870 research outputs found

    The Effect of Soluble Uterine Factors on Porcine Embryo Development Within a Three-Dimensional Alginate Matrix System

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    Between day 10 and 12 of gestation in the pig, the embryo undergoes a dramatic morphological change, known as elongation. During elongation the embryo produces and secretes estrogen, which serves as a key signal for maternal recognition of pregnancy. The uterine environment prepares for embryo elongation and implantation by releasing nutrients, metabolites, and hormones in a time-dependent manner relative to paracrine signals from the conceptus (i.e., estrogen) and endocrine/paracrine signals within the endometrium (i.e., progesterone). Despite advances in identification of specific uterine factors present throughout pregnancy in the pig, little is known about the exact mechanisms by which porcine embryos elongate normally, or how this elongation is altered during embryonic loss. Previously, our laboratory has established an in vitro culture system using alginate hydrogels as a three-dimensional (3-D) matrix to support the development of pre-implantation porcine embryos in base serum media without the addition of hormones. The objective of the current study was to improve our 3-D system and determine if uterine flushes from day 9 or 10 of gestation were capable of supporting in vitro embryonic development of in vivo-developed day 9 porcine embryos using the 3- D alginate culture system. Embryos collected on day 9 of gestation were assigned to be cultured in pooled day 9 flushes, day 10 flushes, or base serum media for five days within 0.7% alginate gels. Our results demonstrate that uterine flushes from day 9 or 10 of gestation supported embryonic development in our 3-D hydrogel system, similar to that from embryos cultured in base serum media. These results illustrate that soluble factors present in uterine flushings at day 9 or 10 of gestation support in vitro embryonic development within our 3-D alginate culture system. Developing better scientific understanding of the factors that regulate embryo elongation and early embryonic mortality can be useful for developing strategies to improve sow productivity and increase the profitability of swine production

    Mouse frontal cortex mediates additive multisensory decisions

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    The brain can combine auditory and visual information to localize objects. However, the cortical substrates underlying audiovisual integration remain uncertain. Here, we show that mouse frontal cortex combines auditory and visual evidence; that this combination is additive, mirroring behavior; and that it evolves with learning. We trained mice in an audiovisual localization task. Inactivating frontal cortex impaired responses to either sensory modality, while inactivating visual or parietal cortex affected only visual stimuli. Recordings from >14,000 neurons indicated that after task learning, activity in the anterior part of frontal area MOs (secondary motor cortex) additively encodes visual and auditory signals, consistent with the mice's behavioral strategy. An accumulator model applied to these sensory representations reproduced the observed choices and reaction times. These results suggest that frontal cortex adapts through learning to combine evidence across sensory cortices, providing a signal that is transformed into a binary decision by a downstream accumulator

    Metacognitive beliefs, beliefs about voices and affective symptoms in patients with severe auditory verbal hallucinations

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    Objectives. This study explores associations between metacognitive beliefs and beliefs about voices in patients with severe auditory verbal hallucinations, and their hypothesized relationship with levels of depression and anxiety. Furthermore, it was hypothesized that metacognitive beliefs are better able to explain differences in levels of depression and anxiety, than beliefs about voices. Design. Cross-sectional data were obtained from baseline measurements of a randomized controlled trial. All patients (N = 77) met the criteria for a DSM-IV diagnosis within the schizophrenia spectrum. A correlation analysis was conducted to explore the associations between metacognitive beliefs and beliefs about voices. Regression analysis was performed to test the second hypothesis. Method. Metacognitive beliefs were measured using the MCQ-30. Beliefs about voices were measured using the BAVQ-R. Furthermore, the Beck Depression Inventory-II and the Beck Anxiety Inventory were applied to measure depression and anxiety. All analyses were a priori controlled for gender and level of education. Results. Significant associations were found between negative beliefs about voices and negative metacognitive beliefs. One of the metacognitive beliefs, that is, perceived uncontrollability and danger of thinking, proved to be a key variable in explaining differences in levels of depression and anxiety and seemed to have greater explanatory value than all of the beliefs about voices when analysed simultaneously. Conclusions. The results offer modest support to models emphasizing the fact that metacognitive beliefs are a core feature in the development and maintenance of depression and anxiety in patients with severe auditory verbal hallucinations. © 2012 The British Psychological Society

    The good things children notice in nature: An extended framework for reconnecting children with nature

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    This research identifies themes emerging from a children’s writing task, where they wrote about good things they noticed in nature over a five day period. Eighty four children aged nine to eleven participated, resulting in 847 written statements. Content analysis using an emergent coding approach identified ten themes, with “Active Animals” being the most frequently occurring theme. Combining the themes with Author (2017a, b, c) pathways to nature connection provides an extended framework to inform children’s activity programmes, design of school grounds and urban spaces, aiming to connect children with nature. Future research could extend the framework into a practitioner’s tool kit.N/

    Micro-volume couette flow sample orientation for absorbance and fluorescence linear dichroism

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    Linear dichroism (LD) can be used to study the alignment of absorbing chromophores within long molecules. In particular, Couette flow LD has been used to good effect in probing ligand binding to DNA and to fibrous proteins. This technique has been previously limited by large sample requirements. Here we report the design and application of a new micro-volume Couette flow cell that significantly enhances the potential applications of flow LD spectroscopy by reducing the sample requirements for flow linear dichroism to 25 μL (with concentrations such that the absorbance maximum of the sample in a 1-cm pathlength cuvette is not, vert, similar1). The micro-volume Couette cell has also enabled the measurement of fluorescence-detected Couette flow linear dichroism. This new technique enables the orientation of fluorescent ligands to be probed even when their electronic transitions overlap with those of the macromolecule and conversely. The potential of flow-oriented fluorescence dichroism and application of the micro-volume Couette LD cell are illustrated by the collection of data for DNA with minor groove and intercalating ligands: DAPI, Hoechst, and ethidium bromide. As with conventional fluorescence, improved sensitivity compared with absorbance LD is to be expected after instrumentation optimization

