1,384 research outputs found
Feasibility of stocking grass carp (Ctenopharyngodon idella; Cyprinidae) to control hydrilla (Hydrilla verticillata; Hydrocharitaceae) in Lake Anna, Virginia
The goal of this study was to demonstrate the feasibility of using triploid ·Ctenopharvngodon idella (grass carp) to control Hydrilla verticillata in the Waste Heat Treatment Facility (WHTF) in Lake Anna, Virginia. The four objectives were to determine: the frequency of occurrences of grass carp over hydrilla; the proportions of hydrilla to other aquatic macrophytes in the guts of grass carp; effects of physical and chemical factors on movement of grass carp; and a theoretical stocking rate of grass carp for the WHTF. Frequency of occurrence of grass carp over hydrilla was calculated to be 84% and correlated with impoundment size. The proportion of hydrilla in the guts of two adult triploid grass carp captured from Lake Anna averaged 88%. Physical and chemical factors had no significant effects on movements of triploid grass carp. There were no statistical correlations between fish movement and final location to water chemistry and presence/absence of hydrilla and other macrophytes. A theoretical stocking rate of grass carp to control the approximate biomass of hydrilla in the WHTF was calculated to be 6, 134 fish. This theoretical stocking rate is consistent with the stocking rate employed by the Department of Game and Inland Fisheries of seven fish per acre of infestation or approximately 6,800 grass carp to control hydrilla in the WHTF in Lake Anna, Virginia
Individual Differences in Performance Speed Are Associated With a Positivity/Negativity Bias. An ERP and Behavioral Study
There is a current dispute over the origins, incidence, and development of Positivity Bias, i.e., preferential processing of positive relative to negative information. We addressed this question using a multi-method technique of behavioral, psychometric and event-related potential (ERP) measures in a lexical decision task (LDT). Twenty-four university students (11 female) participated (age range 18–26), but four were omitted owing to data issues. Participants were classified as Positivity Biased (PB) if their LDT responses to positive words were faster than negative words, and vice versa for those classified as Negativity Biased (NB), leading to a group of 11 PB participants and a group of 9 NB participants. Interestingly, the PB group was significantly faster overall than the NB group and had significantly shorter P2 component ERP latencies in the left occipital region. Furthermore, the PB group had significantly higher scores for expressive suppression (ES), together with higher scores for Crystallized Knowledge and for cognitive reappraisal (CR). These results suggest that around 55% of the students had Positivity Bias, and these were more efficient in processing information and had better emotion regulation abilities than those with a Negativity Bias
The roles of impulsivity, self-regulation, and emotion regulation in the experience of self-disgust
Self-disgust is a distinct self-conscious emotion schema that is characterized by disgust appraisals directed towards the self. Recent studies have demonstrated an association between self-disgust and a range of psychological disorders, but there is a paucity of research on the psychological phenomena and processes that may elicit self-disgust experiences. The present study assessed the direct and indirect effects of impulsivity, self-regulation, and emotion regulation on self-disgust. Overall, 294 participants (M age = 21.84 years, SD = 4.56) completed structured and anonymous measures of trait impulsivity, self-regulation, emotion regulation strategies, and self-disgust. Path analysis showed that non-planning impulsivity and expressive suppression (positively) and cognitive reappraisal and self-regulation (negatively) predicted self-disgust. Mediation analysis further showed that emotional regulation strategies and self-regulation mediated the association between attentional and non-planning impulsivity and self-disgust. Our findings provide, for the first time, evidence about the association between self-disgust and individual differences in impulsivity, self-regulation, and emotion regulation, and have implications for the psychological phenomena that may lead to self-disgust experiences in non-clinical populations
Self-disgust as a potential mechanism explaining the association between loneliness and depression
Background: Loneliness and self-disgust have been considered as independent predictors of
depressive symptoms. In the present study, we hypothesized that self-disgust can explain the
association between loneliness and depression, and that emotion regulation strategies interact
with self-disgust in predicting depressive symptoms.
Methods: Three hundred and seventeen participants (M = 29.29 years, SD = 14.11; 76.9%
females) completed structured anonymous self-reported measures of loneliness, self-disgust,
emotion regulation strategies, and depressive symptoms.
