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ABSTRACTIn the Staged Progression (SP) epidemic models, infected individuals are classified into a suitable number of states. The goal of these models is to describe as closely as possible the effect of differences in infectiousness exhibited by individuals going through the different stages. The main objective of this work is to study, from the methodological point of view, the behaviour of solutions of the discrete time SP models without reinfection and with a general incidence function. Besides calculating [Formula: see text], we find bounds for the epidemic final size, characterize the asymptotic behaviour of the infected classes, give results about the final monotonicity of the infected classes, and obtain results regarding the initial dynamics of the prevalence of the disease. Moreover, we incorporate into the model the probability distribution of the number of contacts in order to make the model amenable to study its effect in the dynamics of the disease.

Abstract The main aim of the work is to present a general class of two time scales discrete-time epidemic models. In the proposed framework the disease dynamics is considered to act on a slower time scale than a second different process that could represent movements between spatial locations, changes of individual activities or behaviors, or others. To include a sufficiently general disease model, we first build up from first principles a discrete-time susceptible–exposed–infectious–recovered–susceptible (SEIRS) model and characterize the eradication or endemicity of the disease with the help of its basic reproduction number R 0 $\mathcal{R}_{0}$ . Then, we propose a general full model that includes sequentially the two processes at different time scales and proceed to its analysis through a reduced model. The basic reproduction number R ‾ 0 $\overline{\mathcal{R}}_{0}$ of the reduced system gives a good approximation of R 0 $\mathcal{R}_{0}$ of the full model since it serves at analyzing its asymptotic behavior. As an illustration of the proposed general framework, it is shown that there exist conditions under which a locally endemic disease, considering isolated patches in a metapopulation, can be eradicated globally by establishing the appropriate movements between patches.

Ensuring the effective management of every rhinoceros population is crucial for securing a future for the species, especially considering the escalating global threat of poaching and the challenges faced in captive breeding programs for this endangered species. Steroid hormones play pivotal roles in regulating diverse biological processes, making fecal hormonal determinations a valuable non-invasive tool for monitoring adrenal and gonadal endocrinologies and assessing reproductive status, particularly in endangered species. The purpose of this study was to develop a statistical model for predicting the sex of white rhinoceroses using hormonal determinations obtained from a single fecal sample. To achieve this, 562 fecal samples from 15 individuals of the Ceratotherium simum species were collected, and enzyme immunoassays were conducted to determine the concentrations of fecal cortisol, progesterone, estrone, and testosterone metabolites. The biological validation of the method provided an impressive accuracy rate of nearly 80% in predicting the sex of hypothetically unknown white rhinoceroses. Implementing this statistical model for sex identification in white rhinoceroses would yield significant benefits, including a better understanding of the structure and dynamics of wild populations. Additionally, it would enhance conservation management efforts aimed at protecting this endangered species. By utilizing this innovative approach, we can contribute to the preservation and long-term survival of white rhinoceros populations.

Abstract Steroidal hormone interaction in pregnancy is crucial for adequate fetal evolution and preparation for childbirth and extrauterine life. Estrone sulphate, estriol, progesterone and cortisol play important roles in the initiation of labour mechanism at the start of contractions and cervical effacement. However, their interaction remains uncertain. Although several studies regarding the hormonal mechanism of labour have been reported, the prediction of date of birth remains a challenge. In this study, we present for the first time machine learning algorithms for the prediction of whether spontaneous labour will occur from week 37 onwards. Estrone sulphate, estriol, progesterone and cortisol were analysed in saliva samples collected from 106 pregnant women since week 34 by enzyme-immunoassay (EIA) techniques. We compared a random forest model with a traditional logistic regression over a dataset constructed with the values observed of these measures. We observed that the results, evaluated in terms of accuracy and area under the curve (AUC) metrics, are sensibly better in the random forest model. For this reason, we consider that machine learning methods contribute in an important way to the obstetric practice.

