| Table_of_Numbers_Problem Given a m * n rectangle, place all numbers from 1 to mn that minimizes the sum of the products of rows and columns (both in Spanish and English). |
| Treasure_Troves___Book_List Book list including titles, authors, publishers, prices, page count and some have links to Amazon.com. |
| Wade_Edward_Philpott Profile and description of his mathematical games and puzzles. |
| Wade_Edward_Philpott_Collection A special collection at the University of Calgary Library. |
| Who_Can_Name_the_Bigger_Number? An essay by Scott Aaronson on the quest for ever-bigger numbers, from exponentials to Busy Beavers. |
| BBC_-_Genes Explore the world of genetics and investigate the issues. Features history, health, a gene safari, and DNA detectives. |
| BioScience_Research_Tool__Genetics Specialized directory of online tools and resources selected for geneticists. |
| Chromosome_Web_Watch Resource site for researchers. Includes links to conferences and courses, directories, laboratories, journals, and publishers. |
| Computational_Gene_Recognition Bibliography of accumulated research papers. Includes databases, programs, and conferences. |
| Cracking_the_Code_of_Life Chronicles the race to capture the complete letter-by-letter sequence . Includes an online version of the television program. Viewable in Quicktime or Real Audio format. |
| Database_of_Genome_Sizes Genome sizes for different organisms. The estimated genome sizes are given for both the organisms currently being sequenced and those for which no sequencing programme is in progress. |
| The_DNA_Files__Genetic_Science_Documentaries_Distributed_by_National_Public__Radio A public radio series that explores the world of genes and genetic science. |
| Essentials_of_Genetics Provides a range of notes including landmarks, basic terms and rules, chromosomes and genes, population genetics, viral and bacterial genetics, and plant genetics. Includes links to related resources |
| Gene_CRC Provides a range of information on the latest genetics research and ethical and associated issues. Features an interactive learning center, children's section, and related links. |
| Genetic_Origins Provides biochemical methods and computer tools to allow students to use their own DNA "fingerprints" as a starting point in the study of human evolution. |
| Genetics_Virtual_Library Comprehensive subject catalog covering genetics in the biosciences. Provided by the U.S. Department of Energy. |
| 123Genomes A genomics and bioinformatics knowledge base with information on companies, careers, courses, meetings, databases, sequence analysis, news, diseases, mutation, snp, and microarray. |
| Life__A_Study_of_Genetics_and_Molecular_Biology Source of information from the basics to contemporary issues such as cloning and cancer. Includes interactive demonstrations and a discussion forum. |
| The_National_Center_for_Biotechnology_Information A national resource for molecular biology information for the better understanding of molecular processes affecting human health and disease. |
| The_New_York_Times__Genetics Collection of articles assembled to commemorate the 50th anniversary of the discovery of DNA. Topics include history, recent developments, ethical concerns and other issues related to the genetic revo |
| Noncoding_DNA Explores the noncoding portion of the genetic code. Details raw data, research, updated values, and perspectives. |
| The_Selfish_Gene An introduction to genetics, covers the basics including cell mechanics, chromosome structure, genotypes and phenotypes, recombination, cloning and mapping. |
| Colloid_and_Interface_Science_Page Terms and field of colloid science, Laurier L. Schramm, University of Calgary. |
| Food_Rheology_Laboratory_-_USA,_MI Rheology applied to food process engineering. |
| Glossary_of_Rheological_Terms By the Institute for Non-Newtonian Fluid Mechanics. |
| Intro_to_polymers___The_Macrogalleria A cyberwonderland of polymer fun from University of S MS |
| Materials_Science_Modeling Project at NIST, Applied and Computational Mathematics Division, US gov. institute. |
| Mechanical_Properties_of_Polymers Viscoelasticity, relaxation spectra, Model of polymer chain .. |
| NIST__Materials_Science_-_Polymers_Division National Institute of Standards and Technology (US government): polymers - electronics materials, biomaterials, ... large site with searchable index |
| The_Origins_of_Rheology__A_Short_Historical_Excursion History and relationships with other areas of physics. [PDF] |
| The_Physics_of_Granular_Flows Flow of grains : experimental and numerical studies. |
| Polymers_Division_of_NIST The Polymers Division of US standards institute provides standards, measurement methods, and fundamental concepts for plastics industry |
| Prof__Clifford_Truesdell Publications, bio, .. of the 'Grand Man' of Rheology. |
| Rheology_of_Liquid_Crystals_-_Freiburg TMR Network - nematic fluids. |
| Rheology_Primer Understanding of hydrocolloids. |
| Rheology_Research_Center,_University_of_Wisconsin History, videos of rheologic processes, and links. |
| Suspensions Computational approach. |
| Transport_in_Permeable_Media Transport and phase change phenomena in porous media. |
| What_is_rheology_anyway? Rheology studies the flow of unusual materials, particularly non-Newtonian fluids such as mayonnaise, paint, molten plastics, and foams. The Society of Rheology caters to rheologists in many fields |
| Biosoft Programs for data analysis, graphics and statistics. |
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Recreational Mathematics?
