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1.
Epilepsy Behav ; 151: 109587, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159506

RESUMO

INTRODUCTION: Temporal Lobe Epilepsy (TLE) has been associated with memory impairments, which are typically linked to hippocampal and mesial temporal cortex lesions. Considering the presence of extensive bidirectional frontotemporal connections, it can be hypothesized that executive dysfunction in TLE is modulated by the lateralization of the epileptic foci. MATERIAL AND METHODS: A comprehensive neuropsychological executive functions protocol was administered to 63 participants, including 42 individuals with temporal lobe epilepsy (20 with right-TLE and 22 with left-TLE) and 21 healthy controls aged 20-49. RESULTS: The results indicate that TLE patients exhibit poorer executive performance compared to healthy controls in working memory (F(2,60) = 4.18, p <.01), planning (F(2,60) = 4.71, p <.05), set shifting (F(2,60) = 10.1, p <.001), phonetic verbal fluency (F(2,60) = 11.71, p <.01) and semantic verbal fluency (F(2,60) = 9.61, p <.001. No significant differences were found in cognitive inhibition. Furthermore, right-TLE patients showed lower performance than left-TLE in set shifting (F(1,61) = 6.45, p <.05), while no significant differences were observed in working memory, planning, inhibition, and verbal fluency. CONCLUSIONS: This research emphasize the importance of considering the lateralization of the temporal lobe focus to achieve a more accurate neuropsychological characterization. The cognitive differences between left and right TLE patients highlight the need for individualized approaches in their treatment and care.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Função Executiva/fisiologia , Testes Neuropsicológicos , Lobo Temporal , Cognição/fisiologia
2.
Plants (Basel) ; 12(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38068605

RESUMO

Tamarix is native to Eurasia plus the northern and southern territories of Africa, with some species being introduced into America and Oceania. They are usually found in arid, desertic, or subdesertic areas, often on saline or subsaline soils, in Mediterranean, temperate, or subtropical climates. The genus is renowned for its complex taxonomy, which is usually based on rather variable or unstable characters, which leads to contrasting taxonomic treatments. As part of the taxonomic revision of Tamarix undertaken by the authors, ten names (i.e., T. africana, T. bounopoea, T. brachystylis var. fluminensis, T. malenconiana, T. muluyana, T. tenuifolia, T. tingitana, T. trabutii, T. valdesquamigera, and T. weyleri) published from material collected in the southwestern parts of the Mediterranean basin are taxonomically and nomenclaturally discussed after analysing their original material. Eight intended holotypes are corrected here to lectotypes; one epitype is designated for T. africana to warrant current use of the name; and one isotype, 30 isolectotypes, and 11 syntypes are also identified for the studied names. Further, the taxonomic identity of all names and their eventual synonymic placement are accordingly discussed.

3.
Biology (Basel) ; 12(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37759580

RESUMO

Physiological variables (the content of chlorophyll, flavonoids and nitrogen, together with Fv/Fm) and the content of ten heavy metals (As, Cd, Cu, Hg, Mn, Ni, Pb, Sb, V and Zn) and two platinum group elements (PGEs: Pd and Rh) were measured in the leaves of 50 individuals of Ligustrum lucidum trees regularly distributed in the city of Logroño (Northern Spain). Three of these variables increased with increasing physiological vitality (chlorophyll, nitrogen and Fv/Fm), whereas flavonoids increased in response to different abiotic stresses, including pollution. Our aim was to test their adequacy as proxies for the pollution due to heavy metals and PGEs. The three vitality indicators generally showed high values typical of healthy plants, and they did not seem to be consistently affected by the different pollutants. In fact, the three vitality variables were positively correlated with the first factor of a PCA that was dominated by heavy metals (mainly Pb, but also Sb, V and Ni). In addition, Fv/Fm was negatively correlated with the second factor of the PCA, which was dominated by PGEs, but the trees showing Fv/Fm values below the damage threshold did not coincide with those showing high PGE content. Regarding flavonoid content, it was negatively correlated with PCA factors dominated by heavy metals, which did not confirm its role as a protectant against metal stress. The relatively low levels of pollution usually found in the city of Logroño, together with the influence of other environmental factors and the relative tolerance of Ligustrum lucidum to modest atmospheric pollution, probably determined the only slight response of the physiological variables to heavy metals and PGEs.

