On the lower semicontinuous envelope of functionals defined on polyhedral chains

In this note we prove an explicit formula for the lower semicontinuous envelope of some functionals defined on real polyhedral chains. More precisely, denoting by $H \colon \mathbb{R} \to \left[ 0,\infty \right)$ an even, subadditive, and lower semicontinuous function with $H(0)=0$, and by $\Phi_H$ the functional induced by $H$ on polyhedral $m$-chains, namely \Phi_{H}(P) := \sum_{i=1}^{N} H(\theta_{i}) \mathcal{H}^{m}(\sigma_{i}), \quad\mbox{for every }P=\sum_{i=1}^{N} \theta_{i} [[ \sigma_{i} ]] \in\mathbf{P}_m(\mathbb{R}^n), we prove that the lower semicontinuous envelope of $\Phi_H$ coincides on rectifiable $m$-currents with the $H$-mass \mathbb{M}_{H}(R) := \int_E H(\theta(x)) \, d\mathcal{H}^m(x) \quad \mbox{ for every } R= [[ E,\tau,\theta ]] \in \mathbf{R}_{m}(\mathbb{R}^{n}). Comment: 14 page

Breaking Consensus, Transforming Metabolisms : Notes on direct-action against fossil fuels through Urban Political Ecology

This article discusses the politics of “direct- action” against fossil fuels put forward by climate justice movements, focusing in particular on the tactic of the blockade. Drawing on the conceptual toolkit of Urban Political Ecology, the argument moves from a critique of the consensual regime of climate change governance to highlight conflict and dissent as central forces for the transformation of the socio-ecological metabolisms structuring the capitalist urbanization of nature—of which fossil fuels constitute the lifeblood. This approach shifts the debate around climate change politics from an issue of technological transition to one of metabolic transformation. On this basis, the article proposes a characterization of direct-action against fossil fuels as expressions of metabolic activism: instances of grassroots eco-political engagement that aim to break consensus by disrupting capitalist-driven metabolic relations while also experimenting with alternative values, knowledges, spaces, and socio-material relations. To ground these reflections, the article offers an account of the Swedish climate justice coalition Fossilgasfällan and of its successful three-year campaign, culminated in a blockade, to halt the expansion of the gas terminal of Gothenburg port

Social Economy as Antidote to Criminal Economy: How Social Cooperation is Reclaiming Commons in the Context of Campania’s Environmental Conflicts

This article contributes to ongoing debates on how bottom-up social cooperation can halt and reverse processes of environmental and human degradation, dispossession and impoverishment, by proposing a synchronization of resistance and of commoning practices. The article moves from the empirical case of social and ecological conflicts currently unfolding in the so-called Land of Fires, an area in Southern Italy infamous for the socio-environmental impacts of two decades of waste disposal, mismanagement and contamination. Within this context, a coalition of grassroots movements is struggling to resist livelihoods degradation through an alliance with anti-Mafia social cooperatives. We provide an in-depth analysis of emerging social and economic networks that connect the strategies of grassroots movements for environmental justice with the work of social cooperatives that reclaim lands and assets confiscated to Mafia. The interests of environmental activists meet the interests of social cooperatives at the crossroad of territory reclamation with the spheres of social and economic production and reproduction. Framing the case as a cultural and physical re-appropriation of territory, we provide an analysis of strategies and limits for a symbolic and practical project of social re-appropriation of the commons

Cyclic dipeptides produced by marine sponge-associated bacteria as quorum sensing signals.

