Tag-KEM/DEM: A New Framework for Hybrid Encryption

This paper presents a novel framework for the generic construction of hybrid encryption schemes which produces more efficient schemes than the ones known before. A previous framework introduced by Shoup combines a key encapsulation mechanism (KEM) and a data encryption mechanism (DEM). While it is sufficient to require both components to be secure against chosen ciphertext attacks (CCA-secure), Kurosawa and Desmedt showed a particular example of KEM that is not CCA-secure but can be securely combined with a specific type of CCA-secure DEM to obtain a more efficient, CCA-secure hybrid encryption scheme. There are also many other efficient hybrid encryption schemes in the literature that do not fit into Shoup’s framework. These facts serve as motivation to seek another framework. The framework we propose yields more efficient hybrid scheme, and in addition provides insightful explanation about existing schemes that do not fit into the previous framework. Moreover, it allows immediate conversion from a class of threshold public-key encryption to a threshold hybrid one without considerable overhead, which may not be possible in the previous approach.     

Motherhood and nursing stimulate c-FOS expression in the rabbit forebrain.

Mother rabbits nurse once daily with circadian periodicity. The authors investigated brain structures involved in regulating this activity by quantifying c-FOS-immunoreactive (IR) cells in the forebrain of: (1) mothers killed on postpartum Day 1 (PPD 1) after nursing (Group 1) or not given pups (Group 2); (2) mothers killed on PPD 7 after nursing (Group 3) or not given pups on such day (Group 4); (3) unmated virgins (Group 5). Groups 1 through 4 showed similar numbers of c-FOS-IR cells in the preoptic area, an amount around three to fourfold larger than that found in virgins. Nursing increased, on PPD 1 and 7, c-FOS-IR cell number in the lateral septum and paraventricular and supraoptic nuclei. No differences were seen among Groups 1 through 5 in the suprachiasmatic nucleus. In the ventromedial hypothalamus virgins had more c-FOS-IR cells compared with Groups 1 and 2. Results suggest that specific forebrain structures participate in regulating particular aspects of rabbit maternal behavior: the POA and LS seem associated with the establishment of motherhood and the magnocellular nuclei with the occurrence of milk letdown. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reduced-order model feedback control design: numericalimplementation in a thin shell model

Reduced-order models employing the Lagrange and popular proper orthogonal decomposition (POD) reduced-basis methods in numerical approximation and feedback control of systems are presented and numerically tested. The system under consideration is a thin cylindrical shell with surface-mounted piezoceramic actuators. Donnell-Mushtari equations, modified to include Kelvin-Voigt damping, are used to model the system dynamics. Basis functions constructed from Fourier polynomials tensored with cubic splines are employed in the Galerkin expansion of the full-order model. Reduced-basis elements are then formed from full order approximations of the exogenously excited shell taken at different time instances. Numerical examples illustrating the features of the reduced-basis methods are presented. As a first step toward investigating the behavior of the methods when implemented in physical systems, the use of reduced-order model feedback control gains in the full order model is considered and numerical examples are presented     

Countries to benefit most from early transition to hydrogen fueled transportation: Merit factor analysis

The world consists of many countries having differences in many areas, ranging from size to economic level, from population to education, etc. Consequently, they are not going to convert to hydrogen‐fueled transportation at the same time. Some will have the right conditions to convert to clean hydrogen transportation early, and other countries will have conditions which will result in a delay in conversion to hydrogen‐fueled transportation. In order to find out which countries are the candidates for early conversion to hydrogen fueled transportation and which countries might convert to hydrogen‐fueled transportation later, an analysis has been carried out covering almost all of the countries in the world. Results indicate that the countries with higher income per capita and smaller size could convert to hydrogen‐fueled transportation earlier. Copyright © 2013 John Wiley & Sons, Ltd.     

Magnetic and Structural Characterization of IrO2 and Co:IrO2 Samples Synthesized via Pechini Method

Diluted Magnetic Oxide Semiconductors (DMOS) are oxides that combine two important properties for applications in spintronics: the capacity to control conductivity and ferromagnetism. Obtaining new materials that exhibit simultaneously these behaviors is challenging. In this paper, we investigate whether it is possible to use IrO₂ and Co:IrO₂ as a DMOS by studying their magnetic and structural characteristics. The samples were synthesized by the Pechini method, and characterized by X-ray diffraction and magnetization measurements. These samples were doped with 0 to 10 mol% Co concentrations. The X-ray diffraction was analyzed using the Rietveld refinement procedure which showed that all cobalt (Co²⁺) introduced into the IrO₂ lattice replace Ir⁴⁺ ions until the dopants concentration of about 10 mol%, and no phase segregation was observed for the highest dopant concentration investigated. Magnetization measurements as a function of temperature and applied magnetic field were performed on these samples. The results show a paramagnetic behavior, despite of the high Co concentration.     

The development of competencies in manufacturing engineering by means of a deep-drawing tool

This paper presents a Computer-aided System known as the deep-drawing tool applied to the resolution of a combined deep-drawing and ironing process. The system allows the user for selecting input data for getting the formability of material to deep-drawing, selecting the process that provides the best solution from a technological perspective, optimizing the process for material waste, knowing the influence of the punch in the results and considering the process cost. In this manner, the tool allows developing competencies to students that apply scientific, technological, mathematical, economical and sustainable knowledge, with a global vision of the manufacturing processes and conciliating research and teaching. An industrial case has been considered and the proposed Computer-aided System has been tested with a brass alloy to demonstrate the system’s capability. The results obtained show significant improvements in the two variables analyzed, namely, total process time and total manufacturing cost. These aspects provide competencies to students in the manufacturing environment.     

Comparative formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in creatinine/phenylalanine and creatinine/phenylalanine/4-oxo-2-nonenal reaction mixtures

The comparative formation of the heterocyclic aromatic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in both creatinine/phenylalanine (CRN/Phe) and creatinine/phenylalanine/4-oxo-2-nonenal (CRN/Phe/ON) systems was studied to analyse the ability of lipid-derived reactive carbonyls to promote PhIP formation. Although PhIP was produced to some extent in the CRN/Phe system, the presence of the oxidized lipid increased considerably the amount of PhIP produced. This increase seemed to be a consequence of the decrease in the E_a of the reaction when the lipid was present, which diminished from 112.9 to 80.9 kJ/mol. On the other hand, the addition of the lipid did not seem to produce PhIP by an alternative mechanism because PhIP was formed analogously in both CRN/Phe and CRN/Phe/ON systems as a function of pH, creatinine concentration, phenylalanine concentration, time, temperature, oxygen concentration in the reaction atmosphere, and the addition of different amounts of ammonia. All these results suggest that the ability of lipid oxidation products to produce PhIP is related to their capacity to induce the Strecker degradation of phenylalanine to phenylacetaldehyde. Therefore, any other reactive carbonyl compound that can produce the Strecker degradation of phenylalanine should also be considered as a potential inducer of PhIP formation under appropriate conditions.