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In this article, the author introduces the debate on dialect choice in the teaching of Spanish. He first presents an early 20th-century proposal by Spanish philologist Ramón Menéndez Pidal (1918) and then moves to two recent discussions: one within the Instituto Cervantes in the context of the international promotion of Spanish, and another in the context provided by the growth of the teaching of Spanish to heritage speakers in the United States. After considering the MLA (2007, 2009) reports on the role of languages in higher education, the author concludes by embracing pedagogical options where, regardless of the choice of one particular norm, discussion of the development and operation of linguistic regimes becomes central in language instruction from the very early stages of the language program's curricular structure. (Verlag, adapt.).

Flower color arises primarily from pigments that serve dual functions: attracting pollinators and mitigating environmental stresses. Among major pigment types, anthocyanins and UV-absorbing phenylpropanoids (UAPs) fulfill one or both roles and should be widespread. Our review of the UV-vis absorption profiles of major floral pigments demonstrates that UAPs are the primary UV protectants. Next, we analyzed the floral pigment composition of 926 animal-pollinated species from California, Southern Spain, and Southeastern Brazil. UAPs were ubiquitous (the “dark matter” of the flower). Among the remaining pigment types, ~ 56% of species had anthocyanins, ~ 37% had carotenoids, and ~ 17% had chlorophylls (some species had > 1 pigment type). Pigment abundance varied in response to abiotic and biotic factors, particularly with pollinator type in California. Despite regional differences in environmental filtering, pollination guilds, and relatedness, UAPs are omnipresent and there is a transcontinental stable distribution of flower colors and their underlying floral pigments.

The Doñana Biosphere Reserve is one of the most recognized and studied natural areas in the world, hence the importance of having an openly accessible species checklist. Previous lists are outdated, often have limited taxonomic scope, lack clearly defined inclusion and exclusion criteria, or are practically inaccessible. Here, an updated checklist of vertebrate species for the Doñana Biosphere Reserve based on explicit spatial, temporal, and biological criteria is presented, reviewed and complemented by expert zoologists. The resulting inventory includes 700 vertebrate species, with birds (60%) and fishes (26%) being the most diverse groups. Seven species are considered extinct in the region, two are possibly extinct (i.e., have not been recorded in the past decade), and 32 are classified as exotic. This updated and curated checklist fills a critical gap in regional biodiversity knowledge and establishes a robust foundation for future monitoring, research, and conservation efforts in this ecologically unique and increasingly threatened area of southwestern Europe.

Background Anthocyanins are the primary source of colour in flowers and also accumulate in vegetative tissues, where they have multiple protective roles traditionally attributed to early compounds of the metabolic pathway (flavonols, flavones, etc.). Petal-specific loss of anthocyanins in petals allows plants to escape from the negative pleiotropic effects of flavonoid and anthocyanins loss in vegetative organs, where they perform a plethora of essential functions. Herein, we investigate the degree of pleiotropy at the biochemical scale in a pink-white flower colour polymorphism in the shore campion, Silene littorea . We report the frequencies of pink and white individuals across 21 populations and underlying biochemical profiles of three flower colour variants: anthocyanins present in all tissues (pink petals), petal-specific loss of anthocyanins (white petals), and loss of anthocyanins in all tissues (white petals). Results Individuals lacking anthocyanins only in petals represent a stable polymorphism in two populations at the northern edge of the species range (mean frequency 8–21%). Whereas, individuals lacking anthocyanins in the whole plant were found across the species range, yet always at very low frequencies (< 1%). Biochemically, the flavonoids detected were anthocyanins and flavones; in pigmented individuals, concentrations of flavones were 14–56× higher than anthocyanins across tissues with differences of > 100× detected in leaves. Loss of anthocyanin pigmentation, either in petals or in the whole plant, does not influence the ability of these phenotypes to synthesize flavones, and this pattern was congruent among all sampled populations. Conclusions We found that all colour variants showed similar flavone profiles, either in petals or in the whole plant, and only the flower colour variant with anthocyanins in photosynthetic tissues persists as a stable flower colour polymorphism. These findings suggest that anthocyanins in photosynthetic tissues, not flavonoid intermediates, are the targets of non-pollinator mediated selection.

