Market returns to acquirers of substantial assets

Does poor post-acquisition performance characterise firms that make non-M&A acquisitions? We investigate the wealth effects of substantial asset acquisitions (i.e. acquisitions that cost over $10 million) on acquiring firms' shareholders. We find significant abnormal positive market reaction to asset acquisition announcements and, contrary to findings for firms undertaking M&As, the acquiring firms perform exceptionally well post-acquisition. Our findings are robust to the research method weaknesses common to many studies of long-term performance and we control for free-cash-flow as well. Our results contradict the hubris hypothesis of acquisitions and lend weight to the argument that the auction-style process that characterizes corporate takeover bids contributes to overpayment

The Demutualisation of the Australian Stock Exchange: Causes and Consequences

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An adaptive design approach for defects distribution modeling in materials from first-principle calculations

Designing and understanding the mechanism of non-stoichiometric materials with enhanced properties is challenging, both experimentally and even computationally, due to the large number of chemical spaces and their distributions through the material. In the current work, it is proposed a Machine Learning approach coupled with the Efficient Global Optimization (EGO) method—an Adaptive Design (AD)—to model local defects in materials from first-principle calculations. Our method takes into account the smallest sample set as possible, envisioning the material defect structure relationship with target properties for new insights. As an example, the AD framework allows us to study the stability and the structure of the modified goethite (Fe0.875Al0.125OOH) by considering a proper defect distribution, from first-principle calculations. The chemical space search for the modified goethite was evaluated by starting from different sizes and configurations of the samples as well as different surrogate models (ANN and Gaussian Process; GP), acquisition functions, and descriptors. Our results show that the same local solution of several defect arrangements in Fe0.875Al0.125OOH is found regardless of the initial sample and regression model. This indicates the efficiency of our search method. We also discuss the role of the descriptors in the accelerated global search for defects in material modeling. We conclude that the AD method applied in material defects is a successful approach in automating the search within huge chemical spaces from first-principle calculations by considering small samples. This method can be applied to mechanistic elucidation of non-stoichiometric materials, solid solutions, alloys, and Schottky and Frenkel defects, essential for material design and discovery

Electronic Properties and Charge Transfer of Topologically Protected States in Hybrid Bismuthene Layers

We have performed first-principles calculations of electronic and dielectric properties of single-layer bismuth (bismuthene) adsorbed with −COOH groups. We show that in a high coverage regime, the Bi–COOH hybrid structure is a two-dimensional topological insulator with protected edge Dirac states. The adsorption process of −COOH induces a planar configuration to the initially pristine buckled bismuthene. We claim that the stability of these planar structures mainly stems from strain induced by the adsorption of the −COOH organic group, but it is also related to ligand–ligand interactions. Furthermore, we demonstrate that many-body corrections are crucial to obtain a proper description of the electronic and dielectric properties of the investigated hybrid systems. Analysis of the charge density shows that the role of this organic group is not only to stabilize the layer but also to functionalize it, which is very important for future applications such as sensing and biomolecules immobilization, as well as in electronic spintronic and even optical devices

CHEMICAL CHARACTERIZATION AND ANTIMICROBIAL ACTIVITY OF HYDROETHANOLIC CRUDE EXTRACT OF EUGENIA FLORIDA DC (MYRTACEAE) LEAVES

Objective: The present study aimed to characterize and quantify the total phenolics, flavonoids and tannins in a hydroethanolic crude extract (70% (v/v) (EB)) of the leaves of E. florida DC, as well as to evaluate the antimicrobial activity of the extract against different species of micro-organisms.Methods: EB was characterized using a mass spectrometer equipped with a direct insertion device for in-stream injection (FIA). Quantitative analyses of major compounds were carried out by spectrophotometry. In addition, we evaluated the sensitivity profiles of different strains of yeast and bacteria against different concentrations of EB.Results: The classes found were in agreement with those described in the literature: flavonoids, tannins, phenolic acids and saponins. EB showed levels of phenolic compounds, flavonoids and tannins equal to 25.82 mg gallic acid equivalents per gram of extract (EAG/g), 8.42 mg quercetin equivalents per gram of extract (EQ/g) and 7.30 mg tannic acid equivalents per gram of extract (AT/g), respectively. In the analysis of antimicrobial activity, EB was more active against yeasts but was not effective against the bacteria used in the test.Conclusion: We can conclude that E. florida DC has antimicrobial potential, due to the presence of bioactive secondary metabolites.Keywords: Phenolics, Micro-organisms, Mass spectrometer, Yeasts, Bacteria, PotentialÂ

Cryopreservation of Coffea canephora Pierre ex A. Froehner seeds: importance of drying rate and moisture content.

Seeds of the Coffea canephora species are considered more recalcitrant than those of the Coffea arabica species. They tolerate partial dehydration and they cannot be stored in conventional seed banks at -18ºC because they are sensitive to freezing temperatures. Cryopreservation is a reliable method for storing seeds with these characteristics for long periods. However, preliminary studies are necessary to determine ideal storage conditions. The aim of this study was to investigate the ideal physical and physiological conditions for cryopreservation of Coffea canephora seeds to reduce seed mortality caused by the formation of intracellular ice crystals and to avoid cell damage caused by excessive desiccation. Seeds were subjected to rapid drying in silica gel and slow drying in saturated NaCl solution to moisture contents of 0.20, 0.25, and 0.28 g.g-¹ (dry basis), followed by direct immersion in liquid nitrogen for rapid freezing. Physiological and biochemical analyses were performed to evaluate seed quality before and after cryopreservation. Rapid drying of Coffea canephora seeds to values near 0.20 g.g-1 (db) does not cause reduction in physiological quality. Moisture content of 0.25 g.g-¹ brings about greater survival of Coffea canephora seeds after cryopreservation. Drying rate affects the physiological quality of cryopreserved Coffea canephora seeds, and rapid drying in silica gel is more favorable than slow drying in a saturated NaCl solution. The activity of the enzymes catalase, esterase, glutamic oxaloacetic transaminase, and polyphenol oxidase are indicators of seed quality for Coffea canephora seeds subjected to cryopreservation