4.
Plants (Basel) ; 12(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37514245

RESUMO

The taxonomic identity and phylogenetic relationships of several southern African perennial taxa related to Frankenia repens are discussed. In particular, F. nodiflora Lam., a misunderstood species described from the Cape region and synonymised to F. pulverulenta, is restored for plants endemic to salt-pans and riverbeds in the coastal lowlands across the Cape Flats (Western Cape province, South Africa). Further, a revision of morphologically close plants, usually identified as F. pulverulenta or F. repens, also occurring in similar saline ecosystems of the inland western South Africa revealed the existence of two distinct new entities not matching any described taxa of the genus. Molecular analyses of nuclear ribosomal (ITS1-5.8S-ITS2 region) DNA sequence data together with morphological divergence allow recognition of those taxa at species rank, within an independent lineage close to F. repens. In consequence, two new sea-heath species are described in the so-called "F. repens group": F. nummularia from the Nama-Karoo Biome (Western Cape and Northern Cape provinces), and F. anneliseae from the Succulent Karoo Biome (Northern Cape province). Full morphological description and type designation are reported for each accepted species as well as data on ecology, habitat, distribution, and taxonomic relationships to other close relatives are given. Further, an identification key is presented to facilitate recognition of the southern African taxa of Frankenia.

5.
Plants (Basel) ; 12(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37447042

RESUMO

The name "Spergularia hanoverensis Simon" has been misapplied to an endemic taxon confined to inland semidesert ecosystems in central-western South Africa. It is commonly accepted as a small annual species occurring in saline habitats in a wide elevation range, but its identity still remains obscure. In the context of taxonomic and phylogenetic research on the African species of Spergularia, we found that the name was never validly published. After revision of herbarium material housed in South African herbaria, a voucher collected from Hanover was found at PRE bearing some labels handwritten by E. Simon that suggest it might be an intended type for the name. Additional herbarium material and wild populations from the Karoo region were identified that matched the samples in that voucher, and taxonomic research was conducted to clarify their identity. Among other characters, those Karoo plants show a woody dense compact habit, woody perennial at base; stems prostrate to ascendent; leaves entirely glabrous, somewhat glaucous; large white-hyaline conspicuous stipules; inflorescence glanduliferous, many-flowered subdichasial cyme, with minute bracts; flowers small, with white petals approximately equalling sepals in length, stamens 7-8, and styles free from base; capsule small, with seeds dimorphic, unwinged to broadly winged, with testa always densely tuberculate. Molecular analyses of plastid (trnL-trnF region) and nuclear ribosomal (5.8S-ITS2 region) DNA sequence data support morphological differentiation of the Karoo plants, for which the name S. hanoverensis is here effectively published. A full morphological description and data on ecology, habitat, distribution, and taxonomic and phylogenetic relationships of S. hanoverensis are compared to other members of the "South African group", namely S. glandulosa, S. namaquensis, and S. quartzicola, from which the new species considerably differs. The adaptative significance of dimorphic seeds of S. hanoverensis is briefly commented on in the context of the species habitat preference. An identification key is presented for the South African related taxa.

6.
Memory ; 30(2): 217-228, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023367

RESUMO

Drawing a hypothesis from embodied theories of memory, van Dam, Rueschemeyer, Bekkering and Lindemann [(2013). Embodied grounding of memory: Toward the effects of motor execution on memory consolidation. The Quarterly Journal of Experimental Psychology, 66(12), 2310-2328] showed that recognition performance for action words could be modulated by actions performed during the retention interval, suggesting that motor actions during the retention interval affect memory consolidation. The results of 4 experiments from two different laboratories, designed to replicate and extend the van Dam et al. motor consolidation effect, are presented here. Two of the experiments (n = 30 and n = 44) exactly and independently replicated the experimental design and conditions of the original experiment. Yes/No recognition scores plus additional analysis of response times showed no motor consolidation effects. A third experiment (n = 44) manipulating type of processing during encoding also failed to find significant motor consolidation effects. Finally, a fourth experiment (n = 120) following a more standard reconsolidation paradigm, involving 24-hour intervals between learning and motor behaviour, and a 24-hour delayed test, also found null effects. The absence of effects of motor execution on memory consolidation is discussed in terms of the implications of these findings for the embodiment approach to cognition.


