5 research outputs found

    Spectroscopic Characterization and Bioanalytical Applications of Benzophenoxazine Derivatives and the Use of Dyes and Dye-Encapsulated Silica Nanoparticles for Fingerprint Detection

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    The use of benzophenoxazine dyes such as Nile red and Nile blue in various applications has received increasing attention in recent years. Due to the limitations of using the two dyes in aqueous media because of their poor solubility, extensive efforts have been made to synthesize new benzophenoxazine analogues. Therefore, the first part of the work aims to characterize modified structures of benzophenoxazine derivatives as well as Nile red and Nile blue using spectroscopic techniques. The optical properties of the dyes involve the determination of molar absorptivity and quantum yield values as well as photostability studies. The absorbance and emission wavelengths are in the visible and near-infrared region of the electromagnetic spectrum which is the most useful region for bioanalytical applications due to the reduced autofluorescence from biomolecules. The first part also includes the interactions between benzophenoxazine derivatives and human serum albumin. The affinity of the dye to the protein is hydrophobicity-dependent, but other parameters such as steric hindrance and electrostatic interaction play a role too as confirmed by binding constant values. Detection of fingerprints is considered one of the most valuable pieces of evidence in forensic investigations. The second part of the work aims to use benzophenoxazine derivatives for fingerprint detection on porous surfaces. The factors affecting the ability of Nile red and Nile blue derivatives to develop luminescent and visible fingerprints with good background contrast are discussed. The second part also contains the application of silica nanoparticles encapsulating some benzophenoxazine derivatives as well as fluorescein isothiocyanate as fingerprint reagents. The efficiency to develop fingerprints is governed by the nature of the encapsulated dye and organosilicate precursors

    The effects of agricultural land use on the community structure and functioning of small freshwater habitats

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    Agriculture is important for maintaining human well-being, but intensive agricultural production can have adverse environmental impacts. Freshwater ecosystems are particularly vulnerable to chemical and physical stressors resulting from agricultural land use, but few studies have compared the effects of different types of agricultural practices on the ecology of small water bodies. In agricultural catchments, the two major land uses, arable and pastoral, differ in their management (e.g. ploughing, fertilizer and pesticide inputs) and therefore in their potential effect on freshwater communities. The aim of this study was to investigate the effects of two types of agricultural land use (arable and pastoral) on the community structure and functioning of ponds and streams. Twenty four sites (6 arable ponds, 6 arable streams, 6 pastoral ponds and 6 pastoral streams) were studied in Leicestershire, UK. Arable streams had lower macroinvertebrate abundance and taxonomic richness than pastoral streams and arable ponds had lower diatom species richness, diversity and evenness than pastoral ponds. Leaf litter decomposition was also higher in arable than pastoral ponds. Feeding by macroinvertebrate shredders (e.g. Gammarus pulex) was a significant contributor to leaf breakdown in streams but not in ponds. The feeding rates of G. pulex and Asellus aquaticus were significantly affected by temperature and intraspecific interactions (i.e. density). Increasing density resulted in greater per capita leaf mass loss of A. aquaticus and lower survival rate of G. pulex. At higher temperature, the per capita leaf mass loss and feeding rates for both species were greater whereas the survival rates were lower. Agricultural land use can adversely affect the structure and functioning of aquatic communities. Consequently, it may have a considerable potential impact on ecosystem services provided by freshwater habitats. Understanding the possible effects of agricultural land use on the structure and functioning of freshwater ecosystems is extremely important and should help in identifying the best land use management to maintain sustainable agricultural production and protect freshwater habitats

    Disturbance in Some Fertility Biomarkers Induced and Changes in Testis Architecture by Chronic Exposure to Various Dosages of Each of Nonylphenol or Bisphenol A and Their Mix

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    This investigation was conducted to demonstrate the potential impacts of different doses of Bisphenol A (BPA) or Nonylphenol (NP) and their mixtures on some biological activities in male albino rats. Seventy male albino rats were allocated to the control group (GI) and were given 1 mL of ethanol. G II and G III were given 100 mg/kg of each of BPA and NP, G IV and G V were given 25 mg/kg of each of BPA and NP, G VI was given a high dose of BPA and NP, and G VII was given a low dose of BPA and NP. All animals were treated orally for 60 days. Serum biomarkers of oxidative stress, antioxidants, immune-inflammatory mediators, and apoptotic markers were determined, as well as a histopathological examination of the testis at the end of the experimental period. The results obtained showed a pronounced increase in malondialdehyde (MDA), protein carbonyl (PC), and 4-hydroxynonenol (4-HNE), concomitant with a significant reduction in serum Superoxide dismutase (SOD), catalase enzyme (CAT), and total antioxidant capacity (TAC) in all treated groups. A significant elevation in TNF Alpha, TNF Beta, and Caspase 3 serum was recorded individually and in the groups treated with high doses. The disturbance is represented by histological damage in the testis in the germinal epithelium and a decrease in spermatozoa inside the lumen of seminiferous tubules. The effects on testis tissues were dose-dependent, pronounced in mixture doses, and remarkable in higher doses. In conclusion, exposure to BPA and NP strongly impacts antioxidants, immune-inflammatory mediators, and testis tissue architecture. Furthermore, the data from this investigation support the idea that exposure to BPA and NP in daily life has multiple damages

    Interpol review of fingermarks and other body impressions 2016–2019

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