Two new arsenate/sulfate-reducing bacteria: mechanisms of arsenate reduction

Two sulfate-reducing bacteria, which also reduce arsenate, were isolated; both organisms oxidized lactate incompletely to acetate. When using lactate as the electron donor, one of these organisms, Desulfomicrobium strain Ben-RB, rapidly reduced (doubling time = 8 h) 5.1 mM arsenate at the same time it reduced sulfate (9.6 mM). Sulfate reduction was not inhibited by the presence of arsenate. Arsenate could act as the terminal electron acceptor in minimal medium (doubling time = 9 h) in the absence of sulfate. Arsenate was reduced by a membrane-bound enzyme that is either a c-type cytochrome or is associated with such a cytochrome; benzyl-viologen- dependent arsenate reductase activity was greater in cells grown with arsenate/sulfate than in cells grown with sulfate only. The second organism, Desulfovibrio strain Ben-RA, also grew (doubling time = 8 h) while reducing arsenate (3.1 mM) and sulfate (8.3 mM) concomitantly. No evidence was found, however, that this organism is able to grow using arsenate as the terminal electron acceptor. Instead, it appears that arsenate reduction by the Desulfovibrio strain Ben-RA is catalyzed by an arsenate reductase that is encoded by a chromosomally-borne gene shown to be homologous to the arsC gene of the Escherichia coli plasmid, R773 ars system.

Subgroup relations: A comparison of mutual intergroup differentiation and common ingroup identity models of prejudice reduction

Two studies examined relations between groups (humanities and math-science students) that implicitly or explicitly share a common superordinate category (university student). In Experiment 1, 178 participants performed a noninteractive decision-making task during which category salience was manipulated in a 2 (superordinate category salience) x 2 (subordinate category salience) between-groups design. Consistent with the mutual intergroup differentiation model, participants for whom both categories were salient exhibited the lowest levels of bias, whereas bias was strongest when the superordinate category alone was made salient. This pattern of results was replicated in Experiment 2 (N = 135). In addition, Experiment 2 demonstrated that members of subgroups that are nested within a superordinate category are more sensitive to how the superordinate category is represented than are members of subgroups that extend beyond the boundaries of the superordinate category.

Effects of acid treatments of carbon on N2O and NO reduction by carbon-supported copper catalysts

The influences of HCl, HNO3 and HF treatments of carbon on N2O and NO reduction with 20 wt% Cu-loaded activated carbon were studied. The order of activity in both N2O and NO is as follows: Cu20/AC-HNO3>Cu20/AC>Cu20/AC-HF>Cu20/AC-HCl. The same sequence was also observed for the amount of CO2 evolved during TPD experiments of supports acid for the catalyst dispersion. On the other hand, N2O exhibited a higher reaction rate than NO and a higher sensitivity to acid treatments, and the presence of gas-phase O-2 had opposite effects in N2O and NO reduction. The key role of carbon surface chemistry is examined to rationalize these findings and the relevant mechanistic and practical implications are discussed. The effects of oxygen surface groups on the pore structure of supports and catalysts are also analyzed, (C) 2000 Elsevier Science Ltd. All rights reserved.

Level-one highest weight representations of U-q[g1(1 vertical bar 1)] and associated vertex operators

We study the level-one irreducible highest weight representations of U-q[gl(1\1)] and associated q-vertex operators. We obtain the exchange relations satisfied by these vertex operators. The characters and supercharacters associated with these irreducible representations are calculated'. (C) 2000 Published by Elsevier Science B.V. All rights reserved.

Level-one highest weight representation of U-q[sl((N)over-cap vertical bar 1)] and Bosonization of the multicomponent Super t-J model

We study the level-one irreducible highest weight representations of the quantum affine superalgebra U-q[sl((N) over cap\1)], and calculate their characters and supercharacters. We obtain bosonized q-vertex operators acting on the irreducible U-q[sl((N) over cap\1)] modules and derive the exchange relations satisfied by the vertex operators. We give the bosonization of the multicomponent super t-J model by using the bosonized vertex operators. (C) 2000 American Institute of Physics. [S0022- 2488(00)00508-9].

