Constitutions change in different ways, and some constitutions – such as the Chilean Constitution – change often. The significant changes to the Chilean Constitution have been frequent and fast, and they have accompanied the failed constitution-making processes of the previous years. Examples include crucial sub-constitutional statutes such as the electoral system regulation and same-sex marriage, political practices challenging the power of the president in the law-making process, constitutional rules such as term limits for legislators, judicial practices such as the enforcement of social rights and the amendment procedures of the Constitution itself. Despite the successful attempts at reforming the Constitution and the failed attempts at replacing it, Chileans are still trying to replace the constitutional document. However, the constitutional framework has become unstable, making it harder to agree on what exactly is wrong with it. This article seeks to open a conversation in the constitutional literature. It argues that constitutions can become moving targets and uses the Chilean case to show the need to theorize more about the moving target problem.

We carry out direct numerical simulations of flow in a plane open channel at friction Reynolds number up to ${{Re}}_{\tau } \approx 6000$. We find solid evidence for the presence of universal large-scale organization in the outer layer, with eddies that are larger and stronger than in the closed channel flow. As a result, velocity fluctuations are found to be stronger than in closed channels, throughout the depth. The inner-layer peak of the streamwise velocity variance is observed to grow logarithmically, as in Townsend's attached-eddy model (Townsend, The Structure of Turbulent Shear Flow, 2nd edn, Cambridge University Press, 1976), but saturation of the growth cannot be discarded based on the present data. Although we do not observe a clear outer peak of the streamwise velocity variance, we present substantial evidence that such a peak should emerge at a Reynolds number barely higher than achieved herein. The most striking feature of the flow is the presence of an extended logarithmic layer, with associated Kármán constant asymptoting to $k \approx 0.375$, in line with observations made in shear-free Couette–Poiseuille flow (Coleman et al., Flow Turbul. Combust., vol. 99, issue 3, 2017, pp. 553–564). The virtual absence of a wake region and of corrective terms to the log law in the present flow leads us to conclude that deviations from the log law observed in internal flows are likely due to the effects of the opposing walls, rather than the presence of a driving pressure gradient.

Discoveries of transient liquid water in the Martian polar caps and the presence of liquid lakes and subsurface oceans in icy satellites have increased the interest of scientists in the capabilities of terrestrial extremophiles to grow and remain metabolically active in these extreme environments. The principal goal of this research is to understand the metabolic capacity of the anaerobic psychrophile, Desulfotalea psychrophila, cultured at subfreezing temperatures in media containing various concentrations of sulphate minerals. In this regard, our experiments focused on the detection of D. psychrophila survival and active metabolism, employing a biochamber that can recreate Martian temperatures. Using standard bacteriological methods for determining growth, combined with molecular and enzymatic determination of sulphate reduction, we have found that D. psychrophila is capable to carry out biological processes at temperatures down to −5°C, at concentrations that range from 0.35 to 18 wt% of MgSO4, 0.1 wt% of CaSO4 and 10 to 14 wt% of FeSO4 in which the highest sulphate concentration gradually returned the biosynthetic rate to basal limits, and the lowest temperature decreased bacterial cell division. These chemical salts, whose ions are classified as chaotropes, are known to act by maintaining water molecules in liquid state at subfreezing temperatures and by altering the stability of cellular components. This ‘chaotropic effect’ could potentially benefit the microbial metabolic activity up to a concentration in which cellular viability is jeopardized. Consequently, our hypothesis is directed towards the detection of metabolic activity as an indirect measurement of the potential influence of these ions in the flexibility/functionality of biological structures that at cold temperatures are highly rigid, compact and partially/non-functional due to water freezing. Studies of this type of microorganism are critical considering the possibility of survival and colonization of psychrophilic sulphate reducers in other planets and icy satellites.

The paper deals with the existence of positive solutions with prescribed $L^2$ norm for the Schrödinger equation

$$-\Delta u+\lambda u+V(x)u=|u|^{p-2}u,\quad u\in H^1_0(\Omega),\quad\int_\Omega u^2{\rm d}\,x=\rho^2,\quad\lambda\in\mathbb{R},$$

