approx. 100 years old, so it will probably contain things that are no longer used. I think that it would be cool to keep them, but I added a note beside those words.
 * 2) The purpose of this page is to give people the chance to practice reading real Japanese, with all the words and grammar explained on the same page.

re Thanks for the rollbacks
It was a vandal bot, it appears it was programmed to attack until it was blocked and then move on. It hit Wikipedia,Wiktionary,Wikibooks,Meta, and Wikiquote, in that order.It may have continued on to other Wikis, but Brion blocked it WMF wide.--Cspurrier 23:13, 10 February 2006 (UTC)

 * Oh, I didn't notice that. Thanks anyway. - Marsian / talk 11:43, 11 February 2006 (UTC)

みんでぃです
ウィキテク（Howto Wiki）のみんでぃです. ご無沙汰して、すみません. Maz, thank you for the comment! I have write you back.

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Marsian. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Marsian~enwikibooks that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:25, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 05:14, 19 April 2015 (UTC)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: User talk:Marsian~enwikibooks


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User:Herblady

Location: Florida/USA, native German Occupation: Umweltberater / Environmental Consultant studied Chemistry/Biology/Psycholoy/Environmental Consulting and some more age: too old planning to contribute to the how to book section especially starting with   have some other ideas but little time: for example

title: User:Herblady


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Category:Book:Trigonometry

es:Categoría:Trigonometría it:Categoria:Trigonometria pt:Categoria:Trigonometria

title: Category:Book:Trigonometry


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User:Munchkinguy

Hello! Currently, the only thing I am working on is making PDF versions of different books in Wikijunior.

See my Wikipedia user page.

title: User:Munchkinguy


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Muggles' Guide to Harry Potter/Characters/Sorting Hat

Overview
The Sorting Hat is described as being very old and patched. When the hat is put on the head of a Hogwarts new arrival, a mouth forms at the brim, and the hat states, for all to hear, which of the four school Houses the child wearing it belongs in: Gryffindor, Hufflepuff, Ravenclaw, or Slytherin.

The Sorting Hat also sings a song for all of the Hogwarts students and staff before the beginning-of-the-year feast, describing its job and the four Hogwarts houses. However, when the wizarding world or the school is in any imminent danger, the hat will also sing about the importance of the four houses standing together as brothers and sisters in the fight against evil.

The Sorting Hat's unusual qualities are due to the fact that Godric Gryffindor, one of the four Hogwarts founders, owned the hat, and knowing that he would not be around to select houses for the incoming students forever, placed a charm on it to do its job.

Philosopher's Stone
In this book, the Sorting Hat was introduced as the means through which students are sorted into their respective houses.

Having sung its song, it was then placed on the head of each of the first-year students in turn. It then assigned each to a house. The Hat initially though that Harry would do well in Slytherin, but Harry told it that he didn't want to go to Slytherin. The hat then placed him in Gryffindor.

Chamber of Secrets
Because they were unable to make it onto the Hogwarts Express, Harry and Ron are still outside the school when the Sorting commences. They see some of the Sorting proceeding through the window of the Great Hall, but are not present for the Sorting Hat's song.

Later in the book, where Harry is summoned to Professor Dumbledore's office, he finds himself alone in the office with the Sorting Hat and decides to see if the Hat had had second thoughts about his Sorting. The Sorting Hat tells Harry again that he would have been great in Slytherin; Harry disagrees rather forcefully.

In the climactic battle against the Monster in the chamber, Fawkes the phoenix drops the Sorting Hat at Harry's feet; Harry thinks this is useless, though he wears it in hopes that it might afford him some protection or at least counsel; and it shortly thereafter presents him with a sword. Harry uses the sword to kill the basilisk (the Monster).

Harry, having told all this to Professor Dumbledore, tells Dumbledore that the Sorting Hat had originally wanted to place Harry in Slytherin. Dumbledore asks Harry why it did not; Harry says that he had asked it not to. Dumbledore points out that "it is our choices, Harry, that show what we truly are, far more than our abilities." Dumbledore then tells Harry that if he still wonders, he should examine the sword. Harry finds that it is the sword of Godric Gryffindor. Dumbledore tells him that only a true Gryffindor could have pulled that sword out of the Hat.

Prisoner of Azkaban
News that Harry had reacted strongly to the Dementor had been sent to the school by Owl ahead of time, so Harry is taken aside into Professor McGonagall's office so he can be checked over by Madam Pomfrey. Professor McGonagall also wants a word with Hermione Granger and so draws her aside as well. As a result, when Harry reaches the Great Hall, the Sorting is finished, and all we see of the Sorting Hat is Professor Flitwick removing it and its three-legged stool from the stage.

Goblet of Fire
Before the Sorting, the Hat again sings a song about the history of Hogwarts. Harry notes that it is a different song than the one he had heard his first year there, and Ron says that it is a different song every year. Being a hat, it can't have much to do most of the time, and so Ron surmises that it has a lot of time to make up its song.

Order of the Phoenix
Prior to the Sorting, the Hat sings a very much longer song than usual, specifically going into the history of Hogwarts and its founders, and the divisiveness that resulted. It ends with a plea for the four houses to work together in this time of trouble. Ron asks Nearly Headless Nick if the Hat has been known to sing in support of unity, and Nick replies that it has done so quite often, though he is interrupted by the Sorting. Once all the students have been Sorted, he continues that the Hat, being in the Headmaster's office almost all of the time, is aware of what is happening in the school and things that affect the school, and if it sees a problem will try, as best it can, to draw attention to it.

Half-Blood Prince
Due to the argument with Draco Malfoy on the Hogwarts Express, Harry arrives at the feast not only after the Sorting, but largely after the Feast has finished. As a result, we do not see the Sorting Hat at all in this book, except in passing when Harry, visiting the Headmaster's office, notices it sitting quietly on the shelf.

Deathly Hallows
In Severus Snape's memories, we see the Sorting Hat as it Sorts Lily Evans, Peter Pettigrew, and James Potter into Gryffindor, and Snape into Slytherin.

At the Battle of Hogwarts, Neville Longbottom is forced by Voldemort to wear the Sorting Hat. Voldemort then sets Neville on fire, but Neville is unhurt by Voldemort's curse, and pulls the Sword of Gryffindor from the Sorting Hat, just as Harry did in the Chamber of Secrets. Neville then kills Voldemort's snake Nagini, the last of Voldemort's Horcruxes, making it possible for Voldemort to later die from his own reflected killing curse.

In the Epilogue the Sorting Hat is mentioned, still doing its job at Hogwarts 19 years later. Harry here tells his son, Albus Severus, that he had asked the Hat not to put him in Slytherin, and it had placed him in Gryffindor instead.

Strengths
The Sorting Hat's annual song reflects the issues and concerns of current events. This implies that the hat has some ability, possibly through listening to passing events in the Headmaster's office, to keep up with the changes and threats to Hogwarts, and sufficient consciousness to understand them.

Weaknesses
It is just a hat, and has only a certain amount of "mind-reading" ability and the power of speech. It cannot move, it can influence events around it only by persuasion, and apparently spends most of its time on a shelf in the headmaster's office.

Relationships with Other Characters
The Sorting Hat is designed to act as a proxy for Godric Gryffindor in selecting Houses in the school for students. As such, Gryffindor must have imbued it with some of his own abilities in that regard, and apparently with some rudimentary consciousness.

It is uncertain how it relates to other characters, as the only time we see it responding to other characters is when it is actually physically placed on a character's head. Its being able to sing before the Sorting begins would suggest that it can communicate; we do not choose to speculate as to why it does not. Ron seems to believe that it can hear and understand conversations proceeding in the Headmaster's office, but we never see it responding to the passing scene while it is sitting on the shelf there; the only time we hear it speak is at the Sorting, and when Harry has it on his head.

Analysis
It is clear that the Hat has some level of consciousness; we hear that its song is different every year, and that its song reflects the need to deal with threats against Hogwarts. It also engages in conversation with Harry on two occasions, first when Harry is initially Sorted in Harry Potter and the Philosopher's Stone, and later when Harry dons the Hat in the Headmaster's office in Harry Potter and the Chamber of Secrets. This is why the Hat is listed as a character, rather than as a magical artifact, in this guide. It is also, probably, why Professor Dumbledore says that the Sword of Gryffindor is the only known artifact of Godric Gryffindor; the Sorting Hat was clearly a possession of his, but its consciousness makes it not an artifact but a person.

The Sorting Hat has an apparent affinity for the Sword of Gryffindor, as we see it produce the sword twice during the series; possibly this affinity comes from the fact that both were the property of Godric Gryffindor, and he may have established that particular affinity himself. It also seems the Hat is capable of retrieving the Sword from anywhere, because Griphook the goblin had taken it when Harry, Ron, and Hermione raided Gringotts. Theoretically the sword should have remained in the possession of the Goblins, as Griphook had returned to his old employers at Gringotts, but the Sorting Hat still manages to provide it to Neville at need.


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C++ Programming/Code/Statements/Functions

Functions
A function, which can also be referred to as subroutine, procedure, subprogram or even method, carries out tasks defined by a sequence of statements called a statement block that need only be written once and called by a program as many times as needed to carry out the same task.

Functions may depend on variables passed to them, called arguments, and may pass results of a task on to the caller of the function, this is called the return value.

It is important to note that a function that exists in the global scope can also be called global function and a function that is defined inside a class is called a member function. (The term method is commonly used in other programming languages to refer to things like member functions, but this can lead to confusion in dealing with C++ which supports both virtual and non-virtual dispatch of member functions.)

Declarations
A function must be declared before being used, with a name to identify it, what type of value the function returns and the types of any arguments that are to be passed to it. Parameters must be named and declare what type of value it takes. Parameters should always be passed as const if their arguments are not modified. Usually functions performs actions, so the name should make clear what it does. By using verbs in function names and following other naming conventions programs can be read more naturally.

The next example we define a function named  that returns an integer value   and takes no parameters. The content of the function is called the body of the function. The word  is a keyword. C++ keywords are reserved words, i.e., cannot be used for any purpose other than what they are meant for. On the other hand main is not a keyword and you can use it in many places where a keyword cannot be used (though that is not recommended, as confusion could result).

