299 research outputs found

    Reconciliation of weak pairwise spike-train correlations and highly coherent local field potentials across space

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    Chronic and acute implants of multi-electrode arrays that cover several mm2^2 of neural tissue provide simultaneous access to population signals like extracellular potentials and the spiking activity of 100 or more individual neurons. While the recorded data may uncover principles of brain function, its interpretation calls for multiscale computational models with corresponding spatial dimensions and signal predictions. Such models can facilitate the search of mechanisms underlying observed spatiotemporal activity patterns in cortex. Multi-layer spiking neuron network models of local cortical circuits covering ~1 mm2^2 have been developed, integrating experimentally obtained neuron-type specific connectivity data and reproducing features of in-vivo spiking statistics. With forward models, local field potentials (LFPs) can be computed from the simulated spiking activity. To account for the spatial scale of common neural recordings, we extend a local network and LFP model to 4x4 mm2^2. The upscaling preserves the neuron densities, and introduces distance-dependent connection probabilities and delays. As detailed experimental connectivity data is partially lacking, we address this uncertainty in model parameters by testing parameter combinations within biologically plausible bounds. Based on model predictions of spiking activity and LFPs, we find that the upscaling procedure preserves the overall spiking statistics of the original model and reproduces asynchronous irregular spiking across populations and weak pairwise spike-train correlations observed in sensory cortex. In contrast with the weak spike-train correlations, the correlation of LFP signals is strong and distance-dependent, compatible with experimental observations. Enhanced spatial coherence in the low-gamma band may explain the recent experimental report of an apparent band-pass filter effect in the spatial reach of the LFP.Comment: 44 pages, 9 figures, 5 table

    The Primary Energy Dependence of Backscattered Electron Images Up to 100 keV

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    The backscattered electron coefficient is known to be primarily dependent on the atomic number of the sample. If the atomic number increases, the backscattered electron coefficient increases, which results in a higher intensity in the backscattered electron image. The dependence of the primary electron energy is somewhat more complicated. Using photographic material (with composition AgBr-AgI), it is seen that the contrast in the backscattered electron image increases with the primary electron energy. Using three independent methods, based on image analysis techniques, it is shown that the difference between the backscattered electron coefficient of AgBr and AgI increases with the primary electron energy in the range from 40 to 100 keV

    Research priorities in pediatric parenteral nutrition: a consensus and perspective from ESPGHAN/ESPEN/ESPR/CSPEN

