A Pure Java Parallel Flow Solver

In this paper an overview is given on the "Have Java" project to attain a pure Java parallel Navier-Stokes flow solver (JParNSS) based on the thread concept and remote method invocation (RMI). The goal of this project is to produce an industrial flow solver running on an arbitrary sequential or parallel architecture, utilizing the Internet, capable of handling the most complex 3D geometries as well as flow physics, and also linking to codes in other areas such as aeroelasticity etc. Since Java is completely object-oriented the code has been written in an object-oriented programming (OOP) style. The code also includes a graphics user interface (GUI) as well as an interactive steering package for the parallel architecture. The Java OOP approach provides profoundly improved software productivity, robustness, and security as well as reusability and maintainability. OOP allows code construction similar to the aerodynamic design process because objects can be software coded and integrated, reflecting actual design procedures. In addition, Java is the programming language of the Internet and thus Java is the programming language of the Internet and thus Java objects on disparate machines or even separate networks can be connected. We explain the motivation for the design of JParNSS along with its capabilities that set it apart from other solvers. In the first two sections we present a discussion of the Java language as the programming tool for aerospace applications. In section three the objectives of the Have Java project are presented. In the next section the layer structures of JParNSS are discussed with emphasis on the parallelization and client-server (RMI) layers. JParNSS, like its predecessor ParNSS (ANSI-C), is based on the multiblock idea, and allows for arbitrarily complex topologies. Grids are accepted in GridPro property settings, grids of any size or block number can be directly read by JParNSS without any further modifications, requiring no additional preparation time for the solver input. In the last section, computational results are presented, with emphasis on multiprocessor Pentium and Sun parallel systems run by the Solaris operating system (OS)

Building personal lives as informal migrants in South Africa : narratives of poor African informal migrants in Johannesburg

