Metal complexes of salicylhydroxamic acid and 1,10-phen-anthroline; equilibrium and antimicrobial activity studies

Salicylhydroxamic acid and its binary and ternary copper(II), nickel(II), and iron(III) complexes involving 1,10-phenanthroline were studied pH-potentiometrically in 0.15 mol.L-1 NaNO3 aqueous solutions at 37 oC. The protonation constants of salicylhydroxamic acid and 1,10-phenanthroline as well their binary and mixed ligand complex species stability constants were determined based on 3 estimation models (Irving Rossetti, Bjerrum-Calvin and Hyperquad 2008). Also, six solid complexes were synthesized and their biological activities were evaluated against some pathogenic bacteria and fungi organisms. KEY WORDS: Salicylhydroxamic acid, 1,10-Phenanthroline, Potentiometry, Antifungal and antibacterial activities Bull. Chem. Soc. Ethiop. 2014, 28(3), 393-402.DOI: http://dx.doi.org/10.4314/bcse.v28i3.

Analysis of Employee Engagement in PT kartina Trisatria

Abstract. PT. Kartina Trisatria is a nationwide company centered in Tanah Abang (the head office recently moved to Tanah Kusir, Jakarta) that has 83 direct employees and also has business partners (for production) with more than 1000 employees and also had implemented the employee engagement strategy, which is a concept that became very important human resource management strategy in companies worldwide, for their daily business activity. But even with the implementation of employee engagement, the employee turnover of PT Kartina Trisatria is still quiet high averaging 11.735% in 2009-2013 (PT. Kartina Trisatria, 2014). The purpose of this research is to find out which factor that affect the employee engagement in PT Kartina Trisatria and in the end will analyze about factors that need more improvements, in order to maintain the employee engagement within employees in the company. The employee engagement model this research will use is based on the American Society for Training and Development (ASTD) because it is suitable with the internal condition of the company to identify which driver variables of employee engagement needed to be improved. This research primary data was taken from questionnaire and interview with the employees in PT Kartina Trisatria. Then the questionnaire data was analyzed using the frequency test method with SPSS software. The interview was explained using narrative in the project. The analysis of the data showed this research that the driver variable that has the lowest score was the hygiene factor, which consists of resources and job salary given by the company. These researches gave suggestions about the improvement of the compensation system and also add some variables, which is position allowance, vehicle allowance, merit pay, and family allowance. Keywords: employee engagement, PT Kartina Trisatria, ASTD, compensation, Herzber

Analysis of Employee Engagement in PT kartina Trisatria

Abstract. PT. Kartina Trisatria is a nationwide company centered in Tanah Abang (the head office recently moved to Tanah Kusir, Jakarta) that has 83 direct employees and also has business partners (for production) with more than 1000 employees and also had implemented the employee engagement strategy, which is a concept that became very important human resource management strategy in companies worldwide, for their daily business activity. But even with the implementation of employee engagement, the employee turnover of PT Kartina Trisatria is still quiet high averaging 11.735% in 2009-2013 (PT. Kartina Trisatria, 2014). The purpose of this research is to find out which factor that affect the employee engagement in PT Kartina Trisatria and in the end will analyze about factors that need more improvements, in order to maintain the employee engagement within employees in the company. The employee engagement model this research will use is based on the American Society for Training and Development (ASTD) because it is suitable with the internal condition of the company to identify which driver variables of employee engagement needed to be improved. This research primary data was taken from questionnaire and interview with the employees in PT Kartina Trisatria. Then the questionnaire data was analyzed using the frequency test method with SPSS software. The interview was explained using narrative in the project. The analysis of the data showed this research that the driver variable that has the lowest score was the hygiene factor, which consists of resources and job salary given by the company. These researches gave suggestions about the improvement of the compensation system and also add some variables, which is position allowance, vehicle allowance, merit pay, and family allowance. Keywords: employee engagement, PT Kartina Trisatria, ASTD, compensation, Herzber

