603 research outputs found

    Instantaneous effects of mindfulness meditation on tennis return performance in elite junior athletes completing an implicitly sequenced serve return task

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    Single-session meditation augmentation of sport-specific skill performance was tested with elite junior tennis athletes. Athletes completed one of two styles of mindfulness meditation (focused-attention or open-monitoring) or a control listening condition prior to performing an implicitly sequenced tennis serve return task involving the goal of hitting a target area placed on the service court. Unbeknownst to athletes, six distinct serves followed a repeating second-order conditional sequence for two task blocks before the sequence was altered in a third transfer block. Task performance was operationalized as serve return outcome and analyzed using beta regression modeling. Models analyzed group by block differences in the proportion of returned serves (i.e., non-aces), returns placed in the service court, and target hits. Contrary to previous laboratory findings, results did not support meditation-related augmentation of performance and/or sequence learning. In fact, compared to control, meditation may have impaired performance improvements and acquisition of serve sequence information. It is possible that the effects of single-session meditation seen in laboratory research may not extend to more complex motor tasks, at least in highly-trained adolescents completing a well-learned skill. Further research is required to elucidate the participant, task, and meditation-related characteristics that might promote single-session meditation performance enhancement

    Imaging of ischemia, obstruction and infection in the abdomen

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    Intestinal ischemia is a serious condition that continues to be associated with mortalities in excess of 70%. Intestinal obstruction and gastrointestinal tract sepsis are common conditions, accounting for a large proportion of patients admitted to emergency departments with acute abdominal symptoms. This article discusses the imaging methods and key findings of these entities in the emergency radiology department. The article includes imaging examples, diagnostic options, protocol selections, diagnostic criteria, and differential diagnoses

    Optimizing parameters of an open-source airway segmentation algorithm using different CT images.

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    Background: Computed tomography (CT) helps physicians locate and diagnose pathological conditions. In some conditions, having an airway segmentation method which facilitates reconstruction of the airway from chest CT images can help hugely in the assessment of lung diseases. Many efforts have been made to develop airway segmentation algorithms, but methods are usually not optimized to be reliable across different CT scan parameters. Methods: In this paper, we present a simple and reliable semi-automatic algorithm which can segment tracheal and bronchial anatomy using the open-source 3D Slicer platform. The method is based on a region growing approach where trachea, right and left bronchi are cropped and segmented independently using three different thresholds. The algorithm and its parameters have been optimized to be efficient across different CT scan acquisition parameters. The performance of the proposed method has been evaluated on EXACT’09 cases and local clinical cases as well as on a breathing pig lung phantom using multiple scans and changing parameters. In particular, to investigate multiple scan parameters reconstruction kernel, radiation dose and slice thickness have been considered. Volume, branch count, branch length and leakage presence have been evaluated. A new method for leakage evaluation has been developed and correlation between segmentation metrics and CT acquisition parameters has been considered. Results: All the considered cases have been segmented successfully with good results in terms of leakage presence. Results on clinical data are comparable to other teams’ methods, as obtained by evaluation against the EXACT09 challenge, whereas results obtained from the phantom prove the reliability of the method across multiple CT platforms and acquisition parameters. As expected, slice thickness is the parameter affecting the results the most, whereas reconstruction kernel and radiation dose seem not to particularly affect airway segmentation. Conclusion: The system represents the first open-source airway segmentation platform. The quantitative evaluation approach presented represents the first repeatable system evaluation tool for like-for-like comparison between different airway segmentation platforms. Results suggest that the algorithm can be considered stable across multiple CT platforms and acquisition parameters and can be considered as a starting point for the development of a complete airway segmentation algorithm

