1,207 research outputs found

    A biotelemetric study comparing diving behavior and brumation sites of translocated and resident northern map turtles (Graptemys geographica) and their response to replica model turtles on artificial basking/nesting platforms in the Upper Niagara River

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    Anthropogenic shoreline development leading to a lack of access to terrestrial nesting sites is one of the causes for northern map turtle decline in the upper Niagara River. Translocation of adult map turtles and the development of floating basking/nesting platforms were proposed as possible remedies for this population decline. Biotelemetry along with aerial and underwater drones were used to assess habitat preferences between resident and translocated turtles. It was expected that the platforms would be used for basking and nesting and that a platform located in a natural location would be more successful than one in a developed area, due to its close resemblance to the translocated turtles’ native habitat. The developed area platform received the most use. Map turtles did not use the platform for nesting. Comparisons were made between translocated and resident turtles’ basking behavior, depth selection, and brumation site selection. The highest number of turtles seen basking was between noon and 4 p.m. An air temperature exceeding water temperature by 9 °C frequently initiated basking behavior. Model turtles did not significantly alter basking behavior. Brumation habitats of translocated turtles was similar to that of resident turtles, with most turtles selecting sites in the river. The depths selected for brumation were similar between translocated and resident turtles. GIS modeling was used to define the areas used by the turtles. This information is being applied to conservation efforts that are currently being undertaken along the Niagara River to incorporate turtle nesting habitats in appropriate areas

    A high-order fully coupled electro-fluid-dynamics solver for multiphase flow simulations

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    A high-order discontinuous Galerkin Finite Element solver is developed for solving electro-fluid-dynamics problems. The solver is employed to perform numerical simulations of deformation of a droplet suspended in another immiscible liquid by applying steady and oscillatory electric fields. The level set method is adopted to represent the common interface of the droplet and surrounding medium. Electrostatics equation with a jump in the dielectric property at the interface is solved to find the electric field distribution. The incompressible Navier-Stokes equations including the surface tension force are solved to find the flow field. The Electrostatics and Navier-Stokes equations are coupled through changes in the geometry because of the deformation of the droplet and the dielectrophoretic body force, which is present at the interface

    Demographic and mental health assessments in the adolescent brain and cognitive development study: Updates and age-related trajectories

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    The Adolescent Brain Cognitive Development (ABCD) Study of 11,880 youth incorporates a comprehensive range of measures assessing predictors and outcomes related to mental health across childhood and adolescence in participating youth, as well as information about family mental health history. We have previously described the logic and content of the mental health assessment battery at Baseline and 1-year follow-up. Here, we describe changes to that battery and issues and clarifications that have emerged, as well as additions to the mental health battery at the 2-, 3-, 4-, and 5-year follow-ups. We capitalize on the recent release of longitudinal data for caregiver and youth report of mental health data to evaluate trajectories of dimensions of psychopathology as a function of demographic factors. For both caregiver and self-reported mental health symptoms, males showed age-related decreases in internalizing and externalizing symptoms, while females showed an increase in internalizing symptoms with age. Multiple indicators of socioeconomic status (caregiver education, family income, financial adversity, neighborhood poverty) accounted for unique variance in both caregiver and youth-reported externalizing and internalizing symptoms. These data highlight the importance of examining developmental trajectories of mental health as a function of key factors such as sex and socioeconomic environment

    When insecure attachment dispositions affect mentoring relationship quality : an exploration of interactive mentoring contexts

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    In this study, we explored the effects of mentor and mentee insecure attachment dispositions (ambivalence and avoidance) on mentoring relationship quality while considering the specific nature of the interactive mentoring context. Participants (n = 252 matches) were enrolled in the MIRES program, a one-year college-based mentoring program that matches late adolescent mentees (17-year-olds) with young adult mentors (23-year-olds) designed to facilitate the transition to college. Using data drawn from mentors’ logbooks (at 9 time points), two interactive contexts were addressed: 1) situations involving mentee academic issues and mentor proactive academic support (academically-oriented), and 2) situations involving mentee personal issues and mentor emotional support, and caring (emotionally-oriented). Linear regression results showed that both mentors’ and mentees’ avoidance uniquely predicted lower reports of mentoring relationship quality, but especially inemotionally-oriented matches and when their partners’ attachment ambivalence was high. In matches less focused on emotional support, mentors’ attachment avoidance interacted with mentees’ ambivalence to predict positive mentoring relationship quality. Theoretical, practical, and mentor training issues are discussed

