Measurement of thin film magnetostriction using field-dependent atomic force microscopy

Measurement of thin film magnetostriction is a challenging task, as magnetostrictive material deformations in parts per million, in conjunction with materials at small dimensions, require high precision, often with dedicated set-ups, for reproducible results. We have developed a novel approach employing a commercial atomic force microscope (AFM) with attached electromagnets. Magnetostriction measurements are demonstrated on 50 - 500 nm thick Fe81Al19 films sputter deposited directly on high aspect ratio commercial AFM micro-cantilevers. A magnetostrictive deflection of the cantilever bimorph translates into a deflection force acting in a contact mode measurement, which is interpreted and recorded as a change in height. For determination of the magnetostriction coefficient, we have developed a modified version of the equation for the magnetostrictive deflection of a cantilever bimorph by Guerrero and Wetherhold, taking into account long-range attractive forces acting during contact mode AFM measurements in air. The sub-atomic precision of the AFM, combined with the widespread availability of all components and the simple set-up, makes the measurement of magnetostriction on films of just a few tens of nanometers thickness easily accessible.H2020-MSCA-ITN-2014 SELECTA (grant agreement no. 642642 of the European Commission

The Three Hundred project: a large catalogue of theoretically modelled galaxy clusters for cosmological and astrophysical applications

We introduce the The Three Hundred project, an endeavour to model 324 large galaxy clusters with full-physics hydrodynamical re-simulations. Here we present the dataset and study the differences to observations for fundamental galaxy cluster properties and scaling relations. We find that the modelled galaxy clusters are generally in reasonable agreement with observations with respect to baryonic fractions and gas scaling relations at redshift z = 0. However, there are still some (model-dependent) differences, such as central galaxies being too massive, and galaxy colours (g − r) being bluer (about 0.2 dex lower at the peak position) than in observations. The agreement in gas scaling relations down to 1013 h−1M⊙ between the simulations indicates that particulars of the sub-grid modelling of the baryonic physics only has a weak influence on these relations. We also include – where appropriate – a comparison to three semi-analytical galaxy formation models as applied to the same underlying dark matter only simulation. All simulations and derived data products are publicly available

Large-Scale Phenotyping of an Accurate Genetic Mouse Model of JNCL Identifies Novel Early Pathology Outside the Central Nervous System

Cln3Δex7/8 mice harbor the most common genetic defect causing juvenile neuronal ceroid lipofuscinosis (JNCL), an autosomal recessive disease involving seizures, visual, motor and cognitive decline, and premature death. Here, to more thoroughly investigate the manifestations of the common JNCL mutation, we performed a broad phenotyping study of Cln3Δex7/8 mice. Homozygous Cln3Δex7/8 mice, congenic on a C57BL/6N background, displayed subtle deficits in sensory and motor tasks at 10–14 weeks of age. Homozygous Cln3Δex7/8 mice also displayed electroretinographic changes reflecting cone function deficits past 5 months of age and a progressive decline of retinal post-receptoral function. Metabolic analysis revealed increases in rectal body temperature and minimum oxygen consumption in 12–13 week old homozygous Cln3Δex7/8mice, which were also seen to a lesser extent in heterozygous Cln3Δex7/8 mice. Heart weight was slightly increased at 20 weeks of age, but no significant differences were observed in cardiac function in young adults. In a comprehensive blood analysis at 15–16 weeks of age, serum ferritin concentrations, mean corpuscular volume of red blood cells (MCV), and reticulocyte counts were reproducibly increased in homozygous Cln3Δex7/8 mice, and male homozygotes had a relative T-cell deficiency, suggesting alterations in hematopoiesis. Finally, consistent with findings in JNCL patients, vacuolated peripheral blood lymphocytes were observed in homozygous Cln3Δex7/8 neonates, and to a greater extent in older animals. Early onset, severe vacuolation in clear cells of the epididymis of male homozygous Cln3Δex7/8 mice was also observed. These data highlight additional organ systems in which to study CLN3 function, and early phenotypes have been established in homozygous Cln3Δex7/8 mice that merit further study for JNCL biomarker development

