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A gram-negative bacterium which was capable of oxidizing reduced inorganic sulfur compounds was isolated from agricultural soil and designated BI-42. This new isolate grew on a wide range of organic substrates but was not able to grow autotrophically and lacked ribulose 1,s-bisphosphate carboxylase, a key enzyme of carbon dioxide fixation. These results suggested that strain BI-42 was a chemolithoheterotroph. Ammonia and nitrate were not used as sole nitrogen sources for growth, and strain BI-42 lacked glutamate synthase activity, which resulted in glutamate auxotrophy. The glutamate dehydrogenase activity of this organism was apparently insufficient for ammonia assimilation. On the basis of the results of additional biochemical tests, the G+C content of the DNA, the results of a respiratory ubiquinone analysis, the results of a 16s ribosomal DNA sequence analysis, the fatty acid composition, and the results of a membrane lipid analysis, strain BI-42 was identified as a phylogenetically and physiologically distinct taxon belonging to the alpha subclass of the Proteobucteria. Boseu thiooxiduns gen. nov., sp. nov. is the name proposed for this taxon.Sulfate is the end product of oxidations of reduced sulfur compounds by chemosynthetic, photosynthetic, and various heterotrophic microorganisms. Nature balances these oxidations through the biological reduction of sulfate to sulfide. Microorganisms utilize sulfur compounds for the biosynthesis of cellular material or transform these compounds as part of a respiratory energy-generating process. Most of the known sulfur-oxidizing bacteria belong to the genera Thiobacillus, Thiothrix, Beggiatoa, Thiomicrospira, Achromatium, DesuEfovibrio, Desulfomonas, Desulfococcus, and Desulfuromonas (18,55). Members of the genus Thiobacillus have been studied extensively to increase our understanding of the coupling of oxidation of reduced inorganic sulfur compounds to energy biosynthesis and assimilation of carbon dioxide (45). In addition, some phototrophic bacteria, such as members of the genus Chromatium, oxidize reduced inorganic sulfur compounds to provide reducing power for carbon dioxide assimilation during anaerobic photosynthesis (38).However, oxidation of sulfur compounds is not restricted to the true sulfur bacteria; this process also occurs in heterotrophic bacteria isolated from soil (54) and the marine environment (50, 51). Most of the heterotrophic bacteria that have such activities belong to the genera Pseudomonas (35), Mycobacterium, Arthrobacter, Flavobacterium (54), and Xanthobacter or are Escherichia coli strains (42). However, few of these heterotrophs have the ability to generate biologically useful energy from the oxidation of reduced sulfur compounds (31). An exception is Paracoccus denitrificans (6), which also grows autotrophically in the presence of thiosulfate. Only a few heterotrophic bacteria, such as Thiobacillus sp. strain Q (8) and Catenococcus thiocyclus (39), have been shown to obtain energy from the oxidation of sulfur compounds. This type of nutr...

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There is a growing interest on dynamic and broader concepts of deprivation such as vulnerability, which takes in to account the destitution of individuals from future shocks. We use the framework of decision making under uncertainty to arrive at a new measure of vulnerability to poverty. We highlight the importance of current standard of living to better capture the notion of vulnerability. In conceptualizing the new class of measures of vulnerability we thus move beyond the standard expected poverty measures that is commonly found in the literature. We also axiomatically characterize the new class of measure and discuss some of it's properties. April, 2010.We are highly indebted to Tony Shorrocks for introducing us to this topic and for his constant encouragement and generous support. We are grateful to Sabina Alkire, Joydeep Dutta, Sashi Nandiebam, Prasanta Pattanaik, Horst Zank and conference and seminar participants at the University of Bath, University of Manchester, UC Riverside, OPHI, Oxford and WIDER, Helsinki and RES, Surrey for their comments. We are also grateful to an anonymous referee whose comments have signi…cantly improved the paper.

The resistance of Alloy 22 (UNS N06022) to crevice corrosion in aggressive environments was studied using various modifi cations of the Tsujikawa-Hisamatsu Electrochemical (THE) technique. THE technique on a creviced specimen involves potentiodynamic polarization to initiate crevice corrosion, holding the specimen at constant current for a period to grow the crevice and then stepping the potential downward until the crevice repassivates. In this work, a new criterion for determining the crevice repassivation potential (E R,CREV ) is proposed, i.e., the potential at which the current reaches the passive current measured on the forward scan. This value of E R,CREV is unambiguous, conservative, and more reproducible for Alloy 22 in the solutions studied. Furthermore, this defi nition allows for a modifi cation of the THE technique that simplifi es the measurement and decreases the time of experiment. With this defi nition, it is possible to use a potentiodynamic-galvanostatic-potentiodynamic approach, which results in similar values of E R,CREV for non-welded and as-welded Alloy 22 specimens in chloride solution. Moreover, E R,CREV was independent of hold current density in the crevice region. THE technique was further modifi ed to allow determination of the crevice repassivation temperature (T R,CREV ). T R,CREV values for non-welded and as-welded Alloy 22 specimens were within 5°C. Effects of potentially inhibitive oxyanions in chloride solutions were also evaluated for Alloy 22.

The effects of Cr, Mo, and W on the crevice corrosion of a number of commercial Ni-Cr-Mo(W) alloys in 1.0 mol/L sodium chloride (NaCl) were studied using the potentiodynamicgalvanostatic-potentiodynamic technique to measure film breakdown and repassivation potentials as well as protection temperatures. As expected, Cr is the key element determining resistance to crevice initiation, but a substantial Mo alloy content is required to achieve maximum film stability, especially at temperatures >60°C. Mo, not Cr, is the major element controlling crevice propagation and repassivation. If the protection temperature is accepted as the key indicator of overall alloy resistance, then the resistance increases in the order: Alloy 625 (UNS N06625) < C-4 (UNS N06455) < C-276 (UNS N10276) < C-22 (UNS N06022) ~ Alloy 59 (UNS N06059) ~ C-2000 (UNS N06200) < Alloy 686 (UNS N06686). More generally, this order could be written: high Cr-low Mo < low Cr-high Mo < high Cr-high Mo < high Cr-high (Mo+W). The individual influences of Mo and W appear to be inseparable and, while adding W improved the resistance, adding the equivalent amount of Mo could achieve the same improvement.

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