This study explores why poor African migrants remain in Johannesburg, South Africa’s harsh migration context, to build their lives, and how, in pursuit of a better future, they engage with the various forms of socioeconomic and political constraints that they experience. Popular as a destination for African migrants, South Africa is a country with a very high percentage of asylum seekers, but also a place where they are the targets of violent xenophobia. Yet such migrants are known to live for years in this situation, one which is generally considered socio-economically and politically marginalized and constraining. Their continued presence raises the pertinent sociological query of how and why such large numbers have remained in their host society, continuing to welcome new incoming members, while others have left, been imprisoned or murdered, or died of a range of ailments. Methodologically, resilience theory - conceptualised as a dynamic process of interaction between the individual and his or her environment – is utilised as an explanatory and descriptive framework to examine the subject of this study. Data for the study were collected through life-story interviews with African migrants who are economically active on the streets of Johannesburg, and document analysis was utilised for triangulation purposes. Data were analysed using narrative analysis. Empirical observations called attention to the prominence of aspirations for a better life amongst the informal migrants, an observation that is accompanied by several relevant findings: firstly, that the migrants’ resilience in their constraining environment cannot be attributed to itemized factors. Rather, their resilience takes the form of a dynamic and interactive engagement with the South African context. The interactions are orchestrated by their perceptions of opportunities in their home countries and the South African society, and combined with the application of faith and tactics in dealing with identified adverse conditions. Their resilience is presented as enduring but also transient, as it is subject to individuals’ evaluations and negotiations. In that light, the migrants are shown to be active agents but also victims in their harsh context, calling attention to the duality of the informal migrants’ experience in Johannesburg, irrespective of their violent xenophobic environment. Consequently, considerable challenges are posed to the projects of classifying informal migrants as either passive victims or active agents, and listing or identifying specific factors as means to attaining resilience. Secondly, an observed fallout from the interviewees’ notion of hope – aspiration – is the productive use of ‘waiting time’. The hegemonic control of the interviewees’ time through, for example, official delays or manipulation in the processing of asylum applications, is challenged by the tactical and creative utilization of the period of waiting in which two things stood out: micro-entrepreneurship and development of their social and personal lives but particularly micro-entrepreneurship, as the interviewees focused on achieving a better life through micro businesses. Their engagement in trade and services in a context devoid of institutional support, and under dire personal circumstances, though borne of feelings of ‘no alternatives’, suggests creativity, with potential for growth. Furthermore, my interviewees were also able to make productive social use of the ‘time of waiting’ even as asylum seekers. Living in the city, my interviewees took initiatives to learn new skills, develop new intimate and business relationships, had children, and so on. Their lives reveal that even as asylum seekers, they were slowly building the futures they desired, for instance, through savings and personal projects in the home country. On the basis of empirical observations, the conclusions drawn indicate the limitations of policy in terms of improving the experience of informal migrants, and raises questions concerning the moral or ethical values (or lack thereof) involved in perpetuating their vulnerability – thus calling attention to questions of choice and agency in acts dehumanising informal migrants. Moreover, observations of micro-entrepreneurship beg another question. Could migration management be mutually beneficial if a context conducive to migrants’ entrepreneurial pursuits is promoted? As a contribution to the body of knowledge of Social Policy, the author uses the perspective of the informal migrants as active agents and social victims to argue that political inclusion by the host country cannot be enough to improve the wellbeing of informal migrants. Thus, the author theoretically reflects on the relevance of Social Policy in improving human welfare and emphasizes the informal migrants’ experience of vulnerability as a creative opportunity to engage the development of Social Policy in Africa, for example, from a regional body. Therefore, the thesis postulates that the dilemma of better lives for informal African migrants is a regional political question of belongingness, care, and social responsibility.Tässä tutkimuksessa tarkastellaan sitä, miksi köyhät afrikkalaiset siirtolaiset jäävät Etelä-Afrikan Johannesburgin ankaraan siirtolaisympäristöön ja miten he elävät erilaisten kohtaamiensa sosioekonomisten ja poliittisten rajoitusten kanssa paremmasta elämästä haaveillen. Etelä-Afrikka on afrikkalaisten siirtolaisten keskuudessa suosittu maa, jossa turvapaikanhakijoita on paljon. Heihin kohdistuu kuitenkin rajua muukalaisvihaa. Silti osa siirtolaisista elää vuosikausia sosioekonomisessa ja poliittisessa marginaalissa rajoituksia sietäen. Heidän jatkuva läsnäolonsa herättää yhteiskunnallisesti tärkeän kysymyksen siitä, miksi niin suuri määrä siirtolaisia on jäänyt isäntäyhteisöön ja miksi uusia tulijoita saapuu jatkuvasti, kun taas toiset ovat lähteneet, joutuneet vankilaan, tulleet murhatuksi tai kuolleet johonkin sairauteen. Aiheen tarkastelussa käytetään resilienssiteoriaa, joka selittää ja kuvaa dynaamista vuorovaikutusprosessia yksilön ja hänen ympäristönsä välillä. Tutkimusmateriaali kerättiin haastattelemalla afrikkalaisia siirtolaisia, jotka ovat taloudellisesti aktiivisia Johannesburgin kaduilla, ja triangulaatiotarkoituksiin käytettiin asiakirja-analyysiä. Tiedot analysoitiin käyttäen narratiivista analyysiä. Empiiristen havaintojen myötä huomio kiinnittyi epävirallisten siirtolaisten toiveisiin paremmasta elämästä. Lisäksi tehtiin useita olennaisia havaintoja – ennen kaikkea se, että siirtolaisten resilienssi rajoittavassa elinympäristössä ei nähtävästi johdu eriteltävistä tekijöistä. Ennemmin heidän resilienssinsä ilmenee dynaamisena ja interaktiivisena osallistumisena eteläafrikkalaisen yhteiskunnan toimintaan. Vuorovaikutus pohjautuu niihin havaintoihin, joita he ovat tehneet omista mahdollisuuksistaan kotimaissaan ja eteläafrikkalaisessa ympäristössä, ja vaikeissa olosuhteissa nojaudutaan uskoon ja taktiikkaan. Heidän sitkeytensä on sekä pysyvää että hetkellistä, sillä se riippuu yksilöiden näkemyksistä ja neuvotteluista. Tässä valossa siirtolaiset näyttäytyvät aktiivisina toimijoina mutta myös vaikean tilanteen uhreina. Huomio kiinnittyy Johannesburgin epävirallisten siirtolaisten kaksinaiseen kokemukseen, joka ei ole riippuvainen väkivaltaisesta ja muukalaisvastaisesta ympäristöstä. Siksi on erittäin haasteellista luokitella epäviralliset siirtolaiset joko passiivisiksi uhreiksi tai aktiivisiksi toimijoiksi ja määrittää tai luetella tiettyjä tekijöitä, jotka edistävät resilienssiä. Toisekseen odotusajan käyttö hyödyllisesti edistää haastateltujen toiveikkuutta ja pyrkimyksiä. Taktinen ja luova odotusajan käyttö kompensoi haastateltujen ajan hegemonista hallintaa esimerkiksi turvapaikanhakuprosessien käsittelyn manipuloinnin tai virallisten viiveiden muodossa. Esiin nousi kaksi seikkaa: mikroyrittäjyys sekä sosiaalisen ja henkilökohtaisen elämän luominen. Ennen kaikkea haastatellut keskittyivät paremman elämän tavoitteluun mikroyrittämisen kautta. Kaupankäynti ja palveluiden tarjoaminen ilman institutionaalista tukea vaikeissa olosuhteissa viittaa luovuuteen ja kasvun mahdollisuuteen, vaikka taustalla olisikin tunne siitä, ettei muita vaihtoehtoja ole. Haastattelemani ihmiset pystyivät turvapaikanhakijoinakin hyödyntämään odotusaikaa myös sosiaalisissa tarkoituksissa. Kaupungissa he opettelivat uusia taitoja, muodostivat uusia henkilökohtaisia ja liiketoiminnallisia suhteita, hankkivat lapsia jne. Turvapaikanhakijan statuksestaan huolimatta he rakensivat toivomaansa tulevaisuutta hiljalleen esimerkiksi säästöjen ja kotimaassaan meneillään olevien henkilökohtaisten hankkeiden avulla. Empiiristen havaintojen perusteella tehdyt johtopäätökset viittaavat siihen, että nykyisissä käytänteissä on parantamisen varaa, jos epävirallisten siirtolaisten kokemusta halutaan parantaa. Ne herättävät kysymyksiä moraalisista ja eettisistä arvoista (tai niiden puutteesta), joita heidän haavoittuvan asemansa salliminen edellyttää. Huomio kiinnittyy epävirallisten siirtolaisten epäinhimillistämiseen liittyvien tekojen ja toimijuuden vapaaehtoisuuteen. Mikroyrittäjyyttä koskevat huomiot herättävät myös kysymyksen siitä, voisiko siirtolaisuuden hallinta olla molemmille osapuolille kannattavaa, jos siirtolaisten yrittäjyyteen liittyviä ponnisteluita tuettaisiin. Kun otetaan huomioon näkemykset epävirallisista siirtolaisista sekä aktiivisina toimijoina että yhteiskunnallisina uhreina, kirjoittaja on sitä mieltä, että isäntämaan poliittinen osallistaminen ei riitä parantamaan epävirallisten siirtolaisten hyvinvointia. Näin ollen kirjoittaja pohtii sosiaalipolitikan merkitystä ihmisten hyvinvoinnin parantamisessa teoreettisella tasolla. Hän haluaa myös nostaa esiin epävirallisten siirtolaisten kokemuksen haavoittuvuudesta luovana mahdollisuutena ja kiinnittää huomiota siihen, että esimerkiksi alueelliset tahot voisivat huomioida tämän seikan Etelä-Afrikan sosiaalipolitiikan kehittämisessä. Tutkielmassa oletetaan näin ollen, että epävirallisten Afrikan-siirtolaisten elämänlaatu on alueellinen poliittinen ongelma, jossa on kyse kuuluvuudesta, välittämisestä ja sosiaalisesta vastuusta

