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http://www.scielo.br/ ; Copper is an essential metal for normal plant growth and development, although is also potentially toxic. Copper participates in numerous physiological processes and is essential cofactor for many metalloproteins, however, problems arise when excess copper is present in cells. Excess copper inhibits plant growth and impairs important cellular processes (i.e., photosynthetic electron transport). Since copper is both an essential cofactor and a toxic element, different strategies with a complex network of metal trafficking pathways have been evolved in plants to appropriately regulate its homeostasis as a function of changing environmental copper level. Such strategies must prevent accumulation of the metal in the freely reactive form (metal detoxification pathways) and to ensure proper delivery of this element to target metalloproteins. The mechanisms involved in the acquisition of this essential micronutrient have not been clearly defined although a number of genes have been recently identified which encode potential copper transporters. This review gives a briefly overview of the current understanding of main features concerning copper toxicity and tolerance in plants as well as information of recent findings on copper trafficking including copper detoxification factors, copper transporters and copper chaperones. ; This work was supported by the Aragón Government (Grant P015/2001) and GC DGA 2002 program of the Gobierno de Aragón. ; Peer reviewed

This entry focuses on the Copper Inuit around the time of 1915, which is prior to extensive contact with outsiders. "The people of the Canadian Arctic most often referred to as Copper Inuit had no name for themselves as a total group, but rather referred only to local groups" (Damas, 1996). The Copper Inuit, at the time this entry focuses on, were nomadic and inhabited the coastal regions of the Coronation Gulf, ranging from Victoria Island in the north and the opposite shores in the south, to the Kent Peninsula in the east and Stapylton Bay in the west. The Copper Inuit did not have official political leadership; power was fluid among these nomadic people. Their religious beliefs centered around non-human and human spirits, as well as strongly held taboos related to the separation of land and sea. Shamans were mediators between the living and supernatural, and their powers were due to control over spirits. Shamans had limited secular influence. Because the religious beliefs were tied up with many aspects and functions of the society, this entry considers the religious group to be coterminous with the society at large. ; Non UBC ; Unreviewed ; Other

Intro -- Foreword -- Preface -- References -- Acknowledgements -- About This Book -- Contents -- Abbreviations -- 1 Copper-Organic Complexes in Cultural Heritage -- References -- 2 Corroding Copper in the Laboratory -- 2.1 Proof-of-Concept Experiments -- 2.2 Synthesis of Copper-Organic Complexes -- References -- 3 Copper-Organic Complexes Synthetized Electrochemically -- 3.1 Characterization of Copper Soaps -- 3.1.1 Fourier Transform Infrared Spectroscopy (FTIR) -- 3.1.2 Raman Spectroscopy -- 3.1.3 X-ray Photoelectron Spectroscopy (XPS) -- 3.1.4 X-ray Diffraction (XRD) -- 3.1.5 Mass Spectrometry -- 3.1.6 Discussion -- 3.2 Characterization of Cu-Lactose -- 3.2.1 FTIR -- 3.2.2 Raman -- 3.2.3 XPS -- 3.2.4 XRD -- 3.2.5 Mass Spectrometry -- 3.2.6 Discussion -- 3.3 Characterization of Cu-Casein -- 3.3.1 FTIR -- 3.3.2 Raman -- 3.3.3 XPS -- 3.3.4 XRD -- 3.3.5 Mass Spectrometry -- 3.3.6 Discussion -- References -- 4 Characterization of "Cu-Milk Corrosion" -- 4.1 Fourier Transform Infrared Spectroscopy (FTIR) -- 4.2 Raman Spectroscopy -- 4.3 X-ray Photoelectron Spectroscopy (XPS) -- 4.4 Mass Spectrometry -- 4.4.1 Gas Chromatography with Quadrupole Time-of-Flight Mass Spectrometry using a Thermal Separation Probe (GC-QTOF-MS with TSP) -- 4.4.2 Solvent Extract Derivatized with N, O-Bistrifluoroacetamide (BSTFA) Analysed by Gas Chromatography with Mass Spectrometry (GC-MS) -- 4.4.3 Proteomics -- 4.5 Discussion -- References -- 5 Conclusion -- 6 Analytical Techniques -- 6.1 Fourier Transform Infrared Spectroscopy (FTIR) -- 6.2 Raman Spectroscopy -- 6.3 X-Ray Photoelectron Spectroscopy (XPS) -- 6.4 X-Ray Diffraction (XRD) -- 6.5 Mass Spectrometry Techniques -- 6.5.1 Direct Flow Injection Analysis (FIA) -- 6.5.2 Gas Chromatography with Quadrupole Time-of-Flight Mass Spectrometry using a Thermal Separation Probe (GC-QTOF-MS with TSP) -- 6.5.3 Proteomics.

Abstract
Inhalation exposure to copper and its inorganic compounds can occur in various industrial sectors such as ore mining, production of electrical equipment etc. Toxic effects of copper and its oxides have been shown to be attributed to i. particle size and ii. dissolution/release of copper ions. The latter being dependend on the chemical composition of the copper particle and its size. Hence, in the context of occupational inhalation exposure to those compounds emphasis should not only be directed towards particle size but also to the copper species. We have developed an ICP-MS based method that allows quantitative distinction between copper oxides (CuxO) and metallic copper (mCu) upon sampling on mixed-cellulose ester (MCE) membrane filters. This approach is based on the different dissolution properties of CuxO and mCu in dilute acid. Systematic assessment of the approach in regard to filter load and extraction time have been conducted and successfully applied to field samples.