Results: One-way MANOVA showed that participants in the high-loneliness group reported
significantly higher behavioural and physical self-disgust, compared to those in the middle
and low-loneliness groups. Bootstrapped hierarchical linear regression analysis showed that
self-disgust significantly improved predicted variance in depressive symptoms, after
controlling for the effects of loneliness. Regression-based mediation modelling showed that
both physical and behavioural self-disgust significantly mediated the association between
loneliness and depression. Finally, moderated regression analysis showed that expressive
suppression interacted with self-disgust in predicting depressive symptoms.
Limitations: A cross-sectional design was used, and our study focused on expressive
suppression and cognitive reappraisal but not on other aspects of emotion regulation or the
modulation of emotional arousal and responses.
Conclusions: We demonstrated, for the first time, that self-disgust plays an important role in
the association between loneliness and depressive symptoms. Furthermore, variations in
emotion regulation strategies can explain the association between self-disgust and depressive
symptoms
Genetic susceptibility to allergic bronchopulmonary aspergillosis in asthma: a genetic association study
Background: In patients with asthma, the fungus Aspergillus fumigatus can cause allergic bronchopulmonary aspergillosis (ABPA). Familial ABPA is reported, and some genetic factors have been associated with the disease, however, these are small studies (n ≤ 38) and do not explain all cases of ABPA.Methods: We analysed SNPs in 95 ABPA patients, comparing frequencies to 152 atopic asthmatic and 279 healthy controls. Twenty two genes were selected from literature, and 195 tagging SNPs were analysed for genetic association with ABPA using logistic regression corrected for multiple testing. We also analysed monocyte-derived macrophage gene expression before and during co-culture with A. fumigatus.Results: Seventeen ABPA-associated SNPs (ABPA v Atopic asthma) were identified. Three remained significant after correction for multiple testing; IL13 rs20541, IL4R rs3024656, TLR3 rs1879026. We also identified minor differences in macrophage gene expression responses in the ABPA group compared to the control groups.Conclusions: Multiple SNPs are now associated with ABPA. Some are novel associations. These associations implicate cytokine pathways and receptors in the aberrant response to A. fumigatus and susceptibility to ABPA, providing insights into the pathogenesis of ABPA and/or its complications. We hope these results will lead to increased understanding and improved treatment and diagnostics for ABPA
Asymmetric localisation of Miranda and its cargo proteins during neuroblast division requires the anaphase-promoting complex/cyclosome
Asymmetric cell divisions generate cell fate diversity during both invertebrate and vertebrate development. Drosophila neural progenitors or neuroblasts (NBs) each divide asymmetrically to produce a larger neuroblast and a smaller ganglion mother cell (GMC). The asymmetric localisation of neural cell fate determinants and their adapter proteins to the neuroblast cortex during mitosis facilitates their preferential segregation to the GMC upon cytokinesis. In this study we report a novel role for the anaphase-promoting complex/cyclosome (APC/C) during this process. Attenuation of APC/C activity disrupts the asymmetric localisation of the adapter protein Miranda and its associated cargo proteins Staufen, Prospero and Brat, but not other components of the asymmetric division machinery. We demonstrate that Miranda is ubiquitylated via its C-terminal domain; removal of this domain disrupts Miranda localisation and replacement of this domain with a ubiquitin moiety restores normal asymmetric Miranda localisation. Our results demonstrate that APC/C activity and ubiquitylation of Miranda are required for the asymmetric localisation of Miranda and its cargo proteins to the NB cortex
A mosaic genetic screen for novel mutations affecting Drosophila neuroblast divisions
BACKGROUND: The asymmetric segregation of determinants during cell division is a fundamental mechanism for generating cell fate diversity during development. In Drosophila, neural precursors (neuroblasts) divide in a stem cell-like manner generating a larger apical neuroblast and a smaller basal ganglion mother cell. The cell fate determinant Prospero and its adapter protein Miranda are asymmetrically localized to the basal cortex of the dividing neuroblast and segregated into the GMC upon cytokinesis. Previous screens to identify components of the asymmetric division machinery have concentrated on embryonic phenotypes. However, such screens are reaching saturation and are limited in that the maternal contribution of many genes can mask the effects of zygotic loss of function, and other approaches will be necessary to identify further genes involved in neuroblast asymmetric division. RESULTS: We have performed a genetic screen in the third instar larval brain using the basal