390 research outputs found
Zeroth Poisson homology of symmetric powers of isolated quasihomogeneous surface singularities
Let X be a surface with an isolated singularity at the origin, given by the
equation Q(x,y,z)=0, where Q is a weighted-homogeneous polynomial. In
particular, this includes the Kleinian surfaces X = C^2/G for G < SL(2,C)
finite. Let Y be the n-th symmetric power of X. We compute the zeroth Poisson
homology of Y, as a graded vector space with respect to the weight grading. In
the Kleinian case, this confirms a conjecture of Alev, that the zeroth Poisson
homology of the n-th symmetric power of C^2/G is isomorphic to the zeroth
Hochschild homology of the n-th symmetric power of the algebra of G-invariant
differential operators on C. That is, the Brylinski spectral sequence
degenerates in this case. In the elliptic case, this yields the zeroth
Hochschild homology of symmetric powers of the elliptic algebras with three
generators modulo their center, for the parameter equal to all but countably
many points of the elliptic curve.Comment: 17 page
What can we learn from service model analysis? An application in the government export finance sector
The service model approach, like business models in the private sector, is gaining increasing attention in public management literature. In line with this evolving discourse, our study analyzes service models in government export promotion. By exploring the use of service models and discussing key developments, we shed light on the diverse application of service models in the context of officially supported export credits – an under-researched field in which a lot of innovation is happening. We observe a limited number of traditional service models with significant relevance. In addition, our findings suggest a rising diversity that signifies innovation and the broadening scope of activities. We also uncover the underlying motivations and practical experiences associated with their implementation and provide valuable insights into the benefits they offer.The author(s) received no financial support for the research, authorship, and/or publication of this article
Liposomal amphotericin B twice weekly as antifungal prophylaxis in paediatric haematological malignancy patients
AbstractData on antifungal prophylaxis in paediatric cancer patients at high risk for invasive fungal disease (IFD) are scant. Intermittent administration of liposomal amphotericin B (LAMB) has been shown to be safe and effective in adult patients with haematological malignancies. We prospectively evaluated the safety and efficacy of prophylactic LAMB at a dosage of 2.5 mg/kg twice weekly in children at high risk for IFD. Efficacy was compared with that in a historical control group of patients with similar demographic characteristics not receiving LAMB prophylaxis. A total of 46 high-risk patients (24 boys; mean age, 7.7 years) with 187 episodes of antifungal prophylaxis were analysed. The median duration of neutropenia (<500/µL) was 10 days. LAMB was discontinued in four patients because of acute allergic reactions. Median values for creatinine and liver enzymes at end of treatment did not differ significantly from those at baseline. Hypokalaemia (<3.0 mmol/L) occurred with 13.5% of the prophylactic episodes, but was usually mild and always reversible. No proven/probable IFD occurred in patients receiving LAMB prophylaxis. In comparison, five proven and two probable IFDs were observed in 45 historical controls not receiving LAMB prophylaxis (p 0.01). LAMB prophylaxis had no impact on the use of empirical antifungal therapy. Systemic antifungal prophylaxis with LAMB 2.5 mg/kg twice weekly is feasible and safe, and seems to be an effective approach for antifungal prophylaxis in high-risk paediatric cancer patients
Magnetism and superconductivity driven by identical 4 states in a heavy-fermion metal
The apparently inimical relationship between magnetism and superconductivity
has come under increasing scrutiny in a wide range of material classes, where
the free energy landscape conspires to bring them in close proximity to each
other. This is particularly the case when these phases microscopically
interpenetrate, though the manner in which this can be accomplished remains to
be fully comprehended. Here, we present combined measurements of elastic
neutron scattering, magnetotransport, and heat capacity on a prototypical heavy
fermion system, in which antiferromagnetism and superconductivity are observed.
Monitoring the response of these states to the presence of the other, as well
as to external thermal and magnetic perturbations, points to the possibility
that they emerge from different parts of the Fermi surface. This enables a
single 4 state to be both localized and itinerant, thus accounting for the
coexistence of magnetism and superconductivity.Comment: 4 pages, 4 figure
Classes on compactifications of the moduli space of curves through solutions to the quantum master equation
In this paper we describe a construction which produces classes in a
compactification of the moduli space of curves. This construction extends a
construction of Kontsevich which produces classes in the open moduli space from
the initial data of a cyclic A-infinity algebra. The initial data for our
construction is what we call a `quantum A-infinity algebra', which arises as a
type of deformation of a cyclic A-infinity algebra. The deformation theory for
these structures is described explicitly. We construct a family of examples of
quantum A-infinity algebras which extend a family of cyclic A-infinity
algebras, introduced by Kontsevich, which are known to produce all the
Miller-Morita-Mumford classes using his construction.Comment: This version includes an updated list of reference
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