Placental growth hormone (GH), GH-binding protein, and insulin-like growth factor axis in normal, growth-retarded, and diabetic pregnancies: Correlations with fetal growth

We previously described significant changes in GH-binding protein (GHBP) in pathological human pregnancy. There was a substantial elevation of GHBP in cases of noninsulin-dependent diabetes mellitus and a reduction in insulin-dependent diabetes mellitus. GHBP has the potential to modulate the proportion of free placental GH (PGH) and hence the impact on the maternal GH/insulin-like growth factor I (IGF-I) axis, fetal growth, and maternal glycemic status. The present study was undertaken to investigate the relationship among glycemia, GHBP, and PGH during pregnancy and to assess the impact of GHBP on the concentration of free PGH. We have extended the analysis of specimens to include measurements of GHBP, PGH, IGF-I, IGF-II, IGF-binding protein-1 (IGFBP-1), IGFSP-2, and IGFBP-3 and have related these to maternal characteristics, fetal growth, and glycemia. The simultaneous measurement of GHBP and PGH has for the first time allowed calculation of the free component of PGH and correlation of the free component to indexes of fetal growth and other endocrine markers. PGH, free PGH, IGF-I, and IGF-II were substantially decreased in IUGR at 28-30 weeks gestation (K28) and 36-38 weeks gestation (K36). The mean concentration (+/-SEM) of total PGH increased significantly from K28 to K36 (30.0 +/- 2.2 to 50.7 +/- 6.2 ng/mL; n = 40), as did the concentration of free PGH (23.4 +/- 2.3 to 43.7 +/- 6.0 ng/mL; n = 38). The mean percentage of free PGH was significantly less in IUGR than in normal subjects (67% vs. 79%; P < 0.01). Macrosomia was associated with an increase in these parameters that did not reach statistical significance. Multiple regression analysis revealed that PGH/IGF-I and IGFBP-5 account for 40% of the variance in birth weight. IGFBP-3 showed a significant correlation with IGF-I, IGF-II, and free and total PGK at K28 and K36. Noninsulin-dependent diabetes mellitus patients had a lower mean percentage of free PGH (65%; P < 0.01), and insulin-dependent diabetics had a higher mean percentage of free PGH (87%; P < 0.01) than normal subjects. Mean postprandial glucose at K28 correlated positively with PGH and free PGH (consistent with the hyperglycemic action of GH). GHBP correlated negatively with both postprandial and fasting glucose. Although GHBP correlated negatively with PGH (r = -0.52; P

Evaluation of a new bioelectrical impedance instrument for the prediction of body cell mass independently of height or weight

The objective of the present study was to evaluate the performance of a new bioelectrical impedance instrument, the Soft Tissue Analyzer (STA), which predicts a subject's body composition. A cross-sectional population study in which the impedance of 205 healthy adult subjects was measured using the STA. Extracellular water (ECW) volume (as a percentage of total body water, TBW) and fat-free mass (FFM) were predicted by both the STA and a compartmental model, and compared according to correlation and limits of agreement analysis, with the equivalent data obtained by independent reference methods of measurement (TBW measured by D2O dilution, and FFM measured by dual-energy X-ray absorptiometry). There was a small (2.0 kg) but significant (P < 0.02) difference in mean FFM predicted by the STA, compared with the reference technique in the males, but not in the females (-0.4 kg) or in the combined group (0.8 kg). Both methods were highly correlated. Similarly, small but significant differences for predicted mean ECW volume were observed. The limits of agreement for FFM and ECW were -7.5-9.9 and -4.1-3.0 kg, respectively. Both FFM and ECW (as a percentage of TBW) are well predicted by the STA on a population basis, but the magnitude of the limits of agreement with reference methods may preclude its usefulness for predicting body composition in an individual. In addition, the theoretical basis of an impedance method that does not include a measure of conductor length requires further validation. (C) Elsevier Science Inc. 2000.

