“How” and “Why” prompts in forensic investigative interviews with preschool children

Although young children may frequently be asked “How” and “Why” questions, it is unclear whether they have the ability to respond well enough to justify the use of these words during investigative interviews. The range of possible uses and interpretations of the words “How” and “Why” makes it critical to examine their use when communicatively immature children are interviewed. In this study, police interviews of 3- to 5-year-old suspected victims of sexual abuse (n = 49) were examined. The use of How/Why prompts by interviewers and children’s responses to interviewers’ How/Why prompts were coded. How/Why prompts represented 22% of all interviewer prompts. Of all details provided by children, however, 8.5% were in response to How/Why prompts. In addition, children provided the information sought in response to only 20% of the interviewers’ How/Why prompts, whereas uninformative responses were relatively common. Children responded to more How/Why prompts with the information sought by interviewers as they grew older. The findings suggest that How/Why prompts may not be particularly effective when interviewing preschool children.     

Construction and Characterization of aMagnaporthe griseaBacterial Artificial Chromosome Library

Diaz-Perez, S. V., Crouch, V. W., and Orbach, M. J. 1996. Construction and characterization of aMagnaporthe griseabacterial artificial chromosome library.Fungal Genet. Biol.20,280–288. A bacterial artificial chromosome (BAC) library ofMagnaporthe griseacontaining 4128 clones with an average insert size of 66-kb has been constructed. This library represents seven genome equivalents ofM. griseaand has been demonstrated to be representative of the genome by screening for the presence of several single-copy genes and DNA markers. The utility of the library for use in map-based cloning projects was shown by the spanning of a nine-cosmid, 207-kb DNA contig with only 3 BAC clones. In addition, using alys1-3auxotroph, we have shown that BAC clones at least 113 kb can be transformed intoM. griseato screen for complementation of mutations. Thus, BACs isolated in chromosome walks can be rapidly screened for the presence of the sought after gene. The ease of construction of BAC libraries and of isolation and manipulation of BAC clones makes the BAC system an ideal one for physical analyses of fungal genomes.     

Towards a comprehensive barcode library for arctic life - Ephemeroptera, Plecoptera, and Trichoptera of Churchill, Manitoba, Canada

Background

In order to understand the role of herbivores in trophic webs, it is essential to know what they feed on. Diet analysis is, however, a challenge in many small herbivores with a secretive life style. In this paper, we compare novel (high-throughput pyrosequencing) DNA barcoding technology for plant mixture with traditional microhistological method. We analysed stomach contents of two ecologically important subarctic vole species, Microtus oeconomus and Myodes rufocanus, with the two methods. DNA barcoding was conducted using the P6-loop of the chloroplast trnL (UAA) intron.

Results

Although the identified plant taxa in the diets matched relatively well between the two methods, DNA barcoding gave by far taxonomically more detailed results. Quantitative comparison of results was difficult, mainly due to low taxonomic resolution of the microhistological method, which also in part explained discrepancies between the methods. Other discrepancies were likely due to biases mostly in the microhistological analysis.

Conclusion

We conclude that DNA barcoding opens up for new possibilities in the study of plant-herbivore interactions, giving a detailed and relatively unbiased picture of food utilization of herbivores.     

The evolution of genital shape variation in female cetaceans*

Male genital diversification is likely the result of sexual selection. Female genital diversification may also result from sexual selection, although it is less well studied and understood. Female genitalia are complex among whales, dolphins, and porpoises, especially compared to other vertebrates. The evolutionary factors affecting the diversity of vaginal complexity could include ontogeny, allometry, phylogeny, sexual selection, and natural selection. We quantified shape variation in female genitalia using 2D geometric morphometric analysis, and validated the application of this method to study soft tissues. We explored patterns of variation in the shape of the cervix and vagina of 24 cetacean species (n = 61 specimens), and found that genital shape varies primarily in the relative vaginal length and overall aspect ratio of the reproductive tract. Extensive genital shape variation was partly explained by ontogenetic changes and evolutionary allometry among sexually mature cetaceans, whereas phylogenetic signal, relative testis size, and neonate size were not significantly associated with genital shape. Female genital shape is diverse and evolves rapidly even among closely related species, consistent with predictions of sexual selection models and with findings in invertebrate and vertebrate taxa. Future research exploring genital shape variation in 3D will offer new insights into evolutionary mechanisms because internal vaginal structures are variable and can form complex spirals.     

