1,346 research outputs found

    On Scaling Solutions with a Dissipative Fluid

    Full text link
    We study the asymptotic behaviour of scaling solutions with a dissipative fluid and we show that, contrary to recent claims, the existence of stable accelerating attractor solution which solves the `energy' coincidence problem depends crucially on the chosen equations of state for the thermodynamical variables. We discuss two types of equations of state, one which contradicts this claim, and one which supports it.Comment: 8 pages and 5 figures; to appear in Class. Quantum Gra

    Social robots as psychometric tools for cognitive assessment: a pilot test

    Get PDF
    Recent research demonstrated the benefits of employing robots as therapeutic assistants and caregivers, but very little is known on the use of robots as a tool for psychological assessment. Socially capable robots can provide many advantages to diagnostic practice: engage people, guarantee standardized administration and assessor neutrality, perform automatic recording of subject behaviors for further analysis by practitioners. In this paper, we present a pilot study on testing people’s cognitive functioning via social interaction with a humanoid robot. To this end, we programmed a social robot to administer a psychometric tool for detecting Mild Cognitive Impairment, a risk factor for dementia, implementing the first prototype of robotic assistant for mass screening of elderly population. Finally, we present a pilot test of the robotic procedure with healthy adults that show promising results of the robotic test, also compared to its traditional paper version

    An eclipsing binary distance to the Large Magellanic Cloud accurate to 2 per cent

    Full text link
    In the era of precision cosmology it is essential to determine the Hubble Constant with an accuracy of 3% or better. Currently, its uncertainty is dominated by the uncertainty in the distance to the Large Magellanic Cloud (LMC) which as the second nearest galaxy serves as the best anchor point of the cosmic distance scale. Observations of eclipsing binaries offer a unique opportunity to precisely and accurately measure stellar parameters and distances. The eclipsing binary method was previously applied to the LMC but the accuracy of the distance results was hampered by the need to model the bright, early-type systems used in these studies. Here, we present distance determinations to eight long-period, late- type eclipsing systems in the LMC composed of cool giant stars. For such systems we can accurately measure both the linear and angular sizes of their components and avoid the most important problems related to the hot early-type systems. Our LMC distance derived from these systems is demonstrably accurate to 2.2 % (49.97 +/- 0.19 (statistical) +/- 1.11 (systematic) kpc) providing a firm base for a 3 % determination of the Hubble Constant, with prospects for improvement to 2 % in the future.Comment: 34 pages, 5 figures, 13 tables, published in the Nature, a part of our data comes from new unpublished OGLE-IV photometric dat

    Reducing bias in auditory duration reproduction by integrating the reproduced signal

    Get PDF
    Duration estimation is known to be far from veridical and to differ for sensory estimates and motor reproduction. To investigate how these differential estimates are integrated for estimating or reproducing a duration and to examine sensorimotor biases in duration comparison and reproduction tasks, we compared estimation biases and variances among three different duration estimation tasks: perceptual comparison, motor reproduction, and auditory reproduction (i.e. a combined perceptual-motor task). We found consistent overestimation in both motor and perceptual-motor auditory reproduction tasks, and the least overestimation in the comparison task. More interestingly, compared to pure motor reproduction, the overestimation bias was reduced in the auditory reproduction task, due to the additional reproduced auditory signal. We further manipulated the signal-to-noise ratio (SNR) in the feedback/comparison tones to examine the changes in estimation biases and variances. Considering perceptual and motor biases as two independent components, we applied the reliability-based model, which successfully predicted the biases in auditory reproduction. Our findings thus provide behavioral evidence of how the brain combines motor and perceptual information together to reduce duration estimation biases and improve estimation reliability

    Cisplatin neurotoxicity in the treatment of metastatic germ cell tumour: time course and prognosis

