175 research outputs found
A Complete Formulation of Baum-Conens' Conjecture for the Action of Discrete Quantum Groups
We formulate a version of Baum-Connes' conjecture for a discrete quantum
group, building on our earlier work (\cite{GK}). Given such a quantum group
\cla, we construct a directed family \{\cle_F \} of -algebras (
varying over some suitable index set), borrowing the ideas of \cite{cuntz},
such that there is a natural action of \cla on each \cle_F satisfying the
assumptions of \cite{GK}, which makes it possible to define the "analytical
assembly map", say , as in \cite{GK}, from the
\cla-equivariant -homolgy groups of \cle_F to the -theory groups of
the "reduced" dual \hat{\cla_r} (c.f. \cite{GK} and the references therein
for more details). As a result, we can define the Baum-Connes' maps \mu^r_i :
\stackrel{\rm lim}{\longrightarrow} KK_i^\cla(\cle_F,\IC) \raro
K_i(\hat{\cla_r}), and in the classical case, i.e. when \cla is for
a discrete group, the isomorphism of the above maps for is equivalent
to the Baum-Connes' conjecture. Furthermore, we verify its truth for an
arbitrary finite dimensional quantum group and obtain partial results for the
dual of Comment: to appear in "K Theory" (special volume for H. Bass). A preliminary
version was available as ICTP preprint since the early this yea
Processing of fluted pumpkin seeds, Telfairia occidentalis (Hook F) as it affects growth performance and nutrient metabolism in rats
This study determined the nutrient and some anti-nutrient components in Telfairia occidentalis seeds. The work also evaluated the effects of processing on some of the anti-nutritional factors in the seeds as well as growth and animal metabolism. Fresh seeds of T. occidentalis were divided into three groups based on heat treatment: group 1, the unprocessed (raw) seeds; group 2, the under-processed seeds (heat-treated at 70oC for 30 min); and group 3, the processed seeds (cooked at 100oC for 1 hr). Seeds from each group were de-hulled, sun-dried and pulverized. Portions from each group were subjected to proximate composition analysis; trypsin inhibitor and lectin content were also measured in the seeds. The dried seed samples were incorporated into the diets of experimental animals. Twenty albino rats were randomly divided into four groups and fed with the control or experimental diets for a period of 21 days. During this period, body weights of the animals and feed intake were recorded daily and feces and urine were collected. At the end of experimental period, blood samples were collected from the animals for heamatological analysis, then the animals were sacrificed and some key organs were excised for histopathological analysis. Results showed that the seeds contained essential nutrients and that processing significantly affected the lectin and trypsin inhibitor (anti-nutrients) in the seeds. In comparison with control animals, the parameters measured which included body weight gain, nutrient digestibility, nitrogen balance, nitrogen retention and hematological parameters were markedly different among the three groups of animals fed diets incorporated with the seeds. Histopathological analysis indicated that the spleen and small intestines were adversely affected in the experimental animals. In conclusion, T. occidentalis seeds have high nutritive value, but could have deleterious effects in animals if ingested without adequate processing. It could, however serve as a high quality and low cost plant protein source for animal feed formulations provided adequate seed processing is ensured.Key words: seeds, anti-nutrient, processing, metabolism, growt
The Distribution of the Enzyme Arginase in the Tissues of Selected Cichlidae Species: Tilapia zillii, Sarotherodon galilaeus and Oreochromis niloticus
The paper reports the tissue distribution of the enzyme arginase in three different Cichlids: Tilapia zilli, Sarotherodon galilaeus and Oreochromis niloticus, from the Aiba and Osinmo reservoirs, located in the southwestern Nigeria. The tissues of S. galilaeus showed very high activity of arginase as compared with the other two species. The liver of O. niloticus and the gut of T. zillii showed very high activity of arginase in the Osinmo reservoir. The high arginase activity observed in the tissues of these organisms is attributed to ureotelism and is similar to the result obtained for tilapia, Alcolapia grahami, from lake Magadi, Kenya
Higher Algebraic K-theory for Twisted Laurent Series Rings Over Orders and Semisimple Algebras
Expression of bilitranslocase in the vascular endothelium and its function as a flavonoid transporter
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Isolation, characterization and immunochemical studies on fibrous proteins from cowry shell (Cypraea moneta, Linnaeus)
Background: Biomaterials are non-drug substances used to treat, enhance or replace functions of body tissues or organs. Natural sources of biomaterials have recently become the focus of several research activities. Cowry shell constitutes one of the most promising natural sources of biomaterials because of its chemical stability, biodegradability and biocompatibility in the body. However, its applications may be limited due to immunogenic and toxic responses that may occur following implantation, hence this study.Materials and Methods: Crude fibrous protein extracted with citrate buffer from pulverised cowry shells (Cypraea moneta (L)), was resolved into two components (CSP1 and CSP2) by gel filtration. Immunological studies were performed with antisera obtained from rabbits by double immunodiffusion and immunoelectrophoresis techniques. Mice treated with the proteins were observed for signs of toxicity and their liver, kidney, lungs and spleen were processed histologically.Results: The native molecular weight of CSP1 and CSP2 determined by gel filtration were 91kDa and 33kDa respectively. CSP1 and CSP2 displayed single bands on SDS-PAGE with subunit molecular weight values of 19kDa and 19.5kDa respectively. Antisera obtained from rabbits immunised with the crude citrate buffer extracts precipitated the antigen in double immunodiffusion tests. Histopathological examinations revealed a dose-dependent damaging effect of the shell proteins on liver, kidney, lung and spleen tissues of the treated mice.Conclusion: This study showed that cowry shells contain fibrous proteins which are immunogenic and toxic in mice at relatively high concentrations, causing visible organ damage without concurrent physical manifestations.Keywords: cowry shell protein, purification, immune activation, toxicit
Purification, characterization and toxicity of a mannose-binding lectin from the seeds of Treculia africana plant
In this study, a mannose-specific, homodimeric lectin from the seeds of Treculia africana was purified, characterized and its adverse effects were investigated in mice. The purification protocol involved anionic exchange chromatography on DEAE-Cellulose followed by gel filtration on Sephadex G-100. The hemagglutinating activity of lectin towards human erythrocytes was sensitive to inhibition by D-mannose. Treatment of the protein with EDTA exerted no inhibitory effect; however, analysis of metal content by atomic absorption spectroscopy revealed the presence of Cu2+, Fe3+, and Mg2+. The results obtained showed that the lectin possesses maximum hemagglutinating activity towards human erythrocytes activity over the pH range 3–7.2 and is relatively thermostable up to 50°C. Periodic acid Schiff's (PAS) reagent staining showed that the protein was non-glycosylated while its amino acid composition analysis revealed that the protein contained 155 residues per subunit. The subunit had a minimal molecular weight of 22,139 Daltons, while the native molecular weight was estimated to be 41,000 Daltons. The lectin was found to be moderately toxic to mice with an LD50 of 47.21 µg g−1 body weight while, histopathological analysis showed no treatment related effects in any of the organs examined
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