Abstract Background The interaction of hormonal factors are crucial for good foetal development. During the second trimester of gestation, most of the main physiological processes of foetal development occur. Therefore, the aim of this study was to determine the variations in the physiological levels of cortisol, estriol, estrone sulphate, and progesterone during the second trimester (weeks 12–26) in order to establish normal ranges that can serve as indicators of foetal well-being and good functioning of the foetal-placental unit. Methods Saliva samples from 106 pregnant women were collected weekly (from week 12 to week 26 of gestation), and hormonal measurements were assayed by an enzyme immunoassay. The technique used for hormone measurements was highly sensitive and served as a non-invasive method for sample collection. Results The results revealed a statistically significant (p

La financiación de la investigación es una herramienta de los gobiernos para promover cambios en las universidades. Los gobiernos han intentado guiar «a distancia» a las universidades cambiando las formas de financiación y potenciando la evaluación. El artículo analiza un instrumento de financiación de centros universitarios de I+D de la Xunta de Galicia, su fundamentación lógica y los mecanismos a través de los cuales se promueve el cambio institucional. Asimismo, analiza también cómo los resultados perseguidos se ven condicionados por los instrumentos existentes y por las restricciones institucionales. El estudio confirma que el avance en los objetivos de un instrumento puede verse limitado port otros, en ausencia de coherencia de la cartera de instrumentos; y también que las limitaciones institucionales, derivadas del modelo de gobernanza universitaria, pueden convertirse en obstáculos para la transformación de las estructuras de investigación. Se concluye que los programas de financiación competitiva de centros de I+D pueden tener una capacidad transformadora, en ocasiones a través de cambios no esperados por los decisores públicos; pero que la influencia del modelo de gobernanza, del resto de instrumentos y el comportamiento de los actores condiciona la intensidad y la dirección de los cambios.

Abstract In this work we present a reduction result for discrete-time systems with two time scales. In order to be valid, previous results in the field require some strong hypotheses that are difficult to check in practical applications. Roughly speaking, the iterates of a map as well as their differentials must converge uniformly on compact sets. Here, we eliminate the hypothesis of uniform convergence of the differentials at no significant cost in the conclusions of the result. This new result is then used to extend to non-linear cases the reduction of some population discrete models involving processes acting at different time scales. In practical cases, some processes that occur at a fast time scale are often only measured at slow time intervals, notably mortality. For a general class of linear models that include such a kind of processes, it has been shown that a more realistic approach requires the re-scaling of those processes to be considered at the fast time scale. We develop the same type of re-scaling in some non-linear models and prove the corresponding reduction results. We also provide an application to a particular model of a structured population in a two-patch environment.

Hormone patterns tailor cell fate decisions during plant organ formation. Among them, auxins and cytokinins are critical phytohormones during early development. Nitric oxide (NO) modulates root architecture by the control of auxin spatial patterns. However, NO involvement during the coordination of shoot organogenesis remains unclear. Here, we explore the effect of NO during shoot development by using a phenotypic, cellular, and genetic analysis in Arabidopsis thaliana and get new insights into the characterization of NO-mediated leaf-related phenotypes. NO homeostasis mutants are impaired in several shoot architectural parameters, including phyllotactic patterns, inflorescence stem elongation, silique production, leaf number, and margin. Auxin distribution is a key feature for tissue differentiation and need to be controlled at different levels (i.e., synthesis, transport, and degradation mechanisms). The phenotypes resulting from the introduction of the cue1 mutation in the axr1 auxin resistant and pin1 backgrounds exacerbate the relationship between NO and auxins. Using the auxin reporter DR5:GUS, we observed an increase in auxin maxima under NO-deficient mutant backgrounds and NO scavenging, pointing to NO-ASSOCIATED 1 (NOA1) as the main player related to NO production in this process. Furthermore, polar auxin transport is mainly regulated by PIN-FORMED 1 (PIN1), which controls the flow along leaf margin and venations. Analysis of PIN1 protein levels shows that NO controls its accumulation during leaf development, impacting the auxin mediated mechanism of leaf building. With these findings, we also provide evidence for the NO opposite effects to determine root and shoot architecture, in terms of PIN1 accumulation under NO overproduction.

In this work we develop approximate aggregation techniques in the context of slow-fast linear population models governed by stochastic differential equations and apply the results to the treatment of populations with spatial heterogeneity. Approximate aggregation techniques allow one to transform a complex system involving many coupled variables and in which there are processes with different time scales, by a simpler reduced model with a fewer number of ‘global’ variables, in such a way that the dynamics of the former can be approximated by that of the latter. In our model we contemplate a linear fast deterministic process together with a linear slow process in which the parameters are affected by additive noise, and give conditions for the solutions corresponding to positive initial conditions to remain positive for all times. By letting the fast process reach equilibrium we build a reduced system with a lesser number of variables, and provide results relating the asymptotic behaviour of the first- and second-order moments of the population vector for the original and the reduced system. The general technique is illustrated by analysing a multiregional stochastic system in which dispersal is deterministic and the rate growth of the populations in each patch is affected by additive noise.

