113 research outputs found
Geophagic clays: Their mineralogy, chemistry and possible human health effects
Randomly chosen representative geophagic clay samples from Cameroon and Nigeria were mineralogically and chemically analysed. The primary objectives of the study were to qualitatively and quantitatively identify the mineral constituents and to determine selected elemental compositions in the clay samples in order to infer on possible human health effects. Laboratory tests performed on the samples included X-ray powder diffractometry (XRPD), Fourier transform infra red (FTIR) spectrophotometry, and selected trace elemental analysis using inductively coupled plasma-mass spectrometer (ICP-MS). Quartz and kaolinite were conspicuously dominant in the samples. Very significantly, low concentrations of Rb, Ba, Sr, Sc, V, Cr, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo as well as Th and Pb were detected in the samples. Results depict purified and refined clays of sedimentary origin with medicinal and nutritional values beneficial to the geophagic individual though there are possibilities of associated human health risks.Key words: Kaolinite, quartz, medicinal and nutritional values, health risks
The role of the laity In The Roman Catholic Church. The âSambaâ group as an ecample of the laity carrying out diakonia In The Catholic Diocese Of Kumbo In Cameroon
The study sets out to investigate the role and self-understanding of the laity in the church using the example of âSambaâ group in the Catholic Diocese of Kumbo in the North West Region of Cameroon. In other words the work seeks to know how the Samba members understand themselves and their role as the laity which visible in the diaconal work they do in this particular diocese. In order to deal with this investigation properly, two theories have been selected to uncover the facts. These theories present the role of the laity in the church as clearly spelt out in the churchâs official documents or official Catholic teachings. The second theory to help uncover the facts deals with how the laity here represented by Samba contribute to the churchâs diakonia in a practical way, bearing in mind the common deacon hood common to all the faithful
Titanium-induced synthesis of benzofurans
Ketoesters derived from the acylation of o-hydroxyacetophenone with aliphatic as well as aromatic acid chlorides undergo intramolecular cyclization in the presence of low-valent titanium to afford benzofurans in good yields. The reduction of titanium trichloride with dry zinc powder in refluxing THF takes place in the presence of the ketoester which simultaneously cyclizes as the titanium catalyst is formed, rendering the pre-reduction of titanium trichloride in a separate step unnecessary.KEY WORDS: Ketoesters, Low-valent titanium, Benzofurans Bull. Chem. Soc. Ethiop. 2011, 25(1), 157-160
Synthesis of Coumarins and Quinolones by Intramolecular Aldol Condensation Reactions of Titanium Enediolates
Low-valent titanium prepared by the reduction of TiCl3 with zinc dust oxidatively adds to α-ketoamides or α-ketoesters with the formation of the corresponding titanium enediolates. These 1,2-difunctional nucleophiles, which have hardly been used in organic synthesis so far, undergo regioselective intramolecular aldol condensation reactions with various electrophiles such as aldehydes, ketones, nitriles, esters and amides. This methodology allows the synthesis of differently substituted coumarin and 2-quinolone derivatives
Microwave Irradiation versus Conventional Heating in the Synthesis of N-Methyl-2-pyrrolidone Catalyzed by Highly Active Copper Powder
A convenient one-pot synthesis of N-methyl-2-pyrrolidone is achieved either by conventional heating or microwave irradiation. The intermediate N-methyl-4-hydroxybutyramide formedfromthe exothermic reaction of γ-butyrolactone with aqueous methylamine undergoes an intramolecular condensation reaction catalyzed by highly active copper powder to formthe pyrrolidone in good yield.Keywords: Copper catalyst, N-methyl-2-pyrrolidone, methylamine, γ-butyrolactone, one-pot synthesis, microwave irradiatio
Synthesis of azido derivatives of mucobromic acid
Mucobromic acid is a highly reactive multicentered molecule. It was converted to its corresponding but unstable diazido derivative by reaction with two equivalents of sodium azide. The resultant 3,4-diazido-5-hydroxyfuran-2(5H)-one was obtained in moderate yield (42%) but decomposed readily even at low temperatures. Its more stable analogue 3,4-diazido-5-methoxyfuran-2(5H)-one was obtained in excellent yield after reacting 5-methoxy-3,4-dibromofuranone with two equivalents of sodium azide. The 4,5-dibromopyridazinones which are in effect masked mucobromic acid derivatives, underwent nucleophilic substitution reactions with various nucleophiles, including azides and afforded corresponding azidopyridazinones in good yields. The synthesized azido-furanone and pyridazinone derivatives are earmarked for click reactions. KEY WORDS: 3,4-Diazido-5-hydroxyfuran-2(5H)-one, 3,4-diazido-5-methoxyfuran-2(5H)-one, 4,5-Diazidopyridazinones, Mucobromic acid Bull. Chem. Soc. Ethiop. 2013, 27(1), 151-154.DOI: http://dx.doi.org/10.4314/bcse.v27i1.1
âWe are family!â The kinship between individual cosponsor and sponsored refugee(s) and its impact on mental health service uptake
Resettled refugees underutilize mental health services, despite being the immigrant population with the highest incidence of mental health issues. In Canada, individual cosponsors, particularly family members of refugees, play a crucial role in providing social support and fostering a sense of belonging during the resettlement period. These have proven effective in promoting the mental health and overall well-being of refugees. The primary objective of this research is to investigate whether the kinship (family dynamics) between individual cosponsors and refugees influences the refugeesâ willingness to access mental health services when needed.
Purposive sampling was used to select nine participants. The semi-structure interviews conducted explored the participantsâ experiences with mental health issues during the sponsorship process. Five individual cosponsors (CS) and four group sponsor representatives (CG) were interviewed. Inductive thematic analysis was used to code and analyze the data. Sixteen sponsorship experiences were discussed during the interviews. CGs identified social support and relationship building as factors influencing refugeesâ access to mental health services. In contrast, CSs emphasised the role of reducing stigma associated with mental health in facilitating refugeesâ access to such services.
The results suggest that, despite the presence of social support, sense of belonging, and family dynamics inherent in the kinship between CS and refugee, the stigma surrounding mental health remains a significant determinant of refugee access to services. It is important to note that most participants based their responses on hypothetical scenarios rather than actual experiences, as only two out of the sixteen sponsorships mentioned involved mental health issues
Low-Valent Titanium Induced Carbonyl Coupling Reactions
Interest in the use of low-valent titanium species as reagents in organic synthesis began with Van Tamelen and his research team in 1965, when they reported the first ever low-valent titanium-induced reductive dimerization of alcohols to give hydrocarbons [1]. In the early seventies shortly after the Van Tamelen report, the research teams of Mukaiyama,[2] Tyrlik[3] and McMurry[4] made the independent and simultaneous discovery that ketones and aldehydes undergo reductive dimerization to yield olefins on treatment with low-valent titanium reagents. Particularly McMurry and his co-workers [5,6,7] have extensively investigated this reaction, therefore this process is now generally referred to as the âMcMurry reactionâ
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