Finite vertex algebras and nilpotence

I show that simple finite vertex algebras are commutative, and that the Lie conformal algebra structure underlying a reduced (i.e., without nilpotent elements) finite vertex algebra is nilpotent.Comment: 24 page

Sustainability of economic development and governance patterns in water management - an overview on the reorganisation of public utilities in Campania, Italy, under EU Framework Directive in the field of water policy (2000/60/CE)

The paper addresses the issue of sustainable development in water policy under the EU Framework Directive (2000/60/CE), and its implications on the governance of public utilities. Economic efficiency and environmental protection, far from being contradictory, are necessarily complementary in order to achieve the EU Water Framework Directive principles and objectives. Assuming public utilities as “environmental services”, the first part focuses on the theory of economic regulation for public utilities and innovative models of public/private governance for water management. In the second part, following the steps undertaken in Campania (since the first national reform in 1994), the paper tries to identify the main trends in water policies and management, resulting from the local governement efforts to comply with both environmental protection requirements under the EU Framework Directive and economic development programmes. The field of analysis is EU Structural Funds policy, as implemented by the Regional Operational Programme of Campania 2000-2006, which supports private and public investments in water infrastructures and management. According to the European regional policy, environmental protection requirements must be integrated into the definition and implementation of development programmes aimed at financing water infrastructures and innovative management of water services. The mid-term review on the performance of Structural Funds in Campania, shows that public/private partnership plays a crucial role in water policy, even for the integration of environmental concerns into the reorganisation of public utilities management.

Fish trade: needed, a new paradigm

Ensuring social sustainability in fish trade for small-scale fishers entails recognizing their economic contribution, and devoting public resources for policy

On our Doorstep. Simmel, Weber and the Making of Reality

Whether we like it or not whether we believe it or not 2020 will be the year that future historians will choose to mark as the advent of a new era The pandemic did not simply hit us harder than any previous crisis and God knows we had a few since the beginning of the XXI century It left us disoriented and stranded orphans of too many promises and proclamations while showing us mercilessly the limits of our knowledge and the extent of our hybris a mixture of inebriation and arrogance often found in Greek myths where it leads heroes such as Icarus to ruin The most powerful technology put to shame by an invisible what Thing Living being We just don t know four words that we d better keep in mind while reading the following pages The virus hasn t fit within our worldview right from the start and still there it is paralyzing global economies and exposing the flaws and shortcomings of the neoliberal ideology It makes it clear that no one survives on his her own that free markets bring forth indecent inequalities and scientists hold no definite truth but argue and squabble about numbers and theorie

Path-Fault-Tolerant Approximate Shortest-Path Trees

Let $G=(V,E)$ be an $n$-nodes non-negatively real-weighted undirected graph. In this paper we show how to enrich a {\em single-source shortest-path tree} (SPT) of $G$ with a \emph{sparse} set of \emph{auxiliary} edges selected from $E$, in order to create a structure which tolerates effectively a \emph{path failure} in the SPT. This consists of a simultaneous fault of a set $F$ of at most $f$ adjacent edges along a shortest path emanating from the source, and it is recognized as one of the most frequent disruption in an SPT. We show that, for any integer parameter $k \geq 1$, it is possible to provide a very sparse (i.e., of size $O(kn\cdot f^{1+1/k})$) auxiliary structure that carefully approximates (i.e., within a stretch factor of $(2k-1)(2|F|+1)$) the true shortest paths from the source during the lifetime of the failure. Moreover, we show that our construction can be further refined to get a stretch factor of $3$ and a size of $O(n \log n)$ for the special case $f=2$, and that it can be converted into a very efficient \emph{approximate-distance sensitivity oracle}, that allows to quickly (even in optimal time, if $k=1$) reconstruct the shortest paths (w.r.t. our structure) from the source after a path failure, thus permitting to perform promptly the needed rerouting operations. Our structure compares favorably with previous known solutions, as we discuss in the paper, and moreover it is also very effective in practice, as we assess through a large set of experiments.Comment: 21 pages, 3 figures, SIROCCO 201

On Pythagoras' theorem for products of spectral triples

We discuss a version of Pythagoras theorem in noncommutative geometry. Usual Pythagoras theorem can be formulated in terms of Connes' distance, between pure states, in the product of commutative spectral triples. We investigate the generalization to both non pure states and arbitrary spectral triples. We show that Pythagoras theorem is replaced by some Pythagoras inequalities, that we prove for the product of arbitrary (i.e. non-necessarily commutative) spectral triples, assuming only some unitality condition. We show that these inequalities are optimal, and provide non-unital counter-examples inspired by K-homology.Comment: Paper slightly shortened to match the published version; Lett. Math. Phys. 201

A rare case of leiomyoma of the bladder

Bladder leiomyoma is a benign tumour of the bladder and constitute <0.5% of all bladder tumors. We report a clinical case of a 51‑year‑old female who presented with with symptomatic bladder leiomyoma. An ultrasound examination showed well-defined bladder leiomyoma in the right posterior bladder wall, which was excised through a transurethral resection. The pathologic diagnosis was bladder leiomyoma

Study of the motions and nacelle accelerations of the windcrete floating offshore wind turbine according to the IEC 64100-3 procedure

Floating offshore wind technology is yet to establish a share in the renewable energy market, so far just a few commercial projects exist and many new concepts are being developed and tested. During this stage, simulation soft-wares like FAST are specially useful as they accelerate the development phase of the project, allowing the developers to understand the behaviour of their concepts under different conditions before constructing and testing prototypes. In this work the motions and nacelle accelerations of the Windcrete concept will be studied using FAST and the metocean data of two site

Interlayer Shear Failure Evolution with Different Test Equipments

AbstractThis research analyses the relationship between several configurations, failure mechanisms and states of stress imposed by testing machines, comparing the results of two devices. It focalizes on the evolution of numerous tests, performed on identical specimens, and reports the correspondent response curves obtained with two devices suitably designed to cover two kind of devices used in recent years and modified to ensure the comparison between the outcomes.The observation of a regular trend in the results suggests a strict relationship between them and the specimens’ features and also warrants the statistic reliability of the testing machines