Generalized Wasserstein distance and its application to transport equations with source

In this article, we generalize the Wasserstein distance to measures with different masses. We study the properties of such distance. In particular, we show that it metrizes weak convergence for tight sequences. We use this generalized Wasserstein distance to study a transport equation with source, in which both the vector field and the source depend on the measure itself. We prove existence and uniqueness of the solution to the Cauchy problem when the vector field and the source are Lipschitzian with respect to the generalized Wasserstein distance

Existence and approximation of probability measure solutions to models of collective behaviors

In this paper we consider first order differential models of collective behaviors of groups of agents based on the mass conservation equation. Models are formulated taking the spatial distribution of the agents as the main unknown, expressed in terms of a probability measure evolving in time. We develop an existence and approximation theory of the solutions to such models and we show that some recently proposed models of crowd and swarm dynamics fit our theoretic paradigm.Comment: 31 pages, 1 figur

Polynomial multiplication over binary finite fields : new upper bounds

When implementing a cryptographic algorithm, efficient operations have high relevance both in hardware and in software. Since a number of operations can be performed via polynomial multiplication, the arithmetic of polynomials over finite fields plays a key role in real-life implementations\u2014e.g., accelerating cryptographic and cryptanalytic software (pre- and post-quantum) (Chou in Accelerating pre-and post-quantum cryptography. Ph.D. thesis, Technische Universiteit Eindhoven, 2016). One of the most interesting papers that addressed the problem has been published in 2009. In Bernstein (in: Halevi (ed) Advances in Cryptology\u2014CRYPTO 2009: 29th Annual International Cryptology Conference, Santa Barbara, CA, USA, August 16\u201320, 2009. Proceedings, pp 317\u2013336. Springer Berlin Heidelberg, Berlin, Heidelberg, 2009), Bernstein suggests to split polynomials into parts and presents a new recursive multiplication technique which is faster than those commonly used. In order to further reduce the number of bit operations (Bernstein in High-speed cryptography in characteristic 2: minimum number of bit operations for multiplication, 2009. http://binary.cr.yp.to/m.html) required to multiply n-bit polynomials, researchers adopt different approaches. In CMT: Circuit minimization work. http://www.cs.yale.edu/homes/peralta/CircuitStuff/CMT.html a greedy heuristic has been applied to linear straight-line sequences listed in Bernstein (High-speed cryptography in characteristic 2: minimum number of bit operations for multiplication, 2009. http://binary.cr.yp.to/m.html). In 2013, D\u2019angella et al. (Applied computing conference, 2013. ACC\u201913. WEAS. pp. 31\u201337. WEAS, 2013) skip some redundant operations of the multiplication algorithms described in Bernstein (in: Halevi (ed) Advances in Cryptology\u2014CRYPTO 2009: 29th Annual International Cryptology Conference, Santa Barbara, CA, USA, August 16\u201320, 2009. Proceedings, pp 317\u2013336. Springer Berlin Heidelberg, Berlin, Heidelberg, 2009). In 2015, Cenk et al. (J Cryptogr Eng 5(4):289\u2013303, 2015) suggest new multiplication algorithms. In this paper, (a) we present a \u201ck-1\u201d-level recursion algorithm that can be used to reduce the effective number of bit operations required to multiply n-bit polynomials, and (b) we use algebraic extensions of F 2 combined with Lagrange interpolation to improve the asymptotic complexity

O tema água em livros didáticos de ciências e questões controversas

Entre os temas relacionados à temática ambiental o tema água tem sido enfatizado nos currículos escolares e tem sido explorado pelos livros didáticos. A água tem inúmeros significados tanto em relação a sua importância como um elemento natural quanto em seus sentidos simbólicos para diferentes sociedades. Essa multiplicidade de contextos e significados caracterizam este tema como controverso. Os temas controversos são apontados como possibilidades instigantes para o trabalho em sala de aula. Partindo desses pressupostos, o objetivo dessa investigação foi o de procurar identificar se estes materiais didáticos abordam controvérsias relacionadas com este tema. A análise temática realizada nos indicou que dentre todos os temas relacionados à água, somente os conteúdos ligados a construção de barragens eram abordados a partir da perspectiva dos temas controversos

Charcoal for the management of pruritus and uremic toxins in patients with chronic kidney disease

Purpose of review: Pruritus is an important, prevalent but often neglected symptom in patients with advanced chronic kidney disease (CKD) or on dialysis. This review addresses the use of activated charcoal and its analogs in the treatment of uremic pruritus, which can be a sign of uremic toxicity. Recent findings: When common causes are corrected and dialysis efficiency is optimized, pruritus is mainly ascribed to the retention of middle and protein-bound molecules, of which indoxyl sulfate and p-cresyl sulfate are the best studied. While hemodialysis and hemodiafiltration are of limited use, activated charcoal and its analogs offer interesting alternatives. Oral preparations are associated with symptom improvement and a better metabolic pattern, probably via a combination of absorption and modification of the intestinal microbiota. Large studies, in well phenotyped populations, are needed. Hemoperfusion, commonly used in poisoning and intoxication, could be an interesting alternative in hemodialysis patients. The treatment has proved promising in some preliminary and small studies; more research is now needed to test its validity. Summary: Oral activated charcoal and hemoperfusion can be proposed to patients with severe refractory pruritus based on positive, albeit scattered evidence. They also contribute to reducing uremic toxins. Research on their implementation associated with well established treatments is needed to understand whether they can be used as 'uremic detoxifiers'

Seasonal Phenology of Reptiles in a Mediterranean Environment (“Castel di Guido” Natural Park, Northern Latium, Italy)

The present work reports the seasonal phenology of the reptiles of the "Castel di Guido" Natural Park near Rome (Northern Latium, Italy). During field observations, between September 2014 and July 2016, transects were carried out along the ecotones of the park, in order to describe the period of seasonal activity of the reptiles present. The area is characterized by Mediterranean mesothermal climate. In the Mediterranean area, reptiles have a broader annual activity range than other European regions, greatly reducing winter latency. Reptile activities start very early, in some case it is possible to observe the snake Hierophis viridiflavus and lizards, such as Podarcis muralis and Podarcis siculus, in thermoregulation activity in the middle of winter. The mild climate that is recorded on average in autumn favors the activity in the period between September and December; Zamenis longissimus is observed regularly in October. Testudo hermanni mates regularly in autumn and it is active until the first decade of December. The research shows that during the winter period reptiles can be observed in activity; for some species, Chalcides chalcides, Podarcis sp., Hierophis viridiflavus, this seems to be a remarkable datum that broad considerably the annual phenology reported in the literature

Design and Fabrication of Terahertz Metallic Gratings on a Two-Wire Waveguide

In this study, we present the design, fabrication and experimental characterization of waveguide-integrated gratings operating at THz frequencie