The Role of Developmental Plasticity in Response to Salinity on the Evolution of Alternative Reproductive Tactics in the Sailfin Molly, Poecilia Latipinna (Poeciliidae: Poecilia: Mollienesia)

Variability in life history and morphology across conspecific populations is a widespread phenomenon and may be attributed to life history trade-offs in response to environmental variation. Such trade-offs between growth, maintenance, and reproduction often occur via developmental plasticity, which allows organisms to shift their developmental trajectories to maximize fitness in a given environment. Sailfin mollies (Poecilia latipinna) exhibit interpopulation variation in life history and morphological traits, and inhabit springs, tidal creeks, and estuaries that range from freshwater to seawater. Male size at maturity is smaller on average in freshwater springs than in brackish water marshes where these fish are most abundant. Such variation influences male fitness, because male size is fixed at maturity, highly variable, and correlated with the expression of alternative reproductive tactics. Large males erect an exaggerated dorsal sailfin in courtship displays, whereas small males perform sneaking mating behavior. In order to determine if developmental plasticity plays a role in interpopulation variation and the maintenance of size-associated mating tactics, I used a split brood design to rear siblings in low salinity (2 ppt) and brackish water (20 ppt) until sexual maturity. I found that growth and maturation rates of males and females did not differ in response to salinity. Mortality rate was somewhat higher in 20 ppt relative to 2 ppt. Females were smaller at maturity in brackish water, though their body condition did not differ in response to salinity treatment. Males also responded plastically to salinity environment, though the direction and magnitude depended largely on family genotype. Males exhibited better body condition in 20 than 2 ppt. The relative size (to body area) of the sexual ornament (dorsal sailfin) was smaller for males reared in low salinity than brackish water, suggesting that males in brackish water could allocate more energy resources towards producing larger sexual ornaments. Because males produce smallersexual ornaments and have reduced body condition in low salinity, small male body size and sneaking mating tactics may be favored in freshwater populations. Such a shift in the balance between natural and sexual selection between salinity environments may help to explain interpopulation variation in P. latipinna

Exploring the Overlap Between Dyslexia and Speech Sound Production Deficits

Purpose Children with dyslexia have speech production deficits in a variety of spoken language contexts. In this article, we discuss the nature of speech production errors in children with dyslexia, including those who have a history of speech sound disorder and those who do not, to familiarize speech-language pathologists with speech production-specific risk factors that may help predict or identify dyslexia in young children. Method In this tutorial, we discuss the role of a phonological deficit in children with dyslexia and how this may manifest as speech production errors, sometimes in conjunction with a speech sound disorder but sometimes not. We also briefly review other factors outside the realm of phonology that may alert the speech-language pathologist to possible dyslexia. Results Speech-language pathologists possess unique knowledge that directly contributes to the identification and remediation of children with dyslexia. We present several clinical recommendations related to speech production deficits in children with dyslexia. We also review what is known about how and when children with speech sound disorder are most at risk for dyslexia. Conclusion Speech-language pathologists have a unique opportunity to assist in the identification of young children who are at risk for dyslexia

Understanding the Relationships Among Students\u27 Goal Orientations, Self-Efficacy, Anxiety, and Accelerated Academic Success in the Redesign of Developmental Mathematics

The low success rates of increasing numbers of underprepared students taking developmental mathematics classes \u27often minority and economically disadvantaged\u27 are challenging community colleges across the United States. These students, who must start in the lowest levels of precollege mathematics courses, are unlikely to pass the first course and earn a credential. Using a mastery goal orientation theoretical framework, a quantitative, survey research design was used to ascertain any correlations between students\u27 goal orientations, self-efficacy, test anxiety, and success in a new model of learning. Survey data were used to answer 3 research questions: (a) the relationship between success and students\u27 perceptions of self-efficacy, goal orientation, and beliefs about test anxiety; (b) the relationship between demographics and students\u27 perceptions of self-efficacy, goal orientation, and beliefs about test anxiety; and (c) the degree to which students\u27 perceptions and experience predict success. Approximately 500 new students in the course were invited; 36 participated. Spearman\u27s rho, chi-square, and ANOVA were used to answer the research questions. Based on Spearman\u27s rho correlations, there were statistically significant relationships between self-efficacy and success as well as between intrinsic goal orientation and success. However, the sample size limited the generalizability of the findings. Further, there were no significant predictors of success. The white paper developed from this project study is intended to guide the development and expansion of accelerated developmental mathematics to increase academic success, broaden career choices, and improve the long-term economic futures of disadvantaged students enrolling in college

Phonological and lexical influences on phonological awareness in children with specific language impairment and dyslexia