That's right - recreational math; the passion of Sir Roger Penrose who was recently
knighted for his outstanding contributions to mathematics.
Roger Penrose, a professor of mathematics at the University of Oxford in England,
pursues an active interest in recreational math which he shared with his father. While
most of his work pertains to relativity theory and quantum physics, he is fascinated with
a field of geometry known as tessellation, the covering of a surface with tiles of
prescribed shapes.
Penrose received his Ph.D. at Cambridge in algebraic geometry. While there, he began
playing around with what appears to be a somewhat frivolous geometrical puzzle. He wanted
to cover a flat surface with tiles so that there were no gaps and no overlaps. There are
several shapes that will do the job, regular triangles, rectangles, hexagons, and so
forth. Or it can be done with combinations of shapes, resulting in a pattern that repeats
regularly. Penrose began to work on the problem of whether a set of shapes could be found
which would tile a surface but without generating a repeating pattern (known as
quasi-symmetry). It turned out this was a problem that couldn't be solved computationally.
So, armed with only a notebook and pencil, Penrose set about developing sets of tiles that
produce 'quasi-periodic' patterns; at first glance the pattern seems to repeat regularly,
but on closer examination you find it is not quite so.
Eventually Penrose found a solution to the problem but it required many thousands of
different shapes. After years of research and careful study, he successfully reduced the
number to six and later down to an incredible two.
These tiles are particularly intriguing to play with because you have to take into
account more than just the tile next door to decide how pieces fit together. Anyone can
have a go at this problem. Professor Penrose has designed a puzzle using this tiling
concept which is now available in the United States through Pentaplex. The puzzle consists of bird-shaped pieces
which are kept in play on a gameboard built into the box. Using just the two shapes, small
and large birds, the goal is to completely cover the playing surface. Sounds easy? It's
not, and there is only one solution. At higher levels you substitute a rogue dog for a
large bird and the solutions change. By the time you have five dogs substituted you'll
have gone through potentially 23 different solutions to just one puzzle.
While this may all sound rather far removed from life in the real world, it turns out
that some chemical substances will form crystals in a quasi-periodic manner. Professor
Penrose tells of a striking demonstration of the benefits of pure research - a French
company has recently found a very practical application for substances that form these
quasi-crystals: they make excellent non-scratch coating for frying pans.
Penrose was raised in a family with strong mathematical interests: his mother was a
doctor, his father, a medical geneticist, used math in his work as well as his recreation,
one brother is a mathematician, another was ten times British chess champion. Roger
originally was more attracted to medicine than math, but when forced to choose between
biology and math because of inflexible school scheduling, he was not willing to give up
the mathematics.
Roger and his father are the creators of the famous Penrose staircase and the
impossible triangle known as the tribar. Both of these impossible figures were used in the
work of Dutch graphic artist Maurits Cornelis Escher to create structures such as a
waterfall where the water appears to flow uphill and a building with an impossible
staircase which rises or falls endlessly yet returns to the same level.
In addition to the recent honor of knighthood, Professor Penrose was awarded the
prestigious Wolf Prize for Physics in 1988 which he shared with Stephen Hawking.
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