Desegregation and Black Achievement: A Review of the Research

Holmen Paper is one of Sweden’s leading manufacturer of paper, with two Swedish production facilities located in Norrköping and Hallstavik. The European continent constitutes the company’s largest customer base which makes the company’s distribution system an integral part of the business. Historically, much of the produced paper has been transported by vessels, as vessels allow large volumes of goods and deliveries to markets which are difficult to reach with other modes of transportation. On the first of January 2015, a new EU directive enters into force which regulates the allowed fuels for vessel transports. This directive leads to an increase in cost for vessel transports due to more expensive fuels needing to be used to comply with the new rules. Therefore, Holmen Paper is interested in evaluating alternatives to the distribution system used today, focusing on the product flow between the Swedish production facilities. Thereof, the purpose of this study is to evaluate four predetermined scenarios regarding the distribution system from a capacity and cost perspective. The first scenario is based on the same distribution system Holmen Paper is using today, which does not include a product flow between the Swedish production facilities. The other three scenarios, in contrast to the first, do include a production flow between Hallstavik and Norrköping. For these scenarios a particular volume of the produced paper in Hallstavik will firstly be transported to Norrköping, then be placed in the warehouse of finished goods and lastly be loaded on new modes of transportation. For the second scenario, the production flow between Hallstavik and Norrköping is based on a combination between rail and road transports. The third scenario is based on only road transports and the last scenario is based on vessel transports between Hallstavik and Norrköping. To perform an evaluation of each scenario, the authors designed a study-specific course of action whose structure is based on four different steps. The first step was a mapping of the operations at the facilities’ warehouses for finished products. The second step was to use the mapping results to calculate the available capacity in the warehouses. The third step was an estimation of the capacity demand which would arise in each scenario, depending on the design of the product flow. The last step of the course of action is to calculate the cost for providing the necessary capacities which was calculated in the previous step. The costs were based on three theoretically chosen logistic costs, called warehousing cost, inventory cost and transportation cost. After a total of 16 days of time measuring at the production facilities, the authors were able to combine the measurement results with the 2015 projected production volumes and for each scenario calculate a capacity need along with the associated costs. The first scenario meant a capacity need below the available capacity and the lowest yearly cost in a comparison with the other scenarios. The calculations for the second scenario also resulted in a capacity need below the available capacity along with the highest yearly cost. The third scenario’s capacity need exceeded the available capacity. This was regarding loading docks and forklift trucks for lorry loading in Hallstavik, as well as personnel in Norrköping. The costs needed to manage this scenario, which meant an increase in personnel in Norrköping, reached the second highest yearly cost. The calculated capacity need for the fourth scenario was below the current available capacity. The cost for this scenario was calculated as the second lowest. To validate the result, the authors performed sensitivity analyzes where the effects of some of the assumptions and simplifications which has been made to produce the result were tested. The sensitivity analyzes showed that some of the assumptions affected the end result but the authors still deem that the relationship regarding capacity need between the scenarios show a representative image of reality

Dynamical Effects of Ionospheric Conductivity on the Formation of Polar Cap Arcs

By using a magnetosphere-ionosphere (M-I) coupling model of polar cap arcs [Zhu et al., 1993], a systematic model study of the effects of ionospheric background conductivity on the formation of polar cap arcs has been conducted. The variations of the ionospheric background conductivity in the model study cover typical ionospheric conditions, including solar minimum, solar maximum, winter, and summer. The simulation results clearly indicate that the ionospheric background conductivity can dynamically affect the mesoscale features of polar cap arcs through a nonlinear M-I coupling process associated with the arcs

An EAGLE’s View of Ex-situ Galaxy Growth

Modern observational and analytic techniques now enable the direct measurement of star formation histories and the inference of galaxy assembly histories. However, current theoretical predictions of assembly are not ideally suited for direct comparison with such observational data. We therefore extend the work of prior examinations of the contribution of ex-situ stars to the stellar mass budget of simulated galaxies. Our predictions are specifically tailored for direct testing with a new generation of observational techniques by calculating ex-situ fractions as functions of galaxy mass and morphological type, for a range of surface brightnesses. These enable comparison with results from large FoV IFU spectrographs, and increasingly accurate spectral fitting, providing a look-up method for the estimated accreted fraction. We furthermore provide predictions of ex-situ mass fractions as functions of galaxy mass, galactocentric radius and environment. Using z = 0 snapshots from the 100cMpc3 and 25cMpc3 EAGLE simulations we corroborate the findings of prior studies, finding that ex-situ fraction increases with stellar mass for central and satellite galaxies in a stellar mass range of 2× 107 - 1.9× 1012 M⊙. For those galaxies of mass M*>5× 108M⊙, we find that the total ex-situ mass fraction is greater for more extended galaxies at fixed mass. When categorising satellite galaxies by their parent group/cluster halo mass we find that the ex-situ fraction decreases with increasing parent halo mass at fixed galaxy mass. This apparently counter-intuitive result may be due to high passing velocities within large cluster halos inhibiting efficient accretion onto individual galaxies

