100 research outputs found

    Insensitivity of visual short-term memory to irrelevant visual information

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    Several authors have hypothesised that visuo-spatial working memory is functionally analogous to verbal working memory. Irrelevant background speech impairs verbal short-term memory. We investigated whether irrelevant visual information has an analogous effect on visual short-term memory, using a dynamic visual noise (DVN) technique known to disrupt visual imagery (Quinn & McConnell, 1996a). Experiment 1 replicated the effect of DVN on pegword imagery. Experiments 2 and 3 showed no effect of DVN on recall of static matrix patterns, despite a significant effect of a concurrent spatial tapping task. Experiment 4 showed no effect of DVN on encoding or maintenance of arrays of matrix patterns, despite testing memory by a recognition procedure to encourage visual rather than spatial processing. Serial position curves showed a one-item recency effect typical of visual short-term memory. Experiment 5 showed no effect of DVN on short-term recognition of Chinese characters, despite effects of visual similarity and a concurrent colour memory task that confirmed visual processing of the characters. We conclude that irrelevant visual noise does not impair visual short-term memory. Visual working memory may not be functionally analogous to verbal working memory, and different cognitive processes may underlie visual short-term memory and visual imagery

    Retrieval Contexts and the Concreteness Effect: Dissociations in Memory of Concrete and Abstract Words

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    Decades of research on the concreteness effect, namely better memory for concrete as compared with abstract words, suggest it is a fairly robust phenomenon. Nevertheless, little attention has been given to limiting retrieval contexts. Two experiments evaluated intentional memory for concrete and abstract word lists in three retrieval contexts: free recall, explicit word-stem completion, and implicit word-stem completion. Concreteness effects were observed in free recall and in explicit word-stem completion, but not in implicit word-stem completion. These findings are consistent with both a bidirectional version of the relational-distinctiveness processing framework (Ruiz-Vargas, Cuevas, & Marschark, 1996) and a second framework combining insights from dual coding theory (Paivio, 1971, 1986) and the transfer appropriate processing framework (Roediger, Weldon, & Challis, 1989). Also, consistent with the relational-distinctiveness framework, the second experiment suggested that concreteness effects might depend on relational processing at encoding: Concreteness effects were observed in explicit memory for related word lists but not for unrelated word lists. © 2005 Psychology Press Ltd

    Being inside. An explorative study into emotional reactions of juvenile offenders to custody

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    At the request of the Department for Judicial Youth Policy (DJJ) of the Ministry of Justice, the WODC (Research and Documentation Centre) conducted an exploratory study into the relation between incarceration and the emotional reactions of juveniles incarcerated in custodial institutions under criminal law. The background to this request relates to signals picked up during work visits to facilities that some young people respond to their custody with a reaction of pride. This reaction is undesirable; it will not stimulate the learning possibilities of juveniles with regard to behavioural change. In mutual consultation with DJJ, it was decided to interpret the request more broadly and to study various emotional reactions exhibited by juvenile offenders with regard to custody. The study was limited to the incarceration of juvenile offenders aged 12 to 24. Studies that relate to interventions or treatment during custody were excluded as much as possible. We also studied the literature regarding to the relation between emotional reactions felt during custody and recidivism

    Application of three-dimensional computed tomography imaging and reconstructive techniques in lung surgery: A mini-review

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    BACKGROUND: Pulmonary surgery is an innovative discipline with increasing demands for minimally invasive techniques in complicated anatomical resections, warranting adequate preoperative imaging of relevant surgical anatomy to ensure safe and radical resection of target lesions. Over the recent years, the emergence of imaging techniques enabling three-dimensional reconstruction has exerted promising influence on pulmonary surgery, facilitating optimal surgical planning and easier identification of the spatial relationship between bronchovascular structures in the individual patient and aiding the safe resection of target pulmonary lesions. The goal of this mini-review is to provide an overview of three-dimensional computed tomography imaging within pulmonary surgery. METHODS: The authors performed a targeted qualitative review of the literature to identify current trends and to provide better understanding of three-dimensional reconstruction within the boundaries of pulmonary surgery. RESULTS: Three-dimensional reconstructive techniques can be used for resectability assessment, identification of surgically relevant interindividual anatomic variance and may improve perioperative outcomes. DISCUSSION: Three-dimensional reconstruction using computed tomography imaging improves surgical planning and there is evidence that it results in shorter operative times, less intraoperative blood loss and lower rates of surgical conversion, as it can be applied both pre- and intraoperatively

    Gene therapy during ex situ heart perfusion: a new frontier in cardiac regenerative medicine?

