The Chromosomes of three species of the Nasonia complex (Hymenoptera, Pteromalidae).

Die Ergebnisse der Untersuchung des Karyotyps der Schwesterarten Nasonia vitripennis (Walker, 1836), N. longicornis Darling, 1990 und N. giraulti Darling, 1990 werden mitgeteilt. Für die beiden letztgenannten Arten liegen bisher keine karyologischen Daten vor. Die Karyotypen der drei untersuchten Arten mit n=5 und 2n=10 bestehen aus metacentrischen Chromosomen. Die Verteilung des konstitutiven Chromatins scheint in der Gattung Nasonia Ashmead, 1904 ebenfalls sehr einheitlich zu sein. Demgegenüber ergab die Morphometrie der Chromosomen statistisch signifikante Unterschiede zwischen den drei Arten. Die vorliegenden Daten entsprechen der Abfolge der Artenspaltungen im Nasonia-Komplex, die auf der Basis molekulargenetischer Untersuchungen festgestellt wurde.The karyotypes of three sibling species, Nasonia vitripennis (Walker, 1836), N. longicornis Darling, 1990 and N. giraulti Darling, 1990 were examined, the latter two species for the first time. All species have chromosome numbers of n=5 and 2n=10, their chromosomes being metacentric. The distribution of constitutive heterochromatin also appears to be similar in the genus Nasonia Ashmead, 1904. However, statistical karyotypic differences between studied species were revealed using chromosome morphometrics. These data are consistent with the order of divergence in the Nasonia complex found on the basis of molecular studies

Chromosomes of Aphidius ervi Haliday, 1834 (Hymenoptera: Braconidae).

Die Chromosomenanalyse einiger Laborlinien von Aphidius ervi Haliday, 1834 aus Deutschland ergab n=5 und 2n=10. Allerdings wurden bei einigen weiblichen Tieren einer Population Chromosomensätze mit 2n=12 gefunden. Diese Tiere repräsentieren wahrscheinlich eine thelythoke Linie, die aus einer ursprünglich arrhenotoken Population hervorging. Der Karyotyp mit 2n=12 enthält ein zusätzliches charakteristisches Paar vollständig heterochromatischer akrozentrischer Chromosomen.StichwörterChromosomes, Aphidius ervi, Hymenoptera, Braconidae.Chromosome numbers of n=5 and 2n=10 were found in a few laboratory strains of Aphidius ervi Haliday, 1834 from Germany. However, several females having 2n=12 were detected in one of the populations studied. These females are likely to represent a thelytokous strain originating from an initially arrhenotokous one. The karyotype with 2n=12 has a characteristic additional pair of fully heterochromatic acrocentric chromosomes.KeywordsChromosomes, Aphidius ervi, Hymenoptera, Braconidae

Chromosomes of the genus Arge Schrank, 1802 (Hymenoptera, Argidae): new data and review

Results of the chromosome study of 12 sawfly species of the genus Arge Schrank, 1802 are reviewed, including new data on the karyotypes of A. ciliaris (Linnaeus, 1767) and A. enodis (Linnaeus, 1767) with n = 10. Moreover, the same chromosome number, n = 10, is found in A. ustulata (Linnaeus, 1758), for which n = 8 was previously reported. In addition, n = 8 is confirmed in A. gracilicornis (Klug, 1814). The results of the morphometric analysis of chromosome sets of these four species are given. In the genus Arge, haploid chromosome numbers of n = 8, 10, 11 and 13 were found. Among these sawflies, n = 8 appeared to be the most frequent chromosome number, followed by n = 10. The known data of the chromosome study of these insects are summarized and discussed in the light of phylogeny and taxonomy of the genus Arge

Optimization of the structure of insulating composite materials

The article deals with the interdependent relationship between the properties of a structure and the properties of a material, which sets the task of reducing them, even they are indistinguishable, to a certain integrity. The object of research and analysis in the article is a building structure, which is seen as an open self-organized complex structural system. In the main part, the processes of the formation of structures are considered, as well as the classification of structural elements. The article concludes with structural changes related to the self-support and self-development of the network of active elements, which allow the manifestation of adaptation effects and the design-system to function during the normalized period. The importance of self-organization processes during the development and operation of construction systems allow us to attribute it to a self-organizing system. Thus, the building structure can be represented as an open and complex self-organizing system

Genomic and karyotypic variation in Drosophila parasitoids (Hymenoptera, Cynipoidea, Figitidae)