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    We acknowledge all the authors of the ESPGHAN/ESPR/ESPEN/CSPEN pediatric parenteral nutrition guidelines for their contributions and vote (Christian Braegger, University Children’s Hospital, Zurich, Switzerland; Jiri Bronsky, University Hospital Motol, Prague, Czech Republic; Cristina Campoy, Department of Paediatrics, School of Medicine, University of Granada, Granada, Spain; Magnus Domellof, Department of Clinical Sciences, Pediatrics, Umeå University, Sweden; Nicholas Embleton, Newcastle University, Newcastle upon Tyne, UK; Mary Fewtrell, UCL Great Ormond Street Institute of Child Health, London, UK; Natasa Fidler, University Medical Centre Ljubljana, Ljubljana, Slovenia; Axel Franz, University Children’s Hospital, Tuebingen, Germany; Oliver Goulet, University Sordonne-Paris-Cite; Paris-Descartes Medical School, Paris, France; Corina Hartmann, Schneider Children’s Medical Center of Israel, Petach Tikva, Israel and Carmel Medical Center, Israel; Susan Hill, Great Ormond Street Hospital for Children, NHS Foundation Trust and UCL Institute of Child Health, London, UK; Iva Hojsak, Children’s Hospital Zagreb, University of Zagreb School of Medicine, University of J. J. Strossmayer School of Medicine Osijek, Croatia; Sylvia Iacobelli, CHU La Reunion, Saint Pierre, France; Frank Jochum, Ev. Waldkrankenhaus Spandau, Berlin, Germany; Koen Joosten, Department of Pediatrics and Pediatric Surgery, Intensive Care, Erasmus MC Sophia Children’s Hospital, Rotterdam, The Netherlands; Sanja Kolacek, Children’s Hospital, University of Zagreb School of Medicine, Zagreb, Croatia; Alexandre Lapillone, Paris-Descartes University, Paris, France; Szimonetta Lohner, Department of Pediatrics, University of Pecs, Pecs, Hungary; Dieter Mesotten, KU Leuven, Leuven, Belgium; Walter Mihatsch, Ulm University, Ulm, and Helios Hospital, Pforzheim, Germany; Francis Mimouni, Department of Pediatrics, Division of Neonatology, The Wilf Children’s Hospital, the Shaare Zedek Medical Center, Jerusalem, and the Tel Aviv University, Tel Aviv, Israel; Christian Molgaard, Department of Nutrition, Exercise and Sports, University of Copenhagen, and Paediatric Nutrition Unit, Rigshospitalet, Copenhagen, Denmark; Sissel Moltu, Oslo University Hospital, Oslo, Norway; Antonia Nomayo, Ev. Waldkrankenhaus Spandau, Berlin, Germany; John Puntis, The General Infirmary at Leeds, Leeds, UK; Arieh Riskin, Bnai Zion Medical Center, Rappaport Faculty of Medicine, Technion, Haifa, Israel; Miguel Saenz de Pipaon, Department of Neonatology, La Paz University Hospital, Red de Salud Materno Infantil y Desarrollo e SAMID, Universidad Autonoma de Madrid, Madrid, Spain; Raanan Shamir, Schneider Children’s Medical Center of Israel, Petach Tikva, Israel; Tel Aviv University, Tel Aviv, Israel; Peter Szitanyi, General University Hospital, First Faculty of Medicine, Charles University in Prague, Czech Republic; Merit Tabbers, Emma Children’s Hospital, Amsterdam UMC, Amsterdam, The Netherlands; Chris van den Akker, Emma Children’s Hospital, Amsterdam UMC, Amsterdam, The Netherlands; Hans van Goudoever, Emma Children’s Hospital, Amsterdam UMC, Amsterdam, The Netherlands; Sacha Verbruggen, Department of Pediatrics and Pediatric Surgery, Intensive Care, Erasmus MC-Sophia Children’s Hospital, Rotterdam, The Netherlands; Cai Wei, Shanghai Jiao Tong University, Shanghai, China; Weihui Yan, Department of Gastroenterology and Nutrition, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China) and the members of the ESPR Section on Nutrition, Gastroenterology and Metabolism (Fredrik Ahlsson, Uppsala University Children’s Hospital and Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden; Sertac Arslanoglu, Division of Neonatology, Department of Pediatrics, Istanbul Medeniyet University, Istanbul, Turkey; Wolfgang Bernhard, Department of Neonatology, Children’s Hospital, Faculty of Medicine, Eberhard-Karls- University, Tübingen, Germany; Janet Berrington, Newcastle Neonatal Service, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK; Signe Bruun, Hans Christian Andersen Hospital for Children and Adolescents, Odense University Hospital, Odense, Denmark; Christoph Fusch, Department of Pediatrics, Paracelsus Medical School, General Hospital of Nuremberg, Nuremberg, Germany; Shalabh Garg, South Tees Hospitals, Middlesborough, UK; Maria Gianni, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy; Ann Hellstrom, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden; Claus Klingenberg, Department of Pediatrics and Adolescence Medicine, University Hospital of North Norway, Tromsø, Norway; Helen Mactier, Neonatal Unit, Princess Royal Maternity Hospital, Glasgow, UK; Neena Modi, Section of Neonatal Medicine, Department of Medicine, Chelsea and Westminster Campus, Imperial College London, London, UK; Niels Rochow, Division of Neonatology, Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada; Paola Rogerro, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy; Umberto Simeoni, Division of Pediatrics, CHUV & University of Lausanne, Lausanne, Switzerland; Atul Singhal, Paediatric Nutrition, UCL Great Ormond Street Institute of Child Health, London, UK.; Ulrich Thome, Department of Neonatology, Universitatsklinikum Leipzig, Leipzig, Germany; Anne Twomey, Department of Neonatology, The National Maternity Hospital, Dublin, Ireland; Mireille Vanpee, Karolinska University Hospital, Stockholm, Sweden; Gitte Zachariassen, Hans Christian Andersen Hospital for Children and Adolescents, Odense University Hospital, Odense, Denmark) for their vote.Parenteral nutrition is used to treat children that cannot be fully fed by the enteral route. While the revised ESPGHAN/ ESPEN/ESPR/CSPEN pediatric parenteral nutrition guidelines provide clear guidance on the use of parenteral nutrition in neonates, infants, and children based on current available evidence, they have helped to crystallize areas where research is lacking or more studies are needed in order to refine recommendations. This paper collates and discusses the research gaps identified by the authors of each section of the guidelines and considers each nutrient or group of nutrients in turn, together with aspects around delivery and organization. The 99 research priorities identified were then ranked in order of importance by clinicians and researchers working in the field using a survey methodology. The highest ranked priority was the need to understand the relationship between total energy intake, rapid catch-up growth, later metabolic function, and neurocognitive outcomes. Research into the optimal intakes of macronutrients needed in order to achieve optimal outcomes also featured prominently. Identifying research priorities in PN should enable research to be focussed on addressing key issues. Multicentre trials, better definition of exposure and outcome variables, and long-term metabolic and developmental follow-up will be key to achieving this