Assuntos
Aprendizagem , Consolidação da Memória , Humanos , Consolidação da Memória/fisiologia , Atividade Motora , Tempo de Reação , Reconhecimento Psicológico
7.
Front Psychol ; 12: 718118, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603142

RESUMO

Non-invasive transcranial direct current stimulation (tDCS) over the left anterior temporal lobe (ATL) has been shown to cause a reduction in the rate of false memories with semantically related words. Such a reduction seems to be specific to false memories induced by the study of associative lists, but is not observed when the studied lists are categorical in nature. These findings are interpreted as evidence that the left ATL functions as an integration hub that is crucial for the binding of semantic information into coherent representations of concepts. In order to investigate whether the right ATL might also contribute to semantic integration in the processing of verbal associative material, a follow-up tDCS study was conducted with the stimulation at study lateralized on the right ATL. A sample of 75 undergraduate students participated in an experiment in which they studied 8 associative lists and 8 categorical lists. One third of the participants studied all their word lists under anodal stimulation, another third studied under cathodal stimulation and the other third under sham stimulation. Results showed that stimulation of the right ATL by tDCS does not modulate false recognition for either association-related critical words or category-related critical words. These results provide preliminary support to views positing asymmetric connectivity between the anterior temporal lobes and the semantic representational network, and provide evidence for understanding bilateral brain dynamics and the nature of semantically induced memory distortions.

8.
Plants (Basel) ; 10(8)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34451723

RESUMO

Ultraviolet (UV) radiation strongly influences grape composition, but only a few studies have focused on how this influence is conserved in the resulting wines. Here we analyzed to what extent the changes induced by exposing Tempranillo grapes to UV radiation from budbreak to harvest were conserved in wine. By using different cut-off filters and lamps, we differentiated the effects of ambient levels of UV-A and UV-B wavelengths, as well as the effects of a realistic UV-B enhancement associated with climate change. Among phenolic compounds, the most consistent responses to UV were those of flavonols (particularly quercetin-, kaempferol-, isorhamnetin- and myricetin-glycosides), which significantly increased in wines whose grapes had been exposed to a synergic combination of UV-A and UV-B radiation. This confirms that flavonols are the phenolic compounds most reliably conserved from UV-exposed grapes to wine, despite the possible influence of the winemaking process. Flavonols are important compounds because they contribute to wine co-pigmentation by stabilizing anthocyanins, and they are interesting antioxidants and nutraceuticals. Hydroxycinnamic acids also increased under the same UV combination or under UV-A alone. Wine VOCs were much less reactive to the UV received by grapes than phenolic compounds, and only esters showed significantly higher values under (mainly) UV-A alone. This was surprising because (1) UV-A has been considered to be less important than UV-B to induce metabolic changes in plants, and (2) esters are produced during winemaking. Esters are relevant due to their contribution to the fruity aroma in wines. In general, the remaining phenolic compounds (stilbenes, flavanols, hydroxybenzoic acids, and anthocyanins) and VOCs (alcohols, hydrocarbons, and fatty acids), together with wine color and antioxidant capacity, showed inconsistent or non-significant responses to UV radiation. These results were summarized by a multivariate analysis. Our study opens up new possibilities to artificially manipulate UV radiation in grapevine cultivation to improve both grape and wine quality.

9.
Physiol Plant ; 173(3): 709-724, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34145583

RESUMO

The effects of UV radiation on Vitis vinifera cv Tempranillo grapes were studied under field conditions as influenced by ultraviolet (UV) band (UV-A and UV-B), UV-B level (ambient vs enhanced), grape phenological stage (pea-size, veraison, and harvest), grape component (skin, flesh, and seeds), and fraction from which phenolic UV-absorbing compounds (UVACs) were extracted (soluble vs insoluble). Ambient UV-B levels caused stronger effects than ambient UV-A. These effects included increases in flavonol contents (particularly quercetins and kaempferols), the expression of flavonol synthase and chalcone synthase genes (VvFLS4 and VvCHS1), and grape weight and size. In addition, the contents of flavanols and hydroxycinnamic acids increased under UV-B radiation at pea-size stage. All these compounds play physiological roles as antioxidants and UV screens. Synergic effects between UV-B and UV-A were observed. The responses of anthocyanins, stilbenes, and volatile compounds to UV were diffuse or nonexistent. Enhanced UV-B led to rather subtle changes in comparison with ambient UV-B, but differences between both treatments could be demonstrated by multivariate analysis. Pea-size and harvest were the phenological stages where the most significant responses to UV were found, while the skin was the most UV-responsive grape component. Soluble phenolic compounds were much more UV-responsive than insoluble compounds. In conclusion, UV radiation was essential for the induction of specific grape phenolic and volatile compounds. Given the physiological roles of these compounds, as well as their contribution to grape and wine quality, and their potential use as nutraceuticals, our results may have implications on the artificial manipulation of UV radiation.


