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Sandra Díez-Villares,1– 3 Juan Pellico,4,5 Noemí Gómez-Lado,6 Santiago Grijalvo,7,8 Sandra Alijas,1 Ramon Eritja,7,8 Fernando Herranz,5,9 Pablo Aguiar,6 María de la Fuente1,2 1Nano-Oncology and Translational Therapeutics group, Health Research Institute of Santiago de Compostela (IDIS), SERGAS, Santiago de Compostela, 15706, Spain; 2Biomedical Research Networking Center on Oncology (CIBERONC), Madrid, 28029, Spain; 3University of Santiago de Compostela (USC), Santiago de Compostela, 15782, Spain; 4School of Biomedical Engineering & Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, SE1 7EH, UK; 5Biomedical Research Networking Center on Respiratory Diseases (CIBERES), Madrid, 28029, Spain; 6Nuclear Medicine Department and Molecular Imaging Group, Health Research Institute of Santiago de Compostela (IDIS), SERGAS, Santiago de Compostela, 15706, Spain; 7Institute for Advanced Chemistry of Catalonia (IQAC), Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, E-08034, Spain; 8Biomedical Research Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, 28029, Spain; 9NanoMedMol Group, Instituto de Química Medica (IQM),Consejo Superior de Investigaciones Científicas (CSIC), Madrid, 28006, SpainCorrespondence: María de la FuenteNano-Oncology Unit and Translational Therapeutics Unit, Health Research Institute of Santiago de Compostela (IDIS), Clinical University Hospital (CHUS), Building C, Floor − 2, Lab 18, Travesía da Choupana s/n, Santiago de Compostela, ES15706, SpainTel +34 981 955 704Email maria.de.la.fuente.freire@sergas.esBackground and Purpose: Non-invasive imaging methodologies, especially nuclear imaging techniques, have undergone an extraordinary development over the last years. Interest in the development of innovative tracers has prompted the emergence of new nanomaterials with a focus on nuclear imaging and therapeutical applications. Among others, organic nanoparticles are of the highest interest due to their translational potential related to their biocompatibility and biodegradability. Our group has developed a promising new type of biocompatible nanomaterials, sphingomyelin nanoemulsions (SNs). The aim of this study is to explore the potential of SNs for nuclear imaging applications.Methods: Ready-to-label SNs were prepared by a one-step method using lipid derivative chelators and characterized in terms of their physicochemical properties. Stability was assessed under storage and after incubation with human serum. Chelator-functionalized SNs were radiolabeled with 67Ga and 68Ga, and the radiochemical yield (RCY), radiochemical purity (RCP) and radiochemical stability (RCS) were determined. Finally, the biodistribution of 67/68Ga-SNs was evaluated in vivo and ex vivo.Results: Here, we describe a simple and mild one-step method for fast and efficient radiolabeling of SNs with 68Ga and 67Ga radioisotopes. In vivo experiments showed that 67/68Ga-SNs can efficiently and indistinctly be followed up by PET and SPECT. Additionally, we proved that the biodistribution of the 67/68Ga-SNs can be conveniently modulated by modifying the surface properties of different hydrophilic polymers, and therefore the formulation can be further adapted to the specific requirements of different biomedical applications.Conclusion: This work supports 67/68Ga-SNs as a novel probe for nuclear imaging with tunable biodistribution and with great potential for the future development of nanotheranostics.Keywords: sphingomyelin nanoemulsions, biodistribution, gallium-68/67, nuclear imaging, nanotheranostics

Localization and mapping in indoor environments, such as airports and hospitals, are key tasks for almost every robotic platform. Some researchers suggest the use of Range-Only (RO) sensors based on WiFi (Wireless Fidelity) technology with SLAM (Simultaneous Localization And Mapping) techniques to solve both problems. The current state of the art in RO SLAM is mainly focused on the filtering approach, while the study of smoothing approaches with RO sensors is quite incomplete. This paper presents a comparison between filtering algorithms, such as EKF and FastSLAM, and a smoothing algorithm, the SAM (Smoothing And Mapping). Experimental results are obtained in indoor environments using WiFi sensors. The results demonstrate the feasibility of the smoothing approach using WiFi sensors in an indoor environment. [ABSTRACT FROM PUBLISHER]

A Lie system is a non-autonomous system of first-order differential equations possessing a superposition rule, i.e. a map expressing its general solution in terms of a generic finite family of particular solutions and some constants. Lie-Hamilton systems form a subclass of Lie systems whose dynamics is governed by a curve in a finite-dimensional real Lie algebra of functions on a Poissonmanifold. It is shown that Lie-Hamilton systems are naturally endowed with a Poisson coalgebra structure. This allows us to devise methods for deriving in an algebraic way their constants of motion and superposition rules. We illustrate our methods by studying Kummer-Schwarz equations, Riccati equations, Ermakov systems and Smorodinsky-Winternitz systems with timedependent frequency. [ABSTRACT FROM AUTHOR]

The Lie—Poisson algebra so( N + 1) and some of its contractions are used to construct a family of superintegrable Hamiltonians on the N-dimensional spherical, Euclidean, hyperbolic, Minkowskian, and (anti-)de Sitter spaces. We firstly present a Hamiltonian which is a superposition of an arbitrary central potential with N arbitrary centrifugal terms. Such a system is quasi-maximally superintegrable since this is endowed with 2 N — 3 functionally independent constants of motion (plus the Hamiltonian). Secondly, we identify two maximally superintegrable Hamiltonians by choosing a specific central potential and finding at the same time the remaining integral. The former is the generalization of the Smorodinsky—Winternitz system to the above six spaces, while the latter is a generalization of the Kepler—Coulomb potential, for which the Laplace—Runge—Lenz N vector is also given. All the systems and constants of motion are explicitly expressed in a unified form in terms of ambient and polar coordinates as they are parametrized by two contraction parameters (curvature and signature of the metric). [ABSTRACT FROM AUTHOR]

We show that schematic su(2)⊕h3 interaction Hamiltonians, where su(2) plays the role of the pseudospin algebra of fermion operators and h3 is the Heisenberg algebra for bosons, are closely related to certain nonlinear models defined on a single quantum algebra suq(2) of quasifermions. In particular, suq(2) analogues of the Da Providencia–Schütte and extended Lipkin models are presented. We analyze the connection between q and the physical parameters of the fermion–boson system and, using polynomial algebras, discuss the integrability properties of the interaction Hamiltonians. [ABSTRACT FROM AUTHOR]

A global model of the q deformation for the quasiorthogonal Lie algebras generating the groups of motions of the four-dimensional affine Cayley–Klein (CK) geometries is obtained starting from the three-dimensional deformations. It is shown how the main algebraic classical properties of the CK systems can be implemented in the quantum case. Quantum deformed versions either of the space–time or space symmetry algebras [Poincaré (3+1), Galilei (3+1), 4-D Euclidean as well as others] appear in this context as particular cases. For some of these classical algebras several q deformations are directly obtained. [ABSTRACT FROM AUTHOR]

An embedding method to get q-deformations for the nonsemisimple algebras generating the motion groups of N-dimensional flat spaces is presented. This method gives a global and simultaneous scheme of q-deformation for all iso( p, q) algebras and for those obtained from them by some Inönü-Wigner contractions, such as the N-dimensional Euclidean, Poincaré, and Galilei algebras. [ABSTRACT FROM AUTHOR]