Abstract Drosophila melanogaster Meigen, 1830 has served as a model insect for over a century. Sequencing of the 11 additional Drosophila Fallen, 1823 species marks substantial progress in comparative genomics of this genus. By comparison, practically nothing is known about the genome size or genome sequences of parasitic wasps of Drosophila. Here, we present the first comparative analysis of genome size and karyotype structures of Drosophila parasitoids of the Leptopilina Förster, 1869 and Ganaspis Förster, 1869 species. The gametic genome size of Ganaspis xanthopoda (Ashmead, 1896) is larger than those of the three Leptopilina species studied. The genome sizes of all parasitic wasps studied here are also larger than those known for all Drosophila species. Surprisingly, genome sizes of these Drosophila parasitoids exceed the average value known for all previously studied Hymenoptera. The haploid chromosome number of both Leptopilina heterotoma (Thomson, 1862) and Leptopilina victoriae Nordlander, 1980 is ten. A chromosomal fusion appears to have produced a distinct karyotype for Leptopilina boulardi (Barbotin, Carton et Keiner-Pillault, 1979)(n = 9), whose genome size is smaller than that of wasps of the Leptopilina heterotoma clade. Like Leptopilina boulardi, the haploid chromosome number for Ganaspis xanthopoda is also nine. Our studies reveal a positive, but non linear, correlation between the genome size and total chromosome length in Drosophila parasitoids. These Drosophila parasitoids differ widely in their host range, and utilize different infection strategies to overcome host defense. Their comparative genomics, in relation to their exceptionally well-characterized hosts, will prove to be valuable for understanding the molecular basis of the host-parasite arms race and how such mechanisms shape the genetic structures of insectcommunities

Archaic adaptive introgression in TBX15/WARS2

A recent study conducted the first genome-wide scan for selection in Inuit from Greenland using SNP chip data. Here, we report that selection in the region with the second most extreme signal of positive selection in Greenlandic Inuit favored a deeply divergent haplotype that is closely related to the sequence in the Denisovan genome, and was likely introgressed from an archaic population. The region contains two genes, WARS2 and TBX15, and has previously been associated with adipose tissue differentiation and body-fat distribution in humans. We show that the adaptively introgressed allele has been under selection in a much larger geographic region than just Greenland. Furthermore, it is associated with changes in expression of WARS2 and TBX15 in multiple tissues including the adrenal gland and subcutaneous adipose tissue, and with regional DNA methylation changes in TBX15

The parasitoid species complex associated with sexual and parthenogenetic Naryciinae (Lepidoptera: Psychidae): Integrating ecological and molecular analyses

This study describes the parasitoid species complex associated with seven closely related species of sexual (Siederia rupi- collella, S. listerella, Dahlica lazuri, D. charlottae and D. lichenella) and parthenogenetic (Dahlica fennicella and D. triquetrella) Naryciinae (Lepidoptera: Psychidae) in Central Finland. A thorough ecological analysis of all the species of parasitoids recorded was combined with analyses of molecular data. Mitochondrial and nuclear DNA data were obtained from all the species in order to (1) detect cryptic species associated with host specialization, (2) assign undescribed males to females, and (3) verify the morphological identification of closely related species. A DNA barcoding technique was employed to identify host species from parasitized larval remains. By sampling more than 10,000 host larvae, of which 25.7% were parasitized, nine parasitoid species were identified mor- phologically, including both koinobionts (Ichneumonidae: Diadegma incompletum, Macrus parvulus, Trachyarus borealis, T. solya- nikovi, T. fuscipes, T. brevipennis and Braconidae: Meteorus affinis) and idiobionts (Ichneumonidae: Orthizema flavicorne, Gelis fuscicornis). Ecological characteristics such as time and mode of host attack, time of emergence and level of specialization differed widely. The results show that differences in parasitoid biology need to be taken into account when studying differences in percentage parasitism of sexual and parthenogenetic Naryciinae. The molecular data revealed that one parasitoid species M. parvulus may con- sist of two cryptic forms associated with the sexual and parthenogenetic hosts, respectively. The data further establishes that T. bre- vipennis and some T. fuscipes are in fact morphotypes of one species. The large variation in mitochondrial DNA within species and its inconsistency with nuclear DNA demonstrate that current species and genus delimitation is inadequate in the Trachyarus species group. Our study shows that it is essential to use DNA barcoding methods when investigating host-parasitoid complexes

Дослідження впливу режимів електронно-променевої безтигельної зонної плавки металургійного кремнію на рафінування та структуроутворення зливків

The paper presents the results of studies obtained with the development of the technology of electron-beam crucible impregnation of metallurgical silicon. It is shown that refining of silicon from background and dopant impurities in electron-beam crucible-free zone melting occurs by zone purification during melting and as a result of evaporation of impurities from the sample surface.  The mathematical model and computational experiment were been performed to determine the temperature gradient at different rates of zone melting. It was found the diapason of temperature gradients, which provides the columnar structure of crystallites and the purification of the samplesdue the melting with the zone recrystallization procedure. The level of the resistivity of the ingots increases at the end.У роботі представлені результати досліджень, які отримані при розробці технології електронно-променевої безтигельної зонної плавки металургійного кремнію. Показано, що рафінування кремнію від фонових і легуючих домішок при електронно-променевій безтигельній зонній плавці відбувається шляхом зонного очищення при плавці і в результаті випаровування домішок з поверхні зразка. Створено математичну модель і проведено обчислювальний експеримент, за допомогою якого визначено температурний градієнт при різних швидкостях зонного плавлення. Встановлено межі температурних градієнтів, при яких в процесі плавки формується стовпчаста структура кристалітів, що забезпечує разом з очищенням зразків в результаті зонної перекристалізації підвищення рівня питомого електроопору зливків