50 research outputs found

    Challenging conventional views on mobile-telecommunications investment: Evidence from conflict zones

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    What do you need to facilitate investment in mobile telecommunications? Mobile telecommunications has become the silver bullet du jour of international development. And, beyond the hype and alongside some exacerbation of inequities, it can be seen delivering both social and economic development outcomes (Heeks & Jagun 2007). Yet at least half the world's population lack access to this development tool (Kelly 2007). Not surprisingly, then, there is significant interest in understanding those factors which can facilitate greater investment in mobile (and information and communication technologies ā€“ ICTs ā€“ more broadly). Hence, the initial question. To which the standard answer has been that the "investment climate " ā€“ the factors that shape opportunities and incentives for investment (Miglorisi & Galmarini 2004) ā€“ rests on a series of investment "pillars " (Mills & Fan 2006). Those pillars are security and stability, finance and infrastructure, workers and labour markets, and the regulatory framework and tax. Overarching all of these, the view is that good, stable governance forms the crucial basis for investment. In its absence, investment will be curtailed (Hope 2002, EU & UN 2007). This conventional view, emanating from the main international development agencies such as the World Bank, is seen as similar whether considering developing countries generally (World Bank 2005) or those that have been conflict-affected (Mills & Fan 2006). We therefore decided to investigate further, picking out security and good governance as two key elements seen as necessary for facilitating investment, and looking at investment in mobile telecommunications in three countries that had neither during the initial years of the 21st century: Afghanistan, Democratic Republic of Congo, an

    User needs, benefits and integration of robotic systems in a space station laboratory

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    The methodology, results and conclusions of the User Needs, Benefits, and Integration Study (UNBIS) of Robotic Systems in the Space Station Microgravity and Materials Processing Facility are summarized. Study goals include the determination of user requirements for robotics within the Space Station, United States Laboratory. Three experiments were selected to determine user needs and to allow detailed investigation of microgravity requirements. A NASTRAN analysis of Space Station response to robotic disturbances, and acceleration measurement of a standard industrial robot (Intelledex Model 660) resulted in selection of two ranges of low gravity manipulation: Level 1 (10-3 to 10-5 G at greater than 1 Hz.) and Level 2 (less than = 10-6 G at 0.1 Hz). This included an evaluation of microstepping methods for controlling stepper motors and concluded that an industrial robot actuator can perform milli-G motion without modification. Relative merits of end-effectors and manipulators were studied in order to determine their ability to perform a range of tasks related to the three low gravity experiments. An Effectivity Rating was established for evaluating these robotic system capabilities. Preliminary interface requirements were determined such that definition of requirements for an orbital flight demonstration experiment may be established

    The helminth parasite heligmosomoides polygyrus attenuates EAE in an IL-4RĪ±-dependent manner

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    Helminth parasites are effective in biasing Th2 immunity and inducing regulatory pathways that minimize excessive inflammation within their hosts, thus allowing chronic infection to occur whilst also suppressing bystander atopic or autoimmune diseases. Multiple sclerosis (MS) is a severe autoimmune disease characterized by inflammatory lesions within the central nervous system; there are very limited therapeutic options for the progressive forms of the disease and none are curative. Here, we used the experimental autoimmune encephalomyelitis (EAE) model to examine if the intestinal helminth Heligmosomoides polygyrus and its excretory/secretory products (HES) are able to suppress inflammatory disease. Mice infected with H. polygyrus at the time of immunization with the peptide used to induce EAE (myelin-oligodendrocyte glycoprotein, pMOG), showed a delay in the onset and peak severity of EAE disease, however, treatment with HES only showed a marginal delay in disease onset. Mice that received H. polygyrus 4 weeks prior to EAE induction were also not significantly protected. H. polygyrus secretes a known TGF-Ī² mimic (Hp-TGM) and simultaneous H. polygyrus infection with pMOG immunization led to a significant expansion of Tregs; however, administering the recombinant Hp-TGM to EAE mice failed to replicate the EAE protection seen during infection, indicating that this may not be central to the disease protecting mechanism. Mice infected with H. polygyrus also showed a systemic Th2 biasing, and restimulating splenocytes with pMOG showed release of pMOG-specific IL-4 as well as suppression of inflammatory IL-17A. Notably, a Th2-skewed response was found only in mice infected with H. polygyrus at the time of EAE induction and not those with a chronic infection. Furthermore, H. polygyrus failed to protect against disease in IL-4RĪ±āˆ’/āˆ’ mice. Together these results indicate that the EAE disease protective mechanism of H. polygyrus is likely to be predominantly Th2 deviation, and further highlights Th2-biasing as a future therapeutic strategy for MS

    Item-location binding in working memory: Is it hippocampus-dependent?

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    A general consensus is emerging that the hippocampus has an important and active role in the creation of new long-term memory representations of associations or bindings between elements. However, it is less clear whether this contribution can be extended to the creation of temporary bound representations in working memory, involving the retention of small numbers of items over short delays. We examined this by administering a series of recognition and recall tests of working memory for color-location binding and object-location binding to a patient with highly selective hippocampal damage (Jon), and groups of control participants. Jon achieved high levels of accuracy in all working memory tests of recognition and recall binding across retention intervals of up to 10 seconds. In contrast, Jon performed at chance on an unexpected delayed test of the same object-location binding information. These findings indicate a clear dissociation between working memory and long-term memory, with no evidence for a critical hippocampal contribution to item-location binding in working memory

    Epigenetic modification of the PD-1 (Pdcd1) promoter in effector CD4(+) T cells tolerized by peptide immunotherapy

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    Clinically effective antigen-based immunotherapy must silence antigen-experienced effector T cells (Teff) driving ongoing immune pathology. Using CD4+ autoimmune Teff cells, we demonstrate that peptide immunotherapy (PIT) is strictly dependent upon sustained T cell expression of the co-inhibitory molecule PD-1. We found high levels of 5-hydroxymethylcytosine (5hmC) at the PD-1 (Pdcd1) promoter of non-tolerant T cells. 5hmC was lost in response to PIT, with DNA hypomethylation of the promoter. We identified dynamic changes in expression of the genes encoding the Ten-Eleven-Translocation (TET) proteins that are associated with the oxidative conversion 5-methylcytosine and 5hmC, during cytosine demethylation. We describe a model whereby promoter demethylation requires the co-incident expression of permissive histone modifications at the Pdcd1 promoter together with TET availability. This combination was only seen in tolerant Teff cells following PIT, but not in Teff that transiently express PD-1. Epigenetic changes at the Pdcd1 locus therefore determine the tolerizing potential of TCR-ligation. - See more at: http://elifesciences.org/content/3/e03416#sthash.n6isQlkn.dpu
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