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1.
Stud Health Technol Inform ; 242: 843-850, 2017.
Article En | MEDLINE | ID: mdl-28873894

The implicit didactic information embedded in the theoretical part of math schoolbooks is one of the keys for successful learning mathematics, but mostly reserved for sighted students. Thus, the methodology for analyzing this theoretical part of selected math schoolbooks is developed for extracting this implicit didactic information, which will be made accessible. Combined with the blind students' teaching methods in classrooms, a dialog-based assistant concept is suggested for covering core didactics for teaching the blind.


Blindness , Mathematics , Self-Help Devices , Education , Humans , Students , Textbooks as Topic
2.
Stud Health Technol Inform ; 217: 27-31, 2015.
Article En | MEDLINE | ID: mdl-26294449

Equal access to education will foster a knowledge society for all. In particular for the ICT based information society a benchmark has been set to raise the numbers of graduates in science, technology, engineering and mathematics (STEM) study courses by 15% (748.000) per year, asking for increased efforts in Europe (http://ec.europa.eu/education/policy/strategic-framework/index_en.htm). This holds even more true for people with disabilities who a) participate in and graduate from STEM at a much lower number and b) face a much higher unemployment rate, in particular in STEM related fields. This asks for sound and well-founded education - first and foremost in math - for people with disability and here especially for blind people.


Education of Visually Disabled/methods , Engineering/education , Mathematics/education , Science/education , Teaching/organization & administration , Technology/education , Austria , Educational Technology , Humans , Teaching/standards
3.
Stud Health Technol Inform ; 217: 227-34, 2015.
Article En | MEDLINE | ID: mdl-26294477

Developing resources for online learning in its many guises and more recently for MOOCs has been discussed across the educational sector, usually by individuals working for one institution or organisation. Rarely are there discussions that highlight the issues of collaborative working on content that is delivered over a period of weeks for a wide range of abilities and skills. In particular there is a reluctance to face the issues presented by barriers to access for those with disabilities and even the issues that could arise should an academic be unable to access the development platform to present content. This paper aims to approach these issues by providing guidance in a series of practical steps that highlight an inclusive design approach.


Computer-Assisted Instruction , Education, Distance/methods , Online Systems , Educational Technology , Ergonomics , Humans , Multimedia , User-Computer Interface
4.
J Phys Chem A ; 118(8): 1293-9, 2014 Feb 27.
Article En | MEDLINE | ID: mdl-24491182

The chlorine dioxide-pentathionate reaction has been studied at a slightly acidic medium by conventional UV-vis spectroscopy monitoring the absorbance at 430 nm. We have shown that pentathionate was oxidized to sulfate, but chlorate is also a marginal product of the reaction besides the chloride ion. The stoichiometry of the reaction can be established as a linear combination of two limiting stoichiometries under our experimental conditions. Kinetics of the reaction was found to be also complex because initial rate studies revealed that formal kinetic orders of both the hydrogen ion and chlorine dioxide is far from unity. Moreover, log-log plot of the initial rate against pentathionate concentration indicated a nonconstant formal kinetic order. We also observed a significant catalytic effect of chloride ion. Based on our observations and simultaneous evaluation of the kinetic curves, an 11-step kinetic model is obtained with 6 fitted rate coefficients. A relatively simple rate equation has also been derived and discussed.

5.
Phys Chem Chem Phys ; 12(10): 2356-64, 2010 Mar 14.
Article En | MEDLINE | ID: mdl-20449348

It is experimentally proven that the stoichiometry of the tetrathionate-chlorite reaction is 2S4O(2-)6 + 8(1/2)ClO-(2) + 6H2O = 8SO(2-)4 + ClO-(3) + 7(1/2)Cl- + 12H+ near 1:4 molar ratio of the reactants. Re-evaluation of the previously measured front velocity--concentration curves also shows that this stoichiometry along with both the rate equation r = (1.6 x 10(5) M(-3) s(-1) [H+]2 + 3.6 x 10(7) M(-4) s(-1) [H+]3)[S4O(2-)6][ClO-(2)] and the protonation processes existing in the present system allow us to describe the front velocity as a function of the initial concentration of the reactants quantitatively. Some consequences detailed in the conclusions may concern not only uniquely the tetrathionate-chlorite reaction but any front propagation study including H+ as an autocatalyst.


