Topology

Topology - Part 1

Order: Reorder
Duration: 14:58
Updated: 16 Aug 2013

Part 1 of the Topology series from Why U. A humorous look at the topology of curved space. For more information visit www.WhyU.org.

http://wn.com/Topology_Part_1

AlgTop0: Introduction to Algebraic Topology

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Duration: 30:05
Updated: 10 Aug 2013

This is the Introductory lecture to a beginner's course in Algebraic Topology given by N J Wildberger of the School of Mathematics and Statistics at UNSW in ...

http://wn.com/AlgTop0_Introduction_to_Algebraic_Topology

MathHistory17: Topology

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Duration: 55:48
Updated: 17 Aug 2013

This video is the last in this series on the History of Mathematics, and gives a brief introduction to Topology. The subject goes back to Euler (as do so man...

http://wn.com/MathHistory17_Topology

Hitler Learns Topology

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Duration: 3:50
Updated: 16 Aug 2013

Hitler gets confused about the topological definitions of open and closed sets. Then he totally freaks out.

http://wn.com/Hitler_Learns_Topology

Introduction to Higher Mathematics - Lecture 14: Topology

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Duration: 36:28
Updated: 18 Aug 2013

Here we delve a bit into the realm of topology, adding a notion of "closeness" to our sets and seeing how that helps us understand the real numbers.

http://wn.com/Introduction_to_Higher_Mathematics_Lecture_14_Topology

Bob Franzosa - Introduction to Topology

Order: Reorder
Duration: 54:04
Updated: 09 Aug 2013

http://www.coa.edu 2010.02.09 Introduction to Topology: From the Konigsberg Bridges to Geographic Information Systems. Topology is the study of the spatial p...

http://wn.com/Bob_Franzosa_Introduction_to_Topology

General Topology Lecture 1 Part 1

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Duration: 13:40
Updated: 01 Aug 2013

Lecture written by Victor Victorov and edited and presented by James Dilts Definition and Examples.

http://wn.com/General_Topology_Lecture_1_Part_1

Topology Without Tears - Video 4a - Writing Proofs in Mathematics

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Duration: 14:58
Updated: 09 Aug 2013

This is part (a) of the fourth video in a series of videos which supplement my online book,"Topology Without Tears", which is available free of charge at www...

http://wn.com/Topology_Without_Tears_Video_4a_Writing_Proofs_in_Mathematics

General Topology Lecture 01 Part 1

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Duration: 19:50
Updated: 12 Aug 2013

First lecture in general topology. Topics include a brief history of topology, basic facts from set theory, an introduction to relations and functions, and a...

http://wn.com/General_Topology_Lecture_01_Part_1

Topology: Jordan's Curve Theorem

Order: Reorder
Duration: 1:58
Updated: 16 Aug 2013

Excerpt from the IBM film "Mathematics Peepshow".

http://wn.com/Topology_Jordan's_Curve_Theorem

Topology #1 Metrics

Order: Reorder
Duration: 8:07
Updated: 13 Aug 2013

Introduction to Metrics.

http://wn.com/Topology_1_Metrics

Topology - Part 2

Order: Reorder
Duration: 8:18
Updated: 24 Jun 2013

Part 2 of the Topology series from Why U. A humorous look at the topology of curved space. For more information visit www.WhyU.org.

http://wn.com/Topology_Part_2

Introduction to Topology

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Duration: 8:30
Updated: 28 Jul 2013

This first lecture of the series Comically Small Lectures On Point Set Topology. We will give: the definition of a topology, open and closed sets, and the ba...

http://wn.com/Introduction_to_Topology

Sawagi -Topology- MV

Order: Reorder
Duration: 5:02
Updated: 12 Jun 2013

名盤「PUNCH GAMES」からTopologyのMVが完成！

http://wn.com/Sawagi_-Topology_MV

Visualize Network Topology with SolarWinds Network Topology Mapper

Order: Reorder
Duration: 3:16
Updated: 08 Aug 2013

For more information on NTM, visit: http://bit.ly/Visualize_with_NTM Learn about SolarWinds new network mapping software, Network Topology Mapper (NTM). NTM ...

http://wn.com/Visualize_Network_Topology_with_SolarWinds_Network_Topology_Mapper

Topology Brush - Chapter 01

Order: Reorder
Duration: 9:20
Updated: 14 Aug 2013

In Chapter 1, we start with creating a single Polygroup for our prop before moving into the basic principles of the Topology Brush. We look at how curve line...

http://wn.com/Topology_Brush_Chapter_01

DNA TOPOLOGY.avi

Order: Reorder
Duration: 8:35
Updated: 13 Aug 2013

it describes about the twist and writhe indna and about the linking number.