Normally when calling a function, a program will evaluate and store the arguments, and then call (or branch to) the function's code, and then the function will later return to the caller. While function calls are fast (typically taking much less than a microsecond on modern processors), the overhead can sometimes be significant, particularly if the function is simple and is called many times.

One approach which can be a performance optimization in some situations is to use so-called functions. Marking a function as is a request (sometimes called a hint) to the compiler to consider replacing a call to the function by a copy of the code of that function.

The result is in some ways similar to the use of the #define macro, but as mentioned before, macros can lead to problems since they are not evaluated by the preprocessor. functions do not suffer from the same problems.

If the inlined function is large, this replacement process (known for obvious reasons as "inlining") can lead to "code bloat", leading to bigger (and hence usually slower) code. However, for small functions it can even reduce code size, particularly once a compiler's optimizer runs.

Note that the inlining process requires that the function's definition (including the code) must be available to the compiler. In particular, inline headers that are used from more than one source file must be completely defined within a header file (whereas with regular functions that would be an error).

The most common way to designate that a function is inline is by the use of the keyword. One must keep in mind that compilers can be configured to ignore the keyword and use their own optimizations.

Further considerations are given when dealing with inline member function, this will be covered on the Object-Oriented Programming Chapter.

Parameters and arguments
The function declaration defines its parameters. A parameter is a variable which takes on the meaning of a corresponding argument passed in a call to a function.

An argument represents the value you supply to a function parameter when you call it. The calling code supplies the arguments when it calls the function.

The part of the function declaration that declares the expected parameters is called the parameter list and the part of function call that specifies the arguments is called the argument list.

Many programmers use parameter and argument interchangeably, depending on context to distinguish the meaning. In practice, distinguishing between the two terms is usually unnecessary in order to use them correctly or communicate their use to other programmers. Alternatively, the equivalent terms formal parameter and actual parameter may be used instead of parameter and argument.

Parameters
You can define a function with no parameters, one parameter, or more than one, but to use a call to that function with arguments you must take into consideration what is defined.

Multiple parameters
The syntax for declaring and invoking functions with multiple parameters can be a source of errors. When you write the function definition, you must declare the type of each and every parameter.

It might be tempting to write (int hour, minute), but that format is only legal for variable declarations, not for parameter declarations.

However, you do not have to declare the types of arguments when you call a function. (Indeed, it is an error to attempt to do so).

Example

In this case, the compiler can tell the type of hour and minute by looking at their declarations. It is unnecessary and illegal to include the type when you pass them as arguments..

by pointer
A function may use pass by pointer when the object pointed to might not exist, that is, when you are giving either the address of a real object or NULL. Passing a pointer is not different to passing anything else. Its a parameter the same as any other. The characteristics of the pointer type is what makes it a worth distinguishing.

The passing of a pointer to a function is very similar to passing it as a reference. It is used to avoid the overhead of copying, and the slicing problem (since child classes have a bigger memory footprint that the parent) that can occur when passing base class objects by value. This is also the preferred method in C (for historical reasons), were passing by pointer signifies that wanted to modify the original variable. In C++ it is preferred to use references to pointers and guarantee that the function before dereferencing it, verifies the pointer for validity.

Since a reference is just an alias, it has exactly the same address as what it refers to, as in the following example:

This program will tell you that the pointers are the same, then that they are different, then the same, then different again.

Now might be a good time to reread the section on arrays. If you do not feel like flipping back that far, though, here's a brief recap: Arrays are blocks of memory space.
 * Arrays are similar to pointers, remember?

In the statement above, my_array is an area in memory big enough to hold five s.  To use an element of the array, it must be dereferenced. The third element in the array (remember they're zero-indexed) is my_array[2]. When you write my_array[2], you're actually saying "give me the third integer in the array my_array". Therefore, my_array is an array, but my_array[2] is an.

So let's say you want to pass one of the integers in your array into a function. How do you do it? Simply pass in the dereferenced element, and you'll be fine.
 * Passing a single array element

Example

This program outputs the following:

The int you passed in has value 0 The int you passed in has value 2 The int you passed in has value 4 The int you passed in has value 6 The int you passed in has value 8

This passes array elements just like normal integers, because array elements like my_array[2] are integers.

 * Passing a whole array

Well, we can pass single array elements into a function. But what if we want to pass a whole array? We can not do that directly, but you can treat the array as a pointer.

Example

This will output the following:

The length of the array is 5 Array[0] = 0 Array[1] = 2 Array[2] = 4 Array[3] = 6 Array[4] = 8

As you can see, the array in main is accessed by a pointer. Now here's some important points to realize:
 * Once you pass an array to a function, it is converted to a pointer so that function has no idea how to guess the length of the array. Unless you always use arrays that are the same size, you should always pass in the array length along with the array.
 * You've passed in a POINTER.  my_array is an array, not a pointer.  If you change <tt>array_arg</tt> within the function, <tt>my_array</tt> does not change (i.e., if you set <tt>array_arg</tt> to point to a new array).  But if you change any element of <tt>array_arg</tt>, you're changing the memory space pointed to by <tt>array_arg</tt>, which is the array <tt>my_array</tt>.

by reference
The same concept of references is used when passing variables.

Example

Example2: to swap the values of two integers, we could write:

In the call of this function we give two variables of type int:

The output of this is '9 7'. Draw a stack diagram for this program to convince yourself this is true. If the parameters x and y were declared as regular parameters (without the '&'s), swap would not work. It would modify x and y in function swap only and have no effect on i and j.

When people start passing things like integers by reference, they often try to use an expression as a reference argument. For example:

This is not legal because the expression <tt>j+1</tt> is not a variable — it does not occupy a location that the reference can refer to. It is a little tricky to figure out exactly what kinds of expressions can be passed by reference. For now, a good rule of thumb is that reference arguments have to be variables.

Here we display one of the two common uses of references in function arguments—they allow us to use the conventional syntax of passing an argument by value but manipulate the value in the caller.

However there is a more common use of references in function arguments—they can also be used to pass a handle to a large data structure without making multiple copies of it in the process. Consider the following:

In this simple example we're able to see the differences in pass by value and pass by reference. In this case pass by value just expends a few additional bytes, but imagine for instance if <tt>text</tt> contained the text of an entire book.

The reason why we use a constant reference instead of a reference is the user of this function can assure that the value of the variable passed does not change within the function. We technically call this "const-to-reference".

The ability to pass it by reference keeps us from needing to make a copy of the string and avoids the ugliness of using a pointer.

In some cases, a function requires an array of a specific length to work: Unlike an array changing into a pointer, the  is not a PLAIN array that can be changed into a pointer, but rather a reference to array with 4  s. Therefore, only an array of 4  s, not array of any other length, not pointer to int, can be passed into this function. This helps you prevent buffer overflow errors because the array object is ALWAYS allocated unless you circumvent the type system by casting.
 * Passing an array of fixed-length by using reference

It can be used to pass an array without specifying the number of elements manually: The compiler generates the value of length at compile time, inside the function, n stores the number of elements. However, the use of template generates code bloat.

In C++, a multi-dimensional array cannot be converted to a multi-level pointer, therefore, the code below is invalid: Although an int[10][5] can be converted to an (*int)[5], it cannot be converted to int**. Therefore you may need to hard-code the array bound in the function declaration: To make the function more generic, template and function overloading should be used: The reason for having n and m in the first version is mainly for consistency, and also deal with the case that the array allocated is not used completely. It may also be used for checking buffer overflows by comparing n/m with junk/rubbish.

by value
When we want to write a function which the value of the argument is independent to the passed variable, we use pass-by-value approach.

Output: 10 + 20 = 30

The above example shows a property of pass-by-value, the arguments are copies of the passed variable and only in the scope of the corresponding function. This means that we have to afford the cost of copying. However, this cost is usually considered only for larger and more complex variables. In this case, the values of "a" and "b" are copied to "num1" and "num2" on the function "add". We can see that the value of "num1" is changed in line 3. However, we can also observe that the value of "a" is kept after passed to this function.

Constant Parameters
The keyword <tt>const</tt> can also be used as a guarantee that a function will not modify a value that is passed in. This is really only useful for references and pointers (and not things passed by value), though there's nothing syntactically to prevent the use of <tt>const</tt> for arguments passed by value.

Take for example the following functions:

In the first example we tried to call a non-const method -- <tt>append</tt> -- on an argument passed as a <tt>const</tt> reference, thus breaking our agreement with the caller not to modify it and the compiler will give us an error.

The same is true with <tt>rotate</tt>, but with a <tt>const</tt> pointer in the second example.

Default values
Parameters in C++ functions (including member functions and constructors) can be declared with default values, like this

Then if the function is called with fewer arguments (but enough to specify the arguments without default values), the compiler will assume the default values for the missing arguments at the end. For example, if I call

that will be equivalent to calling In many situations, this saves you from having to define two separate functions that take different numbers of parameters, which are almost identical except for a default value.

The "value" that is given as the default value is often a constant, but may be any valid expression, including a function call that performs arbitrary computation.

Default values can only be given for the last arguments; i.e. you cannot give a default value for a parameter that is followed by a parameter that does not have a default value, since it will never be used.

Once you define the default value for a parameter in a function declaration, you cannot re-define a default value for the same parameter in a later declaration, even if it is the same value.

Ellipsis (...) as a parameter
If the parameter list ends with an ellipsis, it means that the arguments number must be equal or greater than the number of parameters specified. It will in fact create a variadic function, a function of variable arity; that is, one which can take different numbers of arguments.

Composition
Just as with mathematical functions, C++ functions can be composed, meaning that you use one expression as part of another. For example, you can use any expression as an argument to a function:

This statement takes the value of pi, divides it by two and adds the result to the value of angle. The sum is then passed as an argument to the cos function.

You can also take the result of one function and pass it as an argument to another:

This statement finds the log base e of 10 and then raises e to that power. The result gets assigned to x; I hope you know what it is.

Recursion
In programming languages, recursion was first implemented in Lisp on the basis of a mathematical concept that existed earlier on, it is a concept that allows us to break down a problem into one or more subproblems that are similar in form to the original problem, in this case, of having a function call itself in some circumstances. It is generally distinguished from iterators or loops.

