Analysis of a chemo-repulsion model with nonlinear production: The continuous problem and unconditionally energy stable fully discrete schemes

We consider the following repulsive-productive chemotaxis model: Let $p\in (1,2)$, find $u \geq 0$, the cell density, and $v \geq 0$, the chemical concentration, satisfying \begin{equation}\label{C5:Am} \left\{ \begin{array} [c]{lll} \partial_t u - \Delta u - \nabla\cdot (u\nabla v)=0 \ \ \mbox{in}\ \Omega,\ t>0,\\ \partial_t v - \Delta v + v = u^p \ \ \mbox{in}\ \Omega,\ t>0, \end{array} \right. \end{equation} in a bounded domain $\Omega\subseteq \mathbb{R}^d$, $d=2,3$. By using a regularization technique, we prove the existence of solutions of this problem. Moreover, we propose three fully discrete Finite Element (FE) nonlinear approximations, where the first one is defined in the variables $(u,v)$, and the second and third ones by introducing ${\boldsymbol\sigma}=\nabla v$ as an auxiliary variable. We prove some unconditional properties such as mass-conservation, energy-stability and solvability of the schemes. Finally, we compare the behavior of the schemes throughout several numerical simulations and give some conclusions.Comment: arXiv admin note: substantial text overlap with arXiv:1807.0111

Potentiation by cyclooxygenase inhibitors of the release of catecholamines from the rabbit carotid body and its reversal by prostaglandin E2

Producción CientíficaSalicylates, at the high therapeutic doses used in the treatment of rheumatoid arthritis, produce an increase in ventilation and augment the carotid body reactivity to hypoxic stimulus, leading to an exaggerated hyperventilation during hypoxia. These effects had been related to the action of salicylates as uncouplers of oxidative phosphorylation. In the present study, carried out in an in vitro preparation of the rabbit carotid body, we show that acetylsalicylic acid and indomethacin, two anti-inflammatory drugs that are also powerful inhibitors of cyclooxygenase, the prostaglandinsynthetizing enzyme, produce an increase in the [3H]catecholamine release evoked by low oxygen stimulation. The drugs did not affect basal normoxic release, a finding that suggests that at the concentration used these anti-inflammatory agents do not have uncoupling actions, and that their effects on hypoxic-induced release of [3H]catecholamines is mediated by their specific action as cyclooxygenase inhibitors. In agreement with this suggestion we found that prostaglandin E~ completely prevented the effects of both anti-inflammatory agents. In addition, our data indicate that endogenously synt hetized prostaglandins are powerful modulators of chemoreceptor cell function

Assessment of Virgin Olive Oil Adulteration by a Rapid Luminescent Method

The adulteration of virgin olive oil with hazelnut oil is a common fraud in the food industry, which makes mandatory the development of accurate methods to guarantee the authenticity and traceability of virgin olive oil. In this work, we demonstrate the potential of a rapid luminescent method to characterize edible oils and to detect adulterations among them. A regression model based on five luminescent frequencies related to minor oil components was designed and validated, providing excellent performance for the detection of virgin olive oil adulteration

Differential stimulus coupling to dopamine and norepinephrine stores in rabbit carotid body type I cells

Recent studies suggest that preneural type I (glomus) cells in the arterial chemoreceptor tissue of the carotid body act as primary transducer elements which respond to natural stimuli (low 02, pH or increased CO2) by releasing chemical transmitter agents capable of exciting the closely apposed afferent nerve terminals. These type I cells contain multiple putative transmitters, but the identity of the natural excitatory agents remains an unresolved problem in carotid body physiology. Characterization of putative transmitter involvement in the response to natural and pharmacological stimuli has therefore become fundamental to further understanding of chemotransmission in this organ. The present study demonstrates that a natural stimulus (hypoxia) evokes the release of dopamine (DA) and norepinephrine (NE) in approximate proportion to their unequal stores in rabbit carotid body (DA release/NE release = 8.2). In contrast, nicotine (100/~M), a cholinornimetic agent thought to act on the nicotinic receptors present on the type I cells, evokes the preferential release of NE (DA release/NE release = 0.17). These findings suggest that distinct mechanisms are involved in a differential mobilization of these two cateeholamines from the rabbit carotid body

An Overview on the Application of Chemometrics Tools in Food Authenticity and Traceability

The use of advanced chemometrics tools in food authenticity research is crucial for managing the huge amount of data that is generated by applying state-of-the-art analytical methods such as chromatographic, spectroscopic, and non-targeted fingerprinting approaches. Thus, this review article provides description, classification, and comparison of the most important statistical techniques that are commonly employed in food authentication and traceability, including methods for exploratory data analysis, discrimination, and classification, as well as for regression and prediction. This literature revision is not intended to be exhaustive, but rather to provide a general overview to non-expert readers in the use of chemometrics in food science. Overall, the available literature suggests that the selection of the most appropriate statistical technique is dependent on the characteristics of the data matrix, but combining complementary tools is usually needed for properly handling data complexity. In that way, chemometrics has become a powerful ally in facilitating the detection of frauds and ensuring the authenticity and traceability of foods.This research has received funding from the Junta de Andalucía within the framework of the Programa Operativo FEDER 2014-2020 (UHU-202063). R.G.-D. is recipient of a Miguel Servet fellowship (CP21/00120) funded by the Instituto de Salud Carlos III