    Reduction of guide needle streak artifact in CT-guided biopsy

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    Purpose: Computed tomography (CT)–guided core needle biopsy (CNB) can be affected by streak artifact obscuring the needle tip. This study investigates factors that influence the occurrence and severity of streak artifact during CNB. Materials and Methods: Eight coaxial guide needles of two sizes from two manufacturers with and without stylets were imaged in a CT phantom, with CT reconstructed with adaptive statistical iterative reconstruction and filtered back projection. CNB-related streak artifact was quantified with profile analysis in an image-processing program. Differences between maximum attenuation at the needle tip and minimum attenuation in the streak artifact were compared for each variable. Diagnostic acceptability and streak artifact were subjectively assessed on each phantom image and on 40 clinical CNB procedures by three independent blinded reviewers following training case review. Results: Artifact was significantly less with the central stylet removed versus in situ (median, 1,145 HU vs 3,390 HU; P < .001) for all needles, and less for 19-gauge needles versus 17-gauge needles (median, 1,334 HU vs 2,780 HU, respectively; P = .006). There were no differences based on manufacturer (P = .906) or reconstruction algorithm (P = .524). Independent reviews found that streak artifact was significantly reduced when the central stylet was removed (κ = 0.875–1.0; P < .001), and needle tip position was better in cases in which the stylet was removed (κ = 0.231–0.711; P < .001). Conclusions: Streak artifact can be reduced and needle tip visualization improved by confirming final biopsy needle position with the central stylet removed on CT and using smaller-gauge guide needles

    Google Trends indicators to inform water planning and drought management

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    Indicators are important tools for tracking the socio- environmental impacts of droughts and building resilience to climate change. We begin with an overview of metrics used for water planning and drought management, with particular emphasis on the UK. We explain how considerations of cost, immediacy, access, consistency, relevance, reliability and others denote the suitability of information for developing new indicators. We then demonstrate the potential of Google Trends (GT) online search data as drought indicators for England and Ireland. We show that search terms such as ‘drought’, ‘water butt’ and ‘hosepipe ban’ correlate significantly with conventional hydroclimatic data as well as with news-paper reports of various drought impacts during the period 2011–2022. GT data also show evidence of rising interest in water saving technologies, especially for outdoor water use. Meanwhile, online searches for ‘Defra’ and ‘Environment Agency’ have declined and are more often associated with flood episodes than droughts. Interest in water companies in England is more likely around hosepipe bans than water leakage (although this varies by company). We discuss the impli-cations of these findings for targeting information campaigns, plus prospects for monitoring drought impacts and public sentiment in near real- time

    Single particle diversity and mixing state measurements

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    A newly developed framework for quantifying aerosol particle diversity and mixing state based on information-theoretic entropy is applied for the first time to single particle mass spectrometry field data. Single particle mass fraction estimates for black carbon, organic aerosol, ammonium, nitrate and sulfate, derived using single particle mass spectrometer, aerosol mass spectrometer and multi-angle absorption photometer measurements are used to calculate single particle species diversity (<i>D<sub>i</sub></i>). The average single particle species diversity (<i>D</i><sub>&alpha;</sub>) is then related to the species diversity of the bulk population (<i>D</i><sub>&gamma;</sub>) to derive a mixing state index value (&chi;) at hourly resolution. The mixing state index is a single parameter representation of how internally/externally mixed a particle population is at a given time. The index describes a continuum, with values of 0 and 100% representing fully external and internal mixing, respectively. This framework was applied to data collected as part of the MEGAPOLI winter campaign in Paris, France, 2010. <i>D<sub>i</sub></i> values are low (~ 2) for fresh traffic and wood-burning particles that contain high mass fractions of black carbon and organic aerosol but low mass fractions of inorganic ions. Conversely, <i>D<sub>i</sub></i> values are higher (~ 4) for aged carbonaceous particles containing similar mass fractions of black carbon, organic aerosol, ammonium, nitrate and sulfate. Aerosol in Paris is estimated to be 59% internally mixed in the size range 150–1067 nm, and mixing state is dependent both upon time of day and air mass origin. Daytime primary emissions associated with vehicular traffic and wood-burning result in low &chi; values, while enhanced condensation of ammonium nitrate on existing particles at night leads to higher &chi; values. Advection of particles from continental Europe containing ammonium, nitrate and sulfate leads to increases in <i>D</i><sub>&alpha;</sub>, <i>D</i><sub>&gamma;</sub> and &chi;. The mixing state index represents a useful metric by which to compare and contrast ambient particle mixing state at other locations globally

    No moderating effect of 5-HTTLPR on associations between antenatal anxiety and infant behavior.

