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Leveraging private investment to expand renewable power generation: Evidence on financial additionality and productivity gains from Uganda
Effectively mitigating climate change entails a quick upscaling and redirection of electricity infrastructure investment. Given that the bulk of greenhouse gas emissions increases until 2050 will come from low- and middle-income countries, finding cost-effective ways to mitigate climate change while meeting development targets is essential. However, recent research has shown some of the limitations of broad financing mechanisms, such as the Clean Development Mechanism (CDM) and existing carbon markets. This has resulted in a growing interest in designing novel investment support schemes, such as modifications of targeted feed-in-tariffs (FiTs) that may be more cost effective and better targeted towards particular outcomes when compared to traditional deployment subsidies or broad financing mechanisms. We evaluate the design and outcomes of one such novel support schemes: the GET FiT (Global Energy Transfer Feed-in Tariff) investment support scheme in Uganda, which has attracted ~ 453 million USD in private sector investment for 17 small-scale renewable energy projects (solar, hydro, bagasse) in only three years. Using financial modelling on detailed project-level data, we find that the majority of projects were additional and would therefore not have been built without the subsidy. In addition, using firm-level panel data, we show that power outages hamper manufacturing performance in Uganda. In the absence of reliable outage-data for the entire Ugandan territory, we use nightlight variations to proxy changes in outages. We show that outages have declined substantially since the introduction of GET FiT. Yet, our analysis also demonstrates that programmes to incentivise additional renewable generation in developing countries funded internationally or domestically should liaise closely with grid authorities to ensure that supply does not outstrip demand.European Union’s Horizon 2020 INNOPATHS project (Grant agreement no. 730403)
The Department of Land Economy and the School of Humanities and Social Sciences, University of Cambridge
Heinrich Böll Foundation
Rubber friction: role of the flash temperature
When a rubber block is sliding on a hard rough substrate, the substrate
asperities will exert time-dependent deformations of the rubber surface
resulting in viscoelastic energy dissipation in the rubber, which gives a
contribution to the sliding friction. Most surfaces of solids have roughness on
many different length scales, and when calculating the friction force it is
necessary to include the viscoelastic deformations on all length scales. The
energy dissipation will result in local heating of the rubber. Since the
viscoelastic properties of rubber-like materials are extremely strongly
temperature dependent, it is necessary to include the local temperature
increase in the analysis. At very low sliding velocity the temperature increase
is negligible because of heat diffusion, but already for velocities of order
0.01 m/s the local heating may be very important. Here I study the influence of
the local heating on the rubber friction, and I show that in a typical case the
temperature increase results in a decrease in rubber friction with increasing
sliding velocity for v > 0.01 m/s. This may result in stick-slip instabilities,
and is of crucial importance in many practical applications, e.g., for the
tire-road friction, and in particular for ABS-breaking systems.Comment: 22 pages, 27 figure
Bildung einer Fiskalunion: Ein wirkungsvolles Instrument zur Stabilisierung der Eurozone?
Im Juni 2015 legten Jean-Claude Juncker, Donald Tusk, Jeroen Dijsselbloem, Mario Draghi und Martin Schulz Vorschläge zur »langfristigen Stärkung der Währungsunion« vor. Sie sehen unter anderem auch die Einsetzung eines beratenden Europäischen Fiskalausschusses vor, der die Arbeit der nationalen Räte für Finanzpolitik koordinieren soll. Kann das ein wirkungsvolles Instrument zur Stabilisierung der Eurozone sein? Nach Ansicht von Charles B. Blankart, Humboldt-Universität zu Berlin und Universität Luzern, hat sich die Europäische Union seit etwa 1992 grundlegend verändert. Während sie bis dahin dem zweiseitigen Handel, einem privaten Gut diente, stehe seither der Euro als ein öffentliches Gut im Vordergrund. Blankart sieht in den Zielen der Vorschläge die bekannten »Öffentlichen-Gut-Probleme« des Euro. Die Vorleistungen des einen bewirken nicht automatisch Gegenleistungen des anderen. Das Freifahrerverhalten wird nicht beseitigt. Katharina Gnath, Bertelsmann Stiftung, und Jörg Haas, Jacques Delors Institut – Berlin, argumentieren, dass eine Fiskalunion nur dann stabilisieren kann, wenn sie sowohl glaubwürdige Haushaltsregeln als auch Elemente der Teilung von Risiko umfasst. Sie sei ein wichtiges Mittel zur wirksamen Stärkung der Eurozone, dürfe aber nicht das einzige bleiben. Thiess Büttner, Universität Erlangen-Nürnberg, ist der Ansicht, dass der Vorschlag kaum geeignet sei, die Europäische Währungsunion durchgreifend zu stabilisieren. Je nach der Ausgestaltung könnte er sich sogar als kontraproduktiv erweisen. Frank Westermann, Universität Osnabrück, sieht Parallelen in der jüngsten Entwicklung der Europäischen Währungsunion zu derjenigen Ostdeutschlands nach der Wiedervereinigung. Die reale Lohnentwicklung eile der Produktivität voraus, und es entwickle sich ein Transfersystem, das einen Aufschub notwendiger Arbeitsmarktreformen ermögliche. Eine langfristig expansive Fiskalpolitik, die in einer Fiskalunion insÂtitutionalisiert würde, könne nur kurzfristig die Nachf