Constraining the shape of dark matter haloes with globular clusters and diffuse stellar light in the E-MOSAICS simulations

We explore how diffuse stellar light and globular clusters (GCs) can be used to trace the matter distribution of their host halo using an observational methodology. For this, we use 117 simulated dark matter (DM) haloes from the periodic volume of the E-MOSAICS project. For each halo, we compare the stellar surface brightness and GC projected number density maps to the surface density of DM. We find that the dominant structures identified in the stellar light and GCs correspond closely with those from the DM. Our method is unaffected by the presence of satellites and its precision improves with fainter GC samples. We recover tight relations between the dimensionless profiles of stellar-to-DM surface density and GC-to-DM surface density, suggesting that the profile of DM can be accurately recovered from the stars and GCs (σ ≤ 0.5 dex). We quantify the projected morphology of DM, stars, and GCs and find that the stars and GCs are more flattened than the DM. Additionally, the semimajor axes of the distribution of stars and GCs are typically misaligned by ∼10 degrees from that of DM. We demonstrate that deep imaging of diffuse stellar light and GCs can place constraints on the shape, profile, and orientation of their host halo. These results extend down to haloes with central galaxies M⋆ ≥ 1010 M⊙, and the analysis will be applicable to future data from the Euclid, Roman, and the Rubin observatorie

In Vitro Generation of Interleukin 10–producing Regulatory CD4+ T Cells Is Induced by Immunosuppressive Drugs and Inhibited by T Helper Type 1 (Th1)– and Th2-inducing Cytokines

We show that a combination of the immunosuppressive drugs, vitamin D3 and Dexamethasone, induced human and mouse naive CD4+ T cells to differentiate in vitro into regulatory T cells. In contrast to the previously described in vitro derived CD4+ T cells, these cells produced only interleukin (IL)-10, but no IL-5 and interferon (IFN)-γ, and furthermore retained strong proliferative capacity. The development of these IL-10–producing cells was enhanced by neutralization of the T helper type 1 (Th1)- and Th2–inducing cytokines IL-4, IL-12, and IFN-γ. These immunosuppressive drugs also induced the development of IL-10–producing T cells in the absence of antigen-presenting cells, with IL-10 acting as a positive autocrine factor for these T cells. Furthermore, nuclear factor (NF)-κB and activator protein (AP)-1 activities were inhibited in the IL-10–producing cells described here as well as key transcription factors involved in Th1 and Th2 subset differentiation. The regulatory function of these in vitro generated IL-10–producing T cells was demonstrated by their ability to prevent central nervous system inflammation, when targeted to the site of inflammation, and this function was shown to be IL-10 dependent. Generating homogeneous populations of IL-10–producing T cells in vitro will thus facilitate the use of regulatory T cells in immunotherapy

A comparison of observed and simulated absorption from H i, C iv, and Si iv around z ≈ 2 star-forming galaxies suggests redshift–space distortions are due to inflows

We study H I and metal-line absorption around z ≈ 2 star-forming galaxies by comparing an analysis of data from the Keck Baryonic Structure Survey to mock spectra generated from the Evolution and Assembly of Galaxies and their Environments (EAGLE) cosmological, hydrodynamical simulations. We extract sightlines from the simulations and compare the properties of the absorption by H I, C IV, and Si IV around simulated and observed galaxies using pixel optical depths. We mimic the resolution, pixel size, and signal-to-noise ratio of the observations, as well as the distributions of impact parameters and galaxy redshift errors. We find that the EAGLE reference model is in excellent agreement with the observations. In particular, the simulation reproduces the high metal-line optical depths found at small galactocentric distances, the optical depth enhancements out to impact parameters of 2 proper Mpc, and the prominent redshift–space distortions which we find are due to peculiar velocities rather than redshift errors. The agreement is best for halo masses ∼1012.0 M⊙, for which the observed and simulated stellar masses also agree most closely. We examine the median ion mass-weighted radial gas velocities around the galaxies, and find that most of the gas is infalling, with the infall velocity depending on halo rather than stellar mass. From this, we conclude that the observed redshift–space distortions are predominantly caused by infall rather than outflows

Phase-ordering dynamics of the Gay-Berne nematic liquid crystal

Phase-ordering dynamics in nematic liquid crystals has been the subject of much active investigation in recent years in theory, experiments and simulations. With a rapid quench from the isotropic to nematic phase a large number of topological defects are formed and dominate the subsequent equilibration process. We present here the results of a molecular dynamics simulation of the Gay-Berne model of liquid crystals after such a quench in a system with 65536 molecules. Twist disclination lines as well as type-1 lines and monopoles were observed. Evidence of dynamical scaling was found in the behavior of the spatial correlation function and the density of disclination lines. However, the behavior of the structure factor provides a more sensitive measure of scaling, and we observed a crossover from a defect dominated regime at small values of the wavevector to a thermal fluctuation dominated regime at large wavevector.Comment: 18 pages, 16 figures, animations available at http://www.physics.brown.edu/Users/faculty/pelcovits/lc/coarsening.htm