King Juan Carlos University
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Introduction to Corporations II - Marketing topic explanation - Business Administration Degree
No full textAssociations between pleasant events, activity restriction, stressors, and blood pressure in caregivers of persons with dementia
No full textObjectives: Caring for a relative with dementia is associated with adverse consequences for cardiovascular health. Cognitive and behavioral factors, such as high perceived activity restriction and low frequency of pleasant events have been found to be associated with higher levels of blood pressure, but the role these variables play in the stress and coping process remains understudied. The objective of this study is to analyze the associations between behavioral and psychological symptoms of dementia, activity restriction, frequency of pleasant events, and mean arterial pressure. Design: Face-to-face interviews and cross-sectional analyses. Setting: Social services, healthcare centers, and adult day services of Comunidad de Madrid, Spain. Participants: One hundred and two family caregivers of a spouse or parent with dementia. Measurements: Apart from various sociodemographic and health-related variables, behavioral and psychological symptoms of dementia, activity restriction, and frequency of leisure activities were assessed. In addition, measurement of blood pressure levels was conducted through an electronic sphygmomanometer. Results: The obtained model suggests that there is a significant indirect association between behavioral and psychological symptoms of dementia and mean arterial pressure through activity restriction and frequency of pleasant events. Conclusions: The findings of this study provide preliminary support for a potential indirect effect between behavioral and psychological symptoms of dementia and blood pressure, through the effects of behavioral and psychological symptoms of dementia on the caregivers' levels of activity restriction and frequency of pleasant activities. Our manuscript provides additional support for the pleasant events and activity restriction model (Mausbach et al., 2011; Chattillion et al., 2013), by highlighting the importance of considering caregiving stressors as a source of caregivers' activity restriction in the theoretical framework of the model
Haptically Assisted Connection Procedure for the Reconstruction of Dendritic Spines
No full textDendritic spines are thin protrusions that cover the dendritic surface of numerous neurons in the brain and whose function seems to play a key role in neural circuits. The correct segmentation of those structures is difficult due to their small size and the resulting spines can appear incomplete. This paper presents a four-step procedure for the complete reconstruction of dendritic spines. The haptically driven procedure is intended to work as an image processing stage before the automatic segmentation step giving the final representation of the dendritic spines. The procedure is designed to allow both the navigation and the volume image editing to be carried out using a haptic device. A use case employing our procedure together with a commercial software package for the segmentation stage is illustrated. Finally, the haptic editing is evaluated in two experiments; the first experiment concerns the benefits of the force feedback and the second checks the suitability of the use of a haptic device as input. In both cases, the results shows that the procedure improves the editing accuracy
Global solutions versus finite time blow-up for the supercritical fast diffusion equation with inhomogeneous source
No full textSolutions in self-similar form, either global in time or presenting finite time blow-up, to the supercritical fast diffusion equation with spatially inhomogeneous source ∂tu = Δum + |x| σup, (x, t) ∈ RN × (0, ∞) with mc = (N − 2)+ N ≤ m max 1 + σ(1 − m) 2 , 1 are considered. It is proved that global self-similar solutions with the specific tail behavior u(x, t) ∼ C(m)|x| −2/(1−m), as |x|→∞ exist exactly for p ∈ (pF (σ), ps(σ)), where pF (σ) = m + σ + 2N , ps(σ) = m(N+2σ+2) N−2 , N ≥ 3, ∞, N ∈ {1, 2}, are the renowned Fujita and Sobolev critical exponents. In contrast, it is shown that self-similar solutions presenting finite time blow-up exist for any σ ∈ (−2, 0) and p as above, but do not exist for any σ ≥ 0 and p ∈ (pF (σ), ps(σ)). We stress that all these results are new also in the homogeneous case σ = 0
Morphological and Molecular Characterization of Kochinema farodai Baqri and Bohra, 2001 (Dorylaimida: Nordiidae) from California, with the First Molecular Study and an Updated Taxonomy of the Genus
No full textSimple Summary In this paper, a population of a free-living nematode collected from Northern California (USA) is identified and studied. The aim of the present work is to characterize a Californian population of the nematode genus Kochinema, with morphological and molecular methods. In addition, a revision of this genus is also provided including an updated diagnosis, a list of species, a key to species identification, and a compendium of their main morphometrics and distribution data. This paper deals with the morphological and molecular characterization of Kochinema farodai Baqri and Bohra, 2001, with an integrative approach. The finding of K. faroidai in California is a remarkable biogeographical novelty, as it is the first American record of the species. Molecular data herein obtained represent the first molecular study of the genus Kochinema. Furthermore, scanning electron microscopy (SEM) observations of a member of Kochinema are provided for the first time. Additionally, this contribution provides new insights into the phylogeny and taxonomy of the nematode genus Kochinema. A brief historical outline of the matter is presented. Then, the morphological pattern of the genus is revised and illustrated, the anterior position of amphids, whose opening is located on lateral lip, being its most relevant diagnostic feature. The phylogenetic analysis inferred from D2-D3 expansion segments of 28S rRNA gene shows that Kochinema clustered together with other dorylaimid species characterized by the absence of pars refringens vaginae and that it does not share a recent common ancestor with other members of the family Nordiidae. A likely polyphyly of the family Nordiidae is confirmed. Finally, an updated taxonomy of the genus is proposed, including a revised diagnosis, a list of species, a key to species identification, and a compendium of their main morphometrics and distribution data