A simple example of a recursive function is:

It should be noted that non-terminating recursive functions as shown above are almost never used in programs (indeed, some definitions of recursion would exclude such non-terminating definitions). A terminating condition is used to prevent infinite recursion.

 * Example:

The above function can be called like this:

Why is recursion useful? Although, theoretically, anything possible by recursion is also possible by iteration (that is, ), it is sometimes much more convenient to use recursion. Recursive code happens to be much easier to follow as in the example below. The problem with recursive code is that it takes too much memory. Since the function is called many times, without the data from the calling function removed, memory requirements increase significantly. But often the simplicity and elegance of recursive code overrules the memory requirements.

The classic example of recursion is the factorial: $$n!=(n-1)!n$$, where $$0!=1$$ by convention. In recursion, this function can be succinctly defined as

With iteration, the logic is harder to see:

Although recursion tends to be slightly slower than iteration, it should be used where using iteration would yield long, difficult-to-understand code. Also, keep in mind that recursive functions take up additional memory (on the stack) for each level. Thus they can run out of memory where an iterative approach may just use constant memory.

Each recursive function needs to have a Base Case. A base case is where the recursive function stops calling itself and returns a value. The value returned is (hopefully) the desired value.

For the previous example,

the base case is reached when $$n=0$$. In this example, the base case is everything contained in the else statement (which happens to return the number 1). The overall value that is returned is every value from $$n$$ to $$0$$ multiplied together. So, suppose we call the function and pass it the value $$3$$. The function then does the math $$3*2*1=6$$ and returns 6 as the result of calling factorial(3).

Another classic example of recursion is the sequence of Fibonacci numbers:

0 1 1 2 3 5 8 13 21 34 ...

The zeroth element of the sequence is 0. The next element is 1. Any other number of this series is the sum of the two elements coming before it. As an exercise, write a function that returns the nth Fibonacci number using recursion.

main
The function <tt>main</tt> also happens to be the entry point of any (standard-compliant) C++ program and must be defined. The compiler arranges for the <tt>main</tt> function to be called when the program begins execution. <tt>main</tt> may call other functions which may call yet other functions.

The <tt>main</tt> function returns an integer value. In certain systems, this value is interpreted as a success/failure code. The return value of zero signifies a successful completion of the program. Any non-zero value is considered a failure. Unlike other functions, if control reaches the end of <tt>main</tt>, an implicit  for success is automatically added. To make return values from <tt>main</tt> more readable, the header file <tt>cstdlib</tt> defines the constants <tt>EXIT_SUCCESS</tt> and <tt>EXIT_FAILURE</tt> (to indicate successful/unsuccessful completion respectively).

The main function can also be declared like this:

which defines the <tt>main</tt> function as returning an integer value int and taking two parameters. The first parameter of the <tt>main</tt> function, argc, is an integer value int that specifies the number of arguments passed to the program, while the second, argv, is an array of strings containing the actual arguments. There is almost always at least one argument passed to a program; the name of the program itself is the first argument, <tt>argv[0]</tt>. Other arguments may be passed from the system.

Example

If the program above is compiled into the executable <tt>arguments</tt> and executed from the command line like this in *nix:

$ ./arguments I love chocolate cake

Or in Command Prompt in Windows or MS-DOS:

C:\>arguments I love chocolate cake

It will output the following (but note that argument 0 may not be quite the same as this—it might include a full path, or it might include the program name only, or it might include a relative path, or it might even be empty):

Number of arguments: 5 Argument 0 = './arguments' Argument 1 = 'I'  Argument 2 = 'love' Argument 3 = 'chocolate' Argument 4 = 'cake'

You can see that the command line arguments of the program are stored into the <tt>argv</tt> array, and that <tt>argc</tt> contains the length of that array. This allows you to change the behavior of a program based on the command line arguments passed to it.

Callback
In computer programming, a callback is executable code that is passed as an argument to other code. It allows a lower-level abstraction layer to call a function defined in a higher-level layer. A callback is often back on the level of the original caller.

Usually, the higher-level code starts by calling a function within the lower-level code, passing to it a pointer or handle to another function. While the lower-level function executes, it may call the passed-in function any number of times to perform some subtask. In another scenario, the lower-level function registers the passed-in function as a handler that is to be called asynchronously by the lower-level at a later time in reaction to something.

A callback can be used as a simpler alternative to polymorphism and generic programming, in that the exact behavior of a function can be dynamically determined by passing different (yet compatible) function pointers or handles to the lower-level function. This can be a very powerful technique for code reuse. In another common scenario, the callback is first registered and later called asynchronously.

Overloading
Function overloading is the use of a single name for several different functions in the same scope. Multiple functions that share the same name must be differentiated by using another set of parameters for every such function. The functions can be different in the number of parameters they expect, or their parameters can differ in type. This way, the compiler can figure out the exact function to call by looking at the arguments the caller supplied. This is called overload resolution, and is quite complex.

Under some circumstances, a call can be ambiguous, because two or more functions match with the supplied arguments equally well.

Example, supposing the declaration of geometric_mean above: // This is an error, because (1) could be called and the second // argument casted to an int, and (2) could be called with the first // argument casted to a double. None of the two functions is // unambiguously a better match. geometric_mean(7, 13.21); // This will call (3) too, despite its last argument being an int, // Because (3) is the only function which can be called with 3 // arguments geometric_mean(1.1, 2.2, 3);

Template and non-template can be overloaded. A non-template function takes precedence over a template, if both forms of the function match the supplied arguments equally well.

Note that you can overload many operators in C++ too.

Overloading resolution
Please beware that overload resolution in C++ is one of the most complicated parts of the language. This is probably unavoidable in any case with automatic template instantiation, user defined implicit conversions, built-in implicit conversation and more as language features. So do not despair if you do not understand this at first go. It is really quite natural, once you have the ideas, but written down it seems extremely complicated.

The easiest way to understand overloading is to imagine that the compiler first finds every function which might possibly be called, using any legal conversions and template instantiations. The compiler then selects the best match, if any, from this set. Specifically, the set is constructed like this:
 * All functions with matching name, including function templates, are put into the set. Return types and visibility are not considered. Templates are added with as closely matching parameters as possible. Member functions are considered functions with the first parameter being a pointer-to-class-type.
 * Conversion functions are added as so-called surrogate functions, with two parameters, the first being the class type and the second the return type.
 * All functions that do not match the number of parameters, even after considering defaulted parameters and ellipses, are removed from the set.
 * For each function, each argument is considered to see if a legal conversion sequence exists to convert the caller's argument to the function's parameters. If no such conversion sequence can be found, the function is removed from the set.

The legal conversions are detailed below, but in short a legal conversion is any number of built-in (like int to float) conversions combined with at most one user defined conversion. The last part is critical to understand if you are writing replacements to built-in types, such as smart pointers. User defined conversions are described above, but to summarize it is
 * 1) implicit conversion operators like <tt>operator short toShort;</tt>
 * 2) One argument constructors (If a constructor has all but one parameter defaulted, it is considered one-argument)

The overloading resolution works by attempting to establish the best matching function.

Looking at one parameter, the preferred conversion is roughly based on scope of the conversion. Specifically, the conversions are preferred in this order, with most-preferred highest:
 * Easy conversions are preferred:
 * 1) No conversion, adding one or more const, adding reference, convert array to pointer to first member
 * 2) const are preferred for rvalues (roughly constants) while non-const are preferred for lvalues (roughly assignables)
 * 3) Conversion from short integral types (bool, char, short) to int, and float to double.
 * 4) Built-in conversions, such as between int and double and pointer type conversion. Pointer conversion are ranked as
 * 5) Base to derived (pointers) or derived to base (for pointers-to-members), with most-derived preferred
 * 6) Conversion to <tt>void*</tt>
 * 7) Conversion to bool
 * 8) User-defined conversions, see above.
 * 9) Match with ellipses. (As an aside, this is rather useful knowledge for template meta programming)

The best match is now determined according to the following rules:

In short, the function must be better in every respect --- if one parameter matches better and another worse, neither function is considered a better match. If no function in the set is a better match than both, the call is ambiguous (i.e., it fails) Example:
 * A function is only a better match if all parameters match at least as well

If all else is equal between two functions, but one is a template and the other not, the non-template is preferred. This seldom causes surprises.
 * Non-template should be preferred over template

When all else is equal between two template function, but one is more specialized than the other, the most specialized version is preferred. Example:
 * Most-specialized template is preferred

Which template is more specialized is an entire chapter unto itself.

This rule is mentioned above, but it bears repeating: Return types are never part of overload resolutions, even if the function selected has a return type that will cause the compilation to fail. Example:
 * Return types are ignored

If the selected best function is not accessible (e.g., it is a private function and the call it not from a member or friend of its class), the call fails.
 * The selected function may not be accessible


text:
Wikijunior:Solar System/Beck Foundation

=Introduction=

=Solar System=

=Mercury=

=Venus=

=Earth=

=Moon=

=Mars=

=Jupiter=

=Saturn=

=Uranus=

=Neptune=

=Pluto=

title: Wikijunior:Solar System/Beck Foundation


text:
Wikijunior:Solar System/Complete

=Introduction=

=Solar System=

=Mercury=

=Venus=

=Earth=

=Earth/Moon=

=Mars=

=Mars/Phobos=

=Mars/Deimos=

=Jupiter=

=Jupiter/Amalthea=

=Jupiter/Io=

=Jupiter/Europa=

=Jupiter/Ganymede=

=Jupiter/Callisto=

=Saturn=

=Saturn/Mimas=

=Saturn/Enceladus=

=Saturn/Tethys=

=Saturn/Dione=

=Saturn/Rhea=

=Saturn/Titan=

=Saturn/Hyperion=

=Saturn/Iapetus=

=Saturn/Phoebe=

=Uranus=

=Uranus/Miranda=

=Uranus/Ariel=

=Uranus/Umbriel=

=Uranus/Titania=

=Uranus/Oberon=

=Neptune=

=Neptune/Proteus=

=Neptune/Triton=

=Neptune/Nereid=

=Pluto=

=Pluto/Charon=

=Comets=

=Kuiper Belt=

=Oort Cloud=

=Glossary=

=About gravity, mass, and weight=

=Space exploration=

title: Wikijunior:Solar System/Complete


text:
Talk:Blender 3D: Noob to Pro/Output Format Options

Missing OS and Blender version --Popski 02:26, 28 August 2005 (UTC)
 * WARNING: I have encountered some crashes when I changed those parameters. If you have problems too, locate the Output sub-context (usually on the left) and select the option DispView instead of DispWin. This renders the image "into" Blender instead of making a new window.