A canonical form for the continuous piecewise polynomial functions

We present in this paper a canonical form for the elements in the ring of continuous piecewise polynomial functions. This new representation is based on the use of a particular class of functions fCi(P) : P 2 Q[x]; i = 0; : : : ; deg(P)g de ned by Ci(P)(x) = 0 if x P(x) if x where is the i-th real root of the polynomial P. These functions will allow us to represent and manipulate easily every continuous piecewise polynomial function through the use of the corresponding canonical form. It will be also shown how to produce a \rational" representation of each function Ci(P) allowing its evaluation by performing only operations in Q and avoiding the use of any real algebraic number. Keywords: Continuous piecewise polynomial functions; Pierce-Birkho conjecture; Canonical form for func- tions; Conversion algorithms

Potential of Ultraviolet-Visible Spectroscopy for the Differentiation of Spanish Vinegars According to the Geographical Origin and the Prediction of Their Functional Properties

High-quality wine vinegars with unique organoleptic characteristics are produced in southern Spain under three Protected Designations of Origin (PDO), namely “Jerez”, “Condado de Huelva” and “Montilla-Moriles”. To guarantee their authenticity and avoid frauds, robust and low-cost analytical methodologies are needed for the quality control and traceability of vinegars. In this study, we propose the use of ultraviolet-visible spectroscopy in combination with multivariate statistical tools to discriminate Spanish wine vinegars according to their geographical origin, as well as to predict their physicochemical and functional properties. Linear discriminant analysis provided a clear clustering of vinegar samples according to the PDO with excellent classification performance (98.6%). Furthermore, partial least squares regression analysis demonstrated that spectral data can serve as accurate predictors of the total phenolic content and antioxidant activity of vinegars. Accordingly, UV-Vis spectroscopy stands out as a suitable analytical tool for simple and rapid authentication and traceability of vinegars

Technologies as a support resource for people with disabilities: a systematic review

The increasing use of Information and Communication Technologies (ICT) has brought advances in interventions for people with disabilities. The aim of this study was to review the scientific literature of the last ten years regarding technologies as tools for improving the quality of life of people with disabilities. To this end, PRISMA methodology was used, performing a search in two different databases: Scopus and Web of Science (WoS), obtaining a final sample of 21 studies. To evaluate the risk of bias, the ROBIS tool was used, and the VOSviewer software was employed to carry out a keyword co-occurrence analysis. The main result to emerge was that the scientific literature is increasing, and that the most studied skills are those related to writing and reading. Most of the participants have intellectual disability or autism spectrum disorder move this sentence up. The scientific literature is still scarce; therefore, further research is necessary in this field, since the inclusion of ICT in the day-to-day, both in the teaching-learning process and in activities of daily living, offers new opportunities to people with disability

Features of non-kinship foster care children with birth family contact in Andalusia

The aim of the presentation is to describe the personal features of non-kinship foster care children who have visits with their birth family in Málaga, Granada and Jaén (provinces of Andalusia, Spain). This study was funded by the research project Application of a psychoeducational intervention program to improve visits between foster children and their biological families (Reference EDU2016 77094-P). SPSS v.21.0 was used to carry out the descriptive and frequency analysis of socio-demographic information collected by the Child File Summary Form designed for this study. There are 212 non-kinship foster care children who have visits with their birth family. Their mean age is 8.09 years old (SD= 4.73). The more frequent types of foster care are both long-term and short-term placement (30.7%, respectively), followed by specialized long-term foster care (20.3%), urgency placement (10.8%) and specialized short-term foster care (7.5%). The period of time they have been into the Child Protection System is on average 4.08 years (SD= 3.88) and into the current placement is on average 2.53 (SD= 2.95). Thus, 44.8% of foster children were in residential care and 30.2% were in previous foster care. The latter could have been with the current foster care family. Also, 41.0% of foster children were placed at least with one sibling. It is important to know the features of foster children in order to apply the main principle of “the best interests of the child” to the whole decision-making process about the child’s protection and welfare. In our project, these decisions concern foster care placement and birth family contact to maintain and strengthen family affective bonds and child’s identity formation. Our findings contribute to develop: (a) initiatives to improve children’s well-being; (b) support and social resources required by families; and (c) socio-educative tools for the social workers.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Hollow-Fiber Liquid-Phase Micro-Extraction Method for the Simultaneous Derivatization, Extraction, and Pre-concentration of Organotin Compounds from Packed Fruit Juices

Organotin compounds are widely employed as pesticides and fungicides in agriculture and as stabilizers for the industrial manufacture of polyvinyl chloride and other polymers. Accordingly, these endocrine disruptors can be found in a variety of foods and beverages. In the present study, we describe the optimization of a hollow-fiber liquid-phase micro-extraction approach for the simultaneous derivatization, extraction, and pre-concentration of butyltin species from commercial fruit juices with the aim of investigating their migration from the packaging. The best extraction efficiencies were achieved by using hexane as the acceptor solvent and a polypropylene fiber length of 2 cm, whereas the agitation speed, extraction temperature, and total extraction time were set at 1100 rpm, 25 ºC, and 10 min, respectively. Using these optimal conditions, the method was satisfactorily validated in terms of linearity (5–1000 µg L−1), limits of detection (0.8–1.8 µg L−1), recovery (80.5–92.1%), intraday precision (10.2–13.1%), inter-day precision (11.0–15.5%), matrix effect (83.2–91.8%), accuracy (85.2–95.2%), specificity, and carryover. The application of this technique to commercial samples obtained from a local market demonstrated that levels of organotin species in packed fruit juices are negligible, in agreement with the limits established by the European Food Safety Authority (0.14 mg of total organotin compounds per kg of food).Open Access funding provided by Universidad de Huelva/ CBUA thanks to the CRUE-CSIC agreement with Springer Natur