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Abstract

This study assessed the physico-chemical status of sediments in the Agbede Wetlands with the aim to create a reference archive for the Edo North catchment and to further identify the characteristics mostly influenced by the natural and anthropogenic activities going on at the watershed. Nutrients, zinc, nickel and lead were identified to be mostly of anthropogenic origin, while alkali metals and alkaline earth metals were from both anthropogenic and natural sources. The clustering of stations 1 and 4 indicates that the sediment quality in the lentic systems was not completely excluded from the lotic system, suggesting that principal component analysis (PCA) and cluster analysis (CA) techniques are invaluable tools for identifying factors influencing the sediment quality. The mean values of the particle size distribution were in the following order across the ecosystems: sand (61.86–80.53%) > silt (9.75–30.34%) > clay (7.83–13.89%). The contamination of the water bodies was primarily derived from agricultural run-offs and through geochemical weathering of the top soils. Therefore, our analysis indicates that the concentrations of cations, anions and nutrients in the sediments of the lotic and lentic ecosystems in Agbede Wetlands are not at an alarming level.

Abstract

This study assessed the physico-chemical status of sed­iments in the Agbede Wetlands with the aim to create a reference archive for the Edo North catchment and to further identify the characteristics mostly influenced by the natural and anthropogenic activities going on at the watershed. Nutrients, zinc, nickel and lead were identified to be mostly of anthropogenic origin, while alkali metals and alkaline earth metals were from both anthropogenic and natural sources. The clustering of stations 1 and 4 indicates that the sediment quality in the lentic systems was not completely excluded from the lotic system, suggesting that principal component analysis (PCA) and cluster analysis (CA) techniques are invaluable tools for identifying factors influencing the sediment quality. The mean values of the particle size distribution were in the following order across the ecosystems: sand (61.86-80.53%) > silt (9.75-30.34%) > clay (7.83-13.89%). The contamination of the water bodies was primarily derived from agricultural run-offs and through geochemical weathering of the top soils. Therefore, our analysis indicates that the concentra­tions of cations, anions and nutrients in the sediments of the lotic and lentic ecosystems in Agbede Wetlands are not at an alarming level.

Abstract

There are more than 522 towns and cities in Bangladesh, which generate thousands of tons of solid waste known as Municipal Solid Waste. Low collection coverage and disposal facilities are responsible for unsatisfactory waste management. The composting technology is a good alternative method for managing MSW. The present study was conducted to assess the quality of the MSW compost produced from the solid wastes of Mymensingh Pourashava. For quality assessment physical, chemical and biological properties of prepared compost namelye bulk density, porosity, water-holding capacity, moisture content, pH, organic matter content, C:N ratio, NPKS content, buffering capacity, soluble salts content, heavy metal content and the presence of harmful organisms in the MSW compost were studied. The results indicated that the MSW compost was matured and stable having pH 7.3 and buffering capacity of the MSW compost were good but the organic matter content and C : N (14.5) ratio were low. The N, P, K and S content of the MSW compost were 0.9, 0.3, 0.4 and 0.45 percent of the total volume. The soluble salts content and heavy metal content of the compost were found to be within the permissible limits. The MSW compost contained no E. coli and Salmonella. From the results, it can be concluded that, the composting could produce acceptable quality of compost, which can be used as fertilizer or soil amendment.

Abstract

Investigations on physicochemical parameters (temperature, pH, salinity, dissolved oxygen), including dissolved nutrients (PO4-P, NO3-N, SiO4-Si) and chlorophyll-a were carried out in the water off the mouth of the Narmada estuary from July 2008 to June 2009. The multivariate statistics and principal component analysis applied to the datasets, indicated two factors during the whole study period influencing variability in the water to the extent of 72%. Principal axis factoring and alpha factoring have been used to observe the mode of association of parameters and their interrelationships, for evaluating water quality. The results indicated the addition of phosphates and silicates to the coastal water by the Narmada estuary from natural sources during study period. The study indicated that the Narmada estuary adds sufficiently well-oxygenated, nutrient-rich water to the coastal region.

Abstract

The aim of the study was to determine the effect of these substitutions on body weight and slaughtering performance, post-mortem changes, sensory characteristics and chemical composition of selected muscle groups of male and female pheasants. The tests were carried out on pheasants during 5–16 weeks of rearing in enclosed aviaries. Four groups of 8 females and 8 males were formed, and the experimental factor was the supplementation of calcium, iron, zinc and copper salts with glycinates of these elements. The control group received a feed blend containing 100% of the mineral need as salts. In the E-25 group, 25% of the salts were replaced by glycinates, in the E-50 group 50% of the salts were replaced, and in the E-75 group only glycinates comprising 75% of the total mineral content were used and no salts were included, with vitamin D3 replaced by calcitriol. For the duration of the study, feeding was at will and the birds had free access to water. In addition, pheasants were weighed at the age of 4, 8, 12 and 16 weeks. Daily feed intake was monitored. At the end of the experiment, when all the pheasants were 16 weeks old, they were weighed and decapitated. The breast, thighs and drumsticks and the heart, liver and gizzard were removed from the chilled carcasses. Supplementation of calcium, iron, zinc and copper salts with 50% glycinates in feed mixtures for pheasants over a period of 5–16 weeks resulted in a slight improvement in the slaughter weight of birds and a significant increase in crude ash, calcium and zinc, while at 75% supplementation and when calcitriol was used instead of vitamin D3, increased phosphorus levels were found in the pheasant muscles analyzed. Males had higher body weight, body weight gain, carcass, liver and gizzard weights, and their muscles had more magnesium and potassium and less calcium, sodium and iron than females.

