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This study analyzes middle school students' spontaneous mathematics-related help-seeking behavior, in view of making ecologically valid recommendations for the design of supporting tools or "help systems". Our aim was to investigate the content of students' help-seeking messages--Are there different forms of help-seeking messages and do they evolve with age? We used the archives of a French forum that provides students with free individualized help in mathematics. The data consisted of 206 messages sent by French middle school students over a period of 42 months. The constituent categories of the messages were identified. The results showed that not all middle school students use the same help-seeking "format". Compared to sixth graders, ninth graders wrote messages containing more constituent categories, i.e., they provided the online expert with more kinds of information. A detailed analysis of the categories further showed that older students' messages more often contained explicit help requests and contextual information than did younger students' messages. Thus, the messages of the oldest students (age 15) were both cognitively more understandable and socially more acceptable than those of the youngest students (age 11). The interpretation of these findings and their implications for designing help systems are discussed. (Contains 3 tables and 1 figure.)

Marine organisms show population structure at a relatively fine spatial scale, even in open habitats. The tools commonly used to assess subtle patterns of connectivity have diverse levels of resolution and can complement each other to inform on population structure. We assessed and compared the discriminatory power of genetic markers and otolith shape to reveal the population structure on evolutionary and ecological time scales of the common sole (Solea solea), living in the Eastern English Channel (EEC) stock off France and the UK. First, we genotyped fish with Single Nucleotide Polymorphisms to assess population structure at an evolutionary scale. Then, we tested for spatial segregation of the subunits using otolith shape as an integrative tracer of life history. Finally, a supervised machine learning framework was applied to genotypes and otolith phenotypes to probabilistically assign adults to subunits and assess the discriminatory power of each approach. Low but significant genetic differentiation was found among subunits. Moreover, otolith shape appeared to vary spatially, suggesting spatial population structure at fine spatial scale. However, results of the supervised discriminant analyses failed to discriminate among subunits, especially for otolith shape. We suggest that the degree of population segregation may not be strong enough to allow for robust fish assignments. Finally, this study revealed a weak yet existing metapopulation structure of common sole at the fine spatial scale of the EEC based on genotypes and otolith shape, with one subunit being more isolated. Our study argues for the use of complementary tracers to investigate marine population structure. [ABSTRACT FROM AUTHOR]

The link between students' spelling level and their text-messaging practice gives rise to numerous questions from teachers, parents and the media. A corpus of 4524 text messages produced in daily-life situations by students in sixth and seventh grade ( n = 19, 11-12 years of age) was compiled. None of the participants had ever owned or used a mobile phone before the start of the study; their text messages were collected monthly over the course of a year. The comparison between the group with mobile phones and the control group without mobile phones ( n = 30) showed no difference between the level of traditional writing at the beginning of the text-message collection and during the collection. The results showed that the correlation between the level of traditional spelling and the density of textisms was dependent upon the type of textisms (consistent/breaking with traditional code), the type of spelling (usage-based/rule-based), the grades in French class and the duration of text-messaging practice. On the whole, students who were skilled or less skilled in traditional writing at the beginning of the text-message collection remained respectively skilled or less skilled throughout the year, despite their text-messaging use (density and type of textisms). The discussion of this study's academic implications tends towards a complementarity between traditional writing and text messaging. [ABSTRACT FROM AUTHOR]