Coccidioides posadasii contains a single 1,3-beta-glucan synthase gene that appears to be essential for growth

1,3-beta-Glucan synthase is responsible for the synthesis of beta-glucan, an essential cell wall structural component in most fungi. We sought to determine whether Coccidioides posadasii possesses genes homologous to known fungal FKS genes that encode the catalytic subunit of 1,3-beta-glucan synthase. A single gene, designated FKS1, was identified, and examination of its predicted protein product showed a high degree of conservation with Fks proteins from other filamentous fungi. FKS1 is expressed at similar levels in mycelia and early spherulating cultures, and expression decreases as the spherules mature. We used Agrobacterium-mediated transformation to create strains that harbor DeltaFKS1::hygB, a null allele of FKS1, and hypothesize that Fks1p function is essential, due to our inability to purify this allele away from a complementing wild-type FKS1 allele in a heterokaryotic strain. The heterokaryon appears normal with respect to growth rate and arthroconidium production; however, microscopic examination of strains with DeltaFKS1::hygB alleles revealed abnormal swelling of hyphal elements.     

Regions of microsynteny in Magnaporthe grisea and Neurospora crassa.

A bacterial artificial chromosome (BAC) clone containing 110,467 bp of genomic DNA from Magnaporthe grisea was sequenced, annotated, and compared to the genomes of Neurospora crassa, Candida albicans, and Saccharomyces cerevisiae. Twenty-six open reading frames (ORFs), involved in multiple biochemical pathways, were identified in the BAC sequence. A region of 53 kb, containing 18 of the 26 ORFs, was found to be syntenic to a portion of the N. crassa genome. Subregions of complete colinearity as well as interrupted colinearity were present. No synteny was evident with either C. albicans or S. cerevisiae. The identification of syntenic regions containing highly conserved genes across two genera that have been evolutionarily separated for approximately 200 million years elicits many biological questions as to the function and identity of these genes.     

An electrophoretic karyotype of Neurospora crassa.

A molecular karyotype of Neurospora crassa was obtained by using an alternating-field gel electrophoresis system which employs contour-clamped homogeneous electric fields. The migration of all seven N. crassa chromosomal DNAs was defined, and five of the seven molecules were separated from one another. The estimated sizes of these molecules, based on their migration relative to Schizosaccharomyces pombe chromosomal DNA molecules, are 4 to 12.6 megabases. The seven linkage groups were correlated with specific chromosomal DNA bands by hybridizing transfers of contour-clamped homogeneous electric field gels with radioactive probes specific to each linkage group. The mobilities of minichromosomal DNAs generated from translocation strains were also examined. The methods used for preparation of chromosomal DNA molecules and the conditions for their separation should be applicable to other filamentous fungi.     

Assessing the potential for post‐ejaculatory female choice in a polyandrous beach‐spawning fish

In species with limited opportunities for pre‐ejaculatory sexual selection (behavioural components), post‐ejaculatory mechanisms may provide opportunities for mate choice after gametes have been released. Recent evidence from a range of taxa has revealed that cryptic female choice (i.e., female‐mediated differential fertilization bias), through chemical cues released with or from eggs, can differentially regulate the swimming characteristics of sperm from various males and ultimately determine male fertilization success under sperm competition. We assessed the potential role that such female‐modulated chemical cues play in influencing sperm swimming characteristics in beach‐spawning capelin (Mallotus villosus), an externally fertilizing fish that mates as couples (one male and one female) or threesomes (two males and one female) with presumably limited opportunities for pre‐ejaculatory sexual selection. We assayed sperm swimming characteristics under varying doses and donor origins of egg cues and also examined the possibility of assortative mating based on body size. We found mating groups were not associated by size, larger males did not produce better quality ejaculates, and egg cues (regardless of dosage or donor identity) did not influence sperm swimming characteristics. Our findings suggest that intersexual pre‐ejaculatory sexual selection and cryptic female choice mediated by female chemical cues are poorly developed in capelin, possibly due to unique natural selection constraints on reproduction.