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    OBJECTIVE: Maternal antenatal anxiety is associated with an increased risk of behavioral disturbances in offspring. Recent work has suggested that the effect of maternal antenatal anxiety on infant temperament at 6 months is moderated by the serotonin transporter polymorphism 5-HTTLPR, with carriers of the short allele more susceptible to the adverse behavioral outcomes of maternal antenatal anxiety. These findings, however, are yet to be replicated and extended beyond infancy. The aim of the current study was to assess this same potential moderator (5-HTTLPR) in a large population-based cohort study, and to determine whether or not the effects persist into childhood and early adolescence. METHOD: Data from the Avon Longitudinal Study of Children and Parents (ALSPAC) cohort (N = 3,946) were used to assess whether the 5-HTTLPR genotype moderated the association between self-reported maternal antenatal anxiety (Crown Crisp Index) in pregnancy, and child temperament at 6 months (Infant Temperament Questionnaire), and also later behavioral and emotional problems on the Strengths and Difficulties Questionnaire from age 4 to 13 years. RESULTS: We found no evidence to suggest that the 5-HTTLPR polymorphism moderated the effects of maternal antenatal anxiety on infant temperament at 6 months or infant behavioral and emotional problems from childhood through to adolescence. CONCLUSION: Our results, based on a large prospective community sample that assessed children from infancy to early adolescence, provide a thorough test of, but no evidence for, a genetic moderation of the effects of maternal antenatal anxiety by 5-HTTLPR

    High Pressure Processing of Dairy Foods

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    End of Project ReportThe term High Pressure Processing (HPP) is used to describe the technology whereby products are exposed to very high pressures in the region of 50 - 800 MPa (500 - 8000 Atmospheres). The potential application of HPP in the food industry has gained popularity in recent years, due to developments in the construction of HPP equipment which makes the technology more affordable. Applying HPP to food products results in modifications to interactions between individual components, rates of enzymatic reactions and inactivation of micro-organisms. The first commercial HPP products appeared on the market in 1991 in Japan, where HPP is now being used commercially for products such as jams, sauces, fruit juices, rice cakes and desserts. The pioneering research into the application of HPP to milk dates back to the end of the 19th century. Application of HPP to milk has been shown to modify its gel forming characteristics as well as reducing its microbial load. HPP offers the potential to induce similar effects to those generated by heat on milk protein. Recent reports have also indicated that HPP could accelerate the ripening of cheese. Much of the Irish cheese industry is based on the production of Cheddar cheese, the ripening time for which can vary from 4 - 12 months or more, depending on grade. A substantial portion of the cost associated with Cheddar manufacture is therefore attributed to storage under controlled conditions during ripening. Thus, any technology which may accelerate the ripening of Cheddar cheese while maintaining a balanced flavour and texture is of major economic significance. While food safety is a dominant concern, consumers are increasingly demanding foods that maintain their natural appearance and flavour, while free of chemical preservatives. HPP offers the food industry the possibility of achieving these twin goals as this technology can lead to reduced microbial loads without detrimentally effecting the nutritional or sensory qualities of the product. The development of food ingredients with novel functional properties offers the dairy industry an opportunity to revitalise existing markets and develop new ones. HPP can lead to modifications in the structure of milk components, in particular protein, which may provide interesting possibilities for the development of high value nutritional and functional ingredients. Hence these projects set out to investigate the potential of HPP in the dairy industry and to identify products and processes to which it could be applied.Department of Agriculture, Food and the Marin
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