The cue1 nitric oxide (NO) overproducer mutants are impaired in a plastid phosphoenolpyruvate/phosphate translocator, mainly expressed in Arabidopsis thaliana roots. cue1 mutants present an increased content of arginine, a precursor of NO in oxidative synthesis processes. However, the pathways of plant NO biosynthesis and signaling have not yet been fully characterized, and the role of CUE1 in these processes is not clear. Here, in an attempt to advance our knowledge regarding NO homeostasis, we performed a deep characterization of the NO production of four different cue1 alleles (cue1-1, cue1-5, cue1-6 and nox1) during seed germination, primary root elongation, and salt stress resistance. Furthermore, we analyzed the production of NO in different carbon sources to improve our understanding of the interplay between carbon metabolism and NO homeostasis. After in vivo NO imaging and spectrofluorometric quantification of the endogenous NO levels of cue1 mutants, we demonstrate that CUE1 does not directly contribute to the rapid NO synthesis during seed imbibition. Although cue1 mutants do not overproduce NO during germination and early plant development, they are able to accumulate NO after the seedling is completely established. Thus, CUE1 regulates NO homeostasis during post-germinative growth to modulate root development in response to carbon metabolism, as different sugars modify root elongation and meristem organization in cue1 mutants. Therefore, cue1 mutants are a useful tool to study the physiological effects of NO in post-germinative growth.

Many experiments require simultaneously testing many hypotheses. This is particularly relevant in the context of DNA microarray experiments, where it is common to analyze many genes to determine which of them are differentially expressed under two conditions. Another important problem in this context is how to model the dependence at the level of gene expression. In this paper, we propose a Bayesian procedure for simultaneously testing multiple hypotheses, modeling the dependence through copula functions, where all available information, both objective and subjective, can be used. The approach has the advantage that it can be used with different dependency structures. Simulated data analysis was performed to examine the performance of the proposed approach. The results show that our procedure captures the dependence appropriately classifying adequately a high percentage of true and false null hypotheses when choosing a prior distribution beta skewed to the right for the initial probability of each null hypothesis, resulting in a very powerful procedure. The procedure is also illustrated with real data.

Este artículo explica comparativamente las políticas de ciencia, tecnología e innovaciónde cinco comunidades autónomas, desde mediados de los años ochenta hasta principiosde la presente década. Sobre la base de cinco estudios de caso, este trabajo describe,en primer lugar, la orientación académica o empresarial de dichas políticas atendiendoa los objetivos de la inversión presupuestaria, el destino de los recursos y las opcionesinstitucionales. A continuación, se analizan los factores explicativos más influyentes, parallegar a una serie de conclusiones sobre las circunstancias bajo las cuales los gobiernosregionales pueden poner en práctica políticas con mayor énfasis en una u otra orientación.A pesar de la influencia de los factores estructurales, en especial en la configuracióninicial de las preferencias políticas, el análisis pone de manifiesto la importancia de losintereses movilizados y concentrados en la región, constatándose que los cambios de orientaciónson particularmente difíciles cuando estos intereses participan en la administraciónde las políticas. La coyuntura presupuestaria se revela como una de las variables intervinientesque más condicionan la relación entre las preferencias políticas y la orientaciónresultante, en el contexto de la presión de los intereses. Las preferencias a favor de unareorientación de la política pueden llevarse a cabo con arreglos institucionales adecuadosque trasciendan departamentos concretos, sobre todo si se acompañan con incrementospresupuestarios significativos.

En este artículo se analizan las transformaciones en las políticas europeas de investigacióny desarrollo tecnológico y se exploran cuáles son los factores que explican esta evolución.Se argumenta que las ideas, por sí solas, no pueden dar cuenta de la dinámica de laspolíticas de IDT. Las políticas crean su propio juego de intereses y la naturaleza distributivade este tipo de intervenciones ha contribuido a que los cambios, notables enel discurso, hayan sido menos relevantes en las políticas. Dos variables aparecen comofundamentales a la hora de dar cuenta del cambio y la estabilidad: la existencia de actorescon los suficientes recursos como para formar coaliciones de apoyo de determinados enfoquese instrumentos, y el grado en que la configuración de las reglas de juego, que sonlas que en definitiva dotan de fuerza institucional a las políticas, lleven a la estabilidado permitan las innovaciones.

