| Cloning_of_Human_Stem_Cells_Speeds_Up Introduction to article updating work on patient specific cloning of stem cells for applications in diabetis, in Seoul National University, South Korea. [article retracted from Science Magazine] |
| UK_Scientists_Clone_Human_Embryo Report on research involving introduction of DNA from embryonic stem cells, surviving in egg genome from 11 women, for three to five days, the country's first patient specific cells. Publication due i |
| Embryonic_Stem_Cells_Isolation Announcement of successful isolation of human embryonic stem cells [ESCs, pluripotent cells] (November 6, 1998) |
| Apsidium__Bohrium Basic information and atomic structure. |
| Berkeley_National_Laboratory__Bohrium An article about an effort to determine the volatility of this element. |
| Borhium Historic information. |
| ChemicalElements_com__Bohrium Basic information, atomic structure, and isotopes. |
| EnvironmentalChemistry_com__Bohrium Atomic structure, chemical and physical properties, and isotopes. |
| It\'s_Elemental__Bohrium Basic physical and historical information. |
| LANL__Bohrium Basic information and history. |
| Lenntech__Bohrium Basic chemical properties. |
| Visual_Elements__Bohrium Image, source, general and physical information, and ionisation energies. |
| WebElements__Bohrium Information on history, isolation, and properties. |
| Caucasian_Languages Brief profile and list of languages, some with links to further information. |
| Circassian_language_online_lessons Description of Circassian phonetics and main grammar forms, English-Circassian phrasebook. |
| Ergative_Case_in_the_Circassian_Languages Paper examining the marking of ergative/absolutive case in various types of nominals subsequently relating their distribution to the nominal hierarchy. |
| The_Lezgian_Language_Site Introduction to the Lezgian language (grammar, conversation) with basic information about the Lezgians. |
| Long-Distance_Agreement_in_Tsez Article by Eric Potsdam and Maria Polinsky, discussing cases of agreement extending beyond the clause. |
| Udi_Online_Grammar Online grammar of Udi, spoken in Northern Azerbaijan and Eastern Georgia. Contains grammatical description, samples of Spoken Udi, text collection with interlinear glosses and translation, and bibliog |
| Ancient_DNA_May_be_Misleading_Scientists From News in Science. Ancient DNA in skeletons has a tendency to show damage in a particular region resulting in misleading genetic data and mistaken conclusions about the origin of the skeleton Brit |
| Haemotaphonomy Brief overview of research on red blood cell morphology in bloodstains and its application to archaeology and paleoanthropology. |
| Paleopatologia Pisa University Division of Paleopathology sponsored board of articles and forum on the study of disease from prehistory to contemporary age. |
| South_Dakota_Paleopathology A paleopathology online database including material from the W.H. Over Collection of the University of South Dakota and the Crow Creek Massacre totaling over 400 images with descriptions. |
| New_Scientist__Ancient_Ancestors_had_Tummy_Bug_Too The stomach-infesting bacterium Helicobacter pylori has been living in humans for at least 11,000 years - much longer than previously thought, say US researchers. (November 4, 2002) |
| 27ACCMCC 27th Australasian Conference on Combinatorial Mathematics and Combinatorial Computing. The University of Newcastle, Australia; 9--13 December 2002. |
| ACCMCC-23 23rd Australasian Conference on Combinatorial Mathematics and Combinatorial Computing. Brisbane, Australia; 6--10 July, 1998. Conference report. |
| ALCCAL_2000 Algebraic Combinatorics and Computer Algebra Summer School. Varna, Bulgaria; 3--14 September 2000. |
| Algebraic_Combinatorics_and_Applications Gößweinstein, Germany; 12--19 September 1999. |
| ANALCO04 The First Workshop on Analytic Algorithmics and Combinatorics. Held in conjunction with ALENEX04 and SODA04. New Orleans, LA, USA; 10 January 2004. |
| Asymptotic_Combinatorics_with_Applications_to_Mathematical_Physics Summer school surveying recent progress in the asymptotic theory of Young tableaux and random matrices from the point of view of combinatorics, representation theory, and the theory of integrable syst |
| AWOCA_2002 The Australasian Workshop on Combinatorial Algorithms, hosted by the University of Queensland. Kingfisher Bay Resort, Fraser Island, Queensland, Australia; 7-10 July 2002. |