Pre-sets
Maybe adding what parameters are setted after pressing PAL or NTSC button. I can do it. Soeb (talk) 15:18, 20 March 2008 (UTC) Nevermind some one described everything yet. Soeb (talk) 13:02, 10 June 2008 (UTC)


text:
Wikijunior:Solar System/Uranus/Umbriel

Umbriel is a moon of Uranus

How big is Umbriel?
Umbriel is about 1169.4 km wide, or about 1/10th as wide as Earth.

What is its surface like?
The only close-up images we have of Umbriel's surface come from Voyager 2's flyby in January 1986. These images show that Umbriel has a dark surface, the darkest of any of Uranus' moons. Near the equator lies Wunda, a large ring of bright material. Wunda is assumed to be a crater, but nobody is sure what it is exactly. Near Wunda is the crater Skynd.

How long is a day on Umbriel?
One day on Umbriel is equal to about four Earth days.

How long is its orbit around Uranus?
One orbit around Uranus is also equal to about four Earth days.

What is it made of?
Umbriel is made mostly of water ice, followed by silicate rock and methane ice. Most of its methane ice is on its surface.

From guessing based on its mass and size, scientists have worked out that it is about 60% ice and 40% rock.

How would Umbriel's gravity pull on me?
If you stood on Umbriel, you would weigh about one-fortieth (0.023) of what you do on Earth. Someone who weighs 100 lbs on Earth would weigh only about 2.3 lbs on Umbriel.

Who is it named after?
Umbriel is named after the "dusky melancholy sprite" in Alexander Pope's The Rape of the Lock, and the name suggests the Latin umbra, meaning shadow.

How was it discovered?
Umbriel was discovered on October 24, 1851 by William Lassell. He also discovered the moon Ariel at the same time.

Wikijunior Sonnensystem/ Uranus/ Umbriel

title: Wikijunior:Solar System/Uranus/Umbriel


text:
User:Think Fast

Tasks

 * 1) Naming policy—Puzzles
 * 2) Adding content—Spanish, ACT
 * 3) Welcoming new users—Template:Welcome, User:Think Fast/Welcome

Spanish Wikibook

 * 1) Enable users to e-mail their suggestions to major contributors
 * 2) Verb expressions
 * 3) More convos
 * 4) Enable users to write their own conversations which a volunteer would then check
 * 5) Add link to Wikiversity translation practice course
 * 6) Set up pen pal exchange with the es ingles wikilibro
 * 7) Write nouns article
 * 8) Format solutions pages
 * Answers
 * Link to exercise (enlace a los ejercicios)
 * Link to lesson (enlace a la lección)
 * Link to exercises page
 * Link to solutions page

 * 1) Move Index IV
 * 2) Index of all Spanish sound files from Wikicommons
 * 3) More on culture
 * 4) Suggestions from Spanish main page talk page

Request for Adminship
I self-nominated for adminship, but it didn't work out. But you can look at the vote here.

ACT
I have recently started a Wikibook as a study guide for the ACT. There is one for the SAT here, but I could not find one for the ACT. The SAT study guide is here. If anyone would be interested in helping me on the ACT study guide, please sign up on my discussion page for whatever you can do. Thanks.

es:User:Qwerty

title: User:Think Fast


text:
User talk:Think Fast

Picture Issue
I don't know what picture you are referring as untagged. In the book Semiconductor Electronics I have loaded pictures that have been produced by my employees and I pay them. So I own it and have released it under GFDL so that all would benefit. Could you please specify the file names so that I can tag it, in case I have missed it by chance? User : A.K.Karthikeyan

Move tab
To move a badly named page to a correct location, such as from "Spanish/Exercise Telling Time" to "Spanish/Exercises/Telling Time", you can use the "move" tab at the top of each page (next to the history tab), instead of copying the page. This preserves the history of all old versions of this page. (Because "move" also leaves a redirect at the old location, some users nominate the redirect for deletion.) Generally doing a "move" is a better idea than copying a page. The "move" feature is somewhat unique to MediaWiki, and does not seem to exist in most other wiki software, but Wikibookians have used it many times.

You do not need to know all wiki features to use a wiki, so I hope that you continue contributing to Wikibooks. --Kernigh 02:02, 21 June 2006 (UTC)

Column hint and suggestion
You can create columns using wikitables. See Help:Table. This is the basic syntax:

Which makes:

Also consider using {{hidden}} to display solutions instead of separate pages. Good luck on your book, hagindaz 20:11, 24 June 2006 (UTC)

Indonesian wikibook
Hi thinkfast, I'm reorganizing Indonesian to follow French wikibook structure... hope you could help too.. Chaerani 14:20, 30 September 2006 (UTC)

Moving pages
I've just found that you've gone through some of Puzzles moving pages to conform to a "naming convention".

Before you do any more of this, either to Puzzles or to any other wikibook, please: -- Smjg 09:55, 26 November 2006 (UTC)
 * 1) Look on the talk page of the book's main page to check that there isn't already a naming convention being discussed and/or implemented for the book, with which the one you are about to implement may conflict.  If you wish to propose your convention as a better alternative, by all means propose it, and give people time to comment before you implement it.
 * 2) Be sure to think about how the pages are named, rather than blindly copying the existing names (and thereby perpetuating such problems as miscapitalisation or needless repetition of the same word).

Speedy on myers briggs
Just to say I've removed it - it is a perfectly valid redirect to a page with considerable content. If someone was using the old naming strategy they would get there ok - thanks -- Herby talk thyme 08:12, 7 December 2006 (UTC)

You've been thinking too fast
I only just noticed some of the links you changed on Talk:Puzzles about a month ago. In doing so, you altered what I wrote. Those were the days - I proposed a naming scheme whereby the hierarchy levels are delimited by colons. But you changed my proposal to use slashes. Please be a little more careful if you're going to do any more updates of this kind.

Please also read Talk:Puzzles if you haven't already. I agree that using slashes is the way to go now that it has been decreed as the standard. But we still need to come to an agreement on capitalisation before we continue. -- Smjg 18:40, 14 December 2006 (UTC)

Pictures
You write:

 * As you can see at the top of this page, "All unlicensed images uploaded to wikibooks before November 1, 2006 will soon be deleted." You have uploaded images and some of them are untagged. You can see them here.  Please review them and add appropriate tags.  If you have any questions, feel free to ask me.  --Think Fast 04:29, 13 November 2006 (UTC)

Well now. I'll do my best to remain polite, but you're pushing my limit here. I have no idea why you took it upon yourself to destroy things for no good reason. I may have left a tag off an image on occasion, though I doubt it. I'm usually pretty good about marking my images as public domain. Actually, public domain is unlicensed; in fact it can not be licensed because it has no copyright. Most are works of US federal government employees done while performing their jobs; nearly all of the rest are my personal creations.

So, what have you destroyed while I've been away from the wiki? Sorry, real life intrudes at times. I have 5 kids and I've been working 70-hour to 80-hour weeks lately.

BTW, your link is worthless. I get "500 Internal Error" and "The toolserver is ill today.". I also don't "see at the top of this page" anything related to image deletion whatsoever.

Something to think about: I at least made it back to the wiki. Some folks disappear for good. Some folks are actually dead. It's quite unreasonable to expect all contributers to always be able to quickly respond to a demand, especially when that demand is rather pointless. (Was there a cease-and-desist or a DMCA takedown notice, or even a valid reason to suspect that something wasn't right?) I think you'll find that the much-hated DMCA actually protects the wiki from copyright problems caused by badly behaved users.

AlbertCahalan 08:33, 18 December 2006 (UTC)

Spanish wikibook
Check out my new vocabulary page at Spanish/Vocabulary/People. What do you think of structuring the vocabulary pages this way? Cilantrohead (talk) 00:40, 2 March 2008 (UTC)

title: User talk:Think Fast


text: Template:Illegalacts

title: Template:Illegalacts


text:
Talk:Set Theory/Naive Set Theory

hello i am editing talk $$Insert formula here$$

title: Talk:Set Theory/Naive Set Theory


text:
Cookbook:Maple Beans

| North American Cuisines | Cuisine of Ontario

Maple beans is a modification of the standard Baked Beans made throughout much of Europe and North America. This variant is common through south and central Quebec as well as most of Ontario and can be purchased in cans across Canada.

Ingredients

 * 625 ml (2 ½ cups) small dried white beans
 * 2 L (8 cups) water
 * 1 large sweet onion, finely diced
 * 250 ml (1 cup) maple syrup
 * 30 ml (2 Tbsp) dark brown sugar
 * 30 ml (2 Tbsp) butter
 * 2 ml (½ tsp) dry mustard
 * 5 ml (½ tsp) ground pepper
 * 5 ml (1 tsp) salt
 * 6 slices side bacon OR 60 ml (¼ cup) bacon runoff

Procedure

 * 1) Wash beans and place in a saucepan with the water. Cover and bring to a boil, checking regularly.
 * 2) When water has reached the boiling point, time for 5 minutes and remove from heat. Let sit for 1 hour, covered.
 * 3) After the hour, return beans and water to heat and bring to a simmer, still covered. Simmer for 45 minutes.
 * 4) Strain beans and water through a colander, collecting the liquids in a bowl for later use.
 * 5) Combine the onion, salt, mustard, and maple syrup. Add 625 ml (2 ½ cups) of the aforementioned bean-water to the mix and blend well.
 * 6) Finely slice the bacon, place in roast pan/casserole dish, and cover with the beans, pouring the liquid mixture over top.
 * 7) Cover and bake for 3 hours at 165°C (325°F), adding 125 ml (½ cup) of bean-water at the 2 ½ hour mark.
 * 8) Melt butter and combine with brown sugar. Pour over the baked beans and bake, uncovered, until liquid is no longer visible.

