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Iroanya Onyekachi Ogbonnaya, Egwuatu Tochukwu Frank, Sonaike Adeola Olasubomi and Uwaezuoke Nduka David

Abstract

Identification of dismembered bodies recovered in disasters or crime scene is very important in forensic. This study was carried out to ascertain if foot size, body weight, height, stature and BMI can be used to predict sex using tape rule and Stadiometer scale. 150 subjects between 18 - 25yrs were recruited. Independent T-test, Pearson Correlation, Linear and Multiple Regression Analysis were determined using SPSS version 23. All measurements were higher in male than female and there was significant (p≤0.05) difference in the sex. The average foot length of 257.39mm was used to determine sex of the subjects. All foot lengths ≤ 257.39mm were presumed to belong to females while all values > 257.39mm was presumed males. Foot size and weight had the highest correlation values. Foot length gave better estimation of sex than foot breadth, BMI and weight. Results of Multiple regression equation was better than linear regression equation. In forensic anthropology, foot size has been used to predict sex. Limitation of this study is the formulae generated can only be applied to Nigerians aged 18-25 yrs. Studies should be carried out on diverse population for future inferences

Open access

G. Mecheri, S. Hafsi and N. Gherraf

Abstract

The objective of the present work is to prepare and characterize a porous material using quite particular and localized dunar sand (erg) of the desert near the El-Oued (south-east of Algeria). The porous material is prepared according to the mechanism of co-operative self-assembly. The method consists of polymerizing a silicic precursor (sodium silicate obtained by alkali fusion of sand with the sodium carbonate) around micelles of surfactant in an acid aqueous solution according to the sol-gel process. The elimination of the surfactant by calcining at high temperature leads to the final material which was characterized by XRF, XRD, MEB-EDX, FTIR and BET techniques.

Open access

Djamila Maanani, Narimane Segueni, Salah Rhouati, Yavuz Selim Çakmak, Maltem Asan-Ozusaglam, Abdghani May, Amar Zellagui and Salah Akkal

Abstract

This study was carried out to determine the phenolic contents as well as to evaluate the antioxidant and antimicrobial activities of Genista microcephala. Total phenolic and flavonoid compounds were quantified. Antioxidant activity was evaluated by various in vitro tests, including Ferric Ion Reducing Activity (FRP), Cuprac Ion Reducing Antioxidant Capacity (CUPRAC), and total antioxidant capacities (TAC). The antimicrobial activity of ethyl acetate and butanolic extracts of G. microcephala in addition of fatty acids content of different parts of the studied plant was evaluated against human pathogenic bacteria, fish bacteria and two yeast. The used methods were agar diffusion method and the determination of minimal bactericidal and fungicidal concentrations (MBC and MFC). No significant difference was found between the two used solvents on total phenolic content (TPC). While, difference in total flavonoid content (TFC) were found to be significant. Ethylene acetate extract was the most actif regarding antioxidant assay. The tested activity seems to be due to the high content of this extract on isoflavonoids. The tested extracts demonstrated the lowest inhibition concentration for B.cereus RSKK 863.

Open access

Nikolay Uzunov, Michele Bello, Laura Melendez-Alafort and Laura De Nardo

Abstract

In recent years, there is a constantly increasing interest in the application of nanoparticles for cancer diagnosis and cancer therapy. In this respect, the most promising nano-objects at present are the gold nanoparticles. A very convenient and powerful property of these objects is their ability to increase their temperature under electro-magnetic irradiation with certain wavelength. In our research we have directed our efforts toward particular nano-objects specifically sensitive to electromagnetic radiation in the near-infrared region (NIR). In order to study the photothermic properties of the solutions of gold nanoparticles in the NIR we constructed a specific electronic setup consisting of a laser system with interchangeable laser diodes with different wavelength NIR light, a thermally-insulated cuvette-holder compartment with temperature measuring probes and a NIR spectrometer to control the stimulated fluorescence emission of the nanoparticles’ solutions. The temperature measurement compartment with the thermal-insulated cuvette holder was designed to maintain the solutions’ temperature at a fixed value right before the moment of laser irradiation. To maintain the measurement setup at a fixed temperature before the irradiation we used a thermal stabilized system based on two Peltier cells with electronic temperature control. The temperatures of the ambient air and the temperature of the cuvette walls were continuously measured in order to make corrections about the temperature dissipation during the irradiation.

Open access

Vanya Koleva, Teodora Koynova, Asya Dragoeva and Nikolay Natchev

Abstract

Anthropogenic activities cause environmental pollution and alter biogeochemical cycles. Soils in cities and their vicinity are exposed to different pollutants. Nature Park Shumen Plateau is a protected area situated in the proximity of Shumen (Bulgaria). The aim of this research was to compare elemental composition of surface soil samples from Nature Park with two areas in Shumen city.

Soil samples from seven sites on the territory of Nature Park and from two urban sites were collected. The elemental composition of the samples was determined using Energy Dispersive X-Ray Fluorescence technique. Principal component analysis and cluster analysis were performed to interpret the complex data.

