1,635 research outputs found

    The effect of fear‐inducing content on memory for advertisements and on retroactive and proactive interference of programme information

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    The current study focused on whether fear‐inducing content in television advertisements leads to better memory for the advertisement but also impairs memory for programme information that either precedes the advertisements (retroactive interference) or that follows the advertisements (proactive interference). Fifty‐four participants (48 female) aged 18 to 55 watched a programme that had an advertisement break in the centre. This consisted of 6 advertisements with either fear‐inducing or nonfear‐inducing content. Participants were tested on their recall and recognition of the advertisement information as well as their recall of the first half and second half of the programme. The results indicated that fear‐inducing advertisements were better recalled than those that elicited no fear, and there was also evidence of proactive interference from fear‐inducing advertisements on programme recall. Limitations and implications of the study are discussed

    Emerging roles of epigenetic mechanisms in the enduring effects of early-life stress and experience on learning and memory.

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    Epigenetic mechanisms are involved in programming gene expression throughout development. In addition, they are key contributors to the processes by which early-life experience fine-tunes the expression levels of key neuronal genes, governing learning and memory throughout life. Here we describe the long-lasting, bi-directional effects of early-life experience on learning and memory. We discuss how enriched postnatal experience enduringly augments spatial learning, and how chronic early-life stress results in persistent and progressive deficits in the structure and function of hippocampal neurons. The existing and emerging roles of epigenetic mechanisms in these fundamental neuroplasticity phenomena are illustrated

    Bilateral fibular fractures in a pre-ambulant infant

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    Multiple long-bone fractures, particularly bilateral fractures, are of moderate specificity for inflicted injury (physical abuse) in infants and young children. Bilateral healing fractures of the fibulae are rare and, depending on age, raise the suspicion of inflicted injury. We report healing undisplaced fractures of both fibulae, in almost identical positions, in a pre-ambulant infant. The caregivers reported that the infant repeatedly banged his legs against the metal frame of his playpen. A video of this mechanism was provided to the instructed radiology expert and showed that the point of impact of the infant’s legs against the metal frame was at a similar level to the radiographic abnormalities. This mechanism was therefore believed to be consistent with the injuries, resulting in a diagnosis of self-inflicted bilateral fibular fractures and not of inflicted injury

    The Pervasive Crisis of Diminishing Radiation Therapy Access for Vulnerable Populations in the United States—Part 4: Appalachian Patients

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    Purpose: Compared with the rest of the United States, the population of Appalachia has lower education levels, higher rates of poverty, and limited access to health care. The presence of disparities in radiation therapy (RT) access for Appalachian patients with cancer has rarely been examined. Methods and materials: The National Cancer Institute initiatives toward addressing disparities in treatment access for rural populations were examined. An extensive literature search was undertaken for studies investigating RT access disparities in Appalachian patients, beginning with the most common cancers in these patients (lung, colorectal, and cervical). Results: Although the literature investigating RT access disparities in Appalachia is relatively sparse, studies examining lung, colorectal, cervical, prostate, head and neck, breast, and esophageal cancer, as well as lymphoma, indicate an unfortunate commonality in barriers to optimal RT access for Appalachian patients with cancer. These barriers are predominantly socioeconomic in nature (low income and lack of private insurance) but are exacerbated by paucities in both the number and quality of radiation centers that are accessible to this patient population. Conclusions: Regardless of organ system, there are significant barriers for Appalachian patients with cancer to receive RT. Such diminished access is alarming and warrants resources devoted to addressing these disparities, which often go overlooked because of the assumption that the overall wealth of the United States is tangibly applicable to all of its citizens. Without intelligently targeted investments of time and finances in this arena, there is great risk of exacerbating rather than alleviating the already heavy burden facing Appalachian patients with cancer

    Prioritized Sweeping Neural DynaQ with Multiple Predecessors, and Hippocampal Replays

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    During sleep and awake rest, the hippocampus replays sequences of place cells that have been activated during prior experiences. These have been interpreted as a memory consolidation process, but recent results suggest a possible interpretation in terms of reinforcement learning. The Dyna reinforcement learning algorithms use off-line replays to improve learning. Under limited replay budget, a prioritized sweeping approach, which requires a model of the transitions to the predecessors, can be used to improve performance. We investigate whether such algorithms can explain the experimentally observed replays. We propose a neural network version of prioritized sweeping Q-learning, for which we developed a growing multiple expert algorithm, able to cope with multiple predecessors. The resulting architecture is able to improve the learning of simulated agents confronted to a navigation task. We predict that, in animals, learning the world model should occur during rest periods, and that the corresponding replays should be shuffled.Comment: Living Machines 2018 (Paris, France

    Neuron-restrictive silencer factor-mediated hyperpolarization-activated cyclic nucleotide gated channelopathy in experimental temporal lobe epilepsy.