    A weak scientific basis for gaming disorder: let us err on the side of caution

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    We greatly appreciate the care and thought that is evident in the 10 commentaries that discuss our debate paper, the majority of which argued in favor of a formalized ICD-11 gaming disorder. We agree that there are some people whose play of video games is related to life problems. We believe that understanding this population and the nature and severity of the problems they experience should be a focus area for future research. However, moving from research construct to formal disorder requires a much stronger evidence base than we currently have. The burden of evidence and the clinical utility should be extremely high, because there is a genuine risk of abuse of diagnoses. We provide suggestions about the level of evidence that might be required: transparent and preregistered studies, a better demarcation of the subject area that includes a rationale for focusing on gaming particularly versus a more general behavioral addictions concept, the exploration of non-addiction approaches, and the unbiased exploration of clinical approaches that treat potentially underlying issues, such as depressive mood or social anxiety first. We acknowledge there could be benefits to formalizing gaming disorder, many of which were highlighted by colleagues in their commentaries, but we think they do not yet outweigh the wider societal and public health risks involved. Given the gravity of diagnostic classification and its wider societal impact, we urge our colleagues at the WHO to err on the side of caution for now and postpone the formalization

    Response rates and selection problems, with emphasis on mental health variables and DNA sampling, in large population-based, cross-sectional and longitudinal studies of adolescents in Norway

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    Background Selection bias is a threat to the internal validity of epidemiological studies. In light of a growing number of studies which aim to provide DNA, as well as a considerable number of invitees who declined to participate, we discuss response rates, predictors of lost to follow-up and failure to provide DNA, and the presence of possible selection bias, based on five samples of adolescents. Methods We included nearly 7,000 adolescents from two longitudinal studies of 18/19 year olds with two corresponding cross-sectional baseline studies at age 15/16 (10th graders), and one cross-sectional study of 13th graders (18/19 years old). DNA was sampled from the cheek mucosa of 18/19 year olds. Predictors of lost to follow-up and failure to provide DNA were studied by Poisson regression. Selection bias in the follow-up at age 18/19 was estimated through investigation of prevalence ratios (PRs) between selected exposures (physical activity, smoking) and outcome variables (general health, mental distress, externalizing problems) measured at baseline. Results Out of 5,750 who participated at age 15/16, we lost 42% at follow-up at age 18/19. The percentage of participants who gave their consent to DNA provision was as high as the percentage that consented to a linkage of data with other health registers and surveys, approximately 90%. Significant predictors of lost to follow-up and failure to provide DNA samples in the present genetic epidemiological study were: male gender; non-western ethnicity; postal survey compared with school-based; low educational plans; low education and income of father; low perceived family economy; unmarried parents; poor self-reported health; externalized symptoms and smoking, with some differences in subgroups of ethnicity and gender. The association measures (PRs) were quite similar among participants and all invitees, with some minor discrepancies in subgroups of non-western boys and girls. Conclusions Lost to follow-up had marginal impact on the estimated prevalence ratios. It is not likely that the invitation to provide DNA influenced the response rates of 18/19 year olds. Non-western ethnicity, male gender and characteristics related to a low social class and general and mental health problems measured at baseline are associated with lost to follow-up and failure to provide DNA