Experimental study of phase equilibria in the "FeO"-ZnO-(CaO+SiO2) system with CaO/SiO2 weight ratios of 0.33, 0.93, and 1.2 in equilibrium with metallic iron

The pseudoternary sections FeO-ZnO-(CaO + SiO2) with CaO/SiO2 weight ratios of 0.33, 0.93, and 1.2 in equilibrium with metallic iron have been experimentally investigated in the temperature range from 1000 degreesC to 1300 degreesC (1273 to 1573 K). The liquidus surfaces in these pseudoternary sections have been experimentally determined in the composition range from 0 to 33 wt pct ZnO and 30 to 70 wt pct (CaO + SiO2). The sections contain primary-phase fields of wustite (FexZn1-xO1+y), zincite (ZnzFe1-zO), fayalite (Fu(w)Zn(2-w)SiO(4)), melilite (Ca2ZnuFe1-uSi2O7), willemite (ZnvFe2-vSiO4), dicalcium silicate (Ca2SiO4), pseudowollastonite and wollastonite (CaSiO3), and tridymite (SiO2). The phase equilibria involving the liquid phase and the solid solutions-have also been measured.

Analysis of Approaches to Controllership in Mater`s Thesis from Post-graduate Programs in Accounting Sciences

The objective of the Study is to analyze approaches in master`s thesis in Brazilian Post-Graduate Programs in Accounting Sciences in relation to Controllership, in terms of their conceptual, procedural and organizational aspects, as proposed by Borinelli (2006). The research is descriptive and it uses a quantitative approach. The sample consists of 26 master`s thesis which have the word ""Controllership"" in their titles. Resulting from analysis, in Perspective I (conceptual aspects), in which the elements of definition, object of study and relationship with other sciences were referenced, consensus among authors of the master`s thesis was not verified. In Perspective II (procedural aspects), which deals with activities and functions of Controllership by means of how they materialize as areas of knowledge within organizations, it was observed that the approach in the master`s thesis is quite differentiated in terms of the scope of activities. In relation to Perspective III (organizational aspects), there is also no consensus about what constitutes typical Controllership activities, but master`s thesis do include in the definition of Controllership the idea that it is a service or function of information. It was concluded that the approach to controllership, in terms of its conceptual, procedural and organizational aspects is similar to the elements proposed by Borinelli (2006).

Customer Perception about Loyalty Programs in Agricultural Market: a case study

This study discusses the use of loyalty programs and Customer perception in, agricultural market. The theoretical review includes relationship marketing, its objectives, dimensions and instruments, and loyalty programs. The method for the empirical part consisted on qualitative research, through a case study conducted at one of the largest crop protection chemical companies in Brazil. The case is representative once this company was pioneer in its segment in adopting the customer relationship management. (CRM) approach to-their clients: It has been a consensus that customer relationship is a tool to amplify the Customer share. This.,is so, due the. increasing competition generated by the entrance of generic products and the retaliation actions adopted by the multinational groups. The case study includes a market overview, a description of the company, its loyalty program, the image of the program from the customer`s perspective, and the main results acquired with the CRM program. The Study also presents some recommendations for-companies that are pursuing strategies to. increase their customer share through loyalty programs.

The food business environment and the role of China and Brazil building a ""food bridge""

Purpose - The purpose of this paper is to discuss the economic crisis of 2008/2009 and the major impacts on developing nations and food-producing countries Within this macro-environment of food chains, there is concern that food inflation might come back sooner than expected The role of China as one of the major food consumers in the future, and Brazil, as the major food producer, is described as the food bridge, and an agenda of common development of these countries suggested. Design/methodology/approach - This paper reviews literature on muses of food inflation, production shortages, and investigation of programs to solve the problem in the future, it is also based on author`s personal insights and experience of working on this field in the last 15 years, and recent discussions in forums and interviews Findings - The major factors that jointly caused food prices increase in 2007/2008 were population growth, Income distribution, urbanization, dollar devaluations, commodity funds, social programs, production shortages, and bionic`s A list of ten policies is suggested. horizontal expansion of food production, vertical expansion, reduction in transaction costs, in protectionism and other taxes, investment in logistics, technology and better coordination, contracts, new generation of fertilizers and to use the best sources of biofuels. Originality/value - Two major outputs from this paper are the ""food demand model"" that inserts in one model the trends and muses of food inflation and the solutions, and the ""food bridge concept"" that also aligns in one box the imminent major food chain cooperation between China and Brazil

