1,995 research outputs found

    T he Effects of Loose Parts and Nature-Based Play on Creativity in the Montessori Early Childhood (3-6 year old) Classroom

    Get PDF
    The purpose of this research was to determine if the addition of natural loose parts, or manipulatives, to the outdoor play yard would increase creativity in the classroom. This study took place in a private Montessori school with 14 children ages 3 to 6 years old over a five-week period. Various methods were used to gather information to determine any change in creativity. Observations of creative behaviors, concentration (state of flow), and spontaneous collaboration were collected as well as drawing tests for creative thinking, and samples of creative writing and artwork. The results of the study found that the loose parts did not increase creativity in the classroom. However, the addition of the loose parts did correlate with an increase in collaboration, imaginative play and a possible increase in concentration. Suggestions for further research include extending the amount of time the study took place, and focusing on one age rather than a mixed aged grouping

    Genistein-induced mir-23b expression inhibits the growth of breast cancer cells

    Get PDF
    Aim of the study: Genistein, an isoflavonoid, plays roles in the inhibition of protein tyrosine kinase phosphorylation, induction of apoptosis, and cell differentiation in breast cancer. This study aims to induce cellular stress by exposing genistein to determine alterations of miRNA expression profiles in MCF-7 cells. Material and methods: XTT assay and trypan blue dye exclusion assays were performed to examine the cytotoxic effects of genistein treatment. Expressions of miRNAs were quantified using Real-Time Online RT-PCR. Results: The IC50 dose of genistein was 175 μM in MCF-7 cell, line and the cytotoxic effect of genistein was detected after 48 hours. miR-23b was found to be up-regulated 56.69 fold following the treatment of genistein. It was found that miR-23b was up-regulated for MCF-7 breast cancer cells after genistein treatment. Conclusions: Up-regulated ex-expression of miR-23b might be a putative biomarker for use in the therapy of breast cancer patients. miR-23b up-regulation might be important in terms of response to genistein. © 2015, Termedia Publishing House Ltd. All rights reserved

    The Effects of Low and Moderate Dose Caffeine Supplementation on Upper and Lower Body Maximal Voluntary Concentric and Eccentric Muscle Force

    Get PDF
    Despite the growing quantity of literature exploring the effect of caffeine on muscular strength, there is a dearth of data that directly explores differences in erogenicity between upper and lower body musculature and the dose response effect. The present study sought to investigate the effects of low and moderate dose caffeine on the maximal voluntary strength of the elbow flexors and knee extensors. Ten non-specifically strength trained, recreationally active participants (21 ± 0.3 yrs) completed the study. Using a randomised, counterbalanced and double blind approach, isokinetic concentric and eccentric strength was measured at 60 and 180 deg/s following administration of a placebo, 3 mg・kg−1 body mass caffeine and 6 mg・kg−1 body mass caffeine. There was no effect of caffeine on the maximal voluntary concentric and eccentric strength of the elbow flexors, or the eccentric strength of the knee extensors. Both 3 and 6 mg・kg−1 body mass caffeine caused a significant increase in peak concentric force of the knee extensors at 180 deg/s. No difference was apparent between the two concentrations. Only 6 mg・kg−1 body mass caused an increase in peak concentric force during repeated contractions. The results infer that the effective caffeine concentration to evoke improved muscle performance may be related to muscle mass and contraction type. The present work indicates that relatively low dose caffeine treatment may be effective for improving lower body muscular strength, but may have little benefit for the strength of major muscular groups of the upper body.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    Local Bone Marrow Renin-Angiotensin System and Atherosclerosis