http://wn.com/DNA_TOPOLOGYavi

DNA topology with string

Order: Reorder
Duration: 20:20
Updated: 25 Sep 2013

==Origin of the major and minor grooves== Hold strings parallel, look at grooves on both sides. Twist strings, the grooves are still there and still separate, just harder to follow. ==Linking number (Lk)== Hold your strings parallel with both hands and then with your right hand rotate the top of the string towards you, you are increasing the linking number. Rotate it away from you, you are decreasing the linking number. If you twist in the middle without letting the ends rotate, the linking number in the regions on either side of where you twist go in opposite directions, but the total linking number remains the same. ==Linking number in relaxed double stranded DNA== If you hang two pieces of string next to each other they don't wrap around each other. If you hang two complementary strands of DNA next to each other (under normal cellular conditions), they form a right handed helix with 10.5 bp per turn. From that point, if you twist the strands you are creating tension. Twist in a right handed manner and you are "overwinding" Twist in a left handed manner and you are "underwinding" ==Supercoiling== Twist your string together move ends closer together. The easiest thing for string to do is just unwind at the end. DNA can't do that because of friction with water against the extremely long tail keeps that from happening in Eukaryotes. It doesn't happen in prokaryotes because the chromosome is circular. For string, you're holding the ends, so it can't return to its relaxed state. Instead, it twists around itself (in the opposite directions to how you wound it). A positive super coil is left handed because it is caused by over-twisting in the right hand direction. A negative super coil is right handed because it is caused by over twisting in the left hand direction. If you just let one end hang, the free end twists to relieve tension. If the slack is in the middle rather than at the end it will twist in exactly the same way, but when it rotates in the middle it wraps around itself rather than rotating freely. ==Supercoiled DNA is compact== More supercoiling = more compact. Same for prokaryotes (circle) and eukaryotes (linear). Most cellular DNA has negative supercoiling. Decreasing Lk makes it more supercoiled (Lk gets further away from the relaxed state). Increasing Lk makes it less supercoiled (Lk gets closer to the relaxed state). Sometimes when you run a gel with DNA isolated from cells (for example plasmids from bacteria) you see multiple bands when you expect to see only one. This is due to supercoiling. Remember, gels don't always separate DNA by strand length. Only (short) linear DNA. ==Twist and Writhe== When you twist the free ends of string you are changing linking number by changing twist. When the coils of string wrap around each other positive (or negative) twist is being converted into writhe of the same sign (positive to positive, negative to negative) so that linking number is preserved. When you let the strings supercoil, the individual strands become less tightly wound around each other. Twist is being converted into writhe. Until you let the end rotate, Lk remains the same. When you let the end unwind, you are decreasing linking number. ==Type I Topoisomerase== It's not too difficult to see how this would work with string. If you cut one strand in the middle, you can increase Lk by wrapping it around the other strand in a right handed direction, and decrease Lk by wrapping it in a left handed direction. ==Type II Topoisomerase== We can't really simulate double strand breaks with string too easily. But we still see how this works. Make a loop in the string, then pass one end of the string under the other one. Make another loop (with the same handedness) and repeat. By making a loop with the other handedness you can change linking number in the opposite direction. When the strand that starts on top is pointing to the right, pulling it through will decrease linking number, when the strand that starts on top is pointing to the left, pulling it through will increase linking number. Try it with supercoils as well and notice how based on the natural writhe of the supercoil a type II topo would relieve it. ==Nucleosomes== Take two strings of different colors (easier to follow). Wrap the strings around a finger or a pen such that the colors alternate along the pen. Wrap without letting go of either end of the string. (Wrap in a 'left handed' manner, that is, make a left handed spiral on the pen). Notice that tension builds up on the non-wrapped parts of the string. Pull it off, Lk is the same (still zero) Wrap again, this time let the tension at the end be relieved. Then take it off. ==Helicase== stick finger through string, push in one direction. The string winds tighter in front, and less tight behind. Most Images from Lehninger Principles of Biochemistry 5th edition. Helicase from Wikipedia.

http://wn.com/DNA_topology_with_string

Network topology and concepts

Order: Reorder
Duration: 8:10
Updated: 15 Aug 2013

http://wn.com/Network_topology_and_concepts

General Topology Introduction Part 1

Order: Reorder
Duration: 13:05
Updated: 03 Aug 2013

Lecture written by Victor Victorov and edited and presented by James Dilts Topology of the Real Line.

http://wn.com/General_Topology_Introduction_Part_1

Basic Topology in ArcMap

Order: Reorder
Duration: 6:03
Updated: 18 Jul 2013

Brief demo of creating topology in a file geodatabase using ArcMap 10.1, including adding a rule, using the error inspector, and fixing a topological error.

http://wn.com/Basic_Topology_in_ArcMap

Differential Topology with Prof. John W. Milnor Lecture I

Order: Reorder
Duration: 55:38
Updated: 15 Aug 2013

http://wn.com/Differential_Topology_with_Prof_John_W_Milnor_Lecture_I

Where To Download The TSHOOT Topology From

Order: Reorder
Duration: 6:20
Updated: 10 Sep 2013

This CCNP Topology is the same topology across all the CCNP TSHOOT exam tickets, however each ticket has its own problem. This topology was provided publicly by Cisco and tickets were created randomly to help candidates out. Cisco's URL: https://learningnetwork.cisco.com/thread/10965 What's show in this series of videos is a list of tickets I created myself. These tickets can be used to strengthen your troubleshooting skills at the exam time. I'm yet to set my CCNP TSHOOT exam, so if I made any errors in explaining these videos, please excuse me :) Please download the entire GNS3 ZIP file from the link below. There is a total of 12 tickets in this series of videos. I will be creating few more tickets as ideas come to my mind, so be tuned :) https://dl.dropboxusercontent.com/u/20482/GNS3Talk_CCNP_TSHOOT_642-832_Topologies_and_Tickets.zip Enjoy them :) Regards

http://wn.com/Where_To_Download_The_TSHOOT_Topology_From