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Using a recursion model with real parameters of Nabis pseudoferus, we show that its filial cannibalism is an optimal foraging strategy for life reproductive success, but it is not an evolutionarily optimal foraging strategy, since it cannot maximize the descendant's number at the end of the reproductive season. Cannibalism is evolutionarily rational, when the number of newborn offspring produced from the cannibalized offspring can compensate the following two effects: (a) The cannibalistic lineage wastes time, since the individuals hatched from eggs produced by cannibalism start to reproduce later. (b) Cannibalism eliminates not only one offspring, but also all potential descendants from the cannibalized offspring during the rest of reproductive season. In our laboratory trials, from conspecific prey Nabis pseudoferus did not produce newborn nymphs enough to compensate the above two effects. [ABSTRACT FROM AUTHOR]

A vertex subset S of a graph G is said to 2-dominate the graph if each vertex not in S has at least two neighbors in it. As usual, the associated parameter is the minimum cardinal of a 2-dominating set, which is called the 2-domination number of the graph G. We present both lower and upper bounds of the 2-domination number of cylinders, which are the Cartesian products of a path and a cycle. These bounds allow us to compute the exact value of the 2-domination number of cylinders where the path is arbitrary, and the order of the cycle is n ≡ 0 (mod 3) and as large as desired. In the case of the lower bound, we adapt the technique of the wasted domination to this parameter and we use the so-called tropical matrix product to obtain the desired bound. Moreover, we provide a regular patterned construction of a minimum 2-dominating set in the cylinders having the mentioned cycle order. [ABSTRACT FROM AUTHOR]

The pandemic reminded us that the pathogen evolution still has a serious effect on human societies. States, however, can prepare themselves for the emergence of a novel pathogen with unknown characteristics by analysing potential scenarios. Game theory offers such an appropriate tool. In our game-theoretical framework, the state is playing against a pathogen by introducing non-pharmaceutical interventions to fulfil its socio-political goals, such as guaranteeing hospital care to all needed patients, keeping the country functioning, while the applied social restrictions should be as soft as possible. With the inclusion of activity and economic sector dependent transmission rate, optimal control of lockdowns and health care capacity management is calculated. We identify the presence and length of a pre-symptomatic infectious stage of the disease to have the greatest effect on the probability to cause a pandemic. Here we show that contrary to intuition, the state should not strive for the great expansion of its health care capacities even if its goal is to provide care for all requiring it and minimize the cost of lockdowns. [ABSTRACT FROM AUTHOR]