Mass transfer models on supercritical carbon dioxide (SC-CO 2 ) extraction of vegetable oils are reviewed, that may facilitate the scale-up of laboratory data for industrial design purposes. Reviewed mechanisms of oil transport within the solid matrix include the desorption from the solid, the formation of a shrinking core of condensed oil in a non-adsorbing porous matrix, and diffusion in a homogenous medium. Analyzed simplificat ions of a general mass transfer model include external control of mass transfer rates, internal control of mass transfer rates, consideration of a linear driving force, and steady state approximations, among others. More complex two-stage models, and critical comparisons of some of the proposed models are also included. Trends for the external mass transfer coefficient and effective diffusivity in the solid matrix from studies on SC-CO 2 extraction of oil from vegetable substrates are thoroughly discussed and contrasted with those obtained using simpler model systems. The possible effect of the axial dispersion on the rate of extraction is also discussed. Finally, the high-pressure vegetable oil-CO 2 phase equilibrium is discussed in connection with its influence on the mass transfer process. Special emphasis is given to the role of the solid matrix on high-pressure phase equilibrium.

The species Agave angustifolia can be propagated asexually with offshoots from rhizomes, bulbils from inflorescence, and through micropropagation to supply the growing demand for quality plant material for new plantations. In this investigation, Agave angustifolia plants of different initial sizes were evaluated for growth and emission of rhizome shoots, after 14 months under different conditions of substrate, fertigation and application of cytokinins. Bulbils were collected from inflorescences of plants at two sites and classified into two size categories: small (< 7 cm) and large (> 7 cm). The bulbils were cultured for 14 months in pots with substrates that were mixtures of sand (A), soil (S), and bovine manure (Bm) (%): 1) A + S (0.3: 0.7); 2) A + S + Bm (0.3: 0.525: 0.175); 3) A + S + Bm (0.3: 0.35: 0.35); 4) A + S + Bm (0.3: 0.175: 0.525). The plants in each substrate were separated into groups for application of different types of irrigation: 1) water; 2) 50% Steiner's nutritive solution, SNS-50%; 3) SNS-50% + 25 mg L-1 of benzylaminopurine. The results show that the emission of rhizome offshoots was affected by the substrate, type of irrigation and provenance of the plants. The plants in substrates 3 and 4 formed 2.2 rhizome offshoots, which was more than plants in the other substrates. The plants irrigated with water, SNS-50%, and SNS-50% + benzylaminopurine formed 1.1, 1.6 and 1.9 rhizome offshoots, respectively.

Spanish is spoken as a first language by almost 400 million people in approximately 60 countries, and has been the subject of numerous political processes and debates since it began to spread globally from Iberia in the thirteenth century. A Political History of Spanish brings together a team of experts to analyze the metalinguistic origins of Spanish and evaluate it as a discursively constructed artefact; that is to say, as a language which contains traces of the society in which it is produced, and of the discursive traditions that are often involved and invoked in its creation. This is a comprehensive and provocative new work which takes a fresh look at Spanish from specific political and historical perspectives, combining the traditional chronological organization of linguistic history and spatial categories such as Iberia, Latin America and the US, whilst simultaneously identifying the limits of these organizational principles.

Objective. To provide information about the incidence and predictors of liver decompensation and death due to liver failure in human immunodeficiency virus (HIV)-infected patients with compensated hepatitis C virus (HCV)-related cirrhosis. Methods. Prospective cohort study of 154 HIV-HCV-coinfected patients with a new diagnosis of Child-Pugh-Turcotte (CPT) class A compensated cirrhosis. We evaluated time from diagnosis to the first liver decompensation and death from liver disease, as well as predictors of these outcomes. Results. Thirty-six patients (23.4%) developed liver decompensation. The incidence of liver decompensation was 6.40 cases per 100 person-years (95% confidence interval [CI], 4.18–9.38 cases per 100 person-years). Factors independently associated with liver decompensation were lack of HCV therapy (hazard ratio [HR], 3.38; 95% CI, 1.09–10.53; P=.035), baseline CD4 cell counts ⩽300 cells/mm3(HR, 2.12; 95% CI, 1.14–5.04; P=.021), CPT score 6 versus 5 (HR, 3.33; 95% CI, 1.39–7.69; P=.007), and a diagnosis of cirrhosis based on data other than biopsy or transient elastography (HR, 2.09; 95% CI, 1.05–4.16; P=.036). Fifteen patients (9.7%) died; 11 (73%) of these 15 died from liver disease (mortality due to liver failure, 2.44 deaths per 100 person-years; 95% CI, 1.21–4.36 deaths per 100 person-years). Hepatic encephalopathy as the first liver decompensation (HR, 20.67; 95% CI, 2.71–157.57; P=.003), baseline CD4 count ⩽300/mm3(HR, 0.24; 95% CI, 0.07–0.78; P=.017), and baseline CPT score 6 (HR, 4.50; 95% CI, 1.63–12.37; P=.004) were independently associated with liver-related death. Conclusions. The incidence of clinical liver events in HIV-HCV-coinfected patients with CPT class A compensated cirrhosis is close to that previously reported in HCV-monoinfected patients. Lower baseline CD4 cell counts, lack of therapy against HCV, and higher CPT score are the factors related to the occurrence of clinical liver events. Minimal changes in CPT score have strong impact in the prognosis of this population.

