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J E Pool

Publications and source records attributed to J E Pool.

3 recordsLinked to original sources

Finding of male-killing Spiroplasma infecting Drosophila melanogaster in Africa implies transatlantic migration of this endosymbiont.

We report the identification of male-killing Spiroplasma in a wild-caught female Drosophila melanogaster from Uganda, the first such infection to be found in this species outside of South America. Among 38 female flies collected from Namulonge, Uganda in April, 2005, one produced a total of 41 female offspring but no males. PCR testing of subsequent generations revealed that females retaining Spiroplasma infection continued to produce a large excess of female progeny, while females that had lost Spiroplasma produced offspring with normal sex ratios. Consistent with earlier work, we find that male-killing and transmission efficiency appear to increase with female age, and we note that males born in sex ratio broods display much lower survivorship than their female siblings. DNA sequence comparisons at three loci suggest that this Spiroplasma strain is closely related to the male-killing strain previously found to infect D. melanogaster in Brazil, although part of one locus appears to show a recombinant history. Implications for the origin and history of male-killing Spiroplasma in D. melanogaster are discussed.

Aging↗

An experiment on cognitive remediation of word-reading difficulty.

Cognitive remediation of decoding deficit was attempted by following a theoretically based program. The theory identifies four major cognitive processes: Planning, Attention, Simultaneous, and Successive (PASS) processing. The PASS Remedial Program (PREP) provides 10 structured tasks that are aimed at developing internalized strategies for mainly successive processes (6 tasks) and simultaneous process (4 tasks); deficits in either of the two may lead to poor decoding. Through its "global process" training and curriculum-related "bridging" training, PREP facilitates application of internalized strategies arrived at inductively for learning word decoding and spelling; it does not provide direct teaching of rules or exercises. To test the efficacy of PREP, we divided 51 children with decoding difficulties in Grade 4 into two groups: PREP (both global and bridging) and no treatment. In the second part of the study, children from the no-treatment group received either the global or the bridging part of PREP. The relative efficacy of training was tested by pre-, and posttests of performance on a standard word-decoding test (the WRMT-R), as well as on some cognitive tests (e.g., the CAS). The largest improvement in word decoding occurred for the PREP combined global and bridging treatment. The mechanism through which PREP improves word reading is discussed, as is the use of PREP for children at risk of developing dyslexia.

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