Children with dyslexia and/or specific language impairment have marked deficits in phonological processing, putting them at an increased risk for reading deficits. The current study sought to examine the influence of word-level phonological and lexical characteristics on phonological awareness. Children with dyslexia and/or specific language impairment were tested using a phoneme deletion task in which stimuli differed orthogonally by sound similarity and neighborhood density. Phonological and lexical factors influenced performance differently across groups. Children with dyslexia appeared to have a more immature and aberrant pattern of phonological and lexical influence (e.g., favoring sparse and similar features). Children with SLI performed less well than children who were typically developing, but followed a similar pattern of performance (e.g., favoring dense and dissimilar features). Collectively, our results point to both quantitative and qualitative differences in lexical organization and phonological representations in children with SLI and in children with dyslexia

Water Quality Regulation

While many of the water issues in New Mexico center around having an adequate supply of water, the quality of the water is just as important as the quantity in supplying water for drinking and other uses that rely on clean water. Protecting water quality is financially more feasible than conducting expensive cleanup programs. New Mexico has a strong interest in water quality regulation to protect public health and the environment and to minimize expenditures for mitigation of contaminated supplies. Water quality is a difficult subject to navigate; there is a complex web of statutes and agency involvement. This paper is intended to be a quick reference guide to an extremely complex topic

Getting Under the Hood: How and for Whom Does Increasing Course Structure Work?

The authors explore the transferability of an active-learning intervention and expand upon the original studies by 1) disaggregating student populations to identify for whom the intervention works best and 2) exploring possible proximate mechanisms (changes in student behaviors and perceptions) that could mediate the observed increase in achievement.At the college level, the effectiveness of active-learning interventions is typically measured at the broadest scales: the achievement or retention of all students in a course. Coarse-grained measures like these cannot inform instructors about an intervention's relative effectiveness for the different student populations in their classrooms or about the proximate factors responsible for the observed changes in student achievement. In this study, we disaggregate student data by racial/ethnic groups and first-generation status to identify whether a particular intervention—increased course structure—works better for particular populations of students. We also explore possible factors that may mediate the observed changes in student achievement. We found that a “moderate-structure” intervention increased course performance for all student populations, but worked disproportionately well for black students—halving the black–white achievement gap—and first-generation students—closing the achievement gap with continuing-generation students. We also found that students consistently reported completing the assigned readings more frequently, spending more time studying for class, and feeling an increased sense of community in the moderate-structure course. These changes imply that increased course structure improves student achievement at least partially through increasing student use of distributed learning and creating a more interdependent classroom community

A longitudinal study of infants' early speech production and later letter identification

Letter identification is an early metric of reading ability that can be reliability tested before a child can decode words. We test the hypothesis that early speech production will be associated with children's later letter identification. We examined longitudinal growth in early speech production in 9 typically developing children across eight occasions, every 3 months from 9 months to 30 months. At each occasion, participants and their caregivers engaged in a speech sample in a research lab. This speech sample was transcribed for a variety of vocalizations, which were then transformed to calculate consonant-vowel ratio. Consonantvowel ratio is a measure of phonetic complexity in speech production. At the age of 72 months, children's letter knowledge was measured. A multilevel model including fixed quadratic age change and a random intercept was estimated using letter identification as a predictor of the growth in early speech production from 9±30 months, measured by the outcome of consonant-vowel ratio. Results revealed that the relation between early speech production and letter identification differed over time. For each additional letter that a child identified, their consonant-vowel ratio at the age of 9 months increased. As such, these results confirmed our hypothesis: more robust early speech production is associated with more accurate letter identification.(R01 DC006463

Seal Occurrence and Habitat Use during Summer in Petermann Fjord, Northwestern Greenland

