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Common Strategy Used (common + strategy_used)
Selected AbstractsSpecies diversity of lepidopteran stem borer parasitoids in cultivated and natural habitats in KenyaJOURNAL OF APPLIED ENTOMOLOGY, Issue 6 2009D. M. Mailafiya Abstract Field surveys were conducted during 2005 to 2007 to assess the species diversity of stem borer parasitoids in cultivated and natural habitats in four agroecological zones in Kenya. In total, 33 parasitoid species were recovered, of which 18 parasitized six stem borer species feeding on cereal crops, while 27 parasitized 21 stem borer species feeding on 19 wild host plant species. The most common parasitoids in cultivated habitats were Cotesia flavipes Cameron, Cotesia sesamiae (Cameron), Pediobius furvus Gahan and the tachinid Siphona sp., whereas in natural habitats, Siphona sp. was the most common. The majority of parasitoids were stenophagous species; only five species ,Cotesia sp., Enicospilus ruscus Gauld and Mitchell, Pristomerus nr. bullis, Sturmiopsis parasitica (Curran) and Syzeuctus ruberrimus Benoit , were monophagous. In both cultivated and natural habitats, parasitoid species diversity was highest on the most dominant stem borers Busseola spp. and Chilo spp. On cereal crops, parasitoid diversity was highest on maize and among wild host plants, it was highest on Setaria spp. The ingress-and-sting attack method was the most common strategy used by parasitoids in both habitats. In all agroecological zones, parasitoid species diversity was significantly higher in natural than in cultivated habitats. Furthermore, the majority of parasitoid species were common to both cultivated and natural habitats. It was concluded that natural habitats surrounding cereal crops serve as refugia for sustaining the diversity of stem borer parasitoids from adjacent cereal fields. [source] Conflict resolution in women is related to trait aggression and menstrual cycle phaseAGGRESSIVE BEHAVIOR, Issue 3 2003Alyson J. Bond Abstract Twenty-four women with a diagnosis of premenstrual dysphoric disorder (PMDD) and 18 controls took part in a study of patterns of female aggression. They completed a version of the Conflict Tactics Scale for a premenstrual and a follicular phase of their menstrual cycle and for the past year. The Life History of Aggression was completed during a clinician interview. The women used more aggressive tactics to solve conflicts in the premenstrual than in the follicular phase, but the difference was only significant for the PMDD group. During the past year, reasoning was the most common strategy used by women to resolve conflicts, but verbal aggression was also prevalent. Although physical violence was less common, the prevalence of any act of violence was 33% in the controls and 62% in the clinical group. Women with PMDD used both verbal and physical aggression more frequently than the controls and had a higher lifetime history of aggression. Aggression by women toward partners was associated with a general tendency to act aggressively. Aggr. Behav. 29:228,238, 2003. © 2003 Wiley-Liss, Inc. [source] Heterochromatin-mediated control of virulence gene expressionMOLECULAR MICROBIOLOGY, Issue 3 2006Catherine J. Merrick Summary In recent years, the sequencing and annotation of complete genomes, together with the development of genetic and proteomic techniques to study previously intractable eukaryotic microbes, has revealed interesting new themes in the control of virulence gene expression. Families of variantly expressed genes are found adjacent to telomeres in the genomes of both pathogenic and non-pathogenic organisms. This subtelomeric DNA is normally heterochromatic and higher-order chromatin structure has now come to be recognized as an important factor controlling both the evolution and expression dynamics of these multigene families. In eukaryotic cells, higher-order chromatin structure plays a central role in many DNA processes including the control of chromosome integrity and recombination, DNA partitioning during cell division, and transcriptional control. DNA can be packaged in two distinct forms: euchromatin is relatively accessible to DNA binding proteins and generally contains active genes, while heterochromatin is densely packaged, relatively inaccessible and usually transcriptionally silent. These features of chromatin are epigenetically inherited from cell cycle to cell cycle. This review will focus on the epigenetic mechanisms used to control expression of virulence genes in medically important microbial pathogens. Examples of such control have now been reported in several evolutionarily distant species, revealing what may be a common strategy used to regulate many very different families of genes. [source] Improving the precision of cotton performance trials conducted on highly variable soils of the southeastern USA coastal plainPLANT BREEDING, Issue 6 2007B. T. Campbell Abstract Reliable agronomic and fibre quality data generated in Upland cotton (Gossypium hirsutum L.) cultivar performance trials are highly valuable. The most common strategy used to generate reliable performance trial data uses experimental design to minimize experimental error resulting from spatial variability. However, an alternative strategy uses a posteriori statistical procedures to account for spatial variability. In this study, the efficiency of the randomized complete block (RCB) design and nearest neighbour adjustment (NNA) were compared in a series of cotton performance trials conducted in the southeastern USA to identify the efficiency of each in minimizing experimental error for yield, yield components and fibre quality. In comparison to the RCB, relative efficiency of the NNA procedure varied amongst traits and trials. Results show that experimental analyses, depending on the trait and selection intensity employed, can affect cultivar or experimental line selections. Based on this study, we recommend researchers conducting cotton performance trials on variable soils consider using NNA or other spatial methods to improve trial precision. [source] | ||||||||||