Maternal embryonic leucine zipper kinase (MELK) regulates multipotent neural progenitor proliferation.

Maternal embryonic leucine zipper kinase (MELK) was previously identified in a screen for genes enriched in neural progenitors. Here, we demonstrate expression of MELK by progenitors in developing and adult brain and that MELK serves as a marker for self-renewing multipotent neural progenitors (MNPs) in cultures derived from the developing forebrain and in transgenic mice. Overexpression of MELK enhances (whereas knockdown diminishes) the ability to generate neurospheres from MNPs, indicating a function in self-renewal. MELK down-regulation disrupts the production of neurogenic MNP from glial fibrillary acidic protein (GFAP)-positive progenitors in vitro. MELK expression in MNP is cell cycle regulated and inhibition of MELK expression down-regulates the expression of B-myb, which is shown to also mediate MNP proliferation. These findings indicate that MELK is necessary for proliferation of embryonic and postnatal MNP and suggest that it regulates the transition from GFAP-expressing progenitors to rapid amplifying progenitors in the postnatal brain

Measuring the Benefits of Mobile Number Portability

Increasing numbers of countries require mobile telephone networks to offer mobile number portability (MNP). MNP allows customers who wish to switch mobile operator to keep their mobile numbers, avoiding the costs of switching to new numbers. Ex ante assessments suggest that MNP should reduce switching costs and strengthen competition. In this paper, we test MNP’s impact on market outcomes using international time-series cross-section data. We find that MNP significantly increases average mobile telephony retail prices and churn (a proxy for switching).

Selden's Mare Clausum: the secularisation of international law and the rise of soft imperialism

No description supplie

Quantum Plasmonics with multi-emitters: Application to adiabatic control

We construct mode-selective effective models describing the interaction of N quantum emitters (QEs) with the localised surface plasmon polaritons (LSPs) supported by a spherical metal nanoparticle (MNP) in an arbitrary geometric arrangement of the QEs. We develop a general formulation in which the field response in the presence of the nanosystem can be decomposed into orthogonal modes with the spherical symmetry as an example. We apply the model in the context of quantum information, investigating on the possibility of using the LSPs as mediators of an efficient control of population transfer between two QEs. We show that a Stimulated Raman Adiabatic Passage configuration allows such a transfer via a decoherence-free dark state when the QEs are located on the same side of the MNP and very closed to it, whereas the transfer is blocked when the emitters are positioned at the opposite sides of the MNP. We explain this blockade by the destructive superposition of all the interacting plasmonic modes

Strain-induced half-metallic ferromagnetism in zinc blende CrP/MnP superlattice: First-principles study

Using first-principles calculations within generalized gradient approximation, the electronic and magnetic properties of zinc blende (zb) CrP/MnP superlattice are investigated. The equilibrium lattice constant is calculated to be $5.33\,$\AA. The stability of ferromagnetic zb CrP/MnP superlattice against antiferromagnetism is considered and it is found that the ferromagnetic CrP/MnP superlattice is more stable than the antiferromagnetic one. It is shown that at the equilibrium lattice constant the CrP/MnP superlattice does not show any half metallicity mainly due to the minority $t_{2g}$ states of Cr and Mn. However, if strain is imposed on the CrP/MnP superlattice then the minority $t_{2g}$ electrons shift to higher energies and the proposed superlattice becomes a half-metal ferromagnet. The effect of tetragonal and orthorhombic distortions on the half metallicity of zb CrP/MnP superlattice is also discussed. It is also shown that InP-CrP/MnP/InP is a true half-metal ferromagnet. The half metallicity and magnetization of these superlattices are robust against tetragonal/ orthorhombic deformation.Comment: 5 pages, 4 figure

The impact of integrated infant and young child feeding and micronutrient powder intervention on feeding practices and anemia in children aged 6-23 months in Madagascar

