2,150 research outputs found

    On computational and behavioral evidence regarding Hebbian transcortical cell assemblies.

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    Pulvermuller restricts himself to an unnecessarily narrow range of evidence to support his claims. Evidence from neural modeling and behavioral experiments provides further support for an account of words encoded as transcortical cell assemblies. A cognitive neuroscience of language must include a range of methodologies (e.g., neural, computational, and behavioral) and will need to focus on the on-line processes of real-time language processing in more natural contexts

    Saturn Plasma Sources and Associated Transport Processes

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    This article reviews the different sources of plasma for Saturn’s magnetosphere, as they are known essentially from the scientific results of the Cassini-Huygens mission to Saturn and Titan. At low and medium energies, the main plasma source is the H2OH2O cloud produced by the “geyser” activity of the small satellite Enceladus. Impact ionization of this cloud occurs to produce on the order of 100 kg/s of fresh plasma, a source which dominates all the other ones: Titan (which produces much less plasma than anticipated before the Cassini mission), the rings, the solar wind (a poorly known source due to the lack of quantitative knowledge of the degree of coupling between the solar wind and Saturn’s magnetosphere), and the ionosphere. At higher energies, energetic particles are produced by energy diffusion and acceleration of lower energy plasma produced by the interchange instabilities induced by the rapid rotation of Saturn, and possibly, for the highest energy range, by contributions from the CRAND process acting inside Saturn’s magnetosphere. Discussion of the transport and acceleration processes acting on these plasma sources shows the importance of rotation-induced radial transport and energization of the plasma, and also shows how much the unexpected planetary modulation of essentially all plasma parameters of Saturn’s magnetosphere remains an unexplained mystery

    Assessment of low-dose cisplatin as a model of nausea and emesis in beagle dogs, potential for repeated administration

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    Cisplatin is a highly emetogenic cancer chemotherapy agent, which is often used to induce nausea and emesis in animal models. The cytotoxic properties of cisplatin also cause adverse events that negatively impact on animal welfare preventing repeated administration of cisplatin. In this study, we assessed whether a low (subclinical) dose of cisplatin could be utilized as a model of nausea and emesis in the dog while decreasing the severity of adverse events to allow repeated administration. The emetic, nausea-like behavior and potential biomarker response to both the clinical dose (70 mg/m2) and low dose (15 mg/m2) of cisplatin was assessed. Plasma creatinine concentrations and granulocyte counts were used to assess adverse effects on the kidneys and bone marrow, respectively. Nausea-like behavior and emesis was induced by both doses of cisplatin, but the latency to onset was greater in the low-dose group. No significant change in plasma creatinine was detected for either dose groups. Granulocytes were significantly reduced compared with baseline (P = 0.000) following the clinical, but not the low-dose cisplatin group. Tolerability of repeated administration was assessed with 4 administrations of an 18 mg/m2 dose cisplatin. Plasma creatinine did not change significantly. Cumulative effects on the granulocytes occurred, they were significantly decreased (P = 0.03) from baseline at 3 weeks following cisplatin for the 4th administration only. Our results suggest that subclinical doses (15 and 18 mg/m2) of cisplatin induce nausea-like behavior and emesis but have reduced adverse effects compared with the clinical dose allowing for repeated administration in crossover studies

    The role of immune correlates of protection on the pathway to licensure, policy decision and use of group B Streptococcus vaccines for maternal immunization: considerations from World Health Organization consultations.

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    The development of a group B Streptococcus (GBS) vaccine for maternal immunization constitutes a global public health priority, to prevent GBS-associated early life invasive disease, stillbirth, premature birth, maternal sepsis, adverse neurodevelopmental consequences, and to reduce perinatal antibiotic use. Sample size requirements for the conduct of a randomized placebo-controlled trial to assess vaccine efficacy against the most relevant clinical endpoints, under conditions of appropriate ethical standards of care, constitute a significant obstacle on the pathway to vaccine availability. Alternatively, indirect evidence of protection based on immunologic data from vaccine and sero-epidemiological studies, complemented by data from opsonophagocytic in vitro assays and animal models, could be considered as pivotal data for licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations. Based on discussions initiated by the World Health Organization we present key considerations about the potential role of correlates of protection towards an accelerated pathway for GBS vaccine licensure and wide scale use. Priority activities to support progress to regulatory and policy decision are outlined

    Lifetime economic impact of the burden of childhood stunting attributable to maternal psychosocial risk factors in 137 low/middle-income countries