Ice-associated seals are considered especially susceptible and are potentially the first to modify distribution and habitat use in response to physical changes associated with the changing climate. Petermann Glacier, part of a unique ice-tongue fjord environment in a rarely studied region of northwestern Greenland, lost substantial sections of its ice tongue during major 2010 and 2012 calving events. As a result, changes in seal habitat may have occurred. Seal occurrence and distribution data were collected in Petermann Fjord and adjacent Nares Strait region over 27 days (2 to 28 August) during the multidisciplinary scientific Petermann 2015 Expedition on the icebreaker Oden. During 239.4 hours of dedicated observation effort, a total of 312 individuals were recorded, representing four species: bearded seal (Erignathus barbatus), hooded seal (Crystophora cristata), harp seal (Pagophilus groenlandicus), and ringed seal (Pusa hispida). Ringed seals were recorded significantly more than the other species (χ2 = 347.4, df = 3, p < 0.001, n = 307). We found significant differences between species in haul-out (resting on ice) behavior (χ2 = 133.1, df = 3, p < 0.001, n = 307). Bearded seals were more frequently hauled out (73.1% n = 49), whereas ringed seals were almost exclusively in water (93.9%, n = 200). Differences in average depth and ice coverage where species occurred were also significant: harp seals and bearded seals were found in deeper water and areas of greater ice coverage (harp seals: 663 ± 366 m and 65 ± 14% ice cover; bearded seals: 598 ± 259 m and 50 ± 21% ice cover), while hooded seals and ringed seals were found in shallower water with lower ice coverage (hooded seals: 490 ± 163 m and 38 ± 19% ice cover; ringed seals: 496 ± 235 m, and 21 ± 20% ice cover). Our study provides an initial look at how High Arctic seals use the rapidly changing Petermann Fjord and how physical variables influence their distribution in one of the few remaining ice-tongue fjord environments.Les phoques associés aux glaces sont considérés comme très susceptibles et sont potentiellement les premiers à modifier la répartition de leur population et la façon dont ils utilisent leur habitat en réponse aux changements physiques découlant des changements climatiques. Le glacier Petermann fait partie d’une langue glaciaire de fjord unique dans une région rarement étudiée du nord-ouest du Groenland. De gros blocs de glace se sont détachés du glacier Petermann pendant le vêlage de 2010 à 2012. Par conséquent, l’habitat des phoques aurait pu être modifié. Pendant 27 jours (du 2 au 28 août), des données sur la présence et la répartition des phoques ont été recueillies au fjord Petermann et dans la région adjacente du détroit de Nares dans le cadre de l’expédition scientifique multidisciplinaire Petermann 2015 sur le brise-glace Oden. Au cours de 239,4 heures d’observation soutenue, la présence d’un total de 312 phoques représentant quatre espèces a été notée : le phoque barbu (Erignathus barbatus), le phoque à capuchon (Crystophora cristata), le phoque du Groenland (Pagophilus groenlandicus) et le phoque annelé (Pusa hispida). La présence de phoques annelés est considérablement plus importante que celle des autres espèces (χ2 = 347,4, ddl = 3, p < 0,001, n = 307). Nous avons constaté une différence significative dans les comportements d’échouerie (repos sur la glace) des phoques selon les espèces (χ2 = 133,11, ddl = 3, p < 0,001, n = 307). Les phoques barbus étaient plus souvent hors de l’eau (73,1 %, n = 49), tandis que les phoques annelés se trouvaient presque exclusivement dans l’eau (93,9 %, n = 200). Des différences significatives en ce qui a trait à la présence des espèces selon la profondeur et la couverture glaciaire ont été notées. Les phoques du Groenland et les phoques barbus fréquentent les profondeurs d’eau moyennes (663 ± 366 m et 598 ± 259 m, respectivement) et les régions où la couverture de glace correspond à la moyenne supérieure (65 ± 14 % et 50 ± 21 %, respectivement), tandis que les phoques à capuchon et les phoques annelés fréquentent les eaux moins profondes (490 ± 163 m et 496 ± 235 m, respectivement) et les régions où la couverture de glace correspond à la moyenne inférieure (38 ± 19 % et 21 ± 20, respectivement). Notre étude présente un premier aperçu de la façon dont les phoques de l’Extrême-Arctique utilisent le fjord Petermann en évolution rapide et de l’influence des variables physiques sur leur répartition dans l’une des rares langues glaciaires de fjord restantes

An Introduction to Glaciated Margins::The Sedimentary and Geophysical Archive

A glaciated margin is a continental margin that has been occupied by a large ice mass, such that glacial processes and slope processes conspire to produce a thick sedimentary record. Ice masses take an active role in sculpting, redistributing and reorganizing the sediment that they erode on the continental shelf, and act as a supply route to large fan systems (e.g. trough mouth fans, submarine fans) on the continental slope and continental rise. To many researchers, the term ‘glaciated margin’ is synonymous with modern day areas fringing Antarctica and the Arctic shelf systems, yet the geological record contains ancient examples ranging in age from Precambrian to Cenozoic. In the pre-Pleistocene record, there is a tendency for the configuration of the tectonic plates to become increasingly obscure with age. For instance, in the Neoproterozoic record, not everyone agrees on the location of rift margins and some fundamental continental boundaries remain unclear. Given these issues, this introductory paper has two simple aims: (1) to provide a brief commentary of relevant Geological Society publications on glaciated margins, with the landmark papers highlighted and (2) to explain the contents of this volume