$\Omega =\mathbb {R}^N$

$\mathbb {R}^N\setminus \Omega$

$\rho >0$

$V\ge 0$

$V\equiv 0$

$p\in (2,2+\frac 4 N)$

$\bar u$

$V$

$\|V\|_{L^q}$

$q\ge \frac N2$

$q>1$

$N=2$

$V$

$\mathbb {R}^N\setminus \Omega$

$\bar u$

$V\equiv 0$

$\Omega =\mathbb {R}^N$

The new genus Nimisora Pérez-Ort., M. Svenss. & J. C. Zamora is introduced to accommodate a puzzling lecideoid epiphyte common in the central Iberian Peninsula. Nimisora is characterized by the following combination of characters: lecideoid apothecia, excipulum composed of sparingly branched radiating hyphae with narrow lumina, thick walls and swollen terminal cells, the presence of a brown K+ olivaceous green pigment in the epihymenium, an ascus tip similar to the Bacidia-type, and the presence of simple ellipsoid ascospores. Molecular analyses based on nrITS, nrLSU and mtSSU sequences unequivocally place the new genus within the Lecanoraceae; however, its phylogenetic affinities with other genera of the family remain largely unresolved. Comparisons with the morphologically closest genera are provided. The single species of the genus, Nimisora iberica Pérez-Ort., Turégano, M. Svenss. & J. C. Zamora sp. nov., is also described as new to science.

Environmental control strategies are commonly practised to limit biodeterioration issues threatening indoor cultural heritage objects, while they are still poorly exploited for the conservation of outdoor stone heritage surfaces, including rock art. In this study, we evaluated the environmental factors driving the diversity and abundance of lithobiontic communities in the Rock Engravings National Park of Naquane (UNESCO WHS n. 94, Italy). The survey considered 23 rocks that had been cleaned in the last three (3YC) or twelve (12YC) years or more than 40 years ago (NRC). A cyanobacteria-dominated biofilm and lichens (37 taxa) were the most widespread and abundant lithobiontic components, prevailing on 3YC–12YC and NRC rocks, respectively. On the latter, a turnover of xerophytic and meso-hygrophytic lichen communities was observed. On 3YC–12YC rocks lichen colonization, if present, was limited to nitrophytic species, including common epiphytes from surrounding trees and a small number of meso-hygrophytic species, with a prevalence of asexual reproductive strategies. Multivariate analyses including environmental parameters (canonical correspondence analyses) indicated that tree cover and the presence of bare or vegetated ground upstream of the rocks, probably prolonging wetness and providing nutrients by water transport, are the factors mostly related to the microbial and lichen recolonization of 3YC–12YC surfaces. On this basis, an experiment on preventive conservation was conducted, consisting of a new cleaning of a strongly recolonized 3YC surface combined with the building of a small wall to protect part of the rock from prolonged water fluxes. The fluorimetric and colorimetric monitoring of the rock surface, carried out 40 months after this new cleaning intervention, displayed recolonization on the unprotected area only, indicating the potential of preventive conservation strategies in outdoor environments.

Dictatorships that use plebiscites – that is, referendums initiated by the executive – have a longer expected lifespan. A successful plebiscite sends a signal that makes coordination for collective action more difficult and induces the falsification of preferences. It also enhances the status of the dictator within the regime and against potential rivals through the use of agenda power. As a result, plebiscites are followed by decreased mobilization and a reduced risk of palace coups. This, in turn, adds years to the dictator's tenure. We have found evidence to support these propositions by utilizing data from various databases of autocratic regimes that span from 1946 to 2008.

The local classification of Kaehler submanifolds $M^{2n}$ of the hyperbolic space $\mathbb{H}^{2n+p}$ with low codimension $2\leq p\leq n-1$ under only intrinsic assumptions remains a wide open problem. The situation is quite different for submanifolds in the round sphere $\mathbb{S}^{2n+p}$, $2\leq p\leq n-1$, since Florit et al. [7] have shown that the codimension has to be $p=n-1$ and then that any submanifold is just part of an extrinsic product of two-dimensional umbilical spheres in $\mathbb{S}^{3n-1}\subset\mathbb{R}^{3n}$. The main result of this paper is a version for Kaehler manifolds isometrically immersed into the hyperbolic ambient space of the result in [7] for spherical submanifolds. Besides, we generalize several results obtained by Dajczer and Vlachos [5].

The present work aims to prospect and study the plastic and superplastic clay deposits in the state of São Paulo, Brazil, as a source of raw materials for the ceramic tile industry and especially for the production of porcelain stoneware tiles. To achieve the proposed objectives, a geological study was carried out through the mapping and identification of the present lithologies, lithogeochemical characterization using X-ray diffraction, inductively coupled plasma optical emission spectrometry, cation-exchange capacity and organic carbon and characterization of the ceramic technological properties, including granulometric analysis by sedigraph and Brunauer–Emmett–Teller specific surface area. According to their geological characteristics, the studied deposits were classified into two types: a detrital sedimentary deposit, restricted to Quaternary alluvial sediments and Neogenic Tertiary formations and composed of silt-sandy clay and plastic, kaolinitic, refractory and silico-aluminous facies; and an alterite type, found in Permo-Carboniferous rocks of the Paraná Basin, composed of laminated/massive weathering siltstones, with the highly plastic, fluxing clay minerals illite, kaolinite and smectites. Among the targets studied in these deposits, argillaceous facies with plastic and superplastic characteristics were identified, which affect their applicability in compositions for producing porcelain stoneware tiles and stoneware.