Fuzzy quality function deployment for aircraft maintenance organizations

In this thesis, Quality Function Deployment for aircraft maintenance organizations is considered. Assessment and evaluation of quality management in aircraft maintenance organizations is the key to ensure safety, reliability, and the assurance of quality. At present, companies around the world have an absolute need for quality management systems in order to help them to develop and manage better their activities. Improving the way in which organizations handle their organizational management plays a major role in raising the standard of the quality of the product or the quality of the service they deliver. The challenge of implementing quality approaches in the management of aircraft maintenance organizations is appealing since it is recognized to save time and money. As a result, the organization can become more efficient, more competitive in its domain and finally more profitable. Quality management is, therefore, an essential function for maintaining and improving the quality of the services and products provided by aircraft maintenance organizations. First necessary background and theoretical knowledge on aircraft maintenance organizations and quality management is presented in detail. This is achieved by performing an analysis of the needs and the means for improving quality in the maintenance activities. The proposed analysis approach is a combination of Quality Function Deployment, and Fuzzy Logic theory. The Quality Function Deployment is used as an analysis tool to translate the customer needs and requirements into service features. The Quality Function Deployment involves the construction of a matrix structure which allows the assessment and ranking of different course of action with respect to quality. Since many opinions from experts are expressed in linguistic terms it appeared that fuzzy logic could improve this analysis process. Then, the final part of the thesis is devoted to the development of a fuzzy quality function deployment. The proposed analysis approach is then illustrated in the case of aircraft maintenance organizations where the objective is to increase fleet availability, maintain aircraft reliability, decrease servicing time, and limit investment costs.--------------------------------------------------------------------------------------------------------Dans cette thèse, le déploiement de la fonction de la qualité pour l'organisation de l'entretien des avions est considérée. L'évaluation de la gestion de la qualité dans les organismes de maintenance des avions est la clé pour garantir la sécurité, la fiabilité et l'assurance de la qualité. De nos jours, les entreprises partout dans le monde ont un besoin absolu de systèmes, gestion de la qualité afin de les aider à développer et à mieux gérer leurs activités. La façon dont les organisations gèrent leurs gestions de l'organisation joue un rôle majeur dans l'amélioration du niveau de la qualité du produit ou la qualité du service qu'elles fournissent. Le défi de la mise en œuvre de la démarche qualité dans la gestion de la maintenance des avions est important car il doit conduire à des économies de temps et d'argent. La gestion de la qualité est, par conséquent, une fonction essentielle pour maintenir et améliorer la qualité des services et produits offerts par les organismes de maintenance des avions. Dans cette thèse les prés requis et connaissances théoriques sur l'organisation de la maintenance et la gestion de la qualité sont présentés en détail. Ceci est réalisé en effectuant une analyse des besoins et des moyens pour améliorer la qualité dans les activités d'entretien. L'approche d'analyse proposée est une combinaison du déploiement de la fonction de la qualité et de la Logique Floue. Le déploiement de la fonction de la qualité est utilisé comme un outil d'analyse pour traduire les besoins des clients et les besoins en qualité des services. Le déploiement de la fonction de la qualité comprend la construction d'une structure matricielle permettant d’évaluer et de comparer les différents plans d’action. Puisque de nombreuses opinions d'experts sont exprimées en termes linguistiques, il semble que la Logique Floue pourrait améliorer ce processus d'analyse. La dernière partie de cette thèse est consacrée à l'élaboration du déploiement de la fonction de la qualité dans le cadre de la Logique Floue. L'approche d'analyse proposée est ensuite illustrée dans le cas de l'organisation de l'entretien d’une flotte d’avions. L'objectif est d'augmenter la disponibilité de la flotte, de maintenir sa fiabilité, de diminuer le temps du service de maintenance, de limiter les coûts d'investissemen

Nicotine metal complexes: synthesis, characterization and bioactivities of some main group and some transition metals

A number of some main group and transition metal nicotine complexes were synthesized and fully characterized using detailed structural and spectroscopic analysis techniques such as elemental analysis, molar conductivities, magnetic susceptibilities, IR, Raman and NMR techniques. Moreover, scanning electron micrographs and thermogravimetric analyses were also done. Cytotoxic activities of the binary nicotine metal complexes were tested and evaluated against HepG2 (human hepatocellular carcinoma), HPC3 (human prostate cancer), and HCT116 (human colorectal carcinoma) tumor cell lines. The antioxidant activities were examined by free radical scavenging assay. The antimicrobial activities of the synthesized complexes were evaluated against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) microbes. The relationship between the chemical structure of the synthesized complexes and their biological influence as antimicrobial drugs was studied and evaluated.                     KEY WORDS: Nicotine metal complexes, Cytotoxicity, Antioxidant, Antimicrobial   Bull. Chem. Soc. Ethiop. 2020, 34(3), 501-521. DOI: https://dx.doi.org/10.4314/bcse.v34i3.