Four bacterial strains belonging to the genera Vibrio, Pseudoalteromonas and Photobacterium were isolated from the marine sponges Dysidea avara and Geodia cynodium. A Bacillus strain was isolated from Ircinia variabilis. A screening of molecules involved in quorum sensing (QS) was carried out by TLC-overlay and a new "plate T-streak" test. To analyze quorum quenching (QQ), a plate T-streak was performed with Chromobacterium violaceum. Strains of Vibrio isolated from both marine sponges and a strain of Photobacterium isolated from G. cynodium, activated QS bioreporters. A strain of Pseudoalteromonas isolated from D. avara showed QQ activity. Finally, it is reported that cyclic dipeptides isolated from strains of Vibrio sp. and Bacillus sp. (isolated from D. avara and I. variabilis, respectively) were involved in the QS mechanism. The simultaneous presence of bacteria that showed contrasting responses in bioassays for QS signal molecule synthesis in marine sponges could add an interesting dimension to the signalling interactions which may be happening in sponges

PINK1 homozygous W437X mutation in a patient with apparent dominant transmission of parkinsonism.

We analyzed the PINK1 gene in 58 patients with early-onset Parkinsonism and detected the homozygous mutation W437X in 1 patient. The clinical phenotype was characterized by early onset (22 years of age), good re- sponse to levodopa, early fluctuations and dyskinesias, and psychiatric symptoms. The mother, heterozygote for W437X mutation, was affected by Parkinson’s disease and 3 further relatives were reported affected, according to an autosomal dominant transmission

A Novel Quick and Easy Test for Radial Artery Occlusion With the Laser Doppler Scan

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Further in vitro biological activity evaluation of amino-, thio- and ester-derivatives of avarol

The acetylcholinesterase inhibitory and/or antitumour activities of amino-, thio-and ester-derivatives of avarol selected were evaluated for the first time at in vitro conditions. Avarol-3',4'-dithioglycol (1) and avarol-4'-(3) mercaptopropionic acid (3) were shown to be the best inhibitors of the enzyme tested (0.50 mu g and IC50 0.05mM and 0.50 mg and IC50 0.12 mM, respectively), while 4'-tryptamine-avarone (9) and avarol-3'-(3) mercaptopropionic acid (2) exhibited the highest cytotoxicity against the human breast T-47D cancer cell line (IC50 0.66 mu g/mL and 1.25 mu g/mL, respectively). According to experimental data obtained, the sesquiterpenoid hydroquinone structure of bioactive avarol derivatives may inspire development of new pharmacologically useful substances to be used in the treatment of Alzheimer's disease and/or human breast tumour

Physics-informed neural networks approach for 1D and 2D Gray-Scott systems

AbstractNowadays, in the Scientific Machine Learning (SML) research field, the traditional machine learning (ML) tools and scientific computing approaches are fruitfully intersected for solving problems modelled by Partial Differential Equations (PDEs) in science and engineering applications. Challenging SML methodologies are the new computational paradigms named Physics-Informed Neural Networks (PINNs). PINN has revolutionized the classical adoption of ML in scientific computing, representing a novel class of promising algorithms where the learning process is constrained to satisfy known physical laws described by differential equations. In this paper, we propose a PINN-based computational study to deal with a non-linear partial differential equations system. In particular, using this approach, we solve the Gray-Scott model, a reaction–diffusion system that involves an irreversible chemical reaction between two reactants. In the unstable region of the model, we consider some a priori information related to dynamical behaviors, i. e. a supervised approach that relies on a finite difference method (FDM). Finally, simulation results show that PINNs can successfully provide an approximated Grey-Scott system solution, reproducing the characteristic Turing patterns for different parameter configurations

Mineral compositions of some selected centaurea species from Turkey

Centaurea calolepis Boiss., Centaurea lydia Boiss. and Centaurea polyclada DC. were investigated for major minerals and trace elements by X-ray fluorescence spectrometry. Calcium and potassium were found in maximum concentrations in Centaurea species. The results revealed that the concentrations of iron, manganese and zinc were found to be high in C. calolepis. On the other hand, copper, magnesium and phosphorous were found in higher concentrations in C. polyclada. Mineral composition of Centaurea species, will be descriptive in terms of the traditional use of this species. In addition, C. calolepis, C. lydia and C. polyclada may be utilized in nutraceuticals as potential natural sources of major minerals and trace elements