Data exchange, the problem of transferring data from a source schema to a target schema, has been studied for several years. The semantics of answering positive queries over the target schema has been defined in early work, but little attention has been paid to more general queries. A few proposals of semantics for more general queries exist but they either do not properly extend the standard semantics under positive queries, giving rise to counterintuitive answers, or they make query answering undecidable even for the most important data exchange settings, for example, with weakly-acyclic dependencies.

The goal of this paper is to provide a new semantics for data exchange that is able to deal with general queries. At the same time, we want our semantics to coincide with the classical one when focusing on positive queries, and to not trade-off too much in terms of complexity of query answering. We show that query answering is undecidable in general under the new semantics, but it is $\text{co}\text{NP}\text{-complete}$ when the dependencies are weakly-acyclic. Moreover, in the latter case, we show that exact answers under our semantics can be computed by means of logic programs with choice, thus exploiting existing efficient systems. For more efficient computations, we also show that our semantics allows for the construction of a representative target instance, similar in spirit to a universal solution, that can be exploited for computing approximate answers in polynomial time.

We derive explicit formulae for the mean profiles of passive scalars (either temperature or concentration of a diffusing substance), and their respective wall fluxes (either heat or mass fluxes), in forced turbulent convection, as a function of the Reynolds and Prandtl numbers. Direct numerical simulation data for turbulent flow within a smooth straight pipe of circular cross-section, at friction Reynolds number ${{Re}}_{\tau }=1140$, in the range of Prandtl numbers from ${{Pr}}=0.00625$ to ${{Pr}}=16$, are used to infer the proper analytical form of the eddy diffusivity. This is leveraged to derive accurate predictive formulae for the mean passive scalar profiles, and for the corresponding logarithmic offset function. Asymptotic scaling laws result for the thickness of the conductive (diffusive) layer, and for the Nusselt number, which significantly extend the predictive envelope of classical formulae.

Monitoring the concentration of glucocorticoid metabolites (GCMs) in faecal samples is a non-invasive tool for physiological stress evaluation, particularly useful when studying wild species. However, both negative and positive stimuli (distress and eustress, respectively) can lead to a rise in glucocorticoids. Thus, besides validating whether GCM concentration in faeces reflects endogenous adrenal activity, we also need to identify behavioural indicators of distress to avoid misinterpretation. Therefore, we submitted four adult male spotted pacas (Cuniculus paca) to an exogenous adrenocorticotropic hormone (ACTH) challenge-test in a Latin square design (4 × 4) to monitor changes in the GCM concentration in faeces. We also aimed to describe behaviours potentially indicative of distress. We collected excreted faeces and video-recorded the animals’ behaviours for five consecutive days, one day before and four days after application of the following four treatments: 1st control (no-handling); 2nd control (intra-muscular [IM] injection of saline solution); low-dose ACTH (IM injection of 0.18 ml ACTH); and high-dose ACTH (IM injection of 0.37 ml ACTH). There was a peak in the concentration of GCM in faeces collected 24 h after the injection of the high-dose ACTH treatment. Additionally, independent of the treatments, spotted pacas spent less time on exploration and feeding states, while spending more time in the inactive but awake (IBA) state following the treatment application (challenge day). The use of GCM concentration in faecal samples together with the behavioural changes (less exploration and feeding, and more IBA) showed to be efficient as a non-invasive tool for welfare assessment of farmed spotted paca.

In the early weeks of the 2020 coronavirus (COVID-19) pandemic, the Fox News Channel advanced a skeptical narrative that downplayed the risks posed by the virus. We find that this narrative had significant consequences: in localities with higher Fox News viewership—exogenous due to random variation in channel positioning—people were less likely to adopt behaviors geared toward social distancing (e.g., staying at home) and consumed fewer goods in preparation (e.g., cleaning products, hand sanitizers, and masks). Using original survey data, we find that the effect of Fox News came not merely from its long-standing distrustful stance toward science, but also due to program-specific content that minimized the COVID-19 threat. Taken together, our results demonstrate the significant impact that misinformation in media coverage can exert on viewers’ beliefs and behavior, even in high-stakes situations.