Notes, tips, and variations

 * You can substitute honey or molasses for the maple syrup; maple is used for it's flavouring as much as its sweetness.
 * Margarine or vegetable oil will do as well as butter for this; butter was used traditionally and is thus listed.
 * This is often served with ham and sweet cornbread.

title: Cookbook:Maple Beans


text:
User talk:Tmaioli

Hi, i was looking at your bio-tech page and i think its an excellent start, however, there are some minor things which need improvement of. The overall layout tends to get a bit too congested and needs to be layed out a little bit more herichial. Also, chemical formulae such as H202, hydrogen peroxide, need to be written like $$H_2O_2$$...I will come and fix some of these small errors when i have time (im currently in the middle of all my major assesment), keep up the good work --Mitchc 07:08, 28 August 2005 (UTC)

title: User talk:Tmaioli


text:
Talk:A-level Mathematics/OCR/C1

Indices and surds?? Why is the obsolete jargon being used? Surds doesn't even cover all the issues related to matters of roots and powers. I'm all for having a uniform vocabulary across the globe. I couldn't even find any discussion of this choice. In the U.S., which I fully understand is just one country, indices are usually taken to me subscripts used to differentiate elements of an array. I hope that you folks would discuss this and think it through. It was disturbing enough to cause me to create and account. Begs 21:15, 23 June 2006 (UTC)

Syllabus anyone?
Hi, i think we should discuss why were are not sticking to the OCR syllabus like it clearly states on the first page of this book... I mean, differentiation belongs here, and not C2. Clearly stated in the syllabus, page 32... Hmm, I dont understand why we just can't stick to it, and make it less confusing for everyone ! --Mitchc 08:55, 28 August 2005 (UTC) (thoughts and comments welcome)

See my talk page, i discussed it with Mattrix. Basically, I was working from the MEI version of the specification which has a minor difference in its name but big differences to the actual content. Sorry, it was a mistake on my part, all I saw was OCR and Mathematics and mixed the two up. Move everything where you feel they should go. --Krackpipe 13:54, 28 August 2005 (UTC)

Recently, a section link was added for "Principles of mathematical analysis". I'm not sure what this should cover, as unlike most of the other sections list, it doesn't appear to correspond to a heading in the syllabus. Thus, I'm not sure if this should be included here or not. I say most, as Equations, and Error bounds and Inequalities don't. However, equations appears to serve as a basis for the Polynomials section, and the Syllabus does mention inequalities as part of their Polynomials heading. That still leaves the error bounds bit, which doesn't appear to be part of the C1 Syllabus, although it may be part of another module.

Basically, I'm asking Principles of mathematics analysis belongs here, and what content it should include if it doesn, and whether the error bounds content belongs here, or in another module. Silverfish 18:21, 17 December 2005 (UTC)

 * Principles of mathematical analysis seems to have just been randomly made up, it isn't on the syllabus, so I've removed it. Aleksev 00:28, 18 December 2005 (UTC)

Completed?
Is everyone happy that this module is completed to a level?
 * No, A-level_Mathematics/C1/Polynomials needs pictures of the general shapes of curves, two under the paragraph

 * "If the coefficient of x^n is positive, curves with an even value of n will have a bucket shape, and curves with an odd value of n will generally be negative when x is negative, and positive when x is positive (like y = x)."

 * and another two under the paragraph

 * "If the coefficient of x^n is negative, curves with an even value of n will have an upside down bucket shape, and curves with an odd value of n will generally be positive when x is negative, and negative when x is positive (similar to y = − x)."

 * and the page A-level_Mathematics/C1/Coordinate_Geometry_and_Graphs needs images of general curve shapes where i had previously just written "(images here)" or something similar. I think they are essential to demonstrate how the shape of curves change when certain numbers are modified. I would have done them myself but my skills in inkscape/illustrator aren't too great, even after a few tries. I'll take a look at the whole module myself now and check the text itself, but I definately remember leaving out those pictures.--Krackpipe 21:02, 9 January 2006 (UTC)

Differentiation IS NOT C1
Sorry but differentiation has no place here. the differentiation refered to on page 32 of the OCR syllabus is actually how the exam board differentiate between pupils abilities. If you read the C1 specific syllabus starting at page 37 you will find that differentiation is NOT C1

 * 1) Differentiation

ive done C1, and its in there.

C1 definitely does not have differentiation on the OCR syllabus, as it is part of the C2 module -4/11/07

title: Talk:A-level Mathematics/OCR/C1


text:
A-level Biology/Biology Foundation

Biology foundation provides both an introduction to biology and also covers all the basic concepts that will be used throughout most of the other units. This unit is essential to the course structure.

Contents

 * Cell Structure
 * Biological Molecules
 * Enzymes
 * Cell Membranes and Transport
 * Protein Structure and Function
 * Nuclear Division
 * Energy and Ecosystems

title: A-level Biology/Biology Foundation


text:
A-level Biology/Biology Foundation/cell structure

= Cell Structure =

Microscopy
 Different types of microscope

There are two types of microscope - light & electron. Light uses light waves as it's source of radiation and electron microscopes use electrons. This has to do with the wavelength of the radiation - visible light ranges from 400-700 nm, and for the light microscope to see a structure, that structure has to be greater than half the wavelength used, so as to interfere with the light waves and produce an image. This means the maximum resolution of a light microscope is around 200 nm.

Electrons have a much smaller wavelength (at least as small as x-rays) and because they are negatively charged, they can be focused using electromagnets, whereas x-rays cannot). This allows them to see much smaller structures than light microscopes - up to and including 0.5 nm, and a single DNA molecule is 2 nm. Electron microscopes however do have a drawback - the specimen must be scanned in a vacuum, and since water boils at room temperature in a vacuum, all specimens must be dehydrated before being examined, and thus only dead material can be seen.

 Magnification and Resolution

Optical magnification is defined as the ratio between the apparent size of an object (or its size in an image) and its actual size. It can be calculated as thus;

$$magnification = \frac{size-of-image}{actual-size-of-specimen}$$

Resolution on the other hand, is defined as the ability to distinguish between two separate points. If the light microscope cannot distinguish between the two separate points, those two points become one in the resulting image. For example, ribosomes are approximately 25 nm in diameter and when viewed with a light microscope cannot be discerned as it does not interfere with the light waves, whereas a 1000 nm mitochondrion does.

Cell Organelles
An organelle is defined as both a functionally and structurally separate part of the cell and are often surrounded by membranes of their own. This is known as compartmentalisation.

Nucleus

Structure of nucleus

 * Largest organelle
 * Dual-membrane (nuclear envelope) - porous, allowing exchange between nucleus and cell.
 * Sub-structure - nucleolus

Function
 * Controls cells activities
 * mRNA leaves the nucleus to perform protein synthesis
 * Contains chromosomes

Mitochondria

Structure is scientifically very important

 * dual membrane forming an envelope
 * Inner membrane folded to form cristae, projecting to the inside of the mitochondria, known as the matrix

Function

 * Perform later stages of aerobic respiration, a metabolic process that creates ATP
 * Also involved in lipid synthesis

Endoplasmic Reticulum

Structure-.

 * Rough endoplasmic reticulum has its membrane surface lined with ribosomes.
 * Smooth endoplasmic reticulum do not have ribosomes
 * Both form a series of sheets which enclose flattened sacs called a cisternae.

Function:

 * Protein synthesis takes place in ribosomes on the rough endoplasmic reticulum
 * Provide a large surface area for chemical reactions and a pathway for transport of materials through the cell
 * Smooth endoplasmic reticulum is involved in lipid and carbohydrate synthesis and the detoxication of drugs

Golgi Apparatus
Structure

 * Similar to smooth ER, more compact

Function

 * Collect, process and sort molecules.

The stack of flattened sacs (cisternae) are constantly being formed by vesicles budding off at the end of smooth ER and being broken down at the other end to form Golgi vesicles.

Ribosome

Structure

 * One large and one smaller subunit
 * Comprise of RNA (ribosomal) and protein
 * 20 nm size

Function

 * Protein synthesis

Lysosome
Structure

 * Around 0.1-1.0 µm in diameter
 * Membrane surrounding digestive enzymes known as hydrolases

Functions

 * Digesting worn out organelles, or bacterium taken in during phagocytosis
 * Bind to the cell membrane and release their enzymes outside of it in a process known as exocytosis like exocism

Cilia and flagella

These two organelles are almost identical except that cilia are shorter and more numerous. Their structure is a two central micro tubules, surrounded by nine pairs of micro tubules on the outside, wrapped in a plasma membrane, in a long elongated shape similar to a hair. Their function can either be to move an entire organism or to move material within an organism. An example of the latter is the cilia in the trachea moving mucus along the throat.

Centriole
A centriole is a hollow cylinder formed from a ring of microtubules and used to grow the spindle fibres used in nuclear division.

Plasma Membrane
This is a very thin phospholipid bi-layer. It controls the movement of substances in and out of the cell; further explanation can be found later in this book.

Plants Only

Chloroplast

These are relatively large organelles which are only in photosynthesising cells, are green in colour due to the presence of the pigment chlorophyll, and at high magnifications grana can be seen in them. Grana are used in photosynthesis which will be discussed more later.

Vacuole
The vacuole is a fluid filled sac bound by a single membrane - it contains a solution of sugars, amino acids, waste products and mineral salts. It can serve as a temporary store, for waste or food, and can also contain hydrolytic enzymes. They also support some plants by providing an osmotic system which creates a pressure potential.

Cell Wall
Functions of the cell wall in plant cells include preventing the cell bursting when osmosis allows water to enter and provides the cell with structure and a definite shape.

Plasmodesmata
These fine strands of cytoplasm are linked through the cell wall, connecting neighbouring cells.

Refer to the below table for the differences between plant and animal cells.

Prokaryotes and Eukaryotes
Karyote means 'nucleus' and thus prokaryote means 'before nucleus' which is an easy way to remember that these are the less complex cell type. They are also 1,000 to 10,000 times smaller than eukaryotes.

The table below is a comparison of prokaryotic and eukaryotic cells:

=Tissues and Organs=

 * Tissue: A collection of cells specialised to perform one or more functions, and the cells do not have to be of the same type - merely collectively perform the same functions.
 * Organ: Composed of more than one type of tissue which forms a structural and functional unit. Leaves, the brain, the heart are all examples of organs.
 * System: Collection of organs with the same function, such as the digestive system.

