Enhanced tunneling conductivity induced by gelation of attractive colloids

We show that the formation of a gel by conducting colloidal particles leads to a dramatic enhancement in bulk conductivity, due to inter-particle electron tunneling, combining predictions from molecular dynamics simulations with structural measurements in an experimental colloid system. Our results show how colloidal gelation can be used as a general route to huge enhancements of conductivity, and suggest a feasible way for developing cheap materials with novel properties and low metal content.Comment: 8 pages, 8 figures, 2 table

Goffman e l’antropologia applicata. Riflessioni su un progetto di ricerca-azione in un quartiere della diaspora etiope ed eritrea

The essay describes a direct experience of research-action in the context of Milano Porta Venezia, a local space of the global Ethiopian and Eritrean diaspora. I propose a reflection on the potentialities and the limits of Goffman’s performative model as a way to build a shared framework among social actors belonging to contrastive identity models. The purpose of this paper is to highlight the need for a toolbox suitable to meet the challenges of anthropology applied to the public space

Non-linear MRD codes from cones over exterior sets

By using the notion of $d$-embedding $\Gamma$ of a (canonical) subgeometry $\Sigma$ and of exterior set with respect to the $h$-secant variety $\Omega_{h}(\mathcal{A})$ of a subset $\mathcal{A}$, $0 \leq h \leq n-1$, in the finite projective space $\mathrm{PG}(n-1,q^n)$, $n \geq 3$, in this article we construct a class of non-linear $(n,n,q;d)$-MRD codes for any $2 \leq d \leq n-1$. A code $\mathcal{C}_{\sigma,T}$ of this class, where $1\in T \subset \mathbb{F}_q^*$ and $\sigma$ is a generator of $\mathrm{Gal}(\mathbb{F}_{q^n}|\mathbb{F}_q)$, arises from a cone of $\mathrm{PG}(n-1,q^n)$ with vertex an $(n-d-2)$-dimensional subspace over a maximum exterior set $\mathcal{E}$ with respect to $\Omega_{d-2}(\Gamma)$. We prove that the codes introduced in [Cossidente, A., Marino, G., Pavese, F.: Non-linear maximum rank distance codes. Des. Codes Cryptogr. 79, 597--609 (2016); Durante, N., Siciliano, A.: Non-linear maximum rank distance codes in the cyclic model for the field reduction of finite geometries. Electron. J. Comb. (2017); Donati, G., Durante, N.: A generalization of the normal rational curve in $\mathrm{PG}(d,q^n)$ and its associated non-linear MRD codes. Des. Codes Cryptogr. 86, 1175--1184 (2018)] are appropriate punctured ones of $\mathcal{C}_{\sigma,T}$ and solve completely the inequivalence issue for this class showing that $\mathcal{C}_{\sigma,T}$ is neither equivalent nor adjointly equivalent to the non-linear MRD code $\mathcal{C}_{n,k,\sigma,I}$, $I \subseteq \mathbb{F}_q$, obtained in [Otal, K., \"Ozbudak, F.: Some new non-additive maximum rank distance codes. Finite Fields and Their Applications 50, 293--303 (2018).]

On the classification of low degree ovoids of Q+(5,q)Q^+(5,q)

Ovoids of the Klein quadric $Q^+(5,q)$ of $\mathrm{PG}(5,q)$ have been studied in the last 40 year, also because of their connection with spreads of $\mathrm{PG}(3,q)$ and hence translation planes. Beside the classical example given by a three dimensional elliptic quadric (corresponding to the regular spread of $\mathrm{PG}(3,q)$) many other classes of examples are known. First of all the other examples (beside the elliptic quadric) of ovoids of $Q(4,q)$ give also examples of ovoids of $Q^+(5,q)$. Another important class of ovoids of $Q^+(5,q)$ is given by the ones associated to a flock of a three dimensional quadratic cone. To every ovoid of $Q^+(5,q)$ two bivariate polynomials $f_1(x,y)$ and $f_2(x,y)$ can be associated. In this paper, we classify ovoids of $Q^+(5,q)$ such that $f_1(x,y)=y+g(x)$ and $\max\{deg(f_1),deg(f_2)\}<(\frac{1}{6.3}q)^{\frac{3}{13}}-1$, that is $f_1(x,y)$ and $f_2(x,y)$ have "low degree" compared with $q$.Comment: Submitted to Journal of Algebraic Combinatorics. arXiv admin note: substantial text overlap with arXiv:2203.1468

Surgical Implications of Ischemia Reperfusion Damage and Future Perspectives.

Flaps are often used in plastic and reconstructive surgery, and random pattern flaps were the first to be described. The indications for their use are numerous and include post-traumatic loss of su..