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    Introduction: The first 1000 days of life is a period of great potential and vulnerability. In particular, physical growth of children can be affected by the lack of access to basic needs as well as psychosocial factors, such as maternal depression. The objectives of the present study are to: (1) quantify the burden of childhood stunting in low/middle-income countries attributable to psychosocial risk factors; and (2) estimate the related lifetime economic costs. Methods: A comparative risk assessment analysis was performed with data from 137 low/middle-income countries throughout Asia, Latin America and the Caribbean, North Africa and the Middle East, and sub-Saharan Africa. The proportion of stunting prevalence, defined as <-2 SDs from the median height for age according to the WHO Child Growth Standards, and the number of cases attributable to low maternal education, intimate partner violence (IPV), maternal depression and orphanhood were calculated. The joint effect of psychosocial risk factors on stunting was estimated. The economic impact, as reflected in the total future income losses per birth cohort, was examined. Results: Approximately 7.2 million cases of stunting in low/middle-income countries were attributable to psychosocial factors. The leading risk factor was maternal depression with 3.2 million cases attributable. Maternal depression also demonstrated the greatest economic cost at 14.5billion,followedbylowmaternaleducation(14.5 billion, followed by low maternal education (10.0 billion) and IPV (8.5billion).Thejointcostoftheseriskfactorswas8.5 billion). The joint cost of these risk factors was 29.3 billion per birth cohort. Conclusion: The cost of neglecting these psychosocial risk factors is significant. Improving access to formal secondary school education for girls may offset the risk of maternal depression, IPV and orphanhood. Focusing on maternal depression may play a key role in reducing the burden of stunting. Overall, addressing psychosocial factors among perinatal women can have a significant impact on child growth and well-being in the developing world

    Multiple courses of stereotactic re-irradiation in recurrent oligodendroglioma: a case report

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    INTRODUCTION: High grade gliomas are an insidious disease associated with an extremely poor prognosis. The role of re-irradiation for recurrent gliomas is unclear but several retrospective studies have indicated mild toxicity and modest outcomes with this regimen. With subsequent progression, it is unclear what options remain and more radiotherapy is rarely offered for fear of surpassing normal central nervous system tissue tolerance and causing significant side effects without significant benefit. CASE PRESENTATION: In this report, we describe a 37-year-old Caucasian male initially diagnosed with a grade IV oligodendroglioma, who received multiple courses of re-irradiation and experienced a survival of 10 years with minimal cognitive or neurologic deficits. CONCLUSION: Significant toxicity with multiple courses of radiation does not always occur. Re-irradiation should be considered in a salvage setting

    Singular charge fluctuations at a magnetic quantum critical point

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    Strange metal behavior is ubiquitous in correlated materials, ranging from cuprate superconductors to bilayer graphene, and may arise from physics beyond the quantum fluctuations of a Landau order parameter. In quantum-critical heavy-fermion antiferromagnets, such physics may be realized as critical Kondo entanglement of spin and charge and probed with optical conductivity. We present terahertz time-domain transmission spectroscopy on molecular beam epitaxy–grown thin films of YbRh2Si2, a model strange-metal compound. We observed frequency over temperature scaling of the optical conductivity as a hallmark of beyond-Landau quantum criticality. Our discovery suggests that critical charge fluctuations play a central role in the strange metal behavior, elucidating one of the long-standing mysteries of correlated quantum matter.Financial support for this work was provided by the European Research Council (ERC Advanced Grant 227378), the U.S. Army Research Office (ARO W911NF-14-1-0496), the Austrian Science Fund (FWF W1243, P29279-N27, and P29296-N27), and the European Union’s Horizon 2020 research and innovation programme (grant agreement No 824109 – EMP). X.L. and J.K. acknowledge financial support from the National Science Foundation (NSF MRSEC DMR-1720595) and the ARO (W911NF-17-1-0259). Q.S. acknowledges financial support from the NSF (DMR-1920740), the Robert A.Welch Foundation (C-1411), and the ARO (W911NF-14-1-0525), and hospitality of the University of California at Berkeley, the Aspen Center for Physics (NSF grant PHY-1607611), and the Los Alamos National Laboratory (via a Ulam Scholarship from the Center for Nonlinear Studies). This work has also been supported by an InterDisciplinary Excellence Award (IDEA) from Rice University (Q.S., E.R., J.K., S.P.)

    The relationship between the systemic inflammatory response and survival in patients with transitional cell carcinoma of the urinary bladder

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    The relationship between tumour stage, grade, elevated C-reactive protein concentration (<10/>10 mg l−1), adjuvant therapy and survival was examined in patients with biopsy proven bladder cancer (n=105). On multivariate analysis stage (HR 3.37, 95% CI 1.37–8.29, P=0.008), grade (HR 2.01, 95% CI 1.14–3.57, P=0.017) and preoperative C-reactive protein (HR 3.31, 95% CI 1.09–10.09, P=0.035) were independently associated with cancer-specific survival
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