The content of 24 elements was determined: Br, Y, Zr, Mo, Ag, Cd, Sn, Sb, I, Cs, Ba, La, Ce Si, K, Ca, Ti, Mn, Fe, Cu, Zn, Rb, Sr, and Pb. Results presented here and previously showed that concentrations of heavy metals Cu, Zn, Cd and Pb are below the upper limit according to Bulgarian legislation. Concentrations of Mn and Fe in samples from Nature Park were comparable to the literature data reported for unpolluted areas. Principal component analysis and cluster analysis show similarity of the content of 24 elements between samples from Nature Park and from Shumen city. These findings are in accordance with our previous positive results from Allium-test: cytogenetic endpoints showed a presence of harmful compounds in Nature Park soils.

The content of heavy metals in the surface soils studied show a lack of environmental risk for Nature Park. However, a similar distribution pattern of the investigated elements in the park and two anthropologically influenced areas in Shumen city indicated a potential hazard in Nature Park.

Open access

Rostislava Todorova-Encheva

Open access

Rositsa Davidova and Senay Sevginov

Abstract

The aim of the study is to describe the testate amoebae fauna in seven reservoirs in the Northeastern Bulgaria and to investigate the relationship of taxonomic diversity and abundance of these organisms to the some characteristics of the reservoirs. A total of 52 species, varieties and forms belonging to 15 genera were identified in the benthal of the coastal zone. There are significant differences in species richness and abundance between the testacea of different reservoirs. Number of taxa was significantly higher in the Beli Lom (29 species and 12 genera) and Loznitsa (22 species and 13 genera). Most of the reservoirs - Kara Michal, Bogdantsi, Isperih, Lipnik and Brestovene have extremely poor fauna compared to other similar reservoirs. This is confirmed by the low values of the Shannon-Weaver diversity index, which varied between 1.04 and 2.396, as well as by the other indices used to assess the environmental conditions in the reservoirs. The data of the regression analysis showed that a relation between age, surface area and water volume of the reservoirs and the species richness and abundance of testacea is not established.

Open access

Teodora Koynova

Abstract

The green areas play a significant role in keeping the urban population healthy. Consequently, there has been a growing interest in the urban and peri-urban parks lately. The Nature Park Shumen plateau and Shumen City Park are an important green area for residents of Shumen city. The aim of this study was to make comparative analysis of the qualities of the Nature Park Shumen Plateau and the Shumen City Park as green spaces.

For quality assessment 10 criteria were used. The criteria were grouped in four categories - Green space placement, Green space use, Environment and Biodiversity. Five-point Likert scale was used to determine satisfaction with each of the 10 criteria. Nine experts did the evaluation of the criteria.

In category “Green space placement”, the Nature Park Shumen Plateau and the Shumen City Park had very similar evaluations however there were big differences in the individual criteria. According to the category “Green space use, both parks showed rather similar results. Concerning the category „Environment”, the Nature Park Shumen Plateau received slightly higher assessment and the category “Biodiversity” was ranked as twice higher.

The results show that the Nature Park Shumen Plateau and the Shumen City Park possess good quality as a green area, as the Nature Park Shumen Plateau was higher assessed compared to the Shumen City Park.

Open access

M. N. Moskovkina and I. P. Bangov

Abstract

The Quantitative Structure Retention Relationship (QSRR) approach has been applied to model the gas chromatographic retention of 16 alkyloxazoles and 16 alkylthiazoles on three capillary columns with different polarities. The potential of the Charge-related Topological Index (CTI) developed by one of the authors (I.B.) was investigated as a descriptor in QSRR linear multivariate regressions. Calculated values of atomic charges and the indication of the presence of substitutions in different positions in the solute structures are used to generate regressions. Analysis of the equations derived proves their ability to describe and evaluate the participants in the chromatographic separation process. The present quantitative characterization of the chromatographic retention of alkylazoles shows the potentials of deriving QSRR models to exhibit the retention intermolecular interactions.

Open access

Ouroud Fellah, Samir Hameurlaine, Noureddine Gherraf, Amar Zellagui, Tahar Ali, Abdennabi Abidi, Muhammed Altun, Ibrahim Demirtas and Ayse SahinYaglioglu

Abstract

The aerial parts of T. gallica collected from three different locations (arid, humid and semi-arid) were extracted using ethyl acetate. The crude extracts were subjected to phenolic appraisal and antiproliferative activity using ELISA and xCELLigence assays. The total phenolic and flavonoids were evaluated using appropriate techniques to give a yield of total phenolics ranging between 238.46 and 348.56 mg GAE (Gallic acid equivalent)/g dry weight extract. The flavonoids yield was found to vary from 36.6 to 103.14 mg QE (quercetin equivalent)/g dry weight extract. Moreover, the extracts were tested against rat brain tumor (C6) and human cervix carcinoma (HeLa) cell lines and displayed important differences in activity. These disparities highlighted the effect of climatic factors as quality determinants of secondary metabolites and therefore as a key control of the biological therapeutic effect.