108 research outputs found
invariant convex sets in polar representations
We study a compact invariant convex set E in a polar representation of a compact Lie group. Polar rapresentations are given by the adjoint action of K on p, where K is a maximal compact subgroup of a real semisimple Lie group G with Lie algebra g=k⊕p. If a⊂p is a maximal abelian subalgebra, then P=E∩a is a convex set in a. We prove that up to conjugacy the face structure of E is completely determined by that of P and that a face of E is exposed if and only if the corresponding face of P is exposed. We apply these results to the convex hull of the image of a restricted momentum map
Chemoradiotherapy (Gemox plus helical tomotherapy) for unresectable locally advanced pancreatic cancer: A phase II study
The aim of the study was to evaluate the safety and efficacy of a new chemo-radiotherapy regimen for patients with locally advanced pancreatic cancer (LAPC). Patients were treated as follows: gemcitabine 1000 mg/m2 on day 1, and oxaliplatin 100 mg/m2 on day 2, every two weeks (GEMOX regimen) for 4 cycles, 15 days off, hypofractionated radiotherapy (35 Gy in 7 fractions in 9 consecutive days), 15 days off, 4 additional cycles of GEMOX, restaging. From April 2011 to August 2016, a total of 42 patients with non resectable LAPC were enrolled. Median age was 67 years (range 41\u201375). Radiotherapy was well tolerated and the most frequently encountered adverse events were mild to moderate nausea and vomiting, abdominal pain and fatigue. In total, 9 patients underwent surgical laparotomy (5 radical pancreatic resection 1 thermoablation and 3 explorative laparotomy), 1 patient became operable but refused surgery. The overall resectability rate was 25%, while the R0 resection rate was 12.5%. At a median follow-up of 50 months, the median progression-free survival and overall survival were 9.3 (95% CI 6.2\u201314.9) and 15.8 (95% CI 8.2\u201323.4) months, respectively. The results demonstrate the feasibility of a new chemo-radiotherapy regimen as a potential treatment for unresectable LAPC
Some discretizations of geometric evolution equations and the Ricci iteration on the space of Kahler metrics, I
In this article and in its sequel we propose the study of certain
discretizations of geometric evolution equations as an approach to the study of
the existence problem of some elliptic partial differential equations of a
geometric nature as well as a means to obtain interesting dynamics on certain
infinite-dimensional spaces. We illustrate the fruitfulness of this approach in
the context of the Ricci flow, as well as another flow, in Kahler geometry. We
introduce and study dynamical systems related to the Ricci operator on the
space of Kahler metrics that arise as discretizations of these flows. We pose
some problems regarding their dynamics. We point out a number of applications
to well-studied objects in Kahler and conformal geometry such as constant
scalar curvature metrics, Kahler-Ricci solitons, Nadel-type multiplier ideal
sheaves, balanced metrics, the Moser-Trudinger-Onofri inequality, energy
functionals and the geometry and structure of the space of Kahler metrics.
E.g., we obtain a new sharp inequality strengthening the classical
Moser-Trudinger-Onofri inequality on the two-sphere
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Feminist Solidarities: Theoretical and Practical Complexities
This article considers the resurgence of interest in feminist solidarity in theory and practice in the contemporary moment in the United States and UK. What does feminist solidarity mean, what forms is it taking, and how might it proliferate? We begin by mapping the changing inflections of solidarity in recent feminist cultural theory, highlighting the range of theoretical components, investments and emphases. Next, we consider the various forms of solidarity presented and created by the Women’s March and the Women’s Strike, analysing the differences in terms of the extent of their reach and their political economy. We argue that both phenomena can be understood as reactions to, firstly, several decades of neoliberal impoverishment, which have now exposed neoliberal iterations of feminism as fundamentally inadequate; and secondly, and relatedly, the arrival of misogynistic and reactionary forms of nationalism. Finally, we show that different approaches to feminist solidarity, as well as an expansion of alliances, are necessary in order to extend contemporary feminism as an effective and large‐scale project. We therefore argue that feminist solidarity needs to retain its genealogical roots in left politics whilst being as plural as possible in practice
Turnover of passerine birds on islands in the Aegean Sea (Greece)
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73442/1/j.1365-2699.2007.01695.x.pd
From the Apennines to the Alps: recent range expansion of the crested porcupine Hystrix cristata L., 1758 (Mammalia: Rodentia: Hystricidae) in Italy
In the last few decades, the crested porcupine (Hystrix cristata L., 1758) showed a marked range expansion in Italy. Published and unpublished material was collected to reconstruct this phenomenon. Data were gathered by means of: (i) specific papers on crested porcupine distribution and more generic books and articles, (ii) expert collaboration in various Italian regions and (iii) information from the national Vertebrates mailing list. Until the 1970s, H. cristata was only present in Central and Southern Italy, mostly in the western part. Since 1978, the porcupine has been protected by Italian national law. The species first crossed the Apennines from the Tyrrhenian coast to the Marche, where the expansion to the north may have begun, and then reached the northernmost regions. An analysis of the potential distribution of the species was performed in a species distribution modeling framework (Maxent). The model suggested a high suitability of most of the Central and Southern Italian Peninsula for H. cristata, including the two major islands. Northern Italy proved suitable for the species' establishment only in some central and western areas of the Po Valley. The core areas of the Apennines and of the Alps, as well as some areas characterized by low annual rainfall, were predicted as unsuitable. Historical and social factors related to the progressive urbanization and the consequent abandonment of the traditional land use in mountain landscapes probably helped the re-expansion of forests and uncultivated fields. Three introduced populations have been detected in Sardinia, Liguria and the province of Varese. In order to make the data collected easily consultable and to give people the opportunity to contribute to a continuous updating of the distributional map of the species, a web page dedicated to H. cristata was set up, in the framework of an open-source wildlife mapping project. © 2013 Unione Zoologica Italiana
A multi-element psychosocial intervention for early psychosis (GET UP PIANO TRIAL) conducted in a catchment area of 10 million inhabitants: study protocol for a pragmatic cluster randomized controlled trial
Multi-element interventions for first-episode psychosis (FEP) are promising, but have mostly been conducted in non-epidemiologically representative samples, thereby raising the risk of underestimating the complexities involved in treating FEP in 'real-world' services
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