| BCC16 Sixteenth British Combinatorial Conference. Queen Mary and Westfield College, University of London, UK; 7--11 July 1997. Abstracts, problem lists. |
| BCC18 18th British Combinatorial Conference. University of Sussex in Brighton, Falmer, Brighton, UK; July 1-6, 2001. |
| BCC19 The 19th British Combinatorial Conference. Bangor, Wales, UK; 29 June -- 4 July 2003. |
| BCC2005 20th British Combinatorial Conference. Durham, UK; 10--15 July 2005. |
| BCC_-_Past_Conferences This page provides information about each of the BCC series of conferences. |
| Big_Sky_Conference_on_Discrete_Mathematics University of Montana, Missoula, MT, September 7-9, 2000. |
| Brazilian_Symposium_on_Graphs,Algorithms_and_Combinatorics Fortaleza, Ceará State, Brazil; 17--19 March 2001. |
| CAAN_04 Workshop on Combinatorial and Algorithmic Aspects of Networking. Banff International Research Station (BIRS), Alberta, Canada; 5--7 August 2004. |
| Classical_Combinatorics In honor of Dominique Foata's 65th birthday. Temple University, Philadelphia, PA, USA; 7--9 July 2000. |
SpiralGalaxiesGalaxies come in a variety of shapes, with the shapes depending in a waynot yet completely understood on the evolution of the galaxies. More than half of all observed galaxies are spiral galaxies. Examples of Spiral GalaxiesThe figure below right shows anice spiral galaxy, M100,which is in theVirgo cluster Another beautiful example of a spiral galaxy isM83. Presumably our own galaxy would resemble these galaxies in appearanceif we could view it from the outside.The below left image shows a class Sc spiral galaxy M101 (NGC 5457; also called the Pinwheel Galaxy), which lies at a distance of about7 Mpc or 22 million light years(Ref).The image shown adjacent leftis of the spiral galaxy ESO 269-57, which is in the southern constellationCentaurus(Ref).The galaxy is oftype is Sa(r), with a recessionalvelocity of just over 3100 km/sec, implying by the Hubble Law a distance of about 155 millionlight-years. Its angular size is over 4 arcmin, corresponding to to a diameter ofabout 200,000 light-years.This spiral has a complex structure, with an inner ring-like set of tightly wound arms surrounded by outerarms that may be split into branches. It has prominent blue star-forming regions in the spiral arms.Properties of Spiral GalaxiesThe range of masses for spiral galaxies is ~ 109 - 1012 solar masses, with the typical mass being ~ 1011 solar masses. The typicalrange of luminosities corresponds to absolute blue magnitude -16 to -23, and thetypical diameter of the visible disk is 5-100 kpc.The Spiral StructureThe spiral structureis associated with active star-forming regions. As already noted inconjunction with the Milky Way, This is infact why the spiral arms of these galaxies are so prominent: because they areregions of active star formation, there are many hot young blue and blue-whitestars there, making the spiral arms extremely visible. The adjacent image shows a star-forming region in the spiral arms of the galaxy M31 (Andromeda) calledNGC 206(Ref). Notice the diffuse blue glow associated with many young stars.In constast the nucleus ofa spiral galaxy is typically much more red in color, often resembling ellipticalgalaxies; this indicates the presence of many old stars in the nucleus of spiralgalaxies.Here is a movie sequence of a galaxymorphing its perceived shape from spiral toalmostelliptical as the wavelength is varied. The image shown below illustrates rather clearly thespiral structure for several spiral galaxies classified according to their Hubble class. These images weretaken in UV light with the Ultraviolet Imaging Telescope aboard the Space Shuttle Columbia. Because thespiral arms are dominated by hot young stars, they stand out particularly well when photographed at UVwavelengths, since only hot young stars can produce much UV(Ref). In these images we can see clearly the progression to more tightly wound spirals as we move from Sc throughSb classifications. Gas and DustSpiral galaxies are rich in gas and dust, which is often visible as lanes ofdust when viewed from the "top" or "bottom", and as layers of dust when viewedfrom the side. In our own Milky Way the center of the galaxy is invisible from our vantage pointbecause the interstellar dust between us and the center (in Sagittarius) is so thick. 
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