Stay at home aphids: comparative spatial and seasonal metapopulation structure and dynamics of two specialist tansy aphid species studied using microsatellite markers

The structure and dynamics of races of the potato late blight pathogen Phytophthora infestans in several populations collected worldwide during 1966–1993 were investigated using mathematical estimates of phenotypic diversity (Shannon and Rogers indices) and of virulence complexity. As expected, the highest diversity of races was found in central Mexico, whereas European and other American populations had consistently lower numbers of races and were usually dominated by one or a few phenotypes. Rogers indices were generally close to 0.5 when calculated for populations collected over successive years from the same area and for populations from neighbouring regions collected at the same period of time, indicating that some geographical and temporal structuring was the rule. This is consistent with a metapopulation structure for P. infestans and provides evidence for evolutionary patterns driven by founder effects. The mean number of virulence genes per race was highly variable among populations. Unnecessary virulences were frequent in most if not all populations. In all populations investigated, the rarest virulence genes were found in highly complex races, indicating a predominant influence of mutation events on race evolution. Key words: potato, late blight, virulence, diversity, complexity, population structure.

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Difference in metapopulation structure and dynamics of two species of coexistent melitaeine butterflies

Chinese Science Bulletin ◽

10.1360/03wc0008 ◽

2003 ◽

Vol 48 (12) ◽

pp. 1239 ◽

Cited By ~ 1

Author(s):

Yifei WANG

Keyword(s):

Structure And Dynamics ◽

Metapopulation Structure

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Siblings of Children with Mental Retardation Living at Home or in Residential Placement

Journal of Child Psychology and Psychiatry ◽

10.1017/s0021963097002084 ◽

1998 ◽

Vol 39 (3) ◽

pp. 355-363 ◽

Cited By ~ 36

Author(s):

Laurie Eisenberg ◽

Bruce L. Baker ◽

Jan Blacher

Keyword(s):

Mental Retardation ◽

Residential Placement ◽

At Home

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Nucleosome dynamics

Biochemical Society Symposium ◽

10.1042/bss0730109 ◽

2006 ◽

Vol 73 ◽

pp. 109-119 ◽

Cited By ~ 2

Author(s):

Chris Stockdale ◽

Michael Bruno ◽

Helder Ferreira ◽

Elisa Garcia-Wilson ◽

Nicola Wiechens ◽

...

Keyword(s):

High Resolution ◽

Chromatin Structure ◽

Current Knowledge ◽

Dynamic Properties ◽

Structure And Dynamics ◽

Nucleosome Dynamics ◽

Sharp Focus ◽

Recent Advances ◽

Insight Into ◽

Chromatin Structure And Dynamics

In the 30 years since the discovery of the nucleosome, our picture of it has come into sharp focus. The recent high-resolution structures have provided a wealth of insight into the function of the nucleosome, but they are inherently static. Our current knowledge of how nucleosomes can be reconfigured dynamically is at a much earlier stage. Here, recent advances in the understanding of chromatin structure and dynamics are highlighted. The ways in which different modes of nucleosome reconfiguration are likely to influence each other are discussed, and some of the factors likely to regulate the dynamic properties of nucleosomes are considered.

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Systematic Modification of Parental Input to Train Language Symbols

Language Speech and Hearing Services in Schools ◽

10.1044/0161-1461.1201.04 ◽

1981 ◽

Vol 12 (1) ◽

pp. 4-12 ◽

Cited By ~ 6

Author(s):

Barbara Culatta ◽

Donna Horn

Keyword(s):

Language Learning ◽

Meaningful Use ◽

Hearing Impaired ◽

Specific Language ◽

Parental Input ◽

Language Exposure ◽

Therapy Sessions ◽

Impaired Children ◽

Hearing Impaired Children ◽

At Home

This study attempted to maximize environmental language learning for four hearing-impaired children. The children's mothers were systematically trained to present specific language symbols to their children at home. An increase in meaningful use of these words was observed during therapy sessions. In addition, as the mothers began to generalize the language exposure strategies, an increase was observed in the children's use of words not specifically identified by the clinician as targets.

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Iterative Development of a Home Review Program to Promote Preschoolers' Vocabulary Skills: Social Validity and Learning Outcomes

Language Speech and Hearing Services in Schools ◽

10.1044/2019_lshss-19-00011 ◽

2020 ◽

Vol 51 (2) ◽

pp. 371-389 ◽

Cited By ~ 2

Author(s):

Xigrid Soto ◽

Yagmur Seven ◽

Meaghan McKenna ◽

Keri Madsen ◽

Lindsey Peters-Sanders ◽

...

Keyword(s):

High Stress ◽

Social Validity ◽

Home Language ◽

Single Subject ◽

Considerable Difficulty ◽

Home Program ◽

Iterative Development ◽

Vocabulary Skills ◽

Validity Measures ◽

At Home

Purpose This article describes the iterative development of a home review program designed to augment vocabulary instruction for young children (ages 4 and 5 years) occurring at school through the use of a home review component. Method A pilot study followed by two experiments used adapted alternating treatment designs to compare the learning of academic words taught at school to words taught at school and reviewed at home. At school, children in small groups were taught academic words embedded in prerecorded storybooks for 6 weeks. Children were given materials such as stickers with review prompts (e.g., “Tell me what brave means”) to take home for half the words. Across iterations of the home intervention, the home review component was enhanced by promoting parent engagement and buy-in through in-person training, video modeling, and daily text message reminders. Visual analyses of single-subject graphs, multilevel modeling, and social validity measures were used to evaluate the additive effects and feasibility of the home review component. Results Social validity results informed each iteration of the home program. The effects of the home program across sites were mixed, with only one site showing consistently strong effects. Superior learning was evident in the school + home review condition for families that reviewed words frequently at home. Although the home review program was effective in improving the vocabulary skills of many children, some families had considerable difficulty practicing vocabulary words. Conclusion These studies highlight the importance of using social validity measures to inform iterative development of home interventions that promote feasible strategies for enhancing the home language environment. Further research is needed to identify strategies that stimulate facilitators and overcome barriers to implementation, especially in high-stress homes, to enrich the home language environments of more families.

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