Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Mineralium deposita 33 (1998), S. 283-297 
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The kaolin deposits of the Amazon region of Brazil are of lateritic origin, modified by subsequent reduced lacustrine and/or swamp environment. They are contemporaneous with lateritic bauxites found in the same region, all formed from aluminium silicate rocks. These are principally sedimentary rocks from the Cretaceous period (Itapecuru and Alter do Chão), but also include metamorphic and felsic volcanic rocks. After erosion of the upper part of these profiles they became locally a substratum for swampy and/or lacustrine environments mostly developed over the clayey saprolitic horizon where kaolin occurs. The saprolitic horizon is made up mainly of iron-mottled kaolinite which has been subject to an intense deferrification, which has increased the kaolin brightness and thickness. The kaolins are basically made up of well-crystallized kaolinite, quartz, sometimes illite-muscovite, anatase and hematite. In certain locations, crandallite-goyazite is also present. The deposits studied differ from each other in the mineral content levels, concentration of principal elements and in trace element distribution. The greatest quantity of quartz and, consequently SiO2, is intrinsically related to the type of parent rock. Small sedimentary deposits occur in alluvial flood plains located not very far from the lateritic source.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 30 (1996), S. 353-360 
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Collagens may be used as biomaterials for soft tissue reconstruction, e.g., the abdominal wall. We previously developed a biocompatible dermal sheep collagen (DSC), which in an abdominal wall reconstruction model showed controlled biodegradation and functioned as a matrix for ingrowth of fibroblasts but not of muscle. It was hypothesized that regeneration of muscle via DSC may be possible by seeding of muscle cells. Using a syringe, mouse C2C12 myoblasts were seeded in DSC disks and incubated in methylcellulose-based growth medium, changed at 24 h into differentiation medium. An estimated 85% of the cells were well distributed, especially in the top half of the DSC disks. Some 15% of the cells ended up on top. At 4 h, all cells showed a spherical morphology, sometimes with clear adhesion plaques. At 24 h, cells on the top started to form a “capsule” with well-spread cells. Underneath the capsule, of the remaining 85% of the cells, approximately 30% showed adhesion and spreading on/in between collagen bundles. At day 3 after the addition of differentiation medium, the spread cells showed first indications of myotube formation. At day 7, myotube formation had proceeded, while extracellular matrix, i.e., collagen and elastin, had been deposited. This study shows that myoblast seeding into DSC is feasible, resulting in a reasonable cell distribution and survival of 45% of the cells. The surviving cells are able to differentiate into myotubes and form an extracellular matrix. © 1996 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...