Over the last two decades, the Spanish higher education and research sector has undergone profound changes, but little is known about the implementation of recent reforms and how university actors responded to policy change and institutional pressures within a changing resource environment. Drawing on the insights from institutional and resource-dependence theory, we show how Spanish public universities have coped and implemented their human resources policy over the past 15 years and whether individual universities converged in their employment behaviour. The aggregate evolution of university employment trends reveals adaptation to the institutional normative pressures and financial constraints. Our results also show that some universities are more responsive to changes in the resource environment than others, and that compliance is not the only strategic response. In so doing, we aim to contribute to existing research on strategic behaviour of actors and coalitions facing policy change, and to the construction of analytical bridges between environmental changes (institutional and economic) and organisational dynamics underlying policy implementation.

En este artículo se describe y analiza la evolución que ha seguido la política regional de ciencia, tecnología e innovación de Andalucía desde la primera mitad de los 80, a partir de la consideración de diversas variables tales como los modelos e ideas, los intereses, las preferencias políticas y el contexto socioeconómico e institucional. Andalucía fue una de las primeras Comunidades Autónomas que emprendió una política regional de ciencia, tecnología e innovación. En esta comunidad se ha desarrollado un modelo de política caracterizado por la separación de las esferas de la política científica y de la política tecnológica con un predominio de la primera sobre la segunda. Se argumenta que el factor decisivo que explica tanto la adopción en Andalucía de un modelo de política regional de I+D de orientación académica, como su estabilidad a lo largo de los años, ha sido la fuerza que han tenido en esta región los intereses universitarios en el juego político andaluz.

El artículo trata sobre la utilización de la prospectiva tecnológica en el diseño y desarrollo de las políticas científicas y tecnológicas. Primero, hace una aproximación conceptual en la que se presenta una doble visión de la prospectiva como fuente de información para los decisores públicos y como proceso de coordinación en los sistemas nacionales de innovación. Después se repasa el uso de la prospectiva en otros países, explicando cómo y en qué contexto surgen. Por último, se analiza la situación española y sus tendencias y se plantean algunas reflexiones sobre la utilización de la prospectiva como instrumento de las políticas públicas.

Understanding how institutional incentives and mechanisms for assigning recognition shape access to a permanent job is important. This study, based on data from questionnaire survey responses and publications of 1,257 university science, biomedical and engineering faculty in Spain, attempts to understand the timing of getting a permanent position and the relevant factors that account for this transition, in the context of dilemmas between mobility and permanence faced by organizations. Using event history analysis, the paper looks at the time to promotion and the effects of some relevant covariates associated to academic performance, social embeddedness and mobility. We find that research productivity contributes to career acceleration, but that other variables are also significantly associated to a faster transition. Factors associated to the social elements of academic life also play a role in reducing the time from PhD graduation to tenure. However, mobility significantly increases the duration of the non-tenure stage. In contrast with previous findings, the role of sex is minor. The variations in the length of time to promotion across different scientific domains is confirmed, with faster career advancement for those in the Engineering and Technological Sciences compared with academics in the Biological and Biomedical Sciences. Results show clear effects of seniority, and rewards to loyalty, in addition to some measurements of performance and quality of the university granting the PhD, as key elements speeding up career advancement. Findings suggest the existence of a system based on granting early permanent jobs to those that combine social embeddedness and team integration with some good credentials regarding past and potential future performance, rather than high levels of mobility.