Matrices over finite fields of odd characteristic as sums of diagonalizable and square-zero matrices
No full textLet F be a finite field of odd characteristic. When |F| >= 5 , we prove that every matrix A admits a decomposition into D+M , where D is diagonalizable and M-2=0. For F=F-3, we show that such a decomposition is possible for non-derogatory matrices of order at least 5, and more generally, for matrices whose first invariant factor is not a non-zero trace irreducible polynomial of degree 3; we also establish that matrices consisting of direct sums of companion matrices, all of them associated to the same irreducible polynomial of non-zero trace and degree 3 over F-3, never admit such a decomposition. These results completely settle the question posed by Breaz (2018) [3] asking if it is true that, for big enough positive integers n >= 3, all matrices A over a field of odd cardinality q admit decompositions of the form E+M with E-q = E and M-2 = 0 : specifically, the answer is yes for q >= 5 , but however there are counterexamples for q=3 and each order n=3k, whenever k >= 1
Multigene phylogeny of root-knot nematodes and molecular characterization of Meloidogyne nataliei Golden, Rose & Bird, 1981 (Nematoda:Tylenchida)
No full textThe root-knot nematodes of the genus Meloidogyne are highly adapted, obligate plant parasites, consisting of nearly one hundred valid species, and are considered the most economically important group of plant-parasitic nematodes. Six Meloidogyne species: M. arenaria, M. hapla, M. incognita, M. microtyla, M. naasi and M. nataliei were previously reported in Michigan, USA. For this study, Meloidogyne nataliei was isolated from the grapevine Vitis labrusca from the type locality in Michigan, USA, and was characterized using isozyme analysis and ribosomal and mitochondria! gene sequences. No malate dehydrogenase activity was detected using macerate of one, five, six, seven or ten females of M. nataliei per well. However, one strong band (EST= 51; Rm: 27.4) of esterase activity was detected when using homogenates of ten egg-laying females per well. Phylogenetic analyses of sequences of the partial 18S ribosomal RNA, D2-D3 of 285 rRNA, internal transcribed spacer of rRNA, mitochondrial cytochrome oxidase subunit I genes and the cytochrome oxidase subunit II-165 rRNA intergeneric fragment from fifty-five valid Meloidogyne species and M. nataliei were conducted using Bayesian inference and maximum likelihood methods. From these results, we infer 11 distinct clades among studied species, with M. nataliei and M. indica composing a basal lineage. Seventy five percent of these species belong to seven clades within the Meloidogyne superclade. Characterization of these clades is provided and evolutionary trends within the root-knot nematodes are discussed
Implementing virtual reality in the healthcare sector
No full textThis chapter will concentrate on the advantages that VR can offer to the Healthcare Sector. After a brief introduction, the second section will present an analysis of the areas where VR techniques can be successfully applied. Next section will describe some existing VR applications in healthcare. The development of a VR surgery simulator, with all the aspects that make this process challenging, will be presented on the following section. An analysis of the difficulties specific to healthcare environments while dealing with the design and development of VR applications will be covered in the next section. The last section will be devoted to conclusions and future perspectives of VR in the Healthcare Sector. © 2011, IGI Global
Improving the Teaching of Hypothesis Testing Using a Divide-and-Conquer Strategy and Content Exposure Control in a Gamified Environment
No full textHypothesis testing has been pointed out as one of the statistical topics in which students present more misconceptions. In this article, an approach based on the divide-and-conquer methodology is proposed to facilitate its learning. The proposed strategy is designed to sequentially explain and evaluate the different concepts involved in hypothesis testing, ensuring that a new concept is not presented until the previous one has been fully assimilated. The proposed approach, which contains several gamification elements (i.e., points or a leader-board), is implemented into an application via a modern game engine. The usefulness of the proposed approach was assessed in an experiment in which 89 first-year students enrolled in the Statistics course within the Industrial Engineering degree participated. Based on the results of a test aimed at evaluating the acquired knowledge, it was observed that students who used the developed application based on the proposed approach obtained statistically significant higher scores than those that attended a traditional class (p-value < 0.001), regardless of whether they used the learning tool before or after the traditional class. In addition, the responses provided by the students who participated in the study to a test of satisfaction showed their high satisfaction with the application and their interest in the promotion of these tools. However, despite the good results, they also considered that these learning tools should be considered as a complement to the master class rather than a replacement