The fine scale morphological and genetic dynamics of successive waves of Anguilla anguilla glass eel recruitment was studied over a 2 year period at a southern European Mediterranean location (Camargue, France) with continuous recruitment. Using morphometric [total length ( LT), mass ( M), condition ( K) and pigmentation stage] as well as genetic (allozyme) markers, the aim was to test for the existence of temporally separated spawning groups and explore the relation between genetic variability and morphological heterogeneity of recruits. The results showed that LT, M and K varied over time, being highest from the end of summer to winter (peaking in December) and lowest in spring (lowest in April). The pigmentation stages within monthly samples were highly diverse with a heterogeneous seasonal pattern. Allozyme data showed high genetic variability values within samples, but low genetic differentiation among samples ( FST = 0·003, P < 0·05). Pairwise comparisons between samples indicated a positive correlation between genetic differentiation and difference in recruitment time (days), with a marked increase in genetic differentiation around 250 days between monthly recruitment samples. Furthermore, genetic diversity increased with the number of pigmentation stages per sample and was negatively correlated with the North Atlantic Oscillation (NAO) index during the putative year of trans-oceanic migration. No correlation, however, was found between the level of multilocus heterozygosity (MLH) and growth variables. A situation of genetic patchiness with fluctuating parental contribution can thus best explain the patterns observed, although the existence of two separate spawning periods cannot be excluded. More discriminatory and sensitive genetic markers, such as (neutral and adaptive) microsatellites, could probably provide additional insights into the most probable hypothesis explaining the population structure and recruitment heterogeneity of A. anguilla. [ABSTRACT FROM AUTHOR]

A microsatellite-enriched genomic library was constructed for the sand goby, Pomatoschistus minutus (Pallas 1770), and nine polymorphic DNA microsatellite markers of high quality were successfully optimized. Characterization of 96 individuals from the Vaccarès lagoon (France) showed moderate to high levels of polymorphism (two to 54 alleles). All the markers conformed to Hardy-Weinberg equilibrium and showed no evidence of null alleles, large allele dropout, stuttering and linkage disequilibrium between pairs of loci. These markers successfully amplify in three closely related species and can be employed to investigate population genetic structure and to clarify paternity in Pomatoschistus species. [ABSTRACT FROM AUTHOR]

European eel( Anguilla anguilla; Teleostei) is a valuable commercial species. However, over the past 25 years, the population of European eel has been declining to such a degree that major concerns have been raised for its long-term conservation. Since little information is available on the life-cycle and genetic structure of European eel, it has been difficult to evaluate the existence of any population substructuring. Molecular genetic methods contribute to a better knowledge of the demography and population structure in marine fish. In addition, management strategies and conservation goals must consider information on genetic substructuring as well as on life history patterns.The aim of the study is to provide more detailed knowledge on the genetic variability, demography and population substructuring of European eel by analysing and comparing natural and farmed individuals. Natural eel samples have been obtained in two geographical sites(Netherlands, France) including temporal samples in a short-scale(within years) and a long-scale(between years). Simultaneously, farmed glass eels have been grown in two separate batches during one year. Batches have been monitored and genetic samples have been obtained during the year.A combination of selection-sensitive(allozymes) and selection-neutral markers(microsatellites) has been used in the study since selection seems to play an important role in the determination of the quality of future eel spawners. Results suggest a positive correlation between growth and genetic variability since individuals attaining a large length and mass present significant higher heterozygosities. [ABSTRACT FROM AUTHOR]

We analyzed naturally occurring help-seeking exchanges ( n = 123) between 11th and 12th graders and mathematics teachers on a French homework help forum. The results showed that (1) most students did not adopt a self-regulated learning (SRL) attitude when approaching the teacher for the first time (i.e., they did not communicate their preliminary work on the task for which they were seeking help, and they did not formulate an explicit request for help), (2) students' SRL attitude facilitated the teacher's work, while a non-SRL attitude made the teacher's work more difficult, (3) more than one student out of four shifted from a non-SRL attitude to an SRL attitude during the help-seeking exchange, and (4) students who returned to the forum after receiving the teacher's answer typically did so in order to ask for more help. Furthermore, the classical three-part structure (i.e., opening, message, closing) of traditional social interaction was only employed by the teachers; openings and especially closings were frequently absent in the students' messages. In conclusion, the characteristics of the students' initial message seemed to determine whether the pedagogical process between the student and the teacher got off to a good start. The students' messages were different from standard written and spoken communication, tending towards abbreviated form, content, and politeness. [ABSTRACT FROM AUTHOR]