Structuurvisie Vianen Advies over reikwijdte en detailniveau van het milieueffectrapport

Met het vaststellen van de structuurvisie 2030 wil de gemeente Vianen op hoofdlijnen richting geven aan en samenhang brengen in de ruimtelijke ontwikkelingen op het grondgebied die voortkomen uit rijks-, provinciaal en gemeentelijk beleid. Het MER zal inzicht moeten geven in de ontwikkelingen die de structuurvisie maximaal mogelijk maakt, voor zover deze relevant zijn voor het voorspellen van de milieueffecte

The Regulatory Status Adopted by Lymph Node Dendritic Cells and T Cells During Healthy Aging Is Maintained During Cancer and May Contribute to Reduced Responses to Immunotherapy

Aging is associated with an increased incidence of cancer. One contributing factor could be modulation of immune cells responsible for anti-tumor responses, such as dendritic cells (DCs) and T cells. These immunological changes may also impact the efficacy of cancer immunotherapies in the elderly. The effects of healthy aging on DCs and T cells, and their impact on anti-mesothelioma immune responses, had not been reported. This study examined DCs and T cells in young (2-5 months; equivalent to 16-26 human years) and elderly (20-24 months; equivalent to 60-70 human years) healthy and mesothelioma-bearing C57BL/6J mice. During healthy aging, elderly lymph nodes adopted a regulatory profile, characterized by: (i) increased plasmacytoid DCs, (ii) increased expression of the adenosine-producing enzyme CD73 on CD11c+ cells, and (iii) increased expression of multiple regulatory markers (including CD73, the adenosine A2B receptor, CTLA-4, PD-1, ICOS, LAG-3, and IL-10) on CD8+ and CD4+ T cells, compared to lymph nodes from young mice. Although mesotheliomas grew faster in elderly mice, the increased regulatory status observed in healthy elderly lymph node DCs and T cells was not further exacerbated. However, elderly tumor-bearing mice demonstrated reduced MHC-I, MHC-II and CD80 on CD11c+ cells, and decreased IFN-? by CD8+ and CD4+ T cells within tumors, compared to young counterparts, implying loss of function. An agonist CD40 antibody based immunotherapy was less efficient at promoting tumor regression in elderly mice, which may be due to: (i) failure of elderly CD8+ T cells to up-regulate perforin, and (ii) increased expression of multiple regulatory markers on CD11c+ cells and T cells in elderly tumor-draining lymph nodes (including CD73, PD-1, ICOS, LAG-3, and TGF-ß). Our findings suggest that checkpoint blockade may improve responses to immunotherapy in elderly hosts with mesothelioma, and warrants further investigation