Abstract

The aim of this study is to discuss the water balance of Kopalińskie Lake, which is one of a few reservoirs on the Polish coast formed from anthropogenic activity. To realize this aim, lake basin morphometry and catchment hydrography were characterized. Moreover, the influence of the sea and the physico-chemical characteristics of the lake water were defined. As a result, the main characteristics of the lake and its catchment were found. Common characteristics of Kopalińskie Lake, as well as the characteristics that differentiate this reservoir from the other coastal lakes located on the Polish coast are presented in this work.

Abstract

Snail control as a form of integrated control for schistosomiasis has been strongly advocated but data on biocontrol using competitor snails are relatively lacking in most endemic areas. Monthly sampling of freshwater snails was conducted in four water bodies in Yewa North Local Government Area, Ogun State, Nigeria. Monthly in situ measurements of the physico-chemical characteristics of surface waters were carried out using field meters. A total number of 13 snail species were recovered from the water bodies. Of these, Bulinus camerunensis was reported for the first time in Nigeria. A significant positive relationship occurred between snail density and dissolved oxygen. Other important relationships were those between Lanistes lybicus and Bulinus senegalensis, Bulinus globosus and Bulinus jousseaumei, and B. senegalensis and Segmentorbis augustus. Snail control using competitor snails should be integrated into schistosomiasis management programmes in endemic areas in order to prevent residual schistosomiasis transmission after control intervention through mass drug treatment.

Abstract

This paper refers to the quality analysis of three dermo-cosmetic products: two face creams and a biphasic solution used for skin cleaning: a treatment cream for acne complexion, an anti-irritating soothing cream and a matifying purifying lotion. The following characteristics have been investigated: aspect, smell, colour, solubility, type of emulsion, stability test at certain temperatures (4°C and 40°C), pH, melting point, water, volatile substances and total fats contents, acidity, ester index, saponification index, iodine index, peroxide index, microbic carriage, metal traces (determined by ICP-MS method). All analysed dermo-cosmetic products have appropriate physico-chemical characteristics. The analyses made for determining the microbial charge have proven that the three dermo-cosmetic products do not contain any aerobic pathogen germens or micromicetes, Staphylococcus aureus and Escherichia Coli. The ICP-MS analysis has proven that the dermocosmetic products do not contain traces of Hg and Pb.

Abstract

Cayenne peppers (Capsicum annuum L.) were incorporated to ayran aiming to obtain a health promoting ayran with different flavour. The effects on the physico-chemical characteristics, antioxidant and phenolic capacity, counts of Streptococcus, Lactobacillus, yeast, moulds and coliforms, sensory and volatile compounds analysis were performed. Ayran samples with powdered peppers had significantly higher antioxidant and total phenolic contents than the ayrans with sliced pepper. Pepper addition increased Lactobacillus and Streptococcus counts compared to control ayrans. The dominant bacteria during the storage period (7.61-8.88 log CFU/ml) was Streptococcus. Panelists rated flavour, texture, appearance and color properties of ayran samples with sliced pepper similar to control samples. Ayran samples with 15% sliced peppers had the maximum overall scores.

Abstract

The aim of this paper is the study of physico-chemical properties of the chosen compounds, derivatives of 2-hydroxy-3-[2-(4-methoxyphenyl) ethylamino]propyl-4-[(alkoxycarbonyl)amino]benzoates and 2-hydroxy-3-[2-(2-methoxyphenyl)ethylamino]propyl-4-[(alkoxycarbonyl) amino]benzoates with potential ultra-short beta-adrenolytic activity. The studied compounds are different in the position of the substituent on the benzene ring in the side chain as well as in the aromatic ring in position 4 with alkyl- (methylto butyl-) carbamate. The physico-chemical characteristics, for example, lipophilicity, surface activity, adsorbability, acidobasic properties etc., are very important for the explanation of the relationship between structure and biological activity of the drug. These parameters serve as the base of quantitative structure-activity study. The goal of this work is to establish the spectral characteristics of studied compounds in UV-area, pKa values, the parameters of lipophilicity (the values of Rf and RM from thin layer chromatography, retention time t´R and capacity factor k´ from liquid chromatography and experimental partition coefficients log P´ values), surface tension, critical micelle concentrations, the adsorbability of compounds expressed by percent of adsorbed compound on active charcoal β% as well as by Freundlich adsorption isotherms. The obtained values are correlated with the parameters characterising the size of molecule, for example, the number of carbon atoms on carbamate functional group.