255 research outputs found

    Longitudinal associations between executive functions and metacognitive monitoring in 5- to 8-year-olds

    Get PDF
    Pronounced developmental progression during the transition to formal schooling can be found in executive functions (EF) and metacognition (MC). However, it is still unclear whether and how EF and MC influence each other during this transition. Previous research with young children suggests that inhibition may be a prerequisite for monitoring skills. Thus, the present longitudinal study investigated the association between the common subcomponents of EF (inhibition, working memory, and shifting) assessed in kindergarten (T1) and metacognitive monitoring assessed in 2nd grade (T2) in a sample of N = 84 children. In line with our hypothesis, the results revealed a significant link only between the EF subcomponent inhibition and later metacognitive monitoring. More precisely, children with better inhibition skills in kindergarten showed less overconfident monitoring in elementary school. Interestingly, the longitudinal relationship between inhibition and monitoring was not bidirectional. The findings indicate an essential role of early inhibition skills regarding emerging and developing elementary school children’s monitoring skills

    POSITION AND ALIGNMENT OF FLEX ZONES IN RUNNING SHOES

    Get PDF
    The right position and alignment of forefoot flexibility zones in running shoes represents a precondition to avoid overuse injuries of the foot and leg. The goal of this study was to determine foot anthropometries, in order to set up construction guidelines for the positioning and alignment of the flex zones in running shoes. The foot anthropometries of 471 runners were measured with a 2D scanning system under static conditions. The metatarsal-length-indices (MU) were calculated for each ray. The calculated MUs do not indicate the necessity for a grading pattern regarding different shoe sizes, gender dimorphism and different regions. To consider the anthropometrical variance of the MUs it is suggested to apply flex zones instead of only flex grooves. The results suggest the application of a transversal, a longitudinal and a diagonal flex zone in running shoes

    The continuous wave electron paramagnetic resonance experiment revisited

    Get PDF
    When the modulation frequency used in continuous wave electron paramagnetic resonance (cw EPR) spectroscopy exceeds the linewidth, modulation sidebands appear in the spectrum. It is shown theoretically and experimentally that these sidebands are actually multiple photon transitions, σ++k × π, where one microwave (mw) σ+ photon is absorbed from the mw radiation field and an arbitrary number k of radio frequency (rf) π photons are absorbed from or emitted to the modulation rf field. Furthermore, it is demonstrated that both the derivative shape of the lines in standard cw EPR spectra and the distortions due to overmodulation are caused by the unresolved sideband pattern of these lines. The single-photon transition does not even give a contribution to the first-harmonic cw EPR signal. Multiple photon transitions are described semiclassically in a toggling frame and their existence is proven using second quantization. With the toggling frame approach and perturbation theory an effective Hamiltonian for an arbitrary sideband transition is derived. Based on the effective Hamiltonians an expression for the steady-state density operator in the singly rotating frame is derived, completely describing all sidebands in all modulation frequency harmonics of the cw EPR signal. The relative intensities of the sidebands are found to depend in a very sensitive way on the actual rf amplitude and the saturation of single sidebands is shown to depend strongly on the effective field amplitude of the multiple photon transitions. By comparison with the analogous solutions for frequency-modulation EPR it is shown that the field-modulation and the frequency-modulation technique are not equivalent. The experimental data fully verify the theoretical predictions with respect to intensities and lineshapes. © 2003 Elsevier Science (USA). All rights reserved

    Applications of π-photon-induced transparency in two-frequency pulse electron paramagnetic resonance experiments

    Get PDF
    Bichromatic pulses were demonstrated to substitute the second mw source both in stimulated soft electron spin echo envelope modulation (SS-ESEEM) and four-pulse double electron-electron resonance (DEER) experiments. As such, the results were compared to those obtained using traditional techniques. The behavior of bichromatic pulses which fulfill the transparency or near-transparency condition was investigated, and recommendations for obtaining optimum results were given