Raman spectra of copper, cobalt, and nickel complexes of nicotinic acid: Equilibrium studies

This article summarizes the protonation and complexation equilibrium constants of nicotinic acid (NA) using different analytical techniques and software’s. Additionally, Raman, IR, and NMR spectra were done for nicotinic acid ligand and for its solid complexes with copper(II), cobalt(II) and nickel(II) metal ions.               KEY WORDS: Nicotinic acid, Potentiometry, Spectrometry, Equilibrium constants Bull. Chem. Soc. Ethiop. 2018, 32(3), 459-467.DOI: https://dx.doi.org/10.4314/bcse.v32i3.

In vitro evaluation of electroporated gold nanoparticles and extremely-low frequency electromagnetic field anticancer activity against Hep-2 laryngeal cancer cells

Introduction. The extremely-low frequency electromagnetic field (ELFEMF) has been proposed for use in cancer therapy since it was found that magnetic waves interfere with many biological processes. Gold nanoparticles (Au-NPs) have been widely used for drug delivery during cancer in vitro studies due to their low cytotoxity and high biocompatibility. The electroporation of cancer cells in a presence of Au-NPs (EP Au-NPs) can induce cell apoptosis, alterations of cell cycle profile and morphological changes. The impact of ELFEMF and EP Au-NPs on morphology, cell cycle and activation of apoptosis-associated genes on Hep-2 laryngeal cancer cell line has not been studied yet. Materials and methods. ELFEMF on Hep-2 cells were carried out using four different conditions: 25/50 mT at 15/30 min, while Au-NPs were used as direct contact (DC) or with electroporation (EP, 10 pulses at 200V, equal time intervals of 4 sec). MTT assay was used to check the toxicity of DC Au-NPs. Expression of CASP3, P53, BAX and BCL2 genes was quantified using qPCR. Cell cycle was analyzed by flow cytometry. Hematoxylin and eosin (HE) staining was used to observe cell morphology. Results. Calculated IC50 of DC Au-NPs 24.36 μM (4.79 μg/ml) and such concentration was used for further DC and EP AuNPs experiments. The up-regulation of pro-apoptotic genes (CASP3, P53, BAX) and decreased expression of BCL2, respectively, was observed for all analyzed conditions with the highest differences for EP AuNPs and ELFEMF 50 mT/30 min in comparison to control cells. The highest content of cells arrested in G2/M phase was observed in ELFEMF-treated cells for 30 min both at 25 or 50 mT, while the cells treated with EP AuNPs or ELFEMF 50 mT/15 min showed highest ratios of apoptotic cells. HE staining of electroporated cells and cells exposed to ELFEMF’s low and higher frequencies for different times showed nuclear pleomorphic cells. Numerous apoptotic bodies were observed in the irregular cell membrane of neoplastic and necrotic cells with mixed euchromatin and heterochromatin. Conclusions. Our observations indicate that treatment of Hep-2 laryngeal cancer cells with ELFEMF for 30 min at 25–50 mT and EP Au-NPs can cause cell damage inducing apoptosis and cell cycle arrest

Bioactivities of holmium(III) and gadolinium(III) complexes of thymoquinone

Chemotherapeutic agents which are the main stay in cancer treatment are toxic with numerous contrary side effects. A number of chemical, physical, and computational techniques were applied to synthesize and elucidate the structural and functional characterization of the new designed bioligands and their metal complexes. Besides, several biological techniques for developing therapeutics and diagnostics agents of these new designed materials were used. The trivalent holmium(III) and gadolinium(III) metal complexes of thymoquinone (TQ) were synthesized. Toxicities and other bioactivites were undertaken with existing drug combinations and more effective tumor models will be established. The molecular structures of TQ-metal complexes were elucidated based on particular spectral approaches. The NF-kB (nuclear factor kappa-light-chain enhancer of activated B Cells) luciferase, elastase release, superoxide anion (O2•−) generation, and DPPH (1,1-diphenyl-2-picryl hydrazyl) free-radical scavenging activities of TQ and its synthesized complexes were elucidated and discussed. The core research is to use coordination and organometallic chemistry to design new bioligands and binary, ternary, mixed ligand, multi metal multi ligand complexes pursing a bio target continuously with structure-activity relationships (SARS).                     KEY WORDS: Thymoquinone, Holmium, Gadolinium, Bioactivities   Bull. Chem. Soc. Ethiop. 2021, 35(1), 87-96. DOI: https://dx.doi.org/10.4314/bcse.v35i1.