Assuntos
Vitis , Antocianinas , Frutas , Fenóis , Raios Ultravioleta , Vitis/genética
10.
Plants (Basel) ; 10(3)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802248

RESUMO

The liverwort Marchantia polymorpha subsp. ruderalis is an emerging model plant, and some data are available on its responses to ultraviolet (UV) radiation. However, it is unknown if the developmental stage of the thalli modulates the effects of UV radiation on the contents of potentially protecting phenolic compounds. To fill this gap, liverwort samples were exposed or non-exposed to UV radiation for 38 days under controlled conditions, using three developmental stages: gemmae (G), one-month thalli (T1), and two-month thalli (T2). Then, the bulk level of methanol-soluble UV-absorbing compounds and the contents of six flavones (apigenin and luteolin derivatives) were measured. The UV responsiveness decreased with thallus age: G and T1 plants were the most UV-responsive and showed a strong increase in all the variables, with G plants more responsive than T1 plants. In UV-exposed T2 plants, only apigenin derivatives increased and more modestly, probably due to a lower acclimation capacity. Nevertheless, the thalli became progressively tougher due to a decreasing water content, representing a possible structural protection against UV. In UV-exposed plants, the temporal patterns of the accumulation of phenolic compounds were compound-specific. Most compounds decreased with thallus age, but di-glucuronide derivatives showed a bell-shaped pattern, with T1 plants showing the highest contents. A Principal Components Analysis (PCA) ordination of the different samples summarized the results found. The patterns described above should be taken into account to select thalli of an adequate developmental stage for experiments investigating the induction of phenolic compounds by UV radiation.

11.
J Sci Food Agric ; 100(1): 401-409, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31637723

RESUMO

BACKGROUND: It is widely recognized that ambient levels of solar ultraviolet (UV) radiation strongly influence the phenolic composition of grape skins. However, it is unknown to what extent this influence is reflected in the resulting wines. RESULTS: Tempranillo grapevines were exposed or non-exposed to close-to-ambient solar UV levels using appropriate filters, and the phenolic profiles and antioxidant capacity of both grape skins and the resulting wines were analyzed. In total, 47 phenolic compounds were identified in skins and wines, including flavonols, anthocyanins, flavanols, stilbenes, and hydroxycinnamic and hydroxybenzoic acids. In UV-exposed grape skins, flavonols and anthocyanins increased, whereas flavanols and hydroxybenzoic acids showed no significant change. These characteristics were conserved in the resulting wines. However, for stilbenes, hydroxycinnamic acids and antioxidant capacity, the effect of UV on grape skins was not conserved in wines, probably as a result of changes during winemaking. In addition, color intensity, total phenols and total polyphenol index of wines elaborated from UV-exposed grapes increased (although non-significantly) compared to those made from non-UV-exposed grapes. CONCLUSION: The phenolic composition of grape skins exposed to close-to-ambient solar UV could predict, to some extent, the phenolic composition of the resulting wines, particularly regarding higher contents of flavonols and anthocyanins. Thus, manipulating the UV radiation received by grape skins could improve wine quality by positively influencing color stability and healthy properties. To our knowledge, this is the first study in which the effects of solar UV radiation on phenolic composition have been assessed from grape skins to wine. © 2019 Society of Chemical Industry.


