Materials Surgery – Reactivity Differences of Organic Groups in Hybrids

Synergistic properties in hybrid materials can emerge if the inorganic matrix has an electronic influence on the organic constituents and vice versa. This paper describes the drastic effect of SiO₂ in periodically ordered mesoporous organosilica materials (PMOs) on ethylene groups. A sophisticated, in situ solid‐state NMR spectroscopy study showed that the ozonolysis of ethylene groups follows an entirely different mechanism than is normal for organic, molecular groups. Ultimately, this leads to the topotactic transformation of the PMO material. Only if silicon is not in the alpha position to the double bond does it became possible to establish a new method to functionalize PMOs materials: the targeted scission of the ethylene group and the creation of functionalized pockets inside the pore walls of the mesoporous solid.     

Nutrient redistribution by grazing cattle drives patterns of topsoil N and P stocks in a low-input pasture ecosystem

Nutrient cycles in grassland often involve net transfers from some areas to others. Here, we analyse patterns of N and P transfers by cattle in two grazing periods, and their relationships to soil P and N stocks in an unfertilised old pasture with a history of >50 years grazing. Net transfers were assessed from spatial patterns of nutrient ingestion and excretion. Total soil N and P were determined at 0–5, 5–10, 10–30 and 30–60 cm. All analyses were performed with a spatial resolution of 10 × 10 m² or higher. Data were geostatistically interpolated. Nutrients accumulated in the flat crest zone and were depleted in the steeper areas. Nutrient ingestion was less and excretion higher in the accumulation zone (and vice versa in the depletion zone) revealing that both components of grazer-driven net transfers of nutrients promoted the development of accumulation/depletion zones. Topsoil stocks of N and P were closely correlated with excreta density and net transfers of N (P < 0.001), whereas N and P at 30–60 cm displayed only weak or no correlation. Redistribution involved a small fraction of the soil stocks: nutrients grazed in two periods were equivalent to 0.8% of N and 0.2% of P of the whole pasture (0–60 cm). These factors suggest that topsoil nutrient distribution was modified by long-term stable patterns of net transfers of nutrients. The excess of N in the accumulation zone (N in accumulation zone minus N in depletion zone, in 0–60 cm) was 11 times larger than that of annual (i.e. short-term) net transfers; but for P, it was 30 times larger. This contrast likely derived from leaching/volatilization losses of N in the accumulation zone and only small inputs of biologically fixed N in the depletion zone. The nitrogen status of vegetation (Nitrogen Nutrition Index) had a strong effect on herbage production throughout the pasture, while the Phosphorus Nutrition Index indicated no limitation, except in urine patches.     

Evolutionary functional black-box testing in an industrial setting

During the past years, evolutionary testing research has reported encouraging results for automated functional (i.e. black-box) testing. However, despite promising results, these techniques have hardly been applied to complex, real-world systems and as such, little is known about their scalability, applicability, and acceptability in industry. In this paper, we describe the empirical setup used to study the use of evolutionary functional testing in industry through two case studies, drawn from serial production development environments at Daimler and Berner & Mattner Systemtechnik, respectively. Results of the case studies are presented, and research questions are assessed based on them. In summary, the results indicate that evolutionary functional testing in an industrial setting is both scalable and applicable. However, the creation of fitness functions is time-consuming. Although in some cases, this is compensated by the results, it is still a significant factor preventing functional evolutionary testing from more widespread use in industry.     

On the Complexity of Iterated Weak Dominance in Constant-Sum Games

In game theory, an action is said to be weakly dominated if there exists another action of the same player that, with respect to what the other players do, is never worse and sometimes strictly better. We investigate the computational complexity of the process of iteratively eliminating weakly dominated actions (IWD) in two-player constant-sum games, i.e., games in which the interests of both players are diametrically opposed. It turns out that deciding whether an action is eliminable via IWD is feasible in polynomial time whereas deciding whether a given subgame is reachable via IWD is NP-complete. The latter result is quite surprising, as we are not aware of other natural computational problems that are intractable in constant-sum normal-form games. Furthermore, we slightly improve on a result of V. Conitzer and T. Sandholm by showing that typical problems associated with IWD in win-lose games with at most one winner are NP-complete.     

Assessment of vascularity in reactive lymph nodes by means of D-galactose contrast-enhanced Doppler sonography

ERPs to target stimulation with tone, picture and characters of Chinese words ([symbol: see text] CCW were target stimulus) were studied in adolescents group and aged persons group. The age of the adolescent group ranged from 15-17 years, with 30 males and 30 females; the age of the elderly persons group ranged from 60-79 years with 29 males and 18 females. The latencies of N2 of aged persons in tone stimulus and in picture stimulus among males were longer than those of adolescents. The latencies of P3 and RT of aged persons were longer than those of adolescents in three stimulus models. The gender differences of latencies of N2 and RT were not obvious in two groups, but were apparent in P3 in adolescents. The latencies of N2, P3 and RT of CCW stimulus were longer compared to those of picture stimulus in the adolescent group, but not in the aged persons group.