The Three Hundred project : A large catalogue of theoretically modelled galaxy clusters for cosmological and astrophysical applications

We introduce the THE THREE HUNDRED project, an endeavour to model 324 large galaxy clusters with full-physics hydrodynamical re-simulations. Here we present the data set and study the differences to observations for fundamental galaxy cluster properties and scaling relations. We find that the modelled galaxy clusters are generally in reasonable agreement with observations with respect to baryonic fractions and gas scaling relations at redshift z = 0. However, there are still some (model-dependent) differences, such as central galaxies being too massive, and galaxy colours (g − r) being bluer (about 0.2 dex lower at the peak position) than in observations. The agreement in gas scaling relations down to 1013h−1M⊙ between the simulations indicates that particulars of the sub-grid modelling of the baryonic physics only has a weak influence on these relations. We also include – where appropriate – a comparison to three semi-analytical galaxy formation models as applied to the same underlying dark-matter-only simulation. All simulations and derived data products are publicly available.Instituto de Astrofísica de La PlataFacultad de Ciencias Astronómicas y Geofísica

DYNLET1 Application to Federal Highway Administration Projects

Source: https://erdc-library.erdc.dren.mil/jspui/This study was sponsored by the U.S. Department of Transportation (DOT) whose primary interest is in the development of a statistical approach for estimating frequency-indexed currents impacting bridge piers at project sites. Model DYNLET1 is used to compute the storm-induced velocities near bridge piers. DYNLETl is a one-dimensional (1-D), shallow-water equation, hydrodynamic model for predicting velocities and water level fluctuations in a system of inlets and bays (Amein and Kraus 1991, 1992). An important feature of the model is the ability to accurately represent flow distribution across any cross section, given the inherent limitations of a 1D model. This report describes the process of applying DYNLETl to a tidal inlet, specifically to Brunswick Harbor, Georgia, for the purpose of estimating tide and storm response at U.S. Department of Transportation (DOT) project sites

Debris Monitoring Observatory Network (DEMON): A high coverage infrastructure for space debris monitoring

The most common methodologies for space debris identification and monitoring involve radar measures, laser ranging and finally optical observations. Although representing the only passive method for debris tracking, optical observations are constrained to reduced time windows, when targets are crossing the penumbra annular region and the observatory is in darkness. On this purpose, an increased amount of optical data can only be assured by a multiplicity of observing stations extending the coverage of the monitoring system. The Sapienza Space Systems and Space Surveillance Laboratory (S5LAB) Research Team at Sapienza - University of Rome has established the Debris Monitoring Observatory Network (DEMON), an international network of optical observatories addressed at debris surveillance. The first six DEMON observatories are owned by S5LAB and located in Rome and surroundings. The two observatories developed by the S5LAB research team in the framework of the Equatorial Observatory (EQUO) project managed by the Italian Space Agency are part of the SSON and located at the Broglio Space Center in Malindi, Kenya, and allow to provide coverage to the equatorial orbital region. Finally, five optical observatories located in Bologna (Italy), Ann Arbor (Michigan, USA), Cerro Tololo (Chile) and Bern (Switzerland) and a radar located in Bonn (Germany) are collaborating with the S5LAB research team as part of the DEMON. Such a spread dislocation of the observing sites allows to increase the accuracy of the obtainable orbital parameters. Moreover, the network observatories distribution allows to increase the European space surveillance capabilities, both allowing to achieve data from sites featuring different meteorological conditions, and to obtain less sparse measurements from longer orbit arcs, facilitating the orbit determination procedure. The whole network has been tested with several observation campaigns, including the Tiangong-1 re-entry campaign performed in support to the Inter-Agency space Debris Committee (IADC). The heterogeneous capabilities of the different observatories represent an advantage for acquiring a wider set of debris monitoring data with different techniques. Indeed, two observing modalities can be applied: a direct tracking can be performed by following the target during its pass over the ground station or the debris track can be recorded while the telescope is performing a sidereal tracking. A strong synergy between our institution and the Italian specialized industry has also revealed to be very productive in the context of the network establishment. The present paper will describe the DEMON infrastructure and the opportunities, improvements and future perspectives for research institutions or space industry of this wide observatories network will be discussed