Este artículo describe la emergencia y orientación de las políticas de I+D e innovación en Cataluña. Se analizan cuáles son los factores más influyentes en la orientación de estas políticas y, en definitiva, en las opciones políticas que se toman. La política de ciencia y tecnología desarrollada por el gobierno regional catalán desde principios de los años ochenta ha sido una política en la que, a pesar de las preferencias manifestadas en el discurso político, ha predominado un modelo de política académico sobre el de orientación empresarial. Asimismo, en términos organizativos e institucionales, en la Administración autonómica, la política científica ha estado separada y diferenciada de la política tecnológica a pesar del diseño inicial de instituciones interdepartamentales. La principal razón de que la política de I+D catalana no siguiera un modelo más industrial, ligado al mundo empresarial, fue la presión que ejercieron las universidades catalanas para que, tanto el diseño institucional como el contenido de la política se adaptara a sus necesidades. La trayectoria académica previa de los gestores también contribuyó a la reorientación de las preferencias políticas. A pesar de la importancia de las empresas catalanas en la I+D, éstas no se movilizaron ni presionaron a los gobiernos suficientemente. Analíticamente, este caso ilustra cómo la sola creación política de instituciones no garantiza la realización de las preferencias políticas. También pone de manifiesto cómo el horizonte temporal de la toma de decisiones gubernamental tiene un efecto en las expectativas de los actores, que desarrollan procesos de aprendizaje a partir de las experiencias en arenas políticas similares a otros niveles. Por último, destaca la importancia del poder en las instituciones de gestión en este tipo de política distributiva.

Iguanodon bernissartensis is the most frequently and widely cited styracosternan ornithopod in Western Europe during the Early Cretaceous, although some of these assignments likely need to be revised to establish the true distribution of the taxon. Here, we describe a new specimen of I. bernissartensis from the upper Barremian of the Iberian Peninsula. Based on the unique combination of shared characters, the new specimen from the Arcillas de Morella Formation at Morella locality (Castellón, Spain) can be confidently referred to Iguanodon bernissartensis. These characters include parallel-sided anterior and posterior margins of the dorsal and the caudal neural spines as well as the presence of a ventral keel in the posterior dorsal centra and a broad ventral sulcus in the midline of the central surface of the most posterior sacral vertebrae. This new evidence of Iguanodon bernissartensis reinforces the knowledge about styracosternan ornithopods as the most frequently recorded dinosaur group in the Arcillas de Morella Formation.

Introduction: This scoping review explores the effectiveness of IL-1 pathway inhibitors in managing PSTPIP1-associated inflammatory diseases (PAID). These diseases are marked by abnormal IL-1 pathway activation due to genetic mutations. Methods: Our methodology adhered to a pre-published protocol and involved a thorough search of MEDLINE and EMBASE databases up to February 2022, following the Joanna Briggs Institute Reviewer's Manual and the PRISMA Extension for Scoping Reviews. The review included studies reporting on IL-1 pathway inhibitor use in PAID patients. Results: From an initial pool of 5,225 articles, 36 studies involving 43 patients were selected. The studies predominantly used observational designs and exhibited diversity in patient demographics, treatment approaches, and outcomes. Anakinra and canakinumab demonstrated promise in treating sterile pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) and PSTPIP1-associated myeloidrelated-proteinemia inflammatory (PAMI) syndromes, with scant data on other syndromes. Notably, there was a paucity of information on the adverse effects of these treatments, necessitating cautious interpretation of their safety profile. Conclusion: Current evidence on IL-1 pathway inhibitors for PAID is primarily from observational studies and remains limited. Rigorous research with larger patient cohorts is imperative for more definitive conclusions. Collaborative efforts among specialized research centers and international health initiatives are key to advancing this field. [ABSTRACT FROM AUTHOR]

Background: the prognosis of peri-implant surgery can be affected by poor decontamination of the implant surface, which could be improved with the use of titanium brushes. The objectives of this systematic review were to evaluate the effectiveness of titanium brushes in the decontamination of the implant surface in terms of plaque index, probing depth, bleeding on probing and bone loss/gain; as well as its effectiveness according to the type of peri-implant bone defect. Methods: an electronic search was carried out in the PubMed, Scopus, Cochrane and Embase databases, as well as a manual search. The search strategy included four keywords: “Peri-implantitis”, “Periimplantitis”, “Implant Surface Decontamination” and “Titanium Brush”. Randomized controlled studies published in the last 10 years were included and systematic reviews, in vitro studies and animal studies were excluded. Results: 142 references were found, from which only four articles met the inclusion criteria. All of the studies included in the present review reported beneficial results in terms of probing depth, gingival index and radiographic bone loss and gain after implant surface decontamination adjuvated by titanium brushes. Conclusions: titanium rotary brushes show improvements in the evolution and prognosis of peri-implant surgery, although more long-term studies are needed to draw more solid conclusions.