localization of Miranda as a marker for neuroblast asymmetry. In addition to the examination of pupal lethal mutations, we have employed the MARCM (Mosaic Analysis with a Repressible Cell Marker) system to generate postembryonic clones of mutations with an early lethal phase. We have screened a total of 2,300 mutagenized chromosomes and isolated alleles affecting cell fate, the localization of basal determinants or the orientation of the mitotic spindle. We have also identified a number of complementation groups exhibiting defects in cell cycle progression and cytokinesis, including both novel genes and new alleles of known components of these processes. CONCLUSION: We have identified four mutations which affect the process of neuroblast asymmetric division. One of these, mapping to the imaginal discs arrested locus, suggests a novel role for the anaphase promoting complex/cyclosome (APC/C) in the targeting of determinants to the basal cortex. The identification and analysis of the remaining mutations will further advance our understanding of the process of asymmetric cell division. We have also isolated a number of mutations affecting cell division which will complement the functional genomics approaches to this process being employed by other laboratories. Taken together, these results demonstrate the value of mosaic screens in the identification of genes involved in neuroblast division
Prosthesis use is associated with reduced physical self-disgust in limb amputees
Self-disgust is an emotion schema negatively affecting people’s body image and is triggered by bodily imperfections and deviations from the “normal” body envelope. In this study, we explore the idea that “normalising” the body in those with limb amputations via the prosthesis would be linked to reduced self-directed disgust. An international clinical community sample (N = 83) with mostly lower limb amputations completed measures about their demographics, prosthesis, adjustment, body image disturbance, psychological distress, and self-directed disgust in a survey design. Consistent with the “normalising” hypothesis, correlation and bootstrapped regression models revealed, first, that frequency of prosthesis use was significantly and negatively associated with physical self-disgust. Second, prosthesis use significantly mediated the exogenous effect of time since amputation on physical self-disgust. These results emphasise the psychological value of the prosthesis beyond its functional use, and stress its importance in normalising the body envelope in those with limb amputations, which may in turn promote psychological well-being
Immunogenicity and safety of three consecutive production lots of the non replicating smallpox vaccine MVA: A randomised, double blind, placebo controlled phase III trial
<div><p>Background</p><p>Modified Vaccinia Ankara (MVA) is a live, viral vaccine under advanced development as a non-replicating smallpox vaccine. A randomised, double-blind, placebo-controlled phase III clinical trial was conducted to demonstrate the humoral immunogenic equivalence of three consecutively manufactured MVA production lots, and to confirm the safety and tolerability of MVA focusing on cardiac readouts.</p><p>Methods</p><p>The trial was conducted at 34 sites in the US. Vaccinia-naïve adults aged 18-40 years were randomly allocated to one of four groups using a 1:1:1:1 randomization scheme. Subjects received either two MVA injections from three consecutive lots (Groups 1-3), or two placebo injections (Group 4), four weeks apart. Everyone except personnel involved in vaccine handling and administration was blinded to treatment. Safety assessment focused on cardiac monitoring throughout the trial. Vaccinia-specific antibody titers were measured using a Plaque Reduction Neutralization Test (PRNT) and an Enzyme-Linked Immunosorbent Assay (ELISA). The primary immunogenicity endpoint was Geometric Mean Titers (GMTs) after two MVA vaccinations measured by PRNT at trial visit 4. This trial is registered with ClinicalTrials.gov, number NCT01144637.</p><p>Results</p><p>Between March 2013 and May 2014, 4005 subjects were enrolled and received at least one injection of MVA (n = 3003) or placebo (n = 1002). The three MVA lots induced equivalent antibody titers two weeks after the second vaccination, with seroconversion rates of 99·8% (PRNT) and 99·7% (ELISA). Overall, 180 (6·0%) subjects receiving MVA and 29 (2·9%) subjects in the placebo group reported at least one unsolicited Adverse Event (AE) that was considered trial-related. Vaccination was well tolerated without significant safety concerns, particularly regarding cardiac assessment.</p><p>Conclusions</p><p>The neutralizing and total antibody titers induced by each of the three lots were equivalent. No significant safety concerns emerged in this healthy trial population, especially regarding cardiac safety, thus confirming the excellent safety and tolerability profile of MVA.</p><p>Trial registration</p><p>ClinicalTrials.gov <a href="https://clinicaltrials.gov/ct2/show/NCT01144637" target="_blank">NCT01144637</a></p></div
- …