DC generation from peripheral blood mononuclear cells in patients with chronic myeloid leukemia: Influence of interferons on DC yield and functional properties
In Chronic Myeloid Leukemia (CML), standard treatment consists of modern tyrosine-kinase inhibitors (TKI). Nevertheless, there is evidence that immune responses against leukemia-associated antigens (LAA) may play an important role in disease control. Dendritic cell (DC)- based immunotherapy is able to induce T cell responses against LAA and might therefore pose an interesting therapeutic option in CML, especially in the setting of minimal residual disease (MRD). GMP production of DC for clinical vaccination remains a time- and cost- intensive procedure and standardized DC generation is warranted. We asked whether maturation-induction with IFN-{gamma} and IFN-{alpha} has an influence on functional properties of DC derived from peripheral blood mononuclear cells (PBMC) in CML patients. Monocyte-derived DC from healthy donors and from patients with CML were analyzed after maturation-induction with our TNF-{alpha}-containing standard cytokine cocktail with or without addition of IFN-{alpha} and/or IFN-{gamma}. Our results confirm that the addition of IFN-{gamma} leads to enhanced IL-12 secretion in healthy donors. In contrast, in CML patients, IFN-{gamma} was not able to increase IL-12 secretion, possibly due to a higher degree of cell adherence and lower cell yield during the cell culture. Our data suggest, that- in contrast to healthy donors-, additional interferons are not beneficial for maturation induction during large-scale DC production in patients with CML
Immunological Memory Transferred with CD4 T Cells Specific for Tuberculosis Antigens Ag85B-TB10.4: Persisting Antigen Enhances Protection
BACKGROUND:High levels of death and morbidity worldwide caused by tuberculosis has stimulated efforts to develop a new vaccine to replace BCG. A number of Mycobacterium tuberculosis (Mtb)-specific antigens have been synthesised as recombinant subunit vaccines for clinical evaluation. Recently a fusion protein of TB antigen Ag85B combined with a second immunodominant TB antigen TB10.4 was emulsified with a novel non-phospholipid-based liposomal adjuvant to produce a new subunit vaccine, investigated here. Currently, there is no consensus as to whether or not long-term T cell memory depends on a source of persisting antigen. To explore this and questions regarding lifespan, phenotype and cytokine patterns of CD4 memory T cells, we developed an animal model in which vaccine-induced CD4 memory T cells could transfer immunity to irradiated recipients. METHODOLOGY/PRINCIPAL FINDINGS:The transfer of protective immunity using Ag85B-TB10.4-specific, CD45RB(low) CD62L(low) CD4 T cells was assessed in sub-lethally irradiated recipients following challenge with live BCG, used here as a surrogate for virulent Mtb. Donor T cells also carried an allotype marker allowing us to monitor numbers of antigen-specific, cytokine-producing CD4 T cells in recipients. The results showed that both Ag85B-TB10.4 and BCG vaccination induced immunity that could be transferred with a single injection of 3x10(6) CD4 T cells. Ten times fewer numbers of CD4 T cells (0.3x10(6)) from donors immunised with Ag85B-TB10.4 vaccine alone, transferred equivalent protection. CD4 T cells from donors primed by BCG and boosted with the vaccine similarly transferred protective immunity. When BCG challenge was delayed for 1 or 2 months after transfer (a test of memory T cell survival) recipients remained protected. Importantly, recipients that contained persisting antigen, either live BCG or inert vaccine, showed significantly higher levels of protection (p<0.01). Overall the numbers of IFN-gamma-producing CD4 T cells were poorly correlated with levels of protection. CONCLUSIONS/SIGNIFICANCE:The Ag85B-TB10.4 vaccine, with or without BCG-priming, generated TB-specific CD4 T cells that transferred protective immunity in mice challenged with BCG. The level of protection was enhanced in recipients containing a residual source of specific antigen that could be either viable or inert
Investigating the association between children’s screen media exposure and vocabulary size in the UK
Children are growing up in a digital age with increasing exposure to television and touchscreen devices. We tested whether exposure to screen media is associated with children’s early language development. One hundred and thirty-one highly educated caregivers of UK children aged 6–36 months completed a media exposure questionnaire and vocabulary measure. 99% of children were read to daily, 82% watched television, and 49% used mobile touchscreen devices daily. Regression analyses revealed that time spent reading positively predicted vocabulary comprehension and production scores at 6–18 months, but time spent engaging with television or mobile touchscreen devices was not associated with vocabulary scores. Critically, correlations revealed that time spent reading or engaging with other non-screen activities was not offset by time spent engaging with television or mobile touchscreen devices. Thus, there was no evidence to suggest that screen media exposure adversely influenced vocabulary size in our sample of highly educated families with moderate media use
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