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    ObjectiveEnduring, abnormal expression and function of the ion channel hyperpolarization-activated cyclic adenosine monophosphate gated channel type 1 (HCN1) occurs in temporal lobe epilepsy (TLE). We examined the underlying mechanisms, and investigated whether interfering with these mechanisms could modify disease course.MethodsExperimental TLE was provoked by kainic acid-induced status epilepticus (SE). HCN1 channel repression was examined at mRNA, protein, and functional levels. Chromatin immunoprecipitation was employed to identify the transcriptional mechanism of repressed HCN1 expression, and the basis for their endurance. Physical interaction of the repressor, NRSF, was abolished using decoy oligodeoxynucleotides (ODNs). Video/electroencephalographic recordings were performed to assess the onset and initial pattern of spontaneous seizures.ResultsLevels of NRSF and its physical binding to the Hcn1 gene were augmented after SE, resulting in repression of HCN1 expression and HCN1-mediated currents (I(h) ), and reduced I(h) -dependent resonance in hippocampal CA1 pyramidal cell dendrites. Chromatin changes typical of enduring, epigenetic gene repression were apparent at the Hcn1 gene within a week after SE. Administration of decoy ODNs comprising the NRSF DNA-binding sequence (neuron restrictive silencer element [NRSE]), in vitro and in vivo, reduced NRSF binding to Hcn1, prevented its repression, and restored I(h) function. In vivo, decoy NRSE ODN treatment restored theta rhythm and altered the initial pattern of spontaneous seizures.InterpretationAcquired HCN1 channelopathy derives from NRSF-mediated transcriptional repression that endures via chromatin modification and may provide insight into the mechanisms of a number of channelopathies that coexist with, and may contribute to, the conversion of a normal brain into an epileptic one

    Cone photoreceptor definition on adaptive optics retinal imaging

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    To quantitatively analyse cone photoreceptor matrices on images captured on an adaptive optics (AO) camera and assess their correlation to well-established parameters in the retinal histology literature

    Early-life experience reduces excitation to stress-responsive hypothalamic neurons and reprograms the expression of corticotropin-releasing hormone.

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    Increased sensory input from maternal care attenuates neuroendocrine and behavioral responses to stress long term and results in a lifelong phenotype of resilience to depression and improved cognitive function. Whereas the mechanisms of this clinically important effect remain unclear, the early, persistent suppression of the expression of the stress neurohormone corticotropin-releasing hormone (CRH) in hypothalamic neurons has been implicated as a key aspect of this experience-induced neuroplasticity. Here, we tested whether the innervation of hypothalamic CRH neurons of rat pups that received augmented maternal care was altered in a manner that might promote the suppression of CRH expression and studied the cellular mechanisms underlying this suppression. We found that the number of excitatory synapses and the frequency of miniature excitatory synaptic currents onto CRH neurons were reduced in "care-augmented" rats compared with controls, as were the levels of the glutamate vesicular transporter vGlut2. In contrast, analogous parameters of inhibitory synapses were unchanged. Levels of the transcriptional repressor neuron-restrictive silencer factor (NRSF), which negatively regulates Crh gene transcription, were markedly elevated in care-augmented rats, and chromatin immunoprecipitation demonstrated that this repressor was bound to a cognate element (neuron-restrictive silencing element) on the Crh gene. Whereas the reduced excitatory innervation of CRH-expressing neurons dissipated by adulthood, increased NRSF levels and repression of CRH expression persisted, suggesting that augmented early-life experience reprograms Crh gene expression via mechanisms involving transcriptional repression by NRSF

    The tripartite partnership between female entrepreneurs, banks and governments in female entrepreneurship-development: A case study of Zambia

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    Purpose – This paper provides insights on the void between the needs and demands of bank finance from female entrepreneurs and the supply as well as the approaches of banks for that finance. In addition, it creates a conceptual framework recognising a tripartite and dynamic partnership among female entrepreneurs, banks and governments as essential to female entrepreneurship-development, based on Zambia as the context. Design/methodology/approach – Concepts and theories are explained to construct a conceptual framework using the lens of multi-polar network theory and stakeholder engagement theory. In-depth discussions are facilitated through a bilateral partnership between each party and tripartite partnerships among female entrepreneurs, banks and governments. Findings – The framework presents how female entrepreneurs, banks and governments are interconnected in the network as mutually benefiting stakeholders and shows their collective contribution to female entrepreneurship-development within certain contexts. The findings suggest that the sustainable development of female entrepreneurship depends on a dynamic tripartite partnership among female entrepreneurs, banks and governments. Research limitations/implications – The conceptual framework has important implications when setting up a nation’s enterprise development strategies and policies promoting inclusivity and diversity among a nation’s entrepreneurs. The contributions and the dynamic relationship of the three stakeholder groups should be acknowledged and considered in order to achieve the sustainable development female entrepreneur enterprises. The framework can be generalised to other emerging economies with similar social, economic and cultural profiles to Zambia, particularly in sub-Saharan African countries with patriarchal norms. Originality/value – This paper extends multi-polar (network) theory and Stakeholder Management engagement theory, previously explained in homogeneous firms, to more complex and dynamic partnerships among heterogeneous organisations, i.e. female entrepreneurs, banks and governments

    Compulsive checking behavior of quinpirole-sensitized rats as an animal model of Obsessive-Compulsive Disorder(OCD): form and control

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    BACKGROUND: A previous report showed that the open field behavior of rats sensitized to the dopamine agonist quinpirole satisfies 5 performance criteria for compulsive checking behavior. In an effort to extend the parallel between the drug-induced phenomenon and human obsessive-compulsive disorder (OCD), the present study investigated whether the checking behavior of quinpirole rats is subject to interruption, which is an attribute characteristic of OCD compulsions. For this purpose, the rat's home-cage was placed into the open field at the beginning or the middle of a 2-hr test. RESULTS: Introduction of the home-cage reduced checking behavior, as rats stayed inside the cage. After 40 min, checking resurfaced, as quinpirole rats exited the home-cage often. An unfamiliar cage had no such effects on quinpirole rats or saline controls. CONCLUSIONS: Checking behavior induced by quinpirole is not irrepressible but can be suspended. Results strengthen the quinpirole preparation as an animal model of OCD compulsive checking
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