    Get PDF
    Local hematopoietic bone marrow (BM) renin-angiotensin system (RAS) affects the growth, production, proliferation differentiation, and function of hematopoietic cells. Angiotensin II (Ang II), the dominant effector peptide of the RAS, regulates cellular growth in a wide variety of tissues in pathobiological states. RAS, especially Ang II and Ang II type 1 receptor (AT1R), has considerable proinflammatory and proatherogenic effects on the vessel wall, causing progression of atherosclerosis. Recent investigations, by analyzing several BM chimeric mice whose BM cells were positive or negative for AT1R, disclosed that AT1R in BM cells participates in the pathogenesis of atherosclerosis. Therefore, AT1R blocking not only in vascular cells but also in the BM could be an important therapeutic approach to prevent atherosclerosis. The aim of this paper is to review the function of local BM RAS in the pathogenesis of atherosclerosis

    An Inexpensive Flying Robot Design for Embodied Robotics Research

    Get PDF
    Flying insects are capable of a wide-range of flight and cognitive behaviors which are not currently understood. The replication of these capabilities is of interest to miniaturized robotics, because they share similar size, weight, and energy constraints. Currently, embodiment of insect behavior is primarily done on ground robots which utilize simplistic sensors and have different constraints to flying insects. This limits how much progress can be made on understanding how biological systems fundamentally work. To address this gap, we have developed an inexpensive robotic solution in the form of a quadcopter aptly named BeeBot. Our work shows that BeeBot can support the necessary payload to replicate the sensing capabilities which are vital to bees' flight navigation, including chemical sensing and a wide visual field-of-view. BeeBot is controlled wirelessly in order to process this sensor data off-board; for example, in neural networks. Our results demonstrate the suitability of the proposed approach for further study of the development of navigation algorithms and of embodiment of insect cognition

    Disks Surviving the Radiation Pressure of Radio Pulsars

    Full text link
    The radiation pressure of a radio pulsar does not necessarily disrupt a surrounding disk. The position of the inner radius of a thin disk around a neutron star can be estimated by comparing the electromagnetic energy density generated by the neutron star with the kinetic energy density of the disk. Inside the light cylinder, the near zone electromagnetic field is essentially the dipole magnetic field, and the inner radius is the conventional Alfven radius. Far outside the light cylinder, in the radiation zone, E=BE=B and the electromagnetic energy density is /c1/r2/c \propto 1/r^2 where SS is the Poynting vector. Shvartsman (1970) argued that a stable equilibrium can not be found in the radiative zone because the electromagnetic energy density dominates over the kinetic energy density, with the relative strength of the electromagnetic stresses increasing with radius. In order to check whether this is true also near the light cylinder, we employ global electromagnetic field solutions for rotating oblique magnetic dipoles (Deutsch 1955). Near the light cylinder the electromagnetic energy density increases steeply enough with decreasing rr to balance the kinetic energy density at a stable equilibrium. The transition from the near zone to the radiation zone is broad. The radiation pressure of the pulsar can not disrupt the disk for values of the inner radius up to about twice the light cylinder radius if the rotation axis and the magnetic axis are orthogonal. This allowed range beyond the light cylinder extends much further for small inclination angles. We discuss implications of this result for accretion driven millisecond pulsars and young neutron stars with fallback disks.Comment: Accepted by Astrophysical Journal, final version with a minor correctio

    Can Thin Disks Produce Anomalous X-Ray Pulsars?

    Get PDF
    We investigate whether young neutron stars with fall-back disks can produce Anomalous X-Ray Pulsars (AXPs) within timescales indicated by the ages of associated supernova remnants. The system passes through a propeller stage before emerging as an AXP or a radio pulsar. The evolution of the disk is described by a diffusion equation which has self-similar solutions with either angular momentum or total mass of the disk conserved. We associate these two types of solutions with accretor and propeller regimes, respectively. Our numerical calculations of thin disk models with changing inner radius take into account the super-critical accretion at the early stages, and electron scattering and bound-free opacities with rich metal content. Our results show that, assuming a fraction of the mass inflow is accreted onto the neutron star, the fall-back disk scenario can produce AXPs for acceptable parameters.Comment: 16 pages, 4 Figures, to be published in Astrophysical Journal Vol. 599, Dec. 1
    corecore