DLR-ONERA accurate CFD support for the Pre-X project

During the development of Pre-X demonstrator supported by CNES , industrials are in charge of aerodynamic and aerothermodynamic defintion and characterisation of the vehicle. For this preliminary phase of the project, most of the time industrials only used Euler computations associated to boundary layer, so that a lot of parametric analysis can be carried out and the feasibility of the project was globally checked. It is clear that deeper analyses for some critical trajectory points are required to overcome potential infeasibilities. The main objective of the accurate CFD support, provided by DLR and ONERA consists in assessing these high level objectives. Two critical issues are investigated. The heat fluxes level on the windward side of the body, the deflected flap in the hypersonic regime and the aerodynamic static margin at the end of the trajectory in the supersonic regime. Two relevant codes where used: the TAU code from DLR and CELHYO3D from ONERA. * The unstructured TAU code is a finite volume Navier-Stokes solver which is validated in a wide range of sub- trans- and hypersonic cases. Different one and two equation turbulence models are implemented and chemical equilibrium as well as non equilibrium flows can be modelled. Furthermore adaptation of tetrahedral grids on any given output quantity is possible. * The structured CELHYO3D code is a finite volume Navier-Stokes solver with upwind schemes adapted to supersonic and hypersonic flows. Flows of air or CO2 in chemical or thermo-chemical non-equilibrium can be considered. A specific grid management procedure is used in order to provide shock-adapted grids together with information of the grid-convergence of the results. The results of the computations with TAU and CELHYO3D confirm the feasibility of the project with respect to the heat-flux and static-margin issues

Classing it up to get noticed : MHC class 1 antigen display in dendritic cells and neuroblastoma

In this thesis I have explored the process of MHC-1-mediated antigen presentation in two distinctive cell types: dendritic cells and neuroblastoma tumor cells. Dendritic cells (DCs) are pivotal players that bridge innate and adaptive immunity. DCs are able to engulf tumor-derived material and cross-present tumor-derived antigen fragments to CD8+ T-cells. In Chapter 2, I give an overview of recent literature about cross-presenting tumor cell material by dendritic cells. Tipping the scale towards antigen preservation causes a complete stop of antigenic peptide production and subsequent loss of antigen cross-presentation, as described in Chapter 3. Here, cowpox virus-derived protein CPXV012 delivered into the endosomal pathway of dendritic cells as a soluble protein. In this endosomal environment, soluble CPXV012 colocalizes with endocytosed antigen. By blocking endosomal acidification, it prevents the degradation of antigen, a process that is required to liberate antigenic peptide to be cross-presented by MHC-1. Peptides that are produced by endosomal processing of antigen do not only reach MHC-1 for presentation, but also MHC 2. MHC 2 presents antigen to helper CD4+ T-cells that aid in the priming of CD8+ T-cells. The benefit of reaching both CD4+ and CD8+ T-cells when initiating an immune response is investigated in Chapter 4. Given the pivotal role of dendritic cells in eliciting cellular immunity, they may be useful for therapeutic purposes. In Chapter 5, I explore this option using a vector derived from Rift Valley Fever virus (bunyaviridae) that targets dendritic cells in vitro and in vivo. In prophylactic and therapeutic settings of vaccination this viral vector was able to confer protection against a lymphoma tumor challenge. Neuroblastoma is the most deadly pediatric solid tumor and currently lacks a cellular immunotherapeutic treatment strategy. Tumor-specific CD8+ T-cells may be effective to destroy neuroblastoma tumor cells. However, neuroblastoma tumors were shown not to be immunogenic due to low MHC-1 expression levels and lack of broadly- expressed antigens. How to increase neuroblastoma immunogenicity is discussed in Chapter 6. I show that the preferred antigen in melanoma (PRAME) is expressed in >90% of high-risk neuroblastoma tumors and PRAME-specific T-cells are able to recognize neuroblastoma cells, but only when MHC-1 levels are upregulated e.g. by previous NK cell attack. The regulation of MHC-1 expression in neuroblastoma is further investigated in Chapter 7. MHC-1 expression, and thus T-cell recognition of neuroblastoma, appears to depend on the activation of the transcription factor NFκB. Through systematic gene deletions, I have identified factors that suppress NFκB activity in neuroblastoma cells. Tumor expression of these NFκB supressors are correlated with worse survival of neuroblastoma patients, suggesting they could be relevant targets for the development of future (immuno)therapies against neuroblastoma. Finally, the role of NFκB suppression in neuroblastoma development, immunogenicity and immunotherapy is reviewed and discussed in Chapter 8