    Development and initial validation of a measure of metacognitive beliefs in health anxiety: The MCQ-HA

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    Metacognitive beliefs have been shown to correlate with emotional disorders and more recently have been implicated in health anxiety. Research exploring these beliefs have tended to use the Metacognition Questionnaire (MCQ), which is a general measure. To facilitate research on the metacognitive model applied to health anxiety the present study reports on the development and initial evaluation of a new specific metacognitive measure of health anxiety, the Metacognitions Questionnaire-Health Anxiety (MCQ-HA). Principal components analysis identified 14 suitable items to be explored. Subsequent exploratory factor analysis of the MCQ-HA identified three factors: “Beliefs that Thoughts can cause Illness”, “Beliefs about Biased thinking”, and “Beliefs that Thoughts are Uncontrollable”. Confirmatory factor analysis supported the three factor model with all selected goodness-of-fit statistics equivalent to or better than recommended values. Preliminary evidence suggests good internal-consistency, incremental, convergent and discriminant validity in relation to associated measures. The MCQ-HA appears to be a potentially useful predictor of health anxiet

    The development of theory-informed participant-centred interventions to maximise participant retention in randomised controlled trials

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    Acknowledgements We would like to thank all of the participants who volunteered their time to contribute to this study. We would also like to thank all of the teams linked to the host trials we worked with to help identify potential participants. Funding This research is funded by the Chief Scientist Office of the Scottish Government’s Health and Social Care Department [HIPS/16/46]. KG held a Medical Research Council UK Methodology Fellowship during the delivery of this project [MR/L01193X/1]. The publication was supported through a Health Research Board Trials Methodology Research Network award. MDW acknowledges support from the NIHR Newcastle Biomedical Research Centre. MW acknowledges support from the NIHR Imperial Biomedical Research Centre (BRC). The Health Services Research Unit, Institute of Applied Health Sciences (University of Aberdeen), is core-funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. The funders had no involvement in study design, collection, analysis and interpretation of data, reporting or the decision to publish.Peer reviewedPublisher PD

    High-yield methods for accurate two-alternative visual psychophysics in head-fixed mice

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    Research in neuroscience increasingly relies on the mouse, a mammalian species that affords unparalleled genetic tractability and brain atlases. Here, we introduce high-yield methods for probing mouse visual decisions. Mice are head-fixed, facilitating repeatable visual stimulation, eye tracking, and brain access. They turn a steering wheel to make two alternative choices, forced or unforced. Learning is rapid thanks to intuitive coupling of stimuli to wheel position. The mouse decisions deliver high-quality psychometric curves for detection and discrimination and conform to the predictions of a simple probabilistic observer model. The task is readily paired with two-photon imaging of cortical activity. Optogenetic inactivation reveals that the task requires mice to use their visual cortex. Mice are motivated to perform the task by fluid reward or optogenetic stimulation of dopamine neurons. This stimulation elicits a larger number of trials and faster learning. These methods provide a platform to accurately probe mouse vision and its neural basis

    Developing reading-writing connections; the impact of explicit instruction of literary devices on the quality of children's narrative writing

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    The purpose of this collaborative schools-university study was to investigate how the explicit instruction of literary devices during designated literacy sessions could improve the quality of children's narrative writing. A guiding question for the study was: Can children's writing can be enhanced by teachers drawing attention to the literary devices used by professional writers or “mentor authors”? The study was conducted with 18 teachers, working as research partners in nine elementary schools over one school year. The research group explored ways of developing children as reflective authors, able to draft and redraft writing in response to peer and teacher feedback. Daily literacy sessions were complemented by weekly writing workshops where students engaged in authorial activity and experienced writers' perspectives and readers' demands (Harwayne, 1992; May, 2004). Methods for data collection included video recording of peer-peer and teacher-led group discussions and audio recording of teacher-child conferences. Samples of children's narrative writing were collected and a comparison was made between the quality of their independent writing at the beginning and end of the research period. The research group documented the importance of peer-peer and teacher-student discourse in the development of children's metalanguage and awareness of audience. The study suggests that reading, discussing, and evaluating mentor texts can have a positive impact on the quality of children's independent writing

    People of the British Isles: preliminary analysis of genotypes and surnames in a UK control population

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    There is a great deal of interest in fine scale population structure in the UK, both as a signature of historical immigration events and because of the effect population structure may have on disease association studies. Although population structure appears to have a minor impact on the current generation of genome-wide association studies, it is likely to play a significant part in the next generation of studies designed to search for rare variants. A powerful way of detecting such structure is to control and document carefully the provenance of the samples involved. Here we describe the collection of a cohort of rural UK samples (The People of the British Isles), aimed at providing a well-characterised UK control population that can be used as a resource by the research community as well as providing fine scale genetic information on the British population. So far, some 4,000 samples have been collected, the majority of which fit the criteria of coming from a rural area and having all four grandparents from approximately the same area. Analysis of the first 3,865 samples that have been geocoded indicates that 75% have a mean distance between grandparental places of birth of 37.3km, and that about 70% of grandparental places of birth can be classed as rural. Preliminary genotyping of 1,057 samples demonstrates the value of these samples for investigating fine scale population structure within the UK, and shows how this can be enhanced by the use of surnames
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