Epithelium
Epithelial tissue is tissue that forms sheets covering surfaces and both the types you are required to learn about are said to be simple epithelia as they are one cell thick. They rest on a basement membrane, which is NOT a cell membrane, but rather a network of collagen and glycoproteins and holds the epithelium cells in place.

Squamous Epithelium
Squamous Epithelium is very smooth, flat and thin - they fit together like floor tiles providing a smooth almost frictionless surface over which fluids can move easily. The thickness (or lack thereof) in epithelium aids in processes like diffusion. This type of epithelium cell covers many surfaces in the body, for example the inner surfaces of atria and blood vessels. It also forms alveoli walls.

Ciliated Epithelium
This is epithelium with cilia and is found for example in the trachea, where it is tall and narrow and the cilia is used to waft mucus along the trachea.

Glandular Epithelium
This is epithelium with cells that excrete some substance in the body. Some substances it secretes include hormones, mucous, and lubricating fluid.


text:
User:EnaamA

Regarding help requested
I saw your request for help on Robert Horning's talk page. I've fixed the formatting of the text that you added to Wikijunior Ancient Civilizations/Egyptians. It was simply a matter or removing the spaces at the beginning of the first line of each paragraph.

Citing your sources is always a good idea. But, as this is a Wikijunior book, I would add your references to the talk page Talk:Wikijunior_Ancient_Civilizations/Egyptians instead of the main article (somebody has already stated it there). Geo.T 11:17, 28 August 2005 (UTC)

title: User:EnaamA


text:
User:Sma/german english practise

to be expanded

here, the texts will come in::

31st August
Mars is the English name for the fourth planet from the sun in our solar system. Mars ist der englische Name des vierte Planeten von der Sonne in unserem Sonnensystem.

correction(cor): des vierten Planeten (genetive clause) 'von der Sonne' is ok, but better would be 'von der Sonne aus (gesehen)' meaning 'from the sun's point of view'

Mars is named after the Roman god of war because it is red and red is the colour of blood. Mars ist...............ist rot und rot ist die Farbe des Blut. cor: is named= ist benannt after the Roman god of war= nach dem römischen Gott des Krieges because=weil Farbe des Blutes (again genetive)

Mars has 2 very small moons called Phobus and Deimos. Mars hat zwei sehr kleine Monde....Phobus und Deimos. cor: called= die genannt werden (maybe think of the long English version ', that are called')

The planet Mars is made of rock. Der Planet, Mars, ist aus Stein. cor: why commas? Mars belongs to planet, it's both subject, 'ist aus' is alright, but 'besteht aus'(consists of) sounds better :P

Th e ground there is red because of iron oxide (rust) in the rock and dust. Der Boden ist rot wegen Rost in den Stein und Staub. cor: there=dort wegen Rost is pretty good, you could also use your favorite, the genetive ;), wegen des Rosts    a comma after rot would be better too, but I don't know if it is necessary.     is rock supposed to be plural? if so, it should be 'in den Steinen', if it's singular then it          should be 'im Stein (better: im Gestein)     dust, mhh yes, maybe you should make it to 'dust in the air', so 'im Staub in der Luft', but I       dont get the English right there.

The planet has a very thin carbon dioxide atmosphere. Der Planet hat ein sehr dünnes...... Atmosphäre. cor: Atmosphäre= female (die ~) carbon dioxide= Kohlenstoffdioxid I guess

(Original text at . Dots show inability to translate.)

#3 DATE
to be done like this pattern:

1 English sentence: 1 German sentence :

title: User:Sma/german english practise


text:
Talk:Puzzles/Non-scientific puzzles/Boy, Girl, and a Dog

Answer: Anywhere between 0km and 1km? If the boy is 1km from the girl, the girl facing the boy, the boy facing away, and the dog in between, the girl walks backwards at 4km/h, the boy walks backwards at 5km/h and the dog runs backwards back and forth between the boy and girl with 10km/h, won't they all meet at a point in an hour, no matter where in between the dog starts? (With the dog getting a bit dizzy from turning around an infinite number of times?) كсηפ Cyp 16:01, 28 August 2005 (UTC)


text:
Visual Basic/The Language

Many computer languages share a core set of features. Sometimes they are very similar in different languages, sometimes radically different. Some features regarded by users of one language as indispensable may be completely missing from other perfectly usable languages.

Statements
A statement in Visual Basic is like a command given to the computer. Functions and subroutines are made out of statements.

A statement generally consists of the name of a subroutine followed by a list of arguments:

The first word (Debug) is the name of a built in object in Visual Basic. the second word (Print) is the name of a method of that object. "Hello World" is the argument to the method. The result is:

Hello World

printed to the Immediate Window.

In Visual Basic Classic subroutine call statements can be written in two ways:

x is a subroutine which takes two string arguments. The keyword Call is a leftover from older versions of Basic. If you use this form you must enclose the entire argument list in a parenthesis. Sometimes the programmer wants to call a function but is not interested in the return value only in the side-effects. In such cases he or she will call the function as though it were a subroutine, however only the first form above can be used.

There are other more complex statements which can span several lines of code:

 * If..Else..End If
 * Do While..Loop

These compound statements include other statements and expressions.

Variables
Like most programming languages, Visual Basic is able to use and process named variables and their contents. Variables are most simply described as names by which we refer to some location in memory - a location that holds a value with which we are working.

It often helps to think of variables as a 'pigeonhole', or a placeholder for a value. You can think of a variable as being equivalent to its value. So, if you have a variable i that is initialized to 4, i+1 will equal 5.

In Visual Basic variables can be declared before using them or the programmer can let the compiler allocate space for them. For any but the simplest programs it is better to declare all variables. This has several benefits:

 * you get the datatype you want instead of Variant,
 * the compiler can sometimes check that you have used the correct type.

All variables in Visual Basic are typed, even those declared as Variant. If you don't specify the type then the compiler will use Variant. A Variant variable is one that can hold data of any type.

Declaration of Variables
Here is an example of declaring an integer, which we've called.

Dim some_number As Integer

You can also declare multiple variables with one statement:

This is not a good idea because it is too easy to forget that in Visual Basic the type name applies only to the immediately preceding variable name. The example declares two Variants and one Integer

You can demonstrate what actually happens by this little program:

The result is:

Empty         0            Empty          0            Integer        2 Empty         0 Assign a number to anumber Integer       2 Assign a string to anumber String        8

Notice that both VarType and TypeName return information about the variable stored inside the Variant not the Variant itself.

To declare three integers in succession then, use:

In Visual Basic it is not possible to combine declaration and initialization with variables (as VB does not support constructors - see Objects and Initialise though), the following statement is illegal:

Only constant declarations allow you to do this:

In Visual Basic variables may be declared anywhere inside a subroutine, function or property, where their scope is restricted to that routine. They may also be declared in the declarations section of a module before any subroutines, functions or properties, where they have module level scope.

By default, variables do not have to be declared before use. Any variables created this way, will be of Variant type. This behaviour can be overrriden by using the Option Explicit statement at the top of a module and will force the programmer to declare all variables before use.

After declaring variables, you can assign a value to a variable later on using a statement like this:

The use of the Let keyword is optional, so:

is also a valid statement.

You can also assign a variable the value of another variable, like so:

In Visual Basic you cannot assign multiple variables the same value with one statement. the following statement does not do what a C programmer would expect:

Instead it treats all but the first = signs as equality test operators and then assigns either True or False to anumber depending on the values of anothernumber and yetanotherniumber.

Naming Variables
Variable names in Visual Basic are made up of letters (upper and lower case) and digits. The underscore character, "_", is also permitted. Names must not begin with a digit. Names can be as long as you like.

Some examples of valid (but not very descriptive) Visual Basic variable names:

foo Bar BAZ foo_bar a_foo42_ QuUx

Some examples of invalid Visual Basic variable names:
 * 2foo:must not begin with a digit
 * my foo:spaces not allowed in names
 * $foo:$ not allowed -- only letters, digits, and _
 * while:language keywords cannot be used as names
 * _xxx:leading underscore not allowed.

Certain words are reserved as keywords in the language, and these cannot be used as variable names, or indeed as names of anything else.

In addition there are certain sets of names that, while not language keywords, are reserved for one reason or another.

The naming rules for variables also apply to other language constructs such as function names and module names.

It is good practice to get into the habit of using descriptive variable names. If you look at a section of code many months after you created it and see the variables,   etc., you will more than likely have no idea what they control. Variable names such as  or   are much more descriptive - you know exactly what they do. If you have a variable name comprised of more than one word, it is convention to begin the next word with a capital letter. Remember you can't use spaces in variable names, and sensible capital use makes it easier to distinguish between the words. When typing the variable name later in the code, you can type all in lowercase - once you leave the line in question, if the variable name is valid VB will capitalize it as appropriate.

Literals
Anytime within a program in which you specify a value explicitly instead of referring to a variable or some other form of data, that value is referred to as a literal. In the initialization example above, 3 is a literal. Numbers can be written as whole numbers, decimal fractions, 'scientific' notation or hex. To identify a hex number, simply prefix the number with &H.

Conditions
Conditional clauses are blocks of code that will only execute if a particular expression (the condition) is true.

If Statements
If statements are the most flexible conditional statements: see Branching

Select Case
Often it is necessary to compare one specific variable against several values. For this kind of conditional expression the Select Case statement is used.

Unconditionals
Unconditionals let you change the flow of your program without a condition. These are the Exit, End and Goto statements.

Loops
Loops allow you to have a set of statements repeated over and over again.

To repeat a given piece of code a set number of times or for every element in a list: see For..Next Loops

title: Visual Basic/The Language


text:
Radiation Oncology/Colon/NSABP trials

The National Surgical Adjuvant Breast and Bowel Project (NSABP):

See other NSABP trials and NSABP Rectal trials See the NSABP web page.

 * C-01 - Dukes B and C, randomized after curative resection to no further treatment, vs. 5-FU + semustine + vincristine (MOF), vs. BCG (1977-83)
 * PMID 3276901 (1988), 10 year results: PMID 15292384 (2004)

 * C-03 (1987-89) - Resected Stage II-III colon ca, 5-FU/LV vs MOF(semustine, vincristine, and 5-FU)
 * PMID 8410113 (1993)
 * 10-year results (2005): O'Connell MJ et al. J Clin Oncol (Meeting Abstracts) 2005 23: 3511.