Program sustainability of a community-based intervention to prevent falls among older Australians

Multi-strategy interventions have been demonstrated to prevent falls among older people, but studies have not explored their sustainability. This paper investigates program sustainability of Stay on Your Feet (SOYF), an Australian multi-strategy falls prevention program (1992-1996) that achieved a significant reduction in falls-related hospital admissions. A series of surveys assessed recall, involvement and current falls prevention activities, 5 years post-SOYF in multiple original SOYF stakeholder groups within the study area [general practitioners (GPs), pharmacists, community health (CH) staff shire councils (SCs) and access committees (ACs)]. Focus groups explored possible behavioural changes in the target group. Surveys were mailed, except to CH staff and ACs. who participated in guided group sessions and were contacted via the telephone, respectively. Response rates were: GPs. 67% (139/209); pharmacists, 79% (53/67); CH staff, 63% (129/204); SCs, 90% (9/10); ACs, 80% (8/10). There were 73 older people in eight focus groups. Of 117 GPs who were practising during SOYF 80% recalled SOYF and 74% of these reported an influence on their practice. Of 46 pharmacists operating a business during SOYF, 45% had heard of SOYF and 79% of these reported being 'somewhat' influenced. Of 76 community health staff (59%) in the area at that time, 99% had heard of SOYF and 82% reported involvement. Four SCs retained a SOYF resource, but none thought current activities were related. Seven ACs reported involvement, but no activities were sustained. Thirty-five focus group participants (48%) remembered SOYF and reported a variety of SOYF-initiated behaviour changes. Program sustainability was clearly demonstrated among health practitioners. Further research is required to assess long-term effect sustainability.

Self-assembled naphthalenediimide derivative films for light-assisted electrochemical reduction of oxygen

This naphthalene diimide derivative, DC18, forms highly conjugated semiconducting stacked assemblies over electrodes after electrochemical conditioning. These molecular materials are very efficient towards electrochemical photoreduction of oxygen under visible light.

ANNA: A new prediction method for bioassessment programs

1. Cluster analysis of reference sites with similar biota is the initial step in creating River Invertebrate Prediction and Classification System (RIVPACS) and similar river bioassessment models such as Australian River Assessment System (AUSRIVAS). This paper describes and tests an alternative prediction method, Assessment by Nearest Neighbour Analysis (ANNA), based on the same philosophy as RIVPACS and AUSRIVAS but without the grouping step that some people view as artificial. 2. The steps in creating ANNA models are: (i) weighting the predictor variables using a multivariate approach analogous to principal axis correlations, (ii) calculating the weighted Euclidian distance from a test site to the reference sites based on the environmental predictors, (iii) predicting the faunal composition based on the nearest reference sites and (iv) calculating an observed/expected (O/E) analogous to RIVPACS/AUSRIVAS. 3. The paper compares AUSRIVAS and ANNA models on 17 datasets representing a variety of habitats and seasons. First, it examines each model's regressions for Observed versus Expected number of taxa, including the r(2), intercept and slope. Second, the two models' assessments of 79 test sites in New Zealand are compared. Third, the models are compared on test and presumed reference sites along a known trace metal gradient. Fourth, ANNA models are evaluated for western Australia, a geographically distinct region of Australia. The comparisons demonstrate that ANNA and AUSRIVAS are generally equivalent in performance, although ANNA turns out to be potentially more robust for the O versus E regressions and is potentially more accurate on the trace metal gradient sites. 4. The ANNA method is recommended for use in bioassessment of rivers, at least for corroborating the results of the well established AUSRIVAS- and RIVPACS-type models, if not to replace them.