    Multiphoton Transitions in a Spin System Driven by Strong Bichromatic Field

    Full text link
    EPR transient nutation spectroscopy is used to measure the effective field (Rabi frequency) for multiphoton transitions in a two-level spin system bichromatically driven by a transverse microwave (MW) field and a longitudinal radio-frequency (RF) field. The behavior of the effective field amplitude is examined in the case of a relatively strong MW field, when the derivation of the effective Hamiltonian cannot be reduced to first-order perturbation theory in w_{1} / w_{rf} (w_{1} is the microwave Rabi frequency, w_{rf} is the RF frequency). Experimental results are consistently interpreted by taking into account the contributions of second and third order in w_{1} / w_{rf} evaluated by Krylov-Bogolyubov-Mitropolsky averaging. In the case of inhomogeneously broadened EPR line, the third-order correction modifies the nutation frequency, while the second-order correction gives rise to a change in the nutation amplitude due to a Bloch-Siegert shift.Comment: 7 pages, 6 figure

    Macropinocytotic uptake and infection of human epithelial cells with species B2 adenovirus type 35

    Full text link
    The human adenovirus serotype 35 (HAdV-35, short Ad35) causes kidney and urinary tract infections, and infects respiratory organs of immunocompromised individuals. Unlike other adenoviruses, Ad35 has a low seroprevalence which makes Ad35-based vectors promising candidates for gene therapy. Ad35 utilizes CD46 and integrins as receptors for infection of epithelial and hematopoietic cells. Here, we show that infectious entry of Ad35 into HeLa, human kidney HK-2 cells and normal human lung fibroblasts strongly depended on CD46 and integrins but not heparan sulfate, and variably required the large GTPase dynamin. Ad35 infections were independent of expression of the carboxy-terminal domain of AP180 which effectively blocks clathrin-mediated uptake. Ad35 infections were inhibited by small chemicals against the serine/threonine kinase Pak1 (p21-activated kinase), protein kinase C (PKC), sodium-proton exchangers, actin and acidic organelles. Remarkably, the F-actin inhibitor jasplakinolide, the Pak1 inhibitor IPA-3 or the sodium-proton exchange inhibitor EIPA blocked the endocytic uptake of Ad35. Dominant-negative proteins or small interfering RNAs against factors driving macropinocytosis, including the small GTPase Rac1, Pak1 or the Pak1 effector C-terminal binding protein 1 (CtBP1) potently inhibited Ad35 infection. Confocal laser scanning microscopy, electron microscopy and live cell imaging showed that Ad35 colocalized with fluid phase markers in large endocytic structures that were positive for CD46, alpha v integrins and also CtBP1. Our results extend earlier observations with HAdV-3 (Ad3), and establish macropinocytosis as an infectious pathway for species B human adenoviruses in epithelial and hematopoietic cells

    What is the effect of sensory discrimination training on chronic low back pain? A systematic review

    Get PDF
    Sensory discrimination training (SDT) for people with chronic low back pain (CLBP) is a novel approach based on theories of the cortical reorganization of the neural system. SDT aims to reverse cortical reorganization, which is observed in chronic pain patients. SDT is still a developing therapeutic approach and its effects have not been systematically reviewed. The aim of this systematic review was to evaluate if SDT decreases pain and improves function in people with CLBP. Methods A systematic review was performed on the available literature to evaluate the effects of SDT. Randomised controlled trials compared the effectiveness of SDT on pain and function in people with CLBP with the effectiveness of other physiotherapy interventions, no treatment, or sham therapy. The methodological quality of the included studies and the clinical relevance of reported treatment effects were investigated. Results The original search revealed 42 records of which 6 fulfilled the inclusion criteria. The majority of studies showed that SDT caused statistically significant improvements in pain and function, but only two studies reported clinically relevant improvements. The applied SDT varied considerably with regard to dosage and content. The methodological quality of the included studies also varied, which hampered the comparability of results. Conclusions Although SDT seems to improve pain and function in people with CLBP, study limitations render firm conclusions unsafe. Future studies should pay closer attention to power and sample selection as well as to the content and dosage of the SDT intervention. We recommend a large, well-powered, prospective randomized control study that uses a standardized SDT approach to address the hypothesis that SDT causes clinically relevant improvements in pain and function.BioMed Central open acces

    Anterior thoracolumbar column reconstruction with the vertebral body stent-safety and efficacy.