 * C-04 (1989-90) - Stage II-III. 5-FU/levamisole(LEV) vs 5-FU/LV vs 5-FU/LV/LEV.
 * PMID 10550154 (1999)

 * C-06 (1997-99) - Resected Stage II-III colon ca, 5-FU/LV vs oral uracil/tegafur (UFT). Equivalence trial.
 * PMID 16648506 (2006)
 * PMID 17264338 (2007) - quality of life

title: Radiation Oncology/Colon/NSABP trials


text:
Radiation Oncology/Colon

 * See also: Colon randomized evidence
 * See also: NSABP Colon trials
 * See also: Rectum Official Guidelines (for now, contains colorectal guidelines)

Anatomy
Relations to peritoneum:
 * cecum: intraperitoneal
 * ascending colon: retroperitoneal
 * posterior surface lacks serosa, is in direct contact with the retroperitoneum. anterior and lateral surfaces have serosa.
 * transverse colon: intraperitoneal
 * descending colon: retroperitoneal
 * posterior surface lacks serosa, is in direct contact with the retroperitoneum. anterior and lateral surfaces have serosa.
 * sigmoid colon: intraperitoneal
 * rectum:
 * upper third: covered by peritoneum on the anterior wall and both sides
 * middle third: covered by peritoneum only on the anterior wall
 * lower third: infraperitoneal

Epidemiology

 * #2 cause of cancer deaths in US after lung cancer with 185,000 new cases and 55,000 deaths/year. Affects males/females equally. Lifetime risk is 5%.
 * 5% due to mutations in mismatch repair genes; 1% due to FAP gene.
 * Patients with familial risk (two or more first or second degree relatives) make up about 20% of patients; those with autosomal dominant mutations make up 5-10%.
 * Average age (for sporadic cases) is 63
 * Increased risk with moderate/heavy alcohol use, animal fat, and red meat.
 * Folate intake associated with a decreased risk.

Survival

 * Stage I: 85-100%
 * Stage IIA: 70%
 * Stage IIB: 30%
 * Stage IIIA-B: 60%
 * Stage IIIC: 30%
 * Stage IV: 3%

Treatment Overview
Treatment is surgical. >12 lymph nodes required for adequate surgical staging.

Primary Surgery
Surgical technique:
 * RTOG 94-15 / INT 0146 / NCCTG 93-46-53 (closed 2001) - Laparoscopic colectomy vs open colectomy.

''Patterns of failure:
 * MGH
 * 1985 (1970-1977) PMID 3973649 -- "Obstructive and perforative colonic carcinoma: patterns of failure." (Willett C, J Clin Oncol. 1985 Mar;3(3):379-84.)
 * Retrospective. 77 patients with obstruction and 34 with perforation; compared with control 400 patients. Minimum F/U 5 years
 * 5-year OS: obstruction/perforation 31% vs. 59%; DFS 44% vs. 75%
 * Obstruction: 42% local failure (28% local only, 72% local and distant)
 * Perforation: 44% local failure
 * Control group: 14% local failure
 * 1984 PMID 6735753 -- "Local failure following curative resection of colonic adenocarcinoma." (Willett C, Int J Radiat Oncol Biol Phys. 1984 May;10(5):645-51.)
 * Retrospective. 533 patients.
 * LR: overall 19%, 30% local only / 70% concurrent local and distant failure
 * LR: 82% in tumor bed and adjacent soft tissues, 18% in LNs
 * By stage: B3/C2-C3 LR >30%, A/B1-B2/C1 <4%
 * By LN: LN1 27%, LN5+ 50%

 * 1981 PMID 7209752 -- "Analysis of recurrence patterns following curative resection for carcinoma of the colon and rectum." (Malcolm AW, Surg Gynecol Obstet. 1981 Feb;152(2):131-6.)
 * Retrospective. 285 patients.
 * Recurrence by location: overall 27%; right 24%, transverse 10%, left 11%, sigmoid/rectum 35%
 * Recurrence by stage: A 13%, B1 11%, C1 32%, B2-3 37%, C2-3 56%
 * Recurrence by location/stage: right (0%, 9%, 33%, 28%, 43%), transverse/left (too few), sigmoid (11%, 15%, 40%, 52%, 62%), rectum (29%, 14%, 40%, 46%, 60%)

Post-operative radiotherapy
Randomized
 * Intergroup 0130 (1992-96) - chemo vs chemo + RT
 * 187 pts. Randomized Phase III. Resected pts with: 1) T4 (any site), or 2) T3N+ (of ascending or descending colon only). Trial closed due to poor accrual (goal of 700 pts).
 * PMID 15249584, 2004 — "Phase III study of adjuvant chemotherapy and radiation therapy compared with chemotherapy alone in the surgical adjuvant treatment of colon cancer: results of intergroup protocol 0130." Martenson JA Jr et al. J Clin Oncol. 2004 Aug 15;22(16):3277-83.
 * 5-yr OS 62% (chemo) vs 58% (chemo/RT), NS. No difference in 5-yr DFS 51% vs 51%.
 * Comments : Lots of issues - End point survival without looking at local control, RT fields included para-aortic LNs, not sufficient power (accrued 25% patients), high number of ineligible patients (15%), broad eligibility criteria (including low risk T3N1), chemotherapy now outdated, inability in many patients to determine tumor location (no preop imaging, no surgical clips), radial margins often not examined on pathology

Retrospective
 * MGH
 * 1999 PMID 10439171 -- "Does postoperative irradiation play a role in the adjuvant therapy of stage T4 colon cancer?" (Willett CG, Cancer J Sci Am. 1999 Jul-Aug;5(4):242-7.)
 * Retrospective. 152 patients with T4, treated with post-op RT +/- 5FU. 110 had R0, 42 had residual tumor
 * T4N1: 10-year LC 88%, DFS 58%; if more than 1 LN worse outcome
 * T4 and perforation/fistula: LC 81%, DFS 53%
 * R+: DFS 19%
 * Conclusion: compared to historical controls, RT should be considered for 1) invasion of adjoining structures, 2) associated perforation or fistula, or 3) residual disease
 * 1993 (1976-1989) PMID 8501497 -- "Postoperative radiation therapy for high-risk colon carcinoma." (Willett CG, J Clin Oncol. 1993 Jun;11(6):1112-7.)
 * Retrospective. 203 post-op RT +/- 5-FU after resection of B2-3 or C2-3 colon. 15% residual disease. Compared to 395 historical control undergoing surgery only
 * Improvement after RT in: 1) B3 and C3, 2) associated abscess or fistula, 3) residual local disease after subtotal resection

 * Mayo, 1997 (1974-1994) PMID 9054876 -- "The treatment of locally advanced colon cancer." (Schild SE, Int J Radiat Oncol Biol Phys. 1997 Jan 1;37(1):51-8.)
 * Retrospective. 103 patients with locally advanced colon CA, 40 R0, 18 R1, 35 R2. Median F/U 5.8 years
 * EBRT given 1-4 after resection to tumor bed + LNs 16-60 Gy; IORT to 11 patients. Chemo 77 patients
 * 5-year LR: 10% R0, 54% R1, 79% R2 (SS); 5-year OS: 66% R0, 47% R1, 23% R2 (SS)
 * IORT: LR IORT 11% vs. EBRT only 82% (SS); 5-year OS: IORT 76% vs. EBRT only 26%
 * Conclusion: In locally advanced colon, high probability of local control with EBRT +/- 5-FU. IORT improves control with residual disease

 * West Florida, 1996 PMID 8876884 -- "Postoperative radiotherapy for locally advanced colon cancer." (Amos EH, Ann Surg Oncol. 1996 Sep;3(5):431-6.)
 * Retrospective. 78 patients with complete resection of B2-C colon CA. 28 patients RT <=45 Gy, 50 patients RT 50-55 Gy. 27 patients 5-FU. Minimum F/U 3 years
 * LR: 12%; RT <45 Gy 24% vs. RT 50-55 4% (SS)
 * Side effects: bowel obstruction 3 patients, sarcoma 1 patient
 * Conclusion: PORT improves risk of LR in locally advanced colon CA
 * Editorial: PMID 8876882 -- "Postoperative radiotherapy for locally advanced colon cancer." (Janjan NA, Ann Surg Oncol. 1996 Sep;3(5):421-2.)

IORT
 * Mayo, 1997 (1981-1995) PMID 9112459 -- "Locally advanced primary colorectal cancer: intraoperative electron and external beam irradiation +/- 5-FU." (Gunderson LL, Int J Radiat Oncol Biol Phys. 1997 Feb 1;37(3):601-14.)
 * Retrospective. 61 patients treated with surgery, IORT 10-20 Gy, usually with EBRT 45-55 Gy +/- 5-FU. Residual disease at IORT unresected 1, gross 16, microscopic/negative 39
 * Failure: in-field 25% in gross vs. 5% in microscopic/negative
 * Conclusion: OS and disease control improved with IORT

Adjuvant liver chemo-RT
 * GITSG, 1991 PMID 1938512 -- "Adjuvant therapy with hepatic irradiation plus fluorouracil in colon carcinoma. The Gastrointestinal Tumor Study Group." (No Authors, Int J Radiat Oncol Biol Phys. 1991 Oct;21(5):1151-6.)
 * Randomized. 300 patients. Curative resection of transmural or N+ colon cancer, treated with 1) observation or 2) 5-FU + 21Gy to liver
 * No benefit; liver recurrence rate same

Regimens
(Note: This section is intended to highlight some of the common chemotherapy regimens used today, but an in-depth discussion of chemotherapy should be reserved for a Medical Oncology textbook)

Chemotherapy is recommended for all Stage III (i.e. node-positive) patients. Some stage II (T3-4 N0) patients may also benefit, but the treatment is made on a case-by-case basis.