Barriers between islands often inhibit gene flow creating patterns of isolation by distance. In island species, the majority of genetic diversity should be distributed among isolated populations. However, a self-incompatible mating system leads to higher genetic variation within populations and very little between-population subdivision. We examine these two contrasting predictions in Erysimum teretifolium, a rare self-incompatible plant endemic to island-like sandhill habitats in Santa Cruz County, California. We used genome skimming and nuclear microsatellites to assess the distribution of genetic diversity within and among eight of the 13 remaining populations. Phylogenetic analyses of the chloroplast genomes revealed a deep separation of three of the eight populations. The nuclear ribosomal DNA cistron showed no genetic subdivision. Nuclear microsatellites suggest 83% of genetic variation resides within populations. Despite this, 18 of 28 between-population comparisons exhibited significant population structure (mean FST = 0.153). No isolation by distance existed among all populations, however when one outlier population was removed from the analysis due to uncertain provenance, significant isolation by distance emerged (r2 = 0.5611, p = 0.005). Population census size did not correlate with allelic richness as predicted on islands. Bayesian population assignment detected six genetic groupings with substantial admixture. Unique genetic clusters were concentrated at the periphery of the species' range. Since the overall distribution of nuclear genetic diversity reflects E. tereifolium's self-incompatible mating system, the vast majority of genetic variation could be sampled within any individual population. Yet, the chloroplast genome results suggest a deep split and some of the nuclear microsatellite analyses indicate some island-like patterns of genetic diversity. Restoration efforts intending to maximize genetic variation should include representatives from both lineages of the chloroplast genome and, for maximum nuclear genetic diversity, should include representatives of the smaller, peripheral populations.

Plants respond to changes in ultraviolet (UV) radiation both morphologically and physiologically. Among the variety of plant UV-responses, the synthesis of UV-absorbing flavonoids constitutes an effective non-enzymatic mechanism to mitigate photoinhibitory and photooxidative damage caused by UV stress, either reducing the penetration of incident UV radiation or acting as quenchers of reactive oxygen species (ROS). In this study, we designed a UV-exclusion experiment to investigate the effects of UV radiation in Silene littorea. We spectrophotometrically quantified concentrations of both anthocyanins and UV-absorbing phenolic compounds in petals, calyces, leaves and stems. Furthermore, we analyzed the UV effect on the photosynthetic activity in hours of maximum solar radiation and we tested the impact of UV radiation on male and female reproductive performance. We found that anthocyanin concentrations showed a significant decrease of about 20% with UV-exclusion in petals and stems, and a 30% decrease in calyces. The concentrations of UV-absorbing compounds under UV-exclusion decreased by approximately 25% in calyces and stems, and 12% in leaves. Photochemical efficiency of plants grown under UV decreased at maximum light stress, reaching an inhibition of 58% of photosynthetic activity, but their ability to recover after light-stress was not affected. In addition, exposure to UV radiation did not affect ovule production or seed set per flower, but decreased pollen production and total seed production per plant by 31% and 69%, respectively. Our results demonstrate that UV exposure produced opposing effects on the accumulation of plant phenolic compounds and reproduction. UV radiation increased the concentration of phenolic compounds, suggesting a photoprotective role of plant phenolics against UV light, yet overall reproduction was compromised.