This study assesses the impact of an integrated infant and young child feeding (IYCF) and micronutrient powder (MNP) intervention on children's risk of anemia and IYCF practices in Madagascar. Quantitative baseline and endline surveys were conducted in representative households with children 6-23 months from two districts, where an 18-month IYCF-MNP intervention was implemented. Relative risks comparing children's risk of anemia and maternal IYCF knowledge and practices at baseline versus endline, and also at endline among MNP-users versus non-users were estimated using log-binomial regression models. 372 and 475 children aged 6-23 months were assessed at baseline and endline respectively. Prevalence of anemia fell from 75.3% to 64.9% from baseline to endline (p = 0.002); the reduction in the risk of anemia remained significant in models adjusting for sociodemographic characteristics (ARR (95% CI): 0.86 (0.78, 0.95), p = 0.003). In endline assessments, 229 out of 474 (48.3%) of children had consumed MNPs. MNP-users had a lower risk of anemia (ARR (95% CI): 0.86 (0.74, 0.99), p = 0.04) than non-users, after controlling for child's dietary diversity and morbidity, maternal counseling by community-health-workers, and sociodemographic characteristics. Mothers interviewed at endline also had greater nutrition knowledge and were more likely to feed their children ≥4 food groups (ARR (95% CI): 2.92 (2.24, 3.80), p < 0.001), and the minimum acceptable diet (ARR (95% CI): 2.88 (2.17, 3.82), p < 0.001) than mothers interviewed at baseline. Integration of MNP into IYCF interventions is a viable strategy for improving children's consumption of micronutrients and reducing risk of anemia. The addition of MNP does not negatively impact, and may improve, IYCF practices.We are grateful to all of the mothers and children and participating communities, as well as data enumerators, and the USAID-supported SALOHI project team for the technical and financial support during the baseline and endline surveys. We also thank Jacky Raharinjatovo the PSI-Madagascar statistician for support in analyses as well as Roland Kupka, France Begin and Jennifer Marcy for their comments and feedback on this manuscript. The views expressed in this manuscript are those of the authors and do not necessarily reflect the official positions or policies of their affiliated institutions. Both the baseline and the endline surveys were funded by USAID/SALOHI. (USAID; USAID/SALOHI)Published versio

Experimental ex-vivo validation of PMMA-based bone cements loaded with magnetic nanoparticles enabling hyperthermia of metastatic bone tumors

Percutaneous vertebroplasty comprises the injection of Polymethylmethacrylate (PMMA) bone cement into vertebrae and can be used for the treatment of compression fractures of vertebrae. Metastatic bone tumors can cause such compression fractures but are not treated when injecting PMMA-based bone cement. Hyperthermia of tumors can on the other hand be attained by placing magnetic nanoparticles (MNPs) in an alternating magnetic field (AMF). Loading the PMMA-based bone cement with MNPs could both serve vertebra stabilization and metastatic bone tumor hyperthermia when subjecting this PMMA-MNP to an AMF. A dedicated pancake coil is designed with a self-inductance of 10 mu H in series with a capacitance of 0.1 mu F that acts as resonant inductor-capacitor circuit to generate the AMF. The thermal rise is appraised in beef vertebra placed at 10 cm from the AMF generating circuit using optical temperatures sensors, i. e. in the center of thePMMA-MNPbone cement, which is located in the vicinity of metastatic bone tumors in clinical applications; and in the spine, which needs to be safeguarded to high temperature exposures. Results show a temperature rise of about 7 degrees C in PMMA-MNP whereas the temperature rise in the spine remains limited to 1 degrees C. Moreover, multicycles heating of PMMA-MNP is experimentally verified, validating the technical feasibility of having PMMA-MNP as basic component for percutaneous vertebroplasty combined with hyperthermia treatment of metastatic bone tumors

Size and polydispersity effect on the magnetization of densely packed magnetic nanoparticles

The magnetic properties of densely packed magnetic nanoparticles (MNP) assemblies are investigated from Monte Carlo simulations. The case of iron oxide nanoparticles is considered as a typical example of MNP. The main focus is put on particle size and size polydispersity influences on the magnetization curve. The particles are modeled as uniformly magnetized spheres isolated one from each other by a non magnetic layer representing the organic coating. A comparison with recent experimental results on $\gamma-$Fe$_2$O$_3$ powder samples differing by their size is given.Comment: To be published in the Journal of Applied Physics, to be found at http://jap.aip.org