Synthesis and evaluation of antioxidant and antimicrobial activities of Schiff base tin (II) complexes

Purpose: To synthesize and evaluate Schiff base Tin (II) complexes for antioxidant and antimicrobial activitiesMethods: The complexes of Tin (II) chloride with various Schiff base derivative of 2-Hydroxy-1- naphthaldehyde (HN) were synthesized and characterized by various physiochemical techniques, including elemental analysis, ultraviolet–visible (UV-Vis) spectrophotometry, Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H–NMR), carbon-13 nuclear magnetic resonance (13C-NMR), electron ionization mass spectrometry (EIMS) and conductance studies. Agarwell diffusion and agar-well dilution techniques were used for antimicrobial assessment. Evaluation of the antioxidant activity of the ligands and complexes was accomplished by DPPH radical scavenging assay.Results: The results indicate coordination of deprotonated phenolic oxygen and nitrogen of azomethine with Tin (II) chloride led to the formation of stable complexes. The Tin (II) complexes showed good antimicrobial and antioxidant activities. Compounds (HNPA and [Sn(HNPA)Cl2(H2O)2) were noteworthy (p < 0.05) in this regard with antibacterial activity against Staphylococcus aureus, while [Sn(HNCA)Cl2(H2O)2 and [Sn(HNPT)Cl2(H2O)2 were active against Klebsiella pneumoniae..Conclusion: All synthesized Schiff bases and their Tin (II) complexes showed high antimicrobial and antioxidant activities than their corresponding ligands.Keywords: Schiff base, Ligand, Tin (II) complexes, Antimicrobial, Antioxidant, Deprotonated phenolic oxyge

Hyperspectral discrimination of tree species with different classifications using single- and multiple-endmember.

Discrimination of tree species with different ages is performed in three classifications using hyperspectral data. The first classification is between Broadleaves and pines; the second classification is between Broadleaves, Corsican Pines, and Scots Pines, and the third classification is between six tree species including different ages of Corsican and Scots Pines. These three classifications are performed by having single- and multiple-endmember and considering five different spectral measure techniques (SMTs) in combination with reflectance spectra (ReflS), first and second derivative spectra. The result shows that using single-endmember, derivative spectra are not useful for a more challenging classification. This is further emphasized in multiple-endmember classification, where all SMTs perform better in ReflS rather than derivative in all classifications. Furthermore, using derivative spectra, discrimination accuracy become more dependent on the type of SMTs, especially in single-endmember. By employing multiple-endmember, the within-species variation is significantly reduced, thereby, the remaining challenge in discriminating tree species with different ages is only due to the between-species similarity. Overall, discrimination accuracies around 92.4, 76.8, and 71.5% are obtained using original reflectance and multiple-endmember for the first, second, and third classification, which is around 14.3, 17, and 8.3% higher than what were obtained in single-endmember classifications, respectively. Also, amongst the five SMTs, Euclidean distance (in both single- and multiple-endmember) and Jeffreys–Matusita distance (in single-endmember and derivative spectra) provided the highest discrimination accuracies in different classifications. Furthermore, when discrimination become more challenging from the first to second and third classification, the performance difference between different SMTs is increased from 1.4 to 3.8 and 7.3%, respectively. The study shows high potential of multiple-endmember to be employed in remote sensing applications in the future for improving tree species discrimination accuracy

A Novel Therapy for Melanoma Developed in Mice: Transformation of Melanoma into Dendritic Cells with Listeria monocytogenes

Listeria monocytogenes is a gram-positive bacteria and human pathogen widely used in cancer immunotherapy because of its capacity to induce a specific cytotoxic T cell response in tumours. This bacterial pathogen strongly induces innate and specific immunity with the potential to overcome tumour induced tolerance and weak immunogenicity. Here, we propose a Listeria based vaccination for melanoma based in its tropism for these tumour cells and its ability to transform in vitro and in vivo melanoma cells into matured and activated dendritic cells with competent microbicidal and antigen processing abilities. This Listeria based vaccination using low doses of the pathogen caused melanoma regression by apoptosis as well as bacterial clearance. Vaccination efficacy is LLO dependent and implies the reduction of LLO-specific CD4+ T cell responses, strong stimulation of innate pro-inflammatory immune cells and a prevalence of LLO-specific CD8+ T cells involved in tumour regression and Listeria elimination. These results support the use of low doses of pathogenic Listeria as safe melanoma therapeutic vaccines that do not require antibiotics for bacterial removal

Ambivalence toward men: comparing sexism among Polish, South African and British university students

This study extends the literature on attitudes toward gender roles by exploring whether the nature of sexism (i.e., benevolence and hostility directed at men) differs among university students from two under-researched countries, Poland (n = 190) and South Africa (n = 188), in a comparison with students in the United Kingdom (n = 166). Based on empirical literature applying Ambivalent Sexism Theory, and in the light of the socio-political context, it was hypothesized that: (1) both hostile and benevolent attitudes toward men in Poland would be more liberal than in South Africa and more conservative than in the United Kingdom, and (2), women would exhibit more hostile but less benevolent attitudes than men in relatively more conservative South Africa. The Ambivalence to Men Inventory was used to measure the two types of sexist attitudes about men. Findings supported the first hypothesis for hostile attitudes and partially for benevolent attitudes. South African and Polish students were more benevolent and hostile to men than British students, and students from South Africa were more hostile than those from Poland. Moreover, as predicted, a significant country-by-gender interaction revealed that South African women had more hostile and less benevolent attitudes to men than South African men. No such gender gap was present in the case of hostile attitudes in Poland and benevolent attitudes in the United Kingdom. Findings are discussed in terms of Ambivalent Sexism Theory and the countries’ socio-cultural context

Divorce Trends in Seven Countries Over the Long Transition from State Socialism: 1981–2004

The collapse of communism was a defining geopolitical event of late-20th century Europe, with well-documented economic, social, and political implications. Yet there is a striking absence of research on how it influenced divorce. The objective of this study is to provide an exploratory analysis of trends in divorce over the long transition from communism—starting from the decline of the communist economy in the 1980s and ending with economic revival—in seven countries: Bulgaria, Estonia, Hungary, Lithuania, Poland, Romania, and Russia. We discuss how the transition could be expected to either increase or decrease divorce risks. We analyze retrospective micro-level data on first marriages from the Changing Life Course Regimes in Eastern Europe (CLiCR) dataset. Based on our event-history analyses, we find that divorce rates increased in each country at some stage during the long transition and these increases cannot be explained by compositional change of the marriages. However, no uniform pattern emerged in the timing and duration of the increase in divorce risk. This striking variation leads us to conclude that even the effect of major societal ruptures is contextually contingent

Design, Development and Testing an Academic Repository

Technological advances, established best web development practices, and modern design of the 21st century have provided students, professors, researchers, etc., quasi-effortless access to academic documents encompassed within cleaner user interface and a higher level of usability. Access to and rigorous management of research publication and products is also mandated by funding agencies. Given these characteristics, we have developed an academic repository to maintain the student projects in a typical academic department. A repository of this nature is comprised of two major components: the database and the user interface. The key focus is to provide secure access to research materials (e.g. Master\u27s projects and the like), similar to that of a community or university library\u27s online catalogs, while sustaining a keen eye for contemporary front-end design. In addition to providing access to documentation, this repository uses collected data to present various citation styles, assisting users with easy composition of reference pages. Through a familiar search engine paradigm, information on projects, as well as the projects themselves, are discovered and queried using keywords and will be as if performing a Google search. The repository, while focused on single academic unit, can be expended as a campus wide tool, and provides an in house, easily expandable solution to off-the shelf repository solutions