    Regional vulnerability indices in youth with persistent and distressing psychoticlike experiences

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    IMPORTANCE: Distressing and persistent psychoticlike experiences (PLEs) in youth are associated with greater odds of developing psychiatric conditions in adulthood. Despite this risk, it is unclear whether early PLEs show similar brain patterns compared with adults with psychiatric and neurologic conditions. OBJECTIVE: To examine the degree to which persistent and distressing PLEs exhibit neural metrics that show similarity to adults with chronic psychiatric and neurologic conditions. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used Adolescent Brain Cognitive Development (ABCD) Study examining the persistence and distress associated with PLEs across the first 3 waves of data with baseline structural magnetic resonance imaging data. Analyzed data were collected between September 1, 2016, and September 27, 2021. Children were recruited from 21 research sites across the US. EXPOSURES: Psychoticlike experiences were assessed using the Prodromal Questionnaire-Brief Child Version, and participants were categorized into groups based on the persistence and distress associated with PLEs. MAIN OUTCOMES AND MEASURES: Cortical and subcortical regional vulnerability indices (RVIs) were created by quantifying the similarity of participants\u27 baseline neuroimaging measures to the expected patterns found in adult neuropsychiatric samples. The PLE groups were compared on the following RVI cortical and subcortical metrics: schizophrenia spectrum disorders, bipolar disorder, major depressive disorder, Parkinson disease, Alzheimer disease, and metabolic diseases. RESULTS: Analyses examined PLE groups created from 8242 children in the ABCD sample (52.5% male; mean [SD] age, 9.93 [0.63] years; and 56.3% White), including persistent distressing PLEs (n = 329), transient distressing PLEs (n = 396), persistent nondistressing PLEs (n = 234), transient nondistressing PLEs (n = 390), and low distressing PLEs (n = 6893) groups. Participants with persistent or transient distressing PLEs broadly showed increased subcortical RVI scores across most RVI metrics, with persistent distressing PLEs additionally showing increased scores for cortical RVI metrics. The greatest effect sizes were found for persistent distressing PLEs with cortical RVI-schizophrenia spectrum disorders (β estimate, 1.055; 95% CI, 0.326-1.786) and RVI-Alzheimer disease (β estimate, 2.473; 95% CI, 0.930-4.018). CONCLUSIONS AND RELEVANCE: In this cohort study of ABCD participants, the findings suggest that especially the persistent distressing PLEs in children were associated with neural metrics resembling those observed in adults with severe psychiatric and neurologic conditions. These findings support the potential use of brain-based risk scores for early identification and precision medicine approaches in the assessment of PLEs

    Stability of bicontinuous cubic phases in ternary amphiphilic systems with spontaneous curvature

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    We study the phase behavior of ternary amphiphilic systems in the framework of a curvature model with non-vanishing spontaneous curvature. The amphiphilic monolayers can arrange in different ways to form micellar, hexagonal, lamellar and various bicontinuous cubic phases. For the latter case we consider both single structures (one monolayer) and double structures (two monolayers). Their interfaces are modeled by the triply periodic surfaces of constant mean curvature of the families G, D, P, C(P), I-WP and F-RD. The stability of the different bicontinuous cubic phases can be explained by the way in which their universal geometrical properties conspire with the concentration constraints. For vanishing saddle-splay modulus κˉ\bar \kappa, almost every phase considered has some region of stability in the Gibbs triangle. Although bicontinuous cubic phases are suppressed by sufficiently negative values of the saddle-splay modulus κˉ\bar \kappa, we find that they can exist for considerably lower values than obtained previously. The most stable bicontinuous cubic phases with decreasing κˉ<0\bar \kappa < 0 are the single and double gyroid structures since they combine favorable topological properties with extreme volume fractions.Comment: Revtex, 23 pages with 10 Postscript files included, to appear in J. Chem. Phys. 112 (6) (February 2000

    Influence of keel impacts and laying hen behavior on keel bone damage.

