Book review by Prof. Manuel Alberto M. Ferreira
Game Theory (A Multi-Leveled Approach)
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Michael F. Shaughnessy, Juchao Yan, William Cooper
Teaching science, chemistry and biology at the college/university level
When college students arrive in science classes, some are woefully unprepared, some are minimally prepared, and some, while well educated in high school have forgotten many of the basics in terms of basic science, basic scientific reasoning, and basic scientific procedures. This paper examines some of these issues, reviews some of the main areas of concern and delves into issues of formative evaluation and the issue of pre-requisite courses.
Nna Prince Joe, Nwineewii Jack Dumka
Occurrence and sources of Pentacyclic Triterpenol methyl ethers and alkanones as molecular indicators in suspended particulate matter from Great Kwa River, Southeast Nigeria
Occurrence and source identification of Pentacyclic Triterpenol methyl ethers and alkanones as molecular indicators in suspended particulate matter obtained during high and low tides from Great kwa River, South East, Nigeria were characterized using gas chromatography- mass spectrometry (GC-MS) technique. Pentacyclic Triterpenol methyl ethers (PTMEs), taraxer-12-en-3-one, taraxer-14-en-3-one, taraxerone, taraxerol, miliacin, β-amyrin methyl ether, α-amyrin methyl ether, β-amyrenyl acetate, α-amyrenyl acetate and friedelin were characterized in the suspended particulate matter. Alkanones such as 6,10, 14-trimethyl pentadecan-2-one, pentacosan-2-one, heptacosan-2-one, octacosan-2-one, nonacosan-2-one, triacontan-2-one, hentriacosan-2-one, dotriacotan-2-one and tritriacotan-2-one were also found. These distinct compounds are useful for assessing diagenetic transformation that occurs during transportation of organic detritus. PTMEs are biomarkers of specific higher plants species, while alkanones are indication of direct microbial oxidation of the n-alkanes derived from epicuticular vascular plant wax. The presence of taraxerol and its ketonic counterpart taraxerone in the sample was an indication of dominant inputs from the study area vegetation and also reflect the oxidation and direct biological inputs. The accumulation of these compounds during low tide than high tide was due to sedimentation and oxidative process of the organic matter.
V.N. Osabor, Itam Asukwo Essien
Paleoenvironmental interpretation of clay deposits within Odukpani, Southeastern Nigeria
Clay geochemical and mineralogical composition in Odukpani area, Southeastern Nigeria was analyzed from 10 different locations in order to infer its importance as paloenvironmental indicator. The results show variation in major elements and mineralogical composition. Chemical data showed the average values of silica (SiO2), alumina (Al2O3) and hematite (Fe2O3) as 47.46% (46.79- 49.51)%, 34.08% (32.2-35.37) % and 2.79% (2.15-2.62)% respectively, while kaolinite being the most dominant mineralogical constituents has its average value as 88.10% (83-89)%. The high occurrence and concentration of SiO2 and Al2O3 infer terrestrial processes, while the low occurrence of TiO2 (less than 0.001%) and P205 (0.0267%) concentration may be due to claystone associated with continental processes. The mean value of illite / kaolinite ratio is 0.069 (ranges from (0.042-0.091), with higher concentration of kaolinite over illite indicate sediments of fluvial environment and this ratio in the presence of hematite shows oxygenated environment in an arid climate. A very low concentration of CaO (0.04%), MgO (0.19%) and K20 (0.61%) infer non marine influence.
Keywords: Clay geochemical, Odukpani area, paloenvironmental, terrestrial processes, illite/kaolinite ratio
Frank N.I. Morah, Etobong U. Udofia
Effect of Spilanthes filicaulis leaf extract on the survival rate of Nile tilapia, Oreochromis niloticus Abstract
Spilanthes filicaulis is an annual weed and medicinal plant which has insecticidal activity. The present work is focused on its effect on the survival rate of the Nile tilapia, Oreochromis niloticus. Introduction of Spilanthes filicaulis leaf extract into the aquarium resulted in erratic swimming, loss of reflex, de-colorization and eventually death of the fishes. Mortality rate increased with increase in concentration of the plant extract.