Evaluation of the efficacy of two new biotechnological-based freeze-dried fertilizers for sustainable fe deficiency correction of soybean plants grown in calcareous soils

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpls.2019.01335/ full#supplementary-materialCurrently, fertilization with synthetic chelates is the most effective agricultural practice to prevent iron (Fe) deficiencies in crops, especially in calcareous soils. Because these compounds are not biodegradable, they are persistent in the environment, and so, there is the risk of metal leaching from the soils. Thus, new, more environment-friendly efficient solutions are needed to solve iron-deficiency-induced chlorosis (IDIC) in crops grown in calcareous soils. Therefore, the central aim of this work was to prepare new freeze-dried Fe products, using a biotechnological-based process, from two siderophores bacterial (Azotobacter vinelandii and Bacillus subtilis) cultures (which previously evidenced high Fe complexation ability at pH 9) and test their capacity for amending IDIC of soybean grown in calcareous soils. Results have shown that A. vinelandii iron fertilizer was more stable and interacted less with calcareous soils and its components than B. subtilis one. This behavior was noticeable in pot experiments where chlorotic soybean plants were treated with both fertilizer products. Plants treated with A. vinelandii fertilizer responded more significantly than those treated with B. subtilis one, when evaluated by their growth (20% more dry mass than negative control) and chlorophyll development (30% higher chlorophyll index than negative control) and in most parameters similar to the positive control, ethylenediamine-di(o-hydroxyphenylacetic acid). On average, Fe content was also higher in A. vinelandii-treated plants than on B. subtilis-treated ones. Results suggest that this new siderophore-based formulation product, prepared from A. vinelandii culture, can be regarded as a possible viable alternative for replacing the current nongreen Fe-chelating fertilizers and may envisage a sustainable and environment-friendly mending IDIC of soybean plants grown in calcareous soils.This work was financially supported by Project PTDC-AGRTEC-0458-2014 - POCI-01-0145-FEDER-016681 - funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES and Project RTI2018096268-B-I00 by the State Research Agency, Ministry of Science, Innovation and Universities of Spain.info:eu-repo/semantics/publishedVersio

Evaluation of the efficacy of two new biotechnological-based freeze-dried fertilizers for sustainable fe deficiency correction of soybean plants grown in calcareous soils

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpls.2019.01335/ full#supplementary-materialCurrently, fertilization with synthetic chelates is the most effective agricultural practice to prevent iron (Fe) deficiencies in crops, especially in calcareous soils. Because these compounds are not biodegradable, they are persistent in the environment, and so, there is the risk of metal leaching from the soils. Thus, new, more environment-friendly efficient solutions are needed to solve iron-deficiency-induced chlorosis (IDIC) in crops grown in calcareous soils. Therefore, the central aim of this work was to prepare new freeze-dried Fe products, using a biotechnological-based process, from two siderophores bacterial (Azotobacter vinelandii and Bacillus subtilis) cultures (which previously evidenced high Fe complexation ability at pH 9) and test their capacity for amending IDIC of soybean grown in calcareous soils. Results have shown that A. vinelandii iron fertilizer was more stable and interacted less with calcareous soils and its components than B. subtilis one. This behavior was noticeable in pot experiments where chlorotic soybean plants were treated with both fertilizer products. Plants treated with A. vinelandii fertilizer responded more significantly than those treated with B. subtilis one, when evaluated by their growth (20% more dry mass than negative control) and chlorophyll development (30% higher chlorophyll index than negative control) and in most parameters similar to the positive control, ethylenediamine-di(o-hydroxyphenylacetic acid). On average, Fe content was also higher in A. vinelandii-treated plants than on B. subtilis-treated ones. Results suggest that this new siderophore-based formulation product, prepared from A. vinelandii culture, can be regarded as a possible viable alternative for replacing the current nongreen Fe-chelating fertilizers and may envisage a sustainable and environment-friendly mending IDIC of soybean plants grown in calcareous soils.This work was financially supported by Project PTDC-AGRTEC-0458-2014 - POCI-01-0145-FEDER-016681 - funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES and Project RTI2018096268-B-I00 by the State Research Agency, Ministry of Science, Innovation and Universities of Spain.info:eu-repo/semantics/publishedVersio