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    Ex situ organ preservation by machine perfusion can improve preservation of organs for transplantation. Furthermore, machine perfusion opens up the possibilities for selective immunomodulation, creation of tolerance to ischemia-reperfusion injury and/or correction of a pathogenic genetic defect. The application of gene modifying therapies to treat heart diseases caused by pathogenic mutations during ex situ heart perfusion seems promising, especially given the limitations related to delivery of vectors that were encountered during clinical trials using in vivo cardiac gene therapy. By isolating the heart in a metabolically and immunologically favorable environment and preventing off-target effects and dilution, it is possible to directly control factors that enhance the success rate of cardiac gene therapy. A literature search of PubMed and Embase databases was performed to identify all relevant studies regarding gene therapy during ex situ heart perfusion, aiming to highlight important lessons learned and discuss future clinical prospects of this promising approach

    Rapid exome sequencing as a first-tier test in neonates with suspected genetic disorder:results of a prospective multicenter clinical utility study in the Netherlands

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    The introduction of rapid exome sequencing (rES) for critically ill neonates admitted to the neonatal intensive care unit has made it possible to impact clinical decision-making. Unbiased prospective studies to quantify the impact of rES over routine genetic testing are, however, scarce. We performed a clinical utility study to compare rES to conventional genetic diagnostic workup for critically ill neonates with suspected genetic disorders. In a multicenter prospective parallel cohort study involving five Dutch NICUs, we performed rES in parallel to routine genetic testing for 60 neonates with a suspected genetic disorder and monitored diagnostic yield and the time to diagnosis. To assess the economic impact of rES, healthcare resource use was collected for all neonates. rES detected more conclusive genetic diagnoses than routine genetic testing (20% vs. 10%, respectively), in a significantly shorter time to diagnosis (15 days (95% CI 10–20) vs. 59 days (95% CI 23–98, p &lt; 0.001)). Moreover, rES reduced genetic diagnostic costs by 1.5% (€85 per neonate). Conclusion: Our findings demonstrate the clinical utility of rES for critically ill neonates based on increased diagnostic yield, shorter time to diagnosis, and net healthcare savings. Our observations warrant the widespread implementation of rES as first-tier genetic test in critically ill neonates with disorders of suspected genetic origin.What is Known:• Rapid exome sequencing (rES) enables diagnosing rare genetic disorders in a fast and reliable manner, but retrospective studies with neonates admitted to the neonatal intensive care unit (NICU) indicated that genetic disorders are likely underdiagnosed as rES is not routinely used.• Scenario modeling for implementation of rES for neonates with presumed genetic disorders indicated an expected increase in costs associated with genetic testing.What is New:• This unique prospective national clinical utility study of rES in a NICU setting shows that rES obtained more and faster diagnoses than conventional genetic tests.• Implementation of rES as replacement for all other genetic tests does not increase healthcare costs but in fact leads to a reduction in healthcare costs.</p

    A Cardioprotective perfusion protocol limits myocardial functional decline during ex situ heart perfusion

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    Background Ex situ heart perfusion is associated with a significant decline in graft quality related to oxidative stress, inflammation, endothelial dysfunction, and metabolic perturbations. We assessed the effects of a more optimized, cardioprotective normothermic perfusion approach compared to a conventional perfusion protocol in a slaughterhouse model using porcine hearts. Methods A total of 12 hearts were harvested and subjected to 4 hours of normothermic perfusion. The optimized protocol consisted of an adenosine-lidocaine cardioplegic solution, subnormothermic initial reperfusion and controlled rewarming, hemofiltration and supplementation of methylprednisolone and pyruvate. This was compared to a conventional protocol consisting of St. Thomas II cardioplegic solution, normothermic initial reperfusion without hemofiltration or methylprednisolone, and a mixture of glucose and insulin for metabolic support. Results Myocardial function was superior in the optimized group, while significant functional decline was absent. Hearts subjected to the conventional protocol demonstrated a significant reduction in function over time. Conclusions We have developed a further optimized, cardioprotective normothermic ex situ heart perfusion approach and demonstrated significantly improved myocardial function and attenuated functional decline during 4 hours of normothermic perfusion, indicating improved preservation

    Ex Situ Left Ventricular Pressure-Volume Loop Analyses for Donor Hearts: Proof of Concept in an Ovine Experimental Model.

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    Ex situ heart perfusion (ESHP) has emerged as an important strategy to preserve donation after brain death (DBD) and donation after circulatory death (DCD) donor hearts. Clinically, both DBD and DCD hearts are successfully preserved using ESHP. Viability assessment is currently based on biochemical values, while a reliable method for graft function assessment in a physiologic working mode is unavailable. As functional assessment during ESHP has demonstrated the highest predictive value of outcome post-transplantation, this is an important area for improvement. In this study, a novel method for ex situ assessment of left ventricular function with pressure-volume loop analyses is evaluated. Ovine hearts were functionally evaluated during normothermic ESHP with the novel pressure-volume loop system. This system provides an afterload and adjustable preload to the left ventricle. By increasing the preload and measuring end-systolic elastance, the system could successfully assess the left ventricular function. End-systolic elastance at 60 min and 120 min was 2.8 ± 1.8 mmHg/mL and 2.7 ± 0.7 mmHg/mL, respectively. In this study we show a novel method for functional graft assessment with ex situ pressure-loop analyses during ESHP. When further validated, this method for pressure-volume assessments, could be used for better graft selection in both DBD and DCD donor hearts
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