Chlorides/chemistry , Models, Chemical , Tetrathionic Acid/chemistry
6.
Histochem Cell Biol ; 123(4-5): 357-63, 2005 Jun.
Article En | MEDLINE | ID: mdl-15856274

Chemically modified albumin binds to the surface of microvascular endothelia lining the vessel wall in several tissues. In this paper, we report that following their biotinylation, ovalbumin (bioOVA) and bovine serum albumin (BSA) [biotinyated albumin (bioAlb)] showed heterogeneous binding to distinct vascular subsets in different lymphoid tissues. The binding of bioAlb could be demonstrated both by fluorescent and enzymohistochemical techniques. In the spleen, the reaction was restricted to the red pulp sinuses whereas the white pulp vessels (including the central arteriole) and the marginal sinus were negative for bioAlb binding. In lymph nodes, the strongest labeling was observed in the medullary sinuses. In the thymus, the most prominent labeling of capillaries was restricted to the corticomedullary area where it was found to be less intense compared with the splenic reaction. The splenic reactivity of bioAlb in the mouse was defined using antibodies against endothelial cell subsets in distinct vascular beds in the red pulp and marginal zone, respectively. The bioAlb-binding elements of the splenic red pulp sinus architecture corresponded to the display of hyaluronan receptor stabilin-2 and subset-specific marker IBL-9/2 while they differed from the expression pattern of both the complementary red pulp sinus subset and the marginal sinus-lining cells expressing MAdCAM-1 antigen, respectively. Similar red pulp sinus-restricted reactivity could be demonstrated in the human, rat, and guinea pig. The use of bioAlb may thus offer a reliable probe for the histological identification of select microvascular endothelia in lymphoid tissues.


Endothelium, Vascular/metabolism , Lymphoid Tissue/blood supply , Ovalbumin/metabolism , Animals , Binding, Competitive , Biotinylation , Cattle , Cell Adhesion Molecules , Cell Adhesion Molecules, Neuronal/analysis , Female , Immunoglobulins/analysis , Lymphoid Tissue/cytology , Mice , Mice, Inbred BALB C , Microscopy, Fluorescence , Mucoproteins/analysis , Serum Albumin, Bovine/metabolism , Spleen/blood supply
7.
J Inorg Biochem ; 98(10): 1591-8, 2004 Oct.
Article En | MEDLINE | ID: mdl-15458821

Polynuclear platinum compounds demonstrate many novel phenomena in their interactions with DNA and proteins as well as novel anti-cancer activities. Previous studies indicated that the high positive charge and the non-coordinated "central linker" of the polynuclear compounds could have major contributions to these features. Therefore, a series of non-covalent polynuclear platinum complexes, [[Pt(NH(3))(3)](2)-mu-Y](n+) (Y=polyamine linker or [trans-Pt(NH(3))(2)(H(2)N(CH(2))(6)NH(2))(2)]) was synthesized and the DNA interactions of these platinum complexes were investigated. The conformational changes induced by these compounds in polymer DNA were studied by circular dichroism and the reversibility of the transition was tested by subsequent titration with the DNA intercalating agent ethidium bromide (EtBr). Fluorescent quenching was also used to assess the ability of EtBr to intercalate into A and Z-DNA induced by the compounds. The non-covalent polynuclear platinum complexes induced both B-->A and B-->Z conformational changes in polymer DNA. These conformational changes were partially irreversible. The platinum compound with the spermidine linker, [[Pt(NH(3))(3)](2)-mu-spermidine-N(1),N(8)]Cl(5).2H(2)O, is more efficient in inducing the conformational changes of DNA and it is less reversible than complexes with other linkers. The melting point study showed that the non-covalent polynuclear platinum complexes stabilized the duplex DNA and the higher the electrical charge of the complexes the greater the stabilization observed.


DNA/chemistry , DNA/metabolism , Nucleic Acid Conformation , Platinum Compounds/chemical synthesis , Platinum Compounds/metabolism , Circular Dichroism , Ethidium , Magnetic Resonance Spectroscopy , Molecular Structure , Nucleic Acid Denaturation , Platinum/chemistry , Platinum Compounds/chemistry , Polyamines/chemistry , Spectrometry, Fluorescence , Temperature , Thermodynamics
8.
Steroids ; 67(9): 777-81, 2002 Aug.
Article En | MEDLINE | ID: mdl-12123789

17-formyl-androst-16-ene and its analogues were synthesized from the corresponding 17-iodo-16-ene derivatives in palladium-catalyzed formylation reaction using tributyltin hydride as hydrogen source under mild reaction conditions. The formation of androst-16-ene and its isomerization products, as well as that of analogous steroidal olefins as side-products, was found to be dependent on the reaction conditions. The formylation reaction tolerates various functional groups on the A and B rings of the steroids.


Palladium/chemistry , Steroids/chemistry , Steroids/chemical synthesis , Catalysis , Molecular Structure , Structure-Activity Relationship
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