    Decompressive surgery in cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia

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    Background and purpose: Cerebral venous sinus thrombosis due to vaccine-induced im-mune thrombotic thrombocytopenia (CVST-VITT) is an adverse drug reaction occurring after severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2) vaccination. CVST-VITT patients often present with large intracerebral haemorrhages and a high proportion undergoes decompressive surgery. Clinical characteristics, therapeutic management and outcomes of CVST-VITT patients who underwent decompressive surgery are described and predictors of in- hospital mortality in these patients are explored.Methods: Data from an ongoing international registry of patients who developed CVST within 28 days of SARS-CoV- 2 vaccination, reported between 29 March 2021 and 10 May 2022, were used. Definite, probable and possible VITT cases, as defined by Pavord et al. (N Engl J Med 2021; 385: 1680–1689), were included. Results: Decompressive surgery was performed in 34/128 (27%) patients with CVST- VITT. In- hospital mortality was 22/34 (65%) in the surgical and 27/94 (29%) in the non- surgical group (p< 0.001). In all surgical cases, the cause of death was brain herniation. The highest mortality rates were found amongst patients with preoperative coma (17/18, 94% vs. 4/14, 29% in the non-comatose; p< 0.001) and bilaterally absent pupillary re-flexes (7/7, 100% vs. 6/9, 67% with unilaterally reactive pupil, and 4/11, 36% with bi-laterally reactive pupils; p= 0.023). Postoperative imaging revealed worsening of index haemorrhagic lesion in 19 (70%) patients and new haemorrhagic lesions in 16 (59%) pa-tients. At a median follow-up of 6 months, 8/10 of surgical CVST-VITT who survived ad-mission were functionally independent.Conclusions: Almost two-thirds of surgical CVST-VITT patients died during hospital ad-mission. Preoperative coma and bilateral absence of pupillary responses were associated with higher mortality rates. Survivors often achieved functional independence.Peer reviewe

    Emotional problems in preadolescents in Norway: the role of gender, ethnic minority status, and home- and school-related hassles

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    <p>Abstract</p> <p>Background</p> <p>"The gender gap" refers to a lifelong higher rate of emotional problems in girls, as compared to boys, that appears during adolescence. The gender gap is a well-replicated finding among older adolescents and is assumed to be a cross-cultural phenomenon. However, these cross-cultural studies have not investigated the gender gap in ethnic minorities but sampled ethnic majority adolescents in different countries. Some studies that investigated the gender gap across ethnic groups indirectly (by presenting emotional problem scores stratified by gender and ethnic group) indicate that the gender gap is less prominent or even absent among minorities. The aims of this study were to assess whether the gender gap is found in both majority and minority preadolescents, and to investigate whether a possible (gender and ethnic) group difference can be accounted for by differences in home or school hassles.</p> <p>Methods</p> <p>Participants were 902 preadolescent students (aged 10 to 12) from two cities in Norway. We collected self-report measures of emotional problems and home and school hassles. Using mediated moderation analysis we tested whether the interaction effect between gender and ethnic minority background on emotional problems was mediated by home or school hassles.</p> <p>Results</p> <p>The gender gap in emotional problems was restricted to ethnic majority preadolescents. School hassles but not home hassles accounted in part for this effect.</p> <p>Conclusions</p> <p>The absence of the gender gap among minority as opposed to majority preadolescents may indicate that social circumstances may postpone or hamper the emergence and magnitude of the gender gap in ethnic minority preadolescents. In this study, school hassles partly accounted for the combined gender and ethnic group differences on emotional problems. This indicates that school hassles may play a role in the higher levels of emotional problems in preadolescent minority boys and consequently the absence of a gender gap found in our minority sample.</p
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