Aphid parasitoids from Malta (Hymenoptera, Braconidae, Aphidiinae)

Six aphid parasitoids are listed including three species which are recorded for the fi rst time from the Maltese islands, namely Aphidius funebris, Ephedrus persicae and Lysiphlebus confusus. Aphidius colemani, a species which was introduced for the control of greenhouse aphids, was also found for the fi rst time in the open.peer-reviewe

Pauesia silana Tremblay, 1969 a parasitoid of Cinara-aphids on Conifers in Malta (Hymenoptera: Braconidae: Aphidiinae)

Pauesia silana is recorded for the first time from Malta and the Lefkada and Meganissi islands in Greece. From Malta, the species was reared from Cinara palaestinensis on Pinus halepensis from material collected from Buskett. From the Greek islands, the species was collected on Cinara sp. on the same mentioned hostplant. The new record contributes to the information on its distribution, hosts and plant associations in the Mediterranean area.peer-reviewe

Lipolexis gracilis Förster, 1862 - new record of an aphid parasitoid from Malta (Hymenoptera, Braconidae, Aphidiinae)

Lipolexis gracilis, an aphid parasitoid reared from a species of Aphis associated with Papaver is newly recorded from Malta. A check-list of the Aphidiinae known from Malta is given.peer-reviewe

Fast-slow asymptotics for a Markov chain model of fast sodium current

We explore the feasibility of using fast-slow asymptotic to eliminate the computational stiffness of the discrete-state, continuous-time deterministic Markov chain models of ionic channels underlying cardiac excitability. We focus on a Markov chain model of the fast sodium current, and investigate its asymptotic behaviour with respect to small parameters identified in different ways.Comment: 16 pages, 6 figures, as accepted to Chaos 2017/09/0

Exponential integrators for a Markov chain model of the fast sodium channel of cardiomyocytes

The modern Markov chain models of ionic channels in excitable membranes are numerically stiff. The popular numerical methods for these models require very small time steps to ensure stability. Our objective is to formulate and test two methods addressing this issue, so that the timestep can be chosen based on accuracy rather than stability. Both proposed methods extend Rush-Larsen technique, which was originally developed to Hogdkin-Huxley type gate models. One method, "Matrix Rush-Larsen" (MRL) uses a matrix reformulation of the Rush-Larsen scheme, where the matrix exponentials are calculated using precomputed tables of eigenvalues and eigenvectors. The other, "hybrid operator splitting" (HOS) method exploits asymptotic properties of a particular Markov chain model, allowing explicit analytical expressions for the substeps. We test both methods on the Clancy and Rudy (2002) INa Markov chain model. With precomputed tables for functions of the transmembrane voltage, both methods are comparable to the forward Euler method in accuracy and computational cost, but allow longer time steps without numerical instability. We conclude that both methods are of practical interest. MRL requires more computations than HOS, but is formulated in general terms which can be readily extended to other Markov Chain channel models, whereas the utility of HOS depends on the asymptotic properties of a particular model. The significance of the methods is that they allow a considerable speed-up of large-scale computations of cardiac excitation models by increasing the time step, while maintaining acceptable accuracy and preserving numerical stability.Comment: 9 pages, 5 figures main text + 14 pages, 1 figure appendix, as submitted in final form to IEEE TBME 2014/11/11. Copyright IEEE (2014

Manchu Names and Some Problems Concerning their Transcription

No abstrac

Zur Geschichte der Mandschuristik in Italien

No abstrac

Further contributions to the tritrophic plant-aphid-parasitoid associations in Malta with special reference to Aphis nerii (Hemiptera, Aphidoidea) as a prevalent refugium of Aphidiinae (Hymenoptera, Braconidae)

Four species of aphid parasitoids, namely Aphidius colemani, Binodoxys angelicae, Lysiphlebus fabarum and Lysiphlebus testaceipes were reared from Aphis nerii on Nerium oleander and/or Stephanotis floribunda in Malta. Aphidius colemani was the most abundant, occurring in different habitat types. Binodoxys angelicae represents a confirmation of a doubtful past record, while Lysiphlebus testaceipes is a new record for Malta. Aphis nerii is evaluated as a refugium of several aphid parasitoids in Malta. Praon yomenae, another new record for Malta is also included in the present work.peer-reviewe

Aphids and their parasitoids on the Canary grass, Phalaris canariensis in Malta (Hymenoptera, Braconidae, Aphidiinae)

Adialytus ambiguus and Diaeretiella rapae were reared from Rhopalosiphum padi on the Canary grass, Phalaris canariensis in Malta. The identity to species level of the Adialytus required confirmation via DNA analysis of the respective species group. Some ecosystem interrelationships derived from the determined food webs are discussed.peer-reviewe