TiO2 Nanostructures and Nanocomposites for Sustainable Photocatalytic Water Purification

Water, together with energy and food, has been addressed as one of the main urgent problems of humanity. The conventional wastewater treatments suffer some limitations related to the effectiveness in decontamination (mechanical filtration), in the heavy use of chemicals (chlorination), or in elevation of operational costs and energy requirements (desalination and reverse osmosis). In this sense, new materials such as nanocomposites may overcome these issues taking advantage of the peculiar properties of materials at nanoscale. Research on novel nanotechnologies must bring advances in order to contrast and prevent water scarcity and pollution. In order to be effective, these nanotechnologies should run at low operational cost, even in places unequipped by strong infrastructures and in concert with conventional cheap methodologies

Sharp second-order regularity for widely degenerate elliptic equations

We consider local weak solutions of widely degenerate or singular elliptic PDEs of the type \begin{equation*} -\,\mathrm{div}\left((\vert Du\vert-\lambda)_{+}^{p-1}\frac{Du}{\vert Du\vert}\right)=f \,\,\,\,\,\,\, \text{in}\,\,\Omega, \end{equation*} where $\Omega$ is an open subset of $\mathbb{R}^{n}$ for $n\geq2$, $\lambda$ is a positive constant and $(\,\cdot\,)_{+}$ stands for the positive part. We establish some higher differentiability results, under essentially sharp conditions on the datum $f$. Our results improve the one contained in [8] for $\lambda=0$ and $p>2$, and give back a result similar to that in [12] for $1 < p \le 2$.Comment: This version contains a slight modification of the proof of Theorem 1.1, compared with the previous version. The conclusions of the teorem are the sam

Comprendere rotte migratorie fuori dall’accademia: metodi, linguaggi, potenzialità, limiti, posta in gioco.

Migration routes today are deeply questioning anthropology not only theoretically, but also, and above all, about its application. Anthropological research focused on the field of migration on one side "naturally" investigates and breaks through the political and public sphere, on the other contemplates social repercussions and forms of information and dissemination. For this reason, the analysis of migration routes often takes the form of intervention using languages, methodologies and communication channels alternative to the scientific publications, increasingly varied and straightforward. More frequently, techniques such as mapping tools, multi-site information and synchronised data platforms, visual documentation, migrant self-productions, etc. are used to document and analyse migration, involving new methods and communicative languages. Moreover, these works take place within interdisciplinary networks where the research and investigation methods are shared and overlapped with multiple communicative languages and styles. In recent decades, an analytical and communicative approach was built that, although rooted in the anthropological perspective, draws on both languages and unconventional technological tools to investigate and act on the migration routes. In this AP Forum we would like to engage with this parallel world to public anthropology, questioning us first of all about the ways in which professional skills are expressed in the field and on the reasons that led to move towards these styles and languages that re-articulate and overcome conventional forms of scientific communication. What are the methodological and positioning issues of the multiple action planning to deal anthropologically with the issue of migration routes? While on the one side it opens up to a range of research and intervention possibilities through which innovating the discipline itself, on the other conflicts and compromises are often generated by the application of an anthropological perspective. How this relationship between potentiality and limits articulate on such debated issue as migration routes? What tactics can be put in place to articulate this dialectic relationship? Finally, what is the stake that these consolidated ways of doing ethnography of migration bring into the field of questioning cultural and public anthropology? In particular, we are interested in affinities and discontinuities with respect to the conventional methods of research, asking ourselves if could be a dialogue (or not) and a possible way of collaboration between these different worlds of investigation and analysis

Skin graft donor site: a procedure for a faster healing

Background: The authors want to evaluate the efficacy of fibrillary tabotamp dressing in skin graftdonor site. A comparison was made with Vaseline gauzes. Tabotamp is an absorbable haemostatic product of Ethicon (Johnson and Johnson) obtained by sterile and oxidized regenerated cellulose (Rayon). It is used for mild to moderate bleeding. Materials and methods: 276 patients were subject to skin graft and divided into two group: Group A and Group B. The donor site of patients in Group A was medicated with fibrillary tabotamp, while the patients of Group B were medicated only with Vaseline gauze. We recorded infection, timing of healing, number of dressing change, the pain felt during and after the dressing change with visual analog scale (VAS) and a questionnaire. Results: Patients allocated in Group A healed faster than the Group B. Questionnaires and VAS analysis showed lower pain felt, lower intake of pain drugs and lower infection rate in the Group A than the Group B. Analysis of coast showed lower dressing change in Group A than the Group B. Conclusion: We believe that the use of tabotamp is a very viable alternative to improve healing. (www.actabiomedica.it)

On mm-ovoids of Q+(7,q)Q^+(7,q) with qq odd

In this paper, we provide a construction of $(q+1)$-ovoids of the hyperbolic quadric $Q^+(7,q)$, $q$ an odd prime power, by glueing $(q+1)/2$-ovoids of the elliptic quadric $Q^-(5,q)$. This is possible by controlling some intersection properties of (putative) $m$-ovoids of elliptic quadrics. It yields eventually $(q+1)$-ovoids of $Q^+(7,q)$ not coming from a $1$-system. Secondly, we also construct $m$-ovoids for $m \in \{ 2,4,6,8,10\}$ in $Q^+(7,3)$. Therefore we first investigate how to construct spreads of \pg(3,q) that have as many secants to an elliptic quadric as possible