Horizontal mergers, firm heterogeneity, and R&D investments

We investigate the incentive and the welfare implications of a merger when heterogeneous oligopolists compete both in process R&D and on the product market. We examine how a merger affects the output, investment, and profits of firms, whether firms have merger incentives, and, if so, whether such mergers are desirable from the viewpoint of social welfare. We also derive equilibrium configurations and explore their welfare properties.

Trade and mergers in the presence of firm heterogeneity

We investigate the role of firm heterogeneity in considering profitability and desirability of mergers in the international economy. Analysis shows that higher trade costs make only crossborder mergers profitable whereas larger firm heterogeneity is likely to increase both domestic and cross-border mergers. Furthermore, it is shown that whether or not a merger leads to merger waves depends on the types of firms involved in it. It is also demonstrated that larger firm heterogeneity can reduce the discrepancy between profitability and desirability of mergers when the trade cost is sufficiently low.M&As, trade, firm heterogeneity, Cournot competition

Association between contrast extravasation on computed tomography scans and pseudoaneurysm formation in pediatric blunt splenic and hepatic injury: A multi-institutional observational study

PURPOSE: We aimed to examine the association between contrast extravasation (CE) on initial computed tomography (CT) scan and pseudoaneurysm (PSA) development in pediatric blunt splenic and/or liver injury. METHODS: We conducted a multi-institutional retrospective study in cases of blunt splenic and/or hepatic injury who underwent an initial attempt of nonoperative management. A logistic regression model was used to compare PSA formation and CE on initial CT scan, and the area under the receiver operating characteristic curve (AUC) with and without CE was used to assess the predictive performance of CE for PSA formation. RESULTS: Of 236 cases enrolled from 10 institutions, PSA formation was observed in 17 (7.2%). Multivariate analysis showed a significant association between CE on initial CT scan and increased incidence of PSA formation (odds ratio, 4.96; 95% confidence interval, 1.37-18.0). There was no statistically significant association between the grade of injury and PSA formation. The AUC improved from 0.75 (0.64-0.87) to 0.80 (0.70-0.91) with CE. CONCLUSION: Active CE on initial CT scan was an independent predictor of PSA formation. Selective use of follow-up CT in children who showed CE on initial CT may provide early identification of PSA formation, regardless of injury grade. LEVEL OF EVIDENCE: Prognostic and epidemiological, level III

A High-Yielding Rice Cultivar “Takanari” Shows No N Constraints on CO2 Fertilization

Enhancing crop yield response to elevated CO2 concentrations (E-[CO2]) is an important adaptation measure to climate change. A high-yielding indica rice cultivar “Takanari” has recently been identified as a potential candidate for high productivity in E-[CO2] resulting from its large sink and source capacities. To fully utilize these traits, nitrogen should play a major role, but it is unknown how N levels influence the yield response of Takanari to E-[CO2]. We therefore compared grain yield and quality of Takanari with those of Koshihikari, a standard japonica cultivar, in response to Free-Air CO2 enrichment (FACE, +200 μmol mol−1) under three N levels (0, 8, and 12 g m−2) over three seasons. The biomass of both cultivars increased under E-[CO2] at all N levels; however, the harvest index decreased under E-[CO2] in the N-limited treatment for Koshihikari but not for Takanari. The decreased harvest index of Koshihikari resulted from limited enhancement of spikelet number under N-limitation. In contrast, spikelet number increased in E-[CO2] in Takanari even without N application, resulting in significant yield enhancement, averaging 18% over 3 years, whereas Koshihikari exhibited virtually no increase in yield in E-[CO2] under the N-limited condition. Grain appearance quality of Koshihikari was severely reduced by E-[CO2], most notably in N-limited and hot conditions, by a substantial increase in chalky grain, but chalky grain % did not increase in E-[CO2] even without N fertilizer. These results indicated that Takanari could retain its high yield advantage over Koshihikari with limited increase in chalkiness even under limited N conditions and that it could be a useful genetic resource for improving N use efficiency under E-[CO2]

A new cancer diagnostic system based on a CDK profiling technology

AbstractA series of molecular pathological investigations of the molecules that stimulate the cyclin dependent kinases (CDK1, 2, 4, and 6) have led to enormous accumulation of knowledge of the clinical significance of these molecules for cancer diagnosis. However, the molecules have yet to be applied to clinical cancer diagnosis, as there is no available technology for application of the knowledge in a clinical setting. We hypothesized that the direct measurement of CDK activities and expressions (CDK profiling) might produce clinically relevant values for the diagnosis. This study investigated the clinical relevance of CDK profiling in gastrointestinal carcinoma tissues by using originally developed expression and activity analysis methods. We have established novel methods and an apparatus for analyzing the expression and activities of the CDK molecules in lysate of tumor tissue in a clinical setting, and examined 30 surgically dissected gastrointestinal carcinomas and corresponding normal mucosal specimens. We demonstrate here that remarkably elevated CDK2 activity is evident in more than 70% of carcinoma tissues. Moreover, a G1-CDK activity profiling accurately mirrored the differences in proliferation between tumor and normal colonic tissues. Our results suggest that CDK profiling is a potent molecular–clinical approach to complement the conventional pathological diagnosis, and to further assist in the individualized medications