13,868 research outputs found
Care, Social Practices and Normativity. Inner Struggle versus Panglossian Rule-Following
Contrary to the popular assumption that linguistically mediated social practices constitute the normativity of action (Kiverstein and Rietveld, 2015; Rietveld, 2008a,b; Rietveld and Kiverstein, 2014), I argue that it is affective care for oneself and others that primarily constitutes this kind of normativity. I argue for my claim in two steps. First, using the method of cases I demonstrate that care accounts for the normativity of action, whereas social practices do not. Second, I show that a social practice account of the normativity of action has unwillingly authoritarian consequences in the sense that humans act only normatively if they follow social rules. I suggest that these authoritarian consequences are the result of an uncritical phenomenology of action and the fuzzy use of ānormativeā. Accounting for the normativity of action with care entails a realistic picture of the struggle between what one cares for and often repressive social rules
Projective modules over non-commutative tori: classification of modules with constant curvature connection
We study finitely generated projective modules over noncommutative tori. We
prove that for every module with constant curvature connection the
corresponding element of the K-group is a generalized quadratic exponent
and, conversely, for every positive generalized quadratic exponent in the
K-group one can find such a module with constant curvature connection that
. In physical words we give necessary and sufficient conditions for
existence of 1/2 BPS states in terms of topological numbers.Comment: Latex. Misprints correcte
On an Effective Solution of the Optimal Stopping Problem for Random Walks
We find a solution of the optimal stopping problem for the case when a reward function is an integer function of a random walk on an infinite time interval. It is shown that an optimal stopping time is a first crossing time through a level defined as the largest root of Appell's polynomial associated with the maximum of the random walk. It is also shown that a value function of the optimal stopping problem on the finite interval {0, 1, ? , T} converges with an exponential rate as T approaches infinity to the limit under the assumption that jumps of the random walk are exponentially bounded.optimal stopping; random walk; rate of convergence; Appell polynomials
On a Solution of the Optimal Stopping Problem for Processes with Independent Increments
We discuss a solution of the optimal stopping problem for the case when a reward function is a power function of a process with independent stationary increments (random walks or Levy processes) on an infinite time interval. It is shown that an optimal stopping time is the first crossing time through a level defined as the largest root of the Appell function associated with the maximum of the underlying process.
DART-ID increases single-cell proteome coverage.
Analysis by liquid chromatography and tandem mass spectrometry (LC-MS/MS) can identify and quantify thousands of proteins in microgram-level samples, such as those comprised of thousands of cells. This process, however, remains challenging for smaller samples, such as the proteomes of single mammalian cells, because reduced protein levels reduce the number of confidently sequenced peptides. To alleviate this reduction, we developed Data-driven Alignment of Retention Times for IDentification (DART-ID). DART-ID implements principled Bayesian frameworks for global retention time (RT) alignment and for incorporating RT estimates towards improved confidence estimates of peptide-spectrum-matches. When applied to bulk or to single-cell samples, DART-ID increased the number of data points by 30-50% at 1% FDR, and thus decreased missing data. Benchmarks indicate excellent quantification of peptides upgraded by DART-ID and support their utility for quantitative analysis, such as identifying cell types and cell-type specific proteins. The additional datapoints provided by DART-ID boost the statistical power and double the number of proteins identified as differentially abundant in monocytes and T-cells. DART-ID can be applied to diverse experimental designs and is freely available at http://dart-id.slavovlab.net
Microphase separation in thin block copolymer films: a weak segregation mean-field approach
In this paper we consider thin films of AB block copolymer melts confined
between two parallel plates. The plates are identical and may have a preference
for one of the monomer types over the other. The system is characterized by
four parameters: the Flory-Huggins chi-parameter, the fraction f of A-monomers
in the block copolymer molecules, the film thickness d, and a parameter h
quantifying the preference of the plates for the monomers of type A. In certain
regions of parameter space, the film will be microphase separated. Various
structures have been observed experimentally, each of them characterized by a
certain symmetry, orientation, and periodicity. We study the system
theoretically using the weak segregation approximation to mean field theory. We
restrict our analysis to the region of the parameter space where the film
thickness d is close to a small multiple of the natural periodicity. We will
present our results in the form of phase diagrams in which the absolute value
of the deviation of the film thickness from a multiple of the bulk periodicity
is placed along the horizontal axis, and the chi-parameter is placed along the
vertical axis; both axes are rescaled with a factor which depends on the
A-monomer fraction f. We present a series of such phase diagrams for increasing
values of the surface affinity for the A-monomers. We find that if the film
thickness is almost commensurate with the bulk periodicity, parallel
orientations of the structures are favoured over perpendicular orientations. We
also predict that on increasing the surface affinity, the region of stability
of the bcc phase shrinks.Comment: 35 pages, 20 figure
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