3,382 research outputs found
Fictional Hierarchies And Modal Theories Of Fiction
Some philosophers of fiction – most famously Jerold Levinson1 - have tried to argue that fictional narrators can never be identified with real authors. This argument relies on the claim that narration involves genuine assertion (not just the pretense of assertion that lacks truthfulness) and that real authors are not in a position to assert anything about beings on the fictional plain - given that they don’t rationally believe in their existence.
This debate on the status of narrators depends on the idea that fictional beings and beings in the real worlds reside, as it were, at different levels. The assumption that there is a gap separating the levels of fiction and reality serves as a rationale for the claim that real authors could not possibly be en rapport with the fictional characters that they create (e.g. entertain beliefs about them, etc.)
The class group of a minimal model of a quotient singularity
Let be a finite-dimensional vector space over the complex numbers and let
be a finite group. We describe the class group of
a minimal model (that is, -factorial terminalization) of the linear
quotient . We prove that such a class group is completely controlled by
the junior elements contained in
Birational classification of toric orbifolds
We give a complete classification of the torus-equivariant birational
equivalence classes of smooth proper toric Deligne-Mumford stacks with trivial
generic stabilizer in terms of their associated stacky fans.Comment: 7 pages; comments very welcome
A Mechanism-Centred Approach to Evaluating Complex Aid Interventions: The Case of Accompanying Measures to Budget Support
Background: Current methodological debates related to theory-based evaluations (TBE) centre around questions how to improve the explanatory strength of these approaches and how to integrate mechanisms as analytic concept. Particularly in complex aid interventions, when multiple elements are expected to interact and thus create an added value, exploring mechanisms as an analytical tool can be promising.
Purpose: This paper seeks to contribute to the discussion on the use of TBE for evaluating complex aid interventions by sharing experiences from a recent evaluation of accompanying measures to general budget support.
Setting: Nine countries of sub-Saharan Africa which have received German budget support, namely Burkina Faso, Ghana, Malawi, Mali, Mozambique, Rwanda, Tanzania, Uganda, Zambia.
Intervention: Accompanying measures (mainly in the form of technical assistance and capacity development) are one element of the budget support package, which further encompasses financial contributions, policy dialogue, and conditionalities.
Research Design: We focus on interrelations between different elements of budget support and apply a mechanism-centred approach to programme theory building,
Data Collection and Analysis: After defining accompanying measures and integrating them into the intervention logic of budget support used in recent multi-donor evaluations, key mechanisms were identified on an explorative mission to Mozambique, validated in an online survey, and further discussed in expert interviews and during field research in Tanzania.
Findings: For the specific example relating to two elements of budget support (policy dialogue and accompanying measures), some of the hypothesized mechanisms were found to create an added value and thus increase the effectiveness of budget support as a package. The applied approach helped generate a more comprehensive implementation theory and provided insights into potential benefits and challenges of combining different elements in one programme. Beyond its use for future evaluations in the field of budget support, we argue that TBE of complex interventions can benefit from adopting such a mechanism-centred approach to create a better understanding of how different elements of the programme interact. Moreover, the focus on mechanisms when analysing programme implementation enables evaluators to improve their empirical inquiry on the identified mechanisms and to draw valid conclusions on the programme’s contribution to the observed outcomes.
Keywords: Theory-based evaluation; theory of change; development evaluation; budget support; technical assistance; capacity development
Chow rings of stacks of prestable curves I
We study the Chow ring of the moduli stack of prestable
curves and define the notion of tautological classes on this stack. We extend
formulas for intersection products and functoriality of tautological classes
under natural morphisms from the case of the tautological ring of the moduli
space of stable curves. This paper provides
foundations for the second part of the paper.
In the appendix (joint with J. Skowera), we develop the theory of a proper,
but not necessary projective, pushforward of algebraic cycles. The proper
pushforward is necessary for the construction of the tautological rings of
and is important in its own right. We also develop
operational Chow groups for algebraic stacks.Comment: This paper is the first part of the previous version which has been
split off due to length. An appendix (joint with Jonathan Skowera) about
proper pushforwards for Chow groups of Artin stacks has been added. 65 pages.
Comments are very welcome
Induction of reactive oxygen species and cell survival in the presence of advanced glycation end products and similar structures
AbstractAdvanced glycation end products (AGEs) that arise from the reaction of sugars with protein side chains and the terminal amino group are supposed to be involved in the pathogenesis of several diseases and therefore the effects of AGEs on cells are the objective of numerous investigations. The effects of AGEs on cells are commonly assumed to be transduced via the receptor for AGEs (RAGE) but there are also other receptors known to interact with AGEs and they are likely to be involved in signal transduction. The primary cellular effect of AGEs on cultured cells was found to be the formation of reactive oxygen species (ROS). For the present study one murine and three human cell lines were used. The effects of a set of different highly modified AGEs and AGE-like compounds derived from the incubation of different modifiers with BSA were tested for their effects on these cells. Almost all AGEs tested induced the production of reactive oxygen species (ROS) in the different cell lines although the intensity of the detected signals varied considerably between the cell lines and are strongly dependent on the AGE used for cell activation. The most highly modified BSA-species were shown to inhibit cell growth in all cell lines, whereas a moderately modified glucose derived BSA-AGE and BSA-GAred did not show any inhibitory effect on cell growth even when a high ROS formation was detected
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