We investigate the effect of seed predation on the coexistence of competing annual plants. We demonstrate a role for predation that is opposite to the conventional wisdom that predation promotes coexistence by reducing the intensity of competition. In the common situation where competitive coexistence involves intraspecific competition exceeding interspecific competition, predation can undermin...

Correlations between acoustic properties and bone density were investigated in the 12 defatted bovine cancellous bone specimens in vitro. Speed of sound (SOS) and broadband ultrasonic attenuation (BUA) were measured in three different frequency bandwidths from 0.5 to 2 MHz using three matched pairs of transducers with the center frequencies of 1, 2.25, and 3.5 MHz. The relative orientation betw...

Apparent actions We assume that a passive observer perceives a sequence S of sensor values (s1, ..., sT ) with T ∈ N. At each instance t of the sequence, the observer has a memory or knowledge state mt which gives us a second sequence M = (m1, ...,mT ). The memory state of the agent might contain models of the observations or not. In the course of a sequence S there is an apparent action for ob...

This study examines the variability in the anatomy of mandibles of differing ages and different stages of tooth loss. Mandibles from individuals between 19 and 96 y were sectioned into 2 mm thick vertical plane-parallel slices and cleaned of marrow and periosteum. The apparent density (mass per unit volume in g/ml) from midline (MID) and mental foramen region (MF) sites was determined by weighi...

When the transmittance of a filter on a bicolored background is varied, the lightness differences that vary are those between the filter and the background and that between the parts inside the filter. It is hypothesized that these are the differences of importance for the valuation of the apparent density of the transparent layer. The results of two experiments seem to show that the rated appa...

Microwave technology has a potential application in the extraction of zinc from sulphide ores, knowledge of the dielectric properties of these ores plays a major role in the microwave design and simulation for any process. The dielectric properties of zinc sulfide concentrate for two different apparent densities—1.54 and 1.63 g/cm3—have been measured by using the resonance cavity perturbation t...

Temporal changes and altitudinal distribution of aerobic anoxygenic phototrophs in 1 mountain lakes 2 3 Zuzana Čuperová, Evelyn Holzer, Ivette Salka, Ruben Sommaruga, Michal 4 Koblížek 5 6 7 8 Institute of Microbiology CAS, Opatovický mlýn, 37981 Třeboň, Czech Republic 9 University of South Bohemia, Faculty of Science, Branišovská 31, 370 05 České Budějovice, 10 Czech Republic 11 Laboratory of ...