    Get PDF
    PURPOSE The aim of this study was to assess safety and efficacy of vertebral body stenting (VBS) by analyzing (1) radiographic outcome, (2) clinical outcome, and (3) perioperative complications in patients with vertebral compression fractures treated with VBS at minimum 6-month follow-up. METHODS In this retrospective cohort study, 78 patients (61 ± 14 [21-90] years; 67% female) who have received a vertebral body stent due to a traumatic, osteoporotic or metastatic thoracolumbar compression fracture at our hospital between 2012 and 2020 were included. Median follow-up was 0.9 years with a minimum follow-up of 6 months. Radiographic and clinical outcome was analyzed directly, 6 weeks, 12 weeks, 6 months postoperatively, and at last follow-up. RESULTS Anterior vertebral body height of all patients improved significantly by mean 6.2 ± 4.8 mm directly postoperatively (p < 0.0001) and remained at 4.3 ± 5.1 mm at last follow-up compared to preoperatively (p < 0.0001). The fracture kyphosis angle of all patients improved significantly by mean 5.8 ± 6.9 degrees directly postoperatively (p < 0.0001) and remained at mean 4.9 ± 6.9 degrees at last follow-up compared to preoperatively (p < 0.0001). The segmental kyphosis angle of all patients improved significantly by mean 7.1 ± 7.6 degrees directly postoperatively (p < 0.0001) and remained at mean 2.8 ± 7.8 degrees at last follow-up compared to preoperatively (p = 0.03). Back pain was ameliorated from a preoperative median Numeric Rating Scale value of 6.5 to 3.0 directly postoperatively and further bettered to 1.0 six months postoperatively (p = 0.0001). Revision surgery was required in one patient after 0.4 years. CONCLUSION Vertebral body stenting is a safe and effective treatment option for osteoporotic, traumatic and metastatic compression fractures

    Regulating Assisted Reproduction in Canada, Switzerland, and the USA: Comparing the Judicialization of Policy-making

    Full text link
    This article analyses the extent to which courts shape policies for assisted reproduction. While the USA is considered to be the most litigious country, Canada has observed a growing involvement of the courts from the 1980’s onward, and Switzerland is characterized by a modest degree of judicialization. Based on national patterns, we would expect litigation and court impact to vary across these three countries. As this paper demonstrates, policy-process specific variables such as the structure of policy conflicts, the novelty of regulation, self-regulation by key stakeholders, and the policies in place better explain the variation in the judicialization of policy-making

    Regional Fluid-Attenuated Inversion Recovery (FLAIR) at 7 Tesla correlates with amyloid beta in hippocampus and brainstem of cognitively normal elderly subjects

    Get PDF
    Background: Accumulation of amyloid beta (Aβ) may occur during healthy aging and is a risk factor for Alzheimer Disease (AD). While individual Aβ-accumulation can be measured non-invasively using Pittsburgh Compund-B positron emission tomography (PiB-PET), Fluid-attenuated inversion recovery (FLAIR) is a Magnetic Resonance Imaging (MRI) sequence, capable of indicating heterogeneous age-related brain pathologies associated with tissue-edema. In the current study cognitively normal elderly subjects were investigated for regional correlation of PiB- and FLAIR intensity. Methods: Fourteen healthy elderly subjects without known history of cognitive impairment received 11C-PiB-PET for estimation of regional Aβ-load. In addition, whole brain T1-MPRAGE and FLAIR-MRI sequences were acquired at high field strength of 7 Tesla (7T). Volume-normalized intensities of brain regions were assessed by applying an automated subcortical segmentation algorithm for spatial definition of brain structures. Statistical dependence between FLAIR- and PiB-PET intensities was tested using Spearman's rank correlation coefficient (rho), followed by Holm–Bonferroni correction for multiple testing. Results: Neuropsychological testing revealed normal cognitive performance levels in all participants. Mean regional PiB-PET and FLAIR intensities were normally distributed and independent. Significant correlation between volume-normalized PiB-PET signals and FLAIR intensities resulted for Hippocampus (right: rho = 0.86; left: rho = 0.84), Brainstem (rho = 0.85) and left Basal Ganglia vessel region (rho = 0.82). Conclusions: Our finding of a significant relationship between PiB- and FLAIR intensity mainly observable in the Hippocampus and Brainstem, indicates regional Aβ associated tissue-edema in cognitively normal elderly subjects. Further studies including clinical populations are necessary to clarify the relevance of our findings for estimating individual risk for age-related neurodegenerative processes such as AD
    • …
    corecore