Meshless methods have become an effective tool for solving problems from engineering practice in last years. They have been successfully applied to problems in solid and fluid mechanics. One of their advantages is that they do not require any explicit mesh in computation. This is the reason why they are useful in the case of large deformations, crack propagations and so on. Reproducing kernel particle method (RKPM) is one of meshless methods. In this contribution we deal with some modifications of the RKPM. The construction of the methods considered is given together with simple examples of their applications to solving boundary value problems.
Hyssopus pallidus (Askew) (Hymenoptera: Eulophidae) is a gregarious ectoparasitoid of late larvae of the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). In the present work reproduction and the development and morphology of the immature stages were studied. Five larval instars were differentiated by the shape and size of the mandibles. The larvae are hymenopteriform with a weakly sclerotized head and 13 segments. The first instar has four pairs of spiracles, while the other four instars have nine pairs. Under laboratory conditions of 22-24°C and 60-80% RH the egg stage lasted 1.5 days, the larval instars 6.3 days, and the pupal stage 7.9 days in females and 7.2 days in males. The duration of each of the five larval instars (L1-L5) is approximately 1, 0.5, 0.75, 0.75 and 3.5 days, respectively. Male and female development time does not differ significantly in the egg and larval stages, but differences are highly significant in the pupal stage. Male and female pupae can be differentiated by their sexual rudiments. Copulation takes place immediately upon emergence of the females between siblings, adult males appearing before the females. Females in culture with access to an energy source can survive for more than 60 days. They are synovigenic: they emerge with no mature eggs in their ovaries and take the first two days after emergence to mature the full set of around 24-30 eggs. They continue paralyzing hosts, ovipositing and maturing eggs for as long as they live. After an oviposition a female needs two to three days to mature a new full set of eggs. Age and feeding influence egg load. Oösorption is significant in starved females, but also occurs in older fed females with no host contact.
Parameters of breeding were studied in seven rookeries in the agricultural landscape of eastern Poland. Within foraging territories near colonies, proportions of environmental components were defined, and avoided and preferred types of crops were distinguished. The mean clutch size, mean number of hatchlings and mean number of fledglings per successful brood did not differ between colonies and did not depend on colony size. In contrast, total losses at the stage of egg incubation and feeding chicks, the mean number of fledglings calculated per breeding pair and the overall breeding success were different. Foraging territories around each colony usually had different proportions of preferred and avoided crops. Breeding success depended positively on the area of preferred crops: spring cereals and meadows and pastures. Breeding success seemed to decrease with the area covered by avoided crops and winter crops, but the relationship was not significant. The area of spring cereals was positively but not significantly correlated with the mean number of fledglings.
In Sardinia island (Central Italy) the wild boar is originally present with an endemic subspecies, Sus scrofa meridionalis. To evaluate its demographic and reproductive characteristics, we analysed data on the harvest bags of two hunting seasons (2011-2012 and 2012-2013) in the province of Olbia-Tempio (North-Eastern Sardinia). We collected data of 325 Sardinian wild boars. Sex-ratio did not differ significantly from the theoretical distribution 1:1. We examined 175 females; thirty-five percent of them were in breeding
condition, with 56 pregnant and five lactating females. Gestation was more frequent in heavier females than in the lighter ones. The mean number of foetuses per litter was 4.2 ± 1.2 (range two-seven), with no differences between the hunting seasons. There was an evidence of seasonality in reproduction period; the mating season appeared to occur primarily in late autumn and in winter, whereas farrowing mainly occurred from March to May (56 % of births), with a minimum in summer (5 % of births).
Absolute fecundity (Fa) of burbot Lota lota lota females from Lake Haƒcza was 47.3 - 439.8 × 103, the relative fecundity based on eviscerated weight (Fwo) was 617.9 - 1572 × 103, and that based of total weight (Fw) was 44.8 - 1234.5 × 103. Regression equations were calculated, approximating the most significant relationships between fecundity and total body length of burbot (Fa = 0.0138 Sl2.5678, Fa = 0,0099 Tl2.8129) and weight (Fa = 0.6481 W1.0144). Mean gonadosomatic indexes (GSI) increased slightly with body length from 3.9 to 8.8% for females and from 3.7 to 20.6% for males.
The breeding and sexual maturation properties of a cyprinid fish Capoeta tinca were studied in Gelingüllü Reservoir, a recently impounded dam in Central Anatolia. Ripening of gonads commenced in early spring, whereas spawning occurred between May and June. Sexual maturity age was 2+ for males and 3+ for females. The results obtained from this study were compared with those of other populations of C. tinca in Turkey.
Reproductive traits are among the most important biological characteristics that facilitate or impede the establishment of non-native fish into new environments. In several tributaries of the Lower River Danube (Bulgaria), the round goby (Neogobius melanostomus Pallas, 1814) is a recent invader. Specimens from the edge of the invasion front were collected monthly (March 2017 to May 2018) from each river. The pioneer individuals displayed relatively small body sizes. First maturation of females occurs at 49 mm total length. Based on the dynamics of oocyte size and GSI, it was established that spawning begins in early spring, at a relatively low water temperature (6-7 °C). The breeding season extended from March to June. Average absolute fecundity was 162 ± 62 oocytes, while average relative fecundity was 94 oocytes/g ± 24. Female fecundity is linearly dependent on the length and weight. Both of the known male alternative reproductive tactics were observed. Body condition factor was lowest during April for both sexes. The relationship between reproductive traits and invasive potential in N. melanostomus is discussed.
The reproductive biology of the marbled goby, Pomatoschistus marmoratus (Risso, 1810), was studied in the Strymon River estuarine system (northern Greece) between September 1997 and August 1999. Samplings were conducted on a monthly basis at the mouth of the river using a bag seine net and overall a total of 4 563 individuals were collected. The total length of males ranged between 2.5 and 6.0 cm and that of females between 2.8 and 5.7 cm, while that of unsexed individuals ranged between 1.2 and 2.9 cm. Sex ratio was 1.54:1 in favour of the females and statistically different from unity. The spawning of the species was extended, occurring between February and May. Mean absolute fecundity (F) was 1 386 (SE=8) oocytes and showed a significant positive exponential relationship with total length (F=14.387TL2.92), and total weight (F=1351TW0.83) of the fish. The relative fecundity ranged between 878 and 3 444 oocytes/g of total weight. Mean size at first maturity was estimated at 3.82 cm for the females and 4.66 cm for the males.
Paysandisia archon (Burmeister, 1980) (Lepidoptera: Castniidae) is an accidentally introduced pest that damages palm trees in the northern Mediterranean area. To our knowledge, there are no experimental studies on its mating behaviour, and little is known about its biology and ecology. In the present study, we used outdoor experiments to investigate several characteristics of the reproductive behaviour of P. archon: sexual maturity, diel periodicity of mating, occurrence of polyandry and delay between mating and laying eggs. The results indicate that 73% of the individuals studied were sexually mature three hours after adult emergence. Mating peaked between 14:00 h and 15:00 h and 87% of the females were fertilized and started laying eggs 1.25 (± 1.14) days after mating. Females were generally monandrous, but nevertheless remained attractive after mating. The results of this study provide the necessary background knowledge for studying several aspects of P. archon reproductive biology, in particular oviposition, sex pheromones and their role in mediating mating behaviour in this pest. These results are the first step in developing tools for monitoring populations of this pest., Roxane Delle-Vedove ... [et al.]., and Obsahuje seznam literatury