 * Mayo Regimen (5-FU/LV)
 * 5-FU, 425 mg/m2/d IV days 1-5. LV 20 mg/m2/d IV days 1-5. Repeat q28d x 6 cycles.
 * Roswell Park (5-FU/LV)
 * 5-FU, 500 mg/m2/d IV weekly x 6. LV 500 mg/m2/d IV weekly x 6. Repeat q8w x 4 cycles.
 * FOLFOX 4 (5-FU/LV/Oxaliplatin)
 * Oxaliplatin, 85 mg/m2 IV day 1. LV, 200 mg/m2/day IV days 1-2. 5-FU, 400 mg/m2/day IV days 1-2. 5-FU, 600 mg/m2/day CI over 22 h, days 1-2. Repeat q14d x 12 cycles.
 * IFL (bolus 5-FU/LV/Irinotecan) - not used, excess mortality from increased toxicity
 * FOLFIRI (infusional 5-FU/LV/Irinotecan)
 * Xeloda (capecitabine)
 * 1250 mg/m2 BID x 14 days. Repeat q21d x 8 cycles.

Trials
See: NSABP Colon trials

 * CALGB 89803
 * Randomized. 1264 patients with completely resected Stage III colon CA. Treated with weekly bolus 5-FU/Leukovorin +/- irinotecan
 * 2007 PMID 17687149 -- "Irinotecan fluorouracil plus leucovorin is not superior to fluorouracil plus leucovorin alone as adjuvant treatment for stage III colon cancer: results of CALGB 89803." (Saltz LB, J Clin Oncol. 2007 Aug 10;25(23):3456-61.)
 * Outcome: No difference in DFS or OS
 * Toxicity: Significantly higher in 5-FU/LV/Irinotecan arm
 * Conclusion: Addition of irinotecan not beneficial in completely resected Stage III

 * NSABP C-01 (1977-83)
 * 1166 pts. Dukes B and C. Randomized after curative resection to 1) chemotherapy with 5-FU, semustine, and vincristine, 2) BCG, or 3) no further treatment.
 * First report: PMID 3276901 (1988)
 * Showed increase in DFS and survival for chemotherapy. Increased survival but not DFS for BCG (due to decrease in non-cancer related deaths)
 * 10-year results: PMID 15292384 (2004)
 * No difference in DFS or survival for chemotherapy group. Decrease in non-cancer related deaths for BCG.
 * Conclusion: DFS benefit for chemotherapy disappears by 10 years.

Pelvic Recurrence

 * Mayo, 2001 (1981-1994) PMID 11286833 -- "Intraoperative irradiation for locally recurrent colorectal cancer in previously irradiated patients." (Haddock MG, Int J Radiat Oncol Biol Phys. 2001 Apr 1;49(5):1267-74.)
 * Retrospective. 51 patients. Salvage surgery + IORT after prior EBRT. IORT 20 Gy (10-30) + in 37 patients EBRT median 25 Gy + 20 patients 5-FU
 * Median OS: 23 months; 2-year OS 48%
 * 2-year LR: 40%; trend to improvement if IORT + EBRT >30 Gy (LR 19%). 2-year DM: 56%
 * Side effects: peripheral neuropathy related to IORT (32% patients); ureteral narrowing/obstruction
 * Conclusion: local control can be obtained, but survival poor due to distant mets

 * MD Anderson, 1996 PMID 8597512 -- "Preoperative infusional chemoradiation, selective intraoperative radiation, and resection for locally advanced pelvic recurrence of colorectal adenocarcinoma." (Lowy AM, Ann Surg. 1996 Feb;223(2):177-85.)
 * Prospective. 43 patients with locally advanced pelvic recurrence of CRC. Treated with RT 45 Gy + C.I. 5-FU and/or cisplatin, followed by surgery + IORT 10-20 Gy or BT. Median F/U 26 months
 * 40 patients underwent surgery, 77% with curative intent. 88% SM-, 48% sphincter-preserving
 * Side effects: 51%
 * LR rate: 36%, 5-year OS: 58%
 * Conclusion: Preop CRT can increase resectability and enable sphincter preservation

Chemotherapy for metastatic disease
Randomized trials for first-line therapy
 * BICC-C -- Irinotecan-based regimens
 * Randomized. 430 patients. Arm 1) FOLFIRI (infusional 5-FU, leucovorin, irinotecan) vs. Arm 2) mIFL (bolus 5-FU, leucovorin, irinotecan) vs. Arm 3) CapeIRI (capecitabine, irinotecan). Concurrently +/- celecoxib. After amendment, dropped Arm 3. Then additional 117 patients randomized to bevacizumab: FOLFIRI-Bev or mILF-Bev. Primary endpoint PFS
 * 2007 PMID 17947725 -- "Randomized, controlled trial of irinotecan plus infusional, bolus, or oral fluoropyrimidines in first-line treatment of metastatic colorectal cancer: results from the BICC-C Study." (Fuchs CS, J Clin Oncol. 2007 Oct 20;25(30):4779-86.)
 * Outcome: PFS FOLFIRI 7.6 month vs. mIFL 5.9 months (SS) vs. CapeIRI (SS).
 * Secondary: FOLFIRI-Bev no median reached yet vs. mIFL-Bev 19.2 (SS)
 * Conclusion: FOLFIRI and FOLFIRI-Bev better than their comparators

 * SGO -- XELOX vs. FUOX
 * Randomized. 348 patients. Arm 1) XELOX (oral capecitabine 1,000 mg/m2 bid for 14 days plus oxaliplatin 130 mg/m2 on day 1 every 3 weeks) vs. Arm 2) FUOX (continuous-infusion FU 2,250 mg/m2 during 48 hours on days 1, 8, 15, 22, 29, and 36 plus oxaliplatin 85 mg/m2 on days 1, 15, and 29 every 6 weeks)
 * 2007 PMID 17548839 -- "Phase III study of capecitabine plus oxaliplatin compared with continuous-infusion fluorouracil plus oxaliplatin as first-line therapy in metastatic colorectal cancer: final report of the Spanish Cooperative Group for the Treatment of Digestive Tumors Trial. (Diaz-Rubio E, J Clin Oncol. 2007 Sep 20;25(27):4224-30.)
 * Outcome: median TTP 9 months (NS), median OS 18 vs. 21 months (NS)
 * Toxicity: comparable
 * Conclusion: XELOX is an alternative to FUOX

 * AIO -- CAPOX vs. FUFOX
 * Randomized. 474 patients, first line therapy. Arm 1) CAPOX (capecitabine 1,000 mg/m2 bid, days 1 to 14 plus oxaliplatin 70 mg/m2 days 1 and 8, repeated every 22 days) vs. Arm 2) FUFOX (oxaliplatin 50 mg/m2 followed by leucovorin 500 mg/m2 plus FU 2,000 mg/m2 as a 22-hour infusion days 1, 8, 15, and 22, repeated every 36 days). Primary end point: PFS
 * 2007 PMID 17548840 -- "Phase III study of capecitabine plus oxaliplatin compared with fluorouracil and leucovorin plus oxaliplatin in metastatic colorectal cancer: a final report of the AIO Colorectal Study Group." (Porschen R, J Clin Oncol. 2007 Sep 20;25(27):4217-23.) ***Outcome: median PFS CAPOX 7 months vs. FUFOX 8 months (NS); median OS 17 months vs. 19 months (NS)
 * Toxicity: CAPOX higher Grade 2-3 hand-foot syndrome
 * Conclusion: CAPOX slightly worse efficacy and toxicity than FUFOX

 * GONO Trial -- '''FOLFOXIRI vs. FOLFIRI"
 * Randomized. 244 patients, unresectable metastatic CRC, no prior chemo for advanced disease. Treated with 1) FOLFOXIRI (irinotecan 165 mg/m2 day 1, oxaliplatin 85 mg/m2 day 1, leucovorin 200 mg/m2 day 1, fluorouracil 3,200 mg/m2 48-hour continuous infusion starting on day 1, every 2 weeks) vs. FOLFIRI (infusional fluorouracil, leucovorin, and irinotecan). Primary end-point response rate (RR)
 * 2007 PMID 17470860 -- "Phase III trial of infusional fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) compared with infusional fluorouracil, leucovorin, and irinotecan (FOLFIRI) as first-line treatment for metastatic colorectal cancer: the Gruppo Oncologico Nord Ovest." (Falcone A, J Clin Oncol. 2007 May 1;25(13):1670-6.)
 * Toxicity: Grade 2-3 neurotoxicity 19% vs. 0% (SS), Grade 3-4 neutropenia (50% vs. 28%, SS)
 * Response rate: 66% vs. 41% (SS); better R0 secondary resection rate of mets
 * Outcome: median PFS 9.8 months vs. 6.9 months (SS); median OS 22.6 months vs. 16.7 months (SS)
 * Conclusion: FOLFOXIRI improves RR, PFS, and OS with manageable toxicity

Familial syndromes

 * Familial adenomatous polyposis (FAP)
 * Adenomatous polyposis coli (APC) gene (5q21) - gatekeeper (controls other downstream genes).
 * 100% progress to carcinoma, most by age 30, often in teens. 100s-1000s of polyps. Other malignancies: thyroid, GB, adrenal. image
 * Cowden's syndrome
 * Autosomal dominant with facial tricholemmomas, acral keratoses, oral mucosal papillomas, colorectal polyps. Patients have increased risk of malignancy (breast and thyroid cancer), but not in polyps.
 * Gardner syndrome
 * Colonic adenomatous polyps plus multiple osteomas (skull, mandible, long bones), epidermal cysts, fibromatosis (usually intraabdominal after surgery), fibromas, lipomas, impacted and supernumerary teeth, dental cysts, lymphoid polyps in small intestine and fundic gland polyps in stomach. 100% develop colon cancer. Other malignancies: periampullary, thyroid, adrenal.
 * Mutation in APC gene but has variable penetrance so not all extracolonic features are present.
 * Lynch syndrome (HNPCC)
 * Most common hereditary colon syndrome (but less than 5% of carcinomas). Dominant. Type 1 - 50% risk of colon ca in relatives. Type 2 - also with endometrial ca, cholangiocarcinoma. Favorable clinical course (increased survival, respond better to chemo).
 * Criteria: 3 colon cancers in which 2 people are first-degree relatives of the third. Cancer in 2 generations. One diagnosis before age 50. No evidence of FAP.
 * Average age of developing cancer: 45 years (vs 63)
 * Screening: full colonoscopy q3y beginning age 20-25; annual endometrial screening age 25-35;

title: Radiation Oncology/Colon