    Get PDF
    In order to ascertain the incidence and prognosis of cisplatin-induced neurotoxicity in testis cancer patients undergoing combination chemotherapy, 29 patients with metastatic disease were studied prospectively. Assessments included enquiry into neurological symptoms, measurement of sural nerve sensory action potential and conduction velocity, and vibration threshold in the left big toe. At the end of chemotherapy (3 to 4 cycles) only 3 out of 26 (11%) patients had paraesthesiae, but 3 months later the proportion rose to 65%. Resolution occurred in the majority over the ensuing 12 months so that only 17% had persistent symptoms. None of the 11 patients treated with 3 cycles of chemotherapy had persisting symptoms. Vibration thresholds showed a significant deterioration during chemotherapy (P = 0.032), further deterioration in the 3 months following chemotherapy (P = 0.009) and significant improvement between 3 and 12 months after chemotherapy (P = 0.038). Sural nerve sensory action potentials and conduction velocities were unhelpful.© 2001 Cancer Research Campaignhttp://www.bjcancer.co

    Lung adenocarcinoma presenting as a solitary gingival metastasis: a case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>Gingival metastases are very rare and generally occur in disseminated tumors. We report a case of solitary gingival metastasis of lung cancer.</p> <p>Case presentation</p> <p>We report the case of a 74-year-old asymptomatic Caucasian woman affected by a rapidly growing, painless gingival swelling. Histopathologic examination of the excisional biopsy showed metastasis of poorly differentiated thyroid transcription factor 1-positive adenocarcinoma. A total-body computed tomographic scan revealed a tumor of the right lung lower lobe with ipsilateral, mediastinal lymph node swelling. Moreover, bone scintigraphy revealed no bone metastases. No other metastases were found, so we planned a multi-modal therapeutic approach with a curative intent. However, the tumor proved to be intrinsically resistant and highly aggressive.</p> <p>Conclusion</p> <p>The presentation of solitary gingival metastasis is exceptional. In view of its rapid clinical evolution, our case confirms that gingival metastasis is an important prognostic factor. This behavior raises the question whether the poor prognosis for patients with tumors with oral metastases depends on its diffuse spread or on its highly malignant nature.</p

    A comprehensive 1000 Genomes-based genome-wide association meta-analysis of coronary artery disease

    Get PDF
    Existing knowledge of genetic variants affecting risk of coronary artery disease (CAD) is largely based on genome-wide association studies (GWAS) analysis of common SNPs. Leveraging phased haplotypes from the 1000 Genomes Project, we report a GWAS meta-analysis of 185 thousand CAD cases and controls, interrogating 6.7 million common (MAF>0.05) as well as 2.7 million low frequency (0.005<MAF<0.05) variants. In addition to confirmation of most known CAD loci, we identified 10 novel loci, eight additive and two recessive, that contain candidate genes that newly implicate biological processes in vessel walls. We observed intra-locus allelic heterogeneity but little evidence of low frequency variants with larger effects and no evidence of synthetic association. Our analysis provides a comprehensive survey of the fine genetic architecture of CAD showing that genetic susceptibility to this common disease is largely determined by common SNPs of small effect siz

    Yersinia enterocolitica Targets Cells of the Innate and Adaptive Immune System by Injection of Yops in a Mouse Infection Model

    Get PDF
    Yersinia enterocolitica (Ye) evades the immune system of the host by injection of Yersinia outer proteins (Yops) via a type three secretion system into host cells. In this study, a reporter system comprising a YopE-β-lactamase hybrid protein and a fluorescent staining sensitive to β-lactamase cleavage was used to track Yop injection in cell culture and in an experimental Ye mouse infection model. Experiments with GD25, GD25-β1A, and HeLa cells demonstrated that β1-integrins and RhoGTPases play a role for Yop injection. As demonstrated by infection of splenocyte suspensions in vitro, injection of Yops appears to occur randomly into all types of leukocytes. In contrast, upon infection of mice, Yop injection was detected in 13% of F4/80+, 11% of CD11c+, 7% of CD49b+, 5% of Gr1+ cells, 2.3% of CD19+, and 2.6% of CD3+ cells. Taking the different abundance of these cell types in the spleen into account, the highest total number of Yop-injected cells represents B cells, particularly CD19+CD21+CD23+ follicular B cells, followed by neutrophils, dendritic cells, and macrophages, suggesting a distinct cellular tropism of Ye. Yop-injected B cells displayed a significantly increased expression of CD69 compared to non-Yop-injected B cells, indicating activation of these cells by Ye. Infection of IFN-γR (receptor)- and TNFRp55-deficient mice resulted in increased numbers of Yop-injected spleen cells for yet unknown reasons. The YopE-β-lactamase hybrid protein reporter system provides new insights into the modulation of host cell and immune responses by Ye Yops

