Rivers State University of Science and Technology

About: Rivers State University of Science and Technology is a education organization based out in Port Harcourt, Rivers, Nigeria. It is known for research contribution in the topics: Population & Threatened species. The organization has 1826 authors who have published 1833 publications receiving 15183 citations.

Isolation of an isoflavonoid and a terpenoid from the heartwood of Baphia nitida Lodd. (camwood)

Abstract: Chromatographic separation of methanolic extract of Baphia nitida heartwood gave two crystalline solids characterized as 3,9-dimethoxy-6aR,11aR-dihydro-6H-benzofuro(3,2-C)[1]benzopyran (also known as homopterocarpin) with molecular formula C₁₇H₁₆O₄ (1.57% yield) and 2,4-dimethoxybenzaldehyde C₉H₁₀O₃ (2.27% yield). Each of the isolated compounds showed a single spot on developed thin layer chromatographic plate under ultra-violet light (254 nm) and spray reagent (10% sulfuric acid in methanol solution). Structural elucidation was achieved using Fourier transform infrared (FT-IR) spectroscopy, one and two-dimension nuclear magnetic resonance (NMR) techniques. Distortionless enhancement by polarization transfer-edited-heteronuclear single quantum coherence (DEPT-ed-HSQC) was also a useful tool that aided the characterization of the two secondary metabolites isolated from Baphia nitida heartwood.

Metal-Nitrogen Bonding in 1-Phenyl-3-Methyl-4-Acylpyrazolone-5 Complexes of Lead(II): Synthesis and Spectroscopic Studies

Abstract: Synthesis, electronic, infrared and NMR spectral studies were carried out on a series of 4-acyl-3-methyl-1-phenylpyrazolone-5 complexes of lead(II). They showed that both Pb-O and Pb-N bonds were present in the complexes. Subsequently, the complexes were characterized as lead(II) bis-chelates with octahedral structures through Pb-N bond linkages. The frequency of the Pb-O vibrations were observed to decrease with increase in length of 4-acyl substituent. Referee I: G. L. Gould Referee II: R. M. Richman

Regional Economic Communities and Human Rights in West Africa and the African Arabic Countries

Abstract: This paper examines the human rights mandate of regional economic communities which exist among West African and African Arabic Countries such as - ECOWAS (Economic Community of West African States); WAEMU (West African Economic and Monetary Union (WAEMU); The League of Arab States; (AMU)The Arab Magreb Union and TCEN-SAD) the Community of Sahel-Saharan States.

Factors Affecting Seedling Emergence and Dry Matter Characteristics in Musa balbisiana Colla

Abstract: The effects of storage duration (0, 2, 4, 6, 8, and 10 days), sterilization with sodium hypochlorite (0, 5, 10, 15, and 20%), and weaning media on seedling characteristics and dry matter content in Musa balbisiana seedlings were studied. The experiment was factorial in a completely randomized design with five replicates. The result indicates that increase in NaOCl concentration and number of days in storage significantly increased the period of seedling emergence. Also, soaking in NaOCl for 20 min had significant effect on average seedling emergence at 15 and 20% concentrations, compared to 10 min soaking at the same concentrations. The combined effects of storage duration and sterilization resulted in a decrease in the duration of seedling emergence. Seeds previously sterilized with either water or NaOCl had no significant effect on seedling growth, leaf and corm dry weight, but affected almost all the dry matter traits. A mixture of poultry manure, top soil, and river sand as weaning media gave better seedling growth and increased dry matter characteristics. We conclude that M. balbisiana seeds require after-ripening treatment to enhance germination, sterilizing seeds with 5% NaOCl for 10 min and air-drying under ambient condition for 2–6 days were found most appropriate, and a mixture of poultry manure, top soil, and river sand is recommended as weaning medium for growth and dry matter composition in M. balbisiana seeds.

Sighting frequency decreases over two decades in three populations of Testudo hermanni from central Italy

Abstract: Sighting frequency of tortoises (Testudo hermanni), standardized by the number of person-hours of field effort, was studied between 1992 and 2013 at three different study areas in central Italy. Although the frequency of tortoise sightings fluctuated substantially across years and among study areas, there was a significant declining trend in all the three areas, with GLM analyses showing also a significant interaction between study area and sampling year. The decreasing trend was higher in Castel Fusano than in the other two sites, with yearly frequency of sightings being independent of search effort in all of the study areas. These trends may indicate population declines, because no other explanations seem plausible. Total rainfall from previous autumn to the study period was positively correlated to tortoise sightings in only one locality. The yearly frequency of sightings of juvenile tortoises did not vary significantly among study areas and across years, thus indicating that simple differences in detectability cannot explain the observed patterns. Summer fires and forest overgrowing seem to explain the tortoise decline in two study areas (Castel Fusano and Oriolo) whereas we were not able to identify any specific reason for tortoise decline in the third study area (Manziana).