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    Keel bone damage, which presents as fractures and/or deviations of the keel, has been detected in laying hens housed in all types of systems. Factors leading to keel bone damage in hens housed with limited vertical space, such as those housed in furnished systems, are not well understood, and are the topic of this study. Ten focal hens from each of 12 furnished cages (4 rooms of 3 cages) were fitted with keel mounted tri-axial accelerometers. Their behavior was video recorded continuously over two 3-wk trials: the first when the hens were between 52 and 60 wk of age, and the second approximately 20 wk later. The integrity of each hen's keel was evaluated at the start and end of each 3-wk trial using digital computed tomography. We identified predominant behaviors associated with acceleration events sustained at the keel (collisions, aggressive interactions and grooming) by pairing accelerometer outputs with video data. For each recorded acceleration event we calculated the acceleration magnitudes as the maximum summed acceleration recorded during the event, and by calculating the area under the acceleration curve. A principle components analysis, which was used as a data reduction technique, resulted in the identification of 4 components that were used in a subsequent regression analysis. A key finding is that the number of collisions a hen has with structures in her environment, and the number of aggressive interactions that a hen is involved, each affect the likelihood that she will develop 1 or more fractures within a 3-wk time span. This relationship between hen behavior and keel fracture formation was independent of the magnitude of acceleration involved in the event. Observed behavior did not have an impact on the formation of keel bone deviations, further supporting reports that the mechanisms underlying the 2 types of keel bone damage are different

    Mid-latitude tropospheric ozone columns from the MOZAIC program: climatology and interannual variability

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    Several thousands of ozone vertical profiles collected in the course of the MOZAIC programme (Measurements of Ozone, Water Vapour, Carbon Monoxide and Nitrogen Oxides by In-Service Airbus Aircraft) from August 1994 to February 2002 are investigated to bring out climatological and interannual variability aspects. The study is centred on the most frequently visited MOZAIC airports, i.e. Frankfurt (Germany), Paris (France), New York (USA) and the cluster of Tokyo, Nagoya and Osaka (Japan). The analysis focuses on the vertical integration of ozone from the ground to the dynamical tropopause and the vertical integration of stratospheric-origin ozone throughout the troposphere. The characteristics of the MOZAIC profiles: frequency of flights, accuracy, precision, and depth of the troposphere observed, are presented. The climatological analysis shows that the Tropospheric Ozone Column (<I>TOC</I>) seasonal cycle ranges from a wintertime minimum at all four stations to a spring-summer maximum in Frankfurt, Paris, and New York. Over Japan, the maximum occurs in spring presumably because of the earlier springtime sun. The incursion of monsoon air masses into the boundary layer and into the mid troposphere then steeply diminishes the summertime value. Boundary layer contributions to the <I>TOC</I> are 10% higher in New York than in Frankfurt and Paris during spring and summer, and are 10% higher in Japan than in New York, Frankfurt and Paris during autumn and early spring. Local and remote anthropogenic emissions, and biomass burning over upstream regions of Asia may be responsible for the larger low- and mid-tropospheric contributions to the tropospheric ozone column over Japan throughout the year except during the summer-monsoon season. A simple Lagrangian analysis has shown that a minimum of 10% of the <I>TOC</I> is of stratospheric-origin throughout the year. Investigation of the short-term trends of the <I>TOC</I> over the period 1995&ndash;2001 shows a linear increase 0.7%/year in Frankfurt, 0.8%/year in Japan, 1.1%/year in New York and 1.6%/year in Paris for the reduced 1995&ndash;1999 period. Dominant ingredients of these positive short-term trends are the continuous increase of wintertime tropospheric ozone columns from 1996 to 1999 and the positive contributions of the mid troposphere whatever the season
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