    Identifying Resistance Mechanisms against Five Tyrosine Kinase Inhibitors Targeting the ERBB/RAS Pathway in 45 Cancer Cell Lines

    Get PDF
    Because of the low overall response rates of 10-47% to targeted cancer therapeutics, there is an increasing need for predictive biomarkers. We aimed to identify genes predicting response to five already approved tyrosine kinase inhibitors. We tested 45 cancer cell lines for sensitivity to sunitinib, erlotinib, lapatinib, sorafenib and gefitinib at the clinically administered doses. A resistance matrix was determined, and gene expression profiles of the subsets of resistant vs. sensitive cell lines were compared. Triplicate gene expression signatures were obtained from the caArray project. Significance analysis of microarrays and rank products were applied for feature selection. Ninety-five genes were also measured by RT-PCR. In case of four sunitinib resistance associated genes, the results were validated in clinical samples by immunohistochemistry. A list of 63 top genes associated with resistance against the five tyrosine kinase inhibitors was identified. Quantitative RT-PCR analysis confirmed 45 of 63 genes identified by microarray analysis. Only two genes (ANXA3 and RAB25) were related to sensitivity against more than three inhibitors. The immunohistochemical analysis of sunitinib-treated metastatic renal cell carcinomas confirmed the correlation between RAB17, LGALS8, and EPCAM and overall survival. In summary, we determined predictive biomarkers for five tyrosine kinase inhibitors, and validated sunitinib resistance biomarkers by immunohistochemistry in an independent patient cohort. © 2013 Pénzváltó et al

    Shift Work Disorder in Nurses – Assessment, Prevalence and Related Health Problems

    Get PDF
    BACKGROUND: This study investigates the prevalence of symptoms of shift work disorder in a sample of nurses, and its association to individual, health and work variables. METHODOLOGY/PRINCIPAL FINDINGS: We investigated three different shift work disorder assessment procedures all based on current diagnostic criteria and employing symptom based questions. Crude and adjusted logistic regression analyses were performed with symptoms of shift work disorder as the dependent variable. Participants (n = 1968) reported age, gender, work schedule, commuting time, weekly work hours, children in household, number of nights and number of shifts separated by less than 11 hours worked the last year, use of bright light therapy, melatonin and sleep medication, and completed the Bergen Insomnia Scale, Epworth Sleepiness Scale, Global Sleep Assessment Questionnaire, Diurnal Scale, Revised Circadian Type Inventory, Dispositional Resilience (Hardiness) Scale--Revised, Fatigue Questionnaire, questions about alcohol and caffeine consumption, as well as the Hospital Anxiety and Depression Scale. CONCLUSIONS/SIGNIFICANCE: Prevalence rates of symptoms of shift work disorder varied from 32.4-37.6% depending on the assessment method and from 4.8-44.3% depending on the work schedule. Associations were found between symptoms of shift work disorder and age, gender, circadian type, night work, number of shifts separated by less than 11 hours and number of nights worked the last year, insomnia and anxiety. The different assessment procedures yielded similar results (prevalence and logistic regression analyses). The prevalence of symptoms indicative of shift work disorder was high. We argue that three symptom-based questions used in the present study adequately assess shift work disorder in epidemiological studies
    corecore