Assuntos
Frutas/efeitos da radiação , Fenóis/química , Vitis/química , Vinho/análise , Antocianinas/química , Antioxidantes/química , Flavonóis/química , Frutas/química , Polifenóis/química , Estilbenos/química , Raios Ultravioleta , Vitis/efeitos da radiação
12.
Front Plant Sci ; 10: 998, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428117

RESUMO

We studied the acclimation modalities of bryophytes to sun and shade under ambient or close-to-ambient conditions, measuring variables usually influenced by photosynthetically active (PAR) and ultraviolet (UV) radiations. Our aim was to elucidate to what extent the responses to changing radiations were influenced by PAR and UV wavelengths. For this aim, we used three taxonomically and structurally different species: the thalloid liverwort Marchantia polymorpha subsp. polymorpha, the leafy liverwort Jungermannia exsertifolia subsp. cordifolia, and the moss Fontinalis antipyretica. In the field, liverworts were more radiation-responsive than the moss, and the thalloid liverwort was more responsive than the leafy liverwort. Sun plants of M. polymorpha showed, in comparison to shade plants, higher sclerophylly, lower Chl a + b contents, higher Chl a/b ratios, higher (antheraxanthin + zeaxanthin)/(violaxanthin + antheraxanthin + zeaxanthin) ratios (xanthophyll index), lower F v/F m values, higher contents of methanol-soluble vacuolar UV-absorbing compounds (soluble UVACs), higher values of the ratio between the contents of methanol-insoluble cell wall-bound UVACs (insoluble UVACs) and soluble UVACs, higher contents of soluble luteolin and apigenin derivatives and riccionidin A, and higher contents of insoluble p-coumaric and ferulic acids. Overall, these responses reduced light absorption, alleviated overexcitation, increased photoprotection through non-photochemical energy dissipation, increased UV protection through UV screening and antioxidant capacity, and denoted photoinhibition. J. exsertifolia showed moderate differences between sun and shade plants, while responses of F. antipyretica were rather diffuse. The increase in the xanthophyll index was the most consistent response to sun conditions, occurring in the three species studied. The responses of soluble UVACs were generally clearer than those of insoluble UVACs, probably because insoluble UVACs are relatively immobilized in the cell wall. These modalities of radiation acclimation were reliably summarized by principal components analysis. Using the most radiation-responsive species in the field (M. polymorpha), we found, under close-to-ambient greenhouse conditions, that sclerophylly and Chl a + b content were only influenced by PAR, F v/F m, and luteolin and apigenin derivatives were only determined by UV, and xanthophyll index was influenced by both radiation types. Thus, responses of bryophytes to radiation can be better interpreted considering the influence of both PAR and UV radiation.

13.
Photochem Photobiol Sci ; 18(2): 400-412, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30608105

RESUMO

We studied the effects of different radiation treatments on the physiology and UV-absorbing compounds of the model liverwort Marchantia polymorpha subsp. ruderalis. Starting from gemmae, samples were exposed to five radiation treatments: low photosynthetically active radiation (PAR), low PAR+ UV-A, low PAR + UV-B, low PAR + UV-A + UV-B, and high PAR. After 35 days, the maximum quantum yield of photosystem II was similar between treatments, which suggested comparable photoinhibition and physiological vitality, also supported by results showing an unchanged chlorophyll a/b ratio and only slight changes in growth. However, the total contents of both chlorophylls and carotenoids decreased in the UV radiation treatments and, more strongly, in the high-PAR samples, suggesting mainly PAR-dependent damage to the photosynthetic pigments. The xanthophyll index (antheraxanthin + zeaxanthin)/(violaxanthin + antheraxanthin + zeaxanthin) was only increased in the high-PAR samples, indicating an increase in photoprotection through nonphotochemical dissipation of the excess energy. The sclerophylly index (the ratio between the thallus dry mass and surface area) was increased in the UV-B-exposed samples, suggesting a UV-induced structural protection. Only the UV-B-exposed samples showed DNA damage. Several apigenin and luteolin derivatives were found in the methanol-soluble vacuolar fraction of the liverwort and p-coumaric and ferulic acids in the methanol-insoluble cell wall-bound fraction. Most individual soluble compounds, the bulk level of soluble compounds, and chalcone synthase expression increased in UV-B-exposed samples, whereas individual insoluble compounds increased in the samples exposed to only PAR. Principal components analysis summarized these responses, showing the strong influence of both UV-B and PAR levels on the physiology and UV protection of the samples.


Assuntos
Marchantia/metabolismo , Marchantia/efeitos da radiação , Fotossíntese/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Metabolismo Energético/efeitos da radiação , Marchantia/fisiologia , Fatores de Tempo , Xantofilas/metabolismo
14.
Behav Res Methods ; 51(3): 1205-1215, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29949069

RESUMO

Sensory experience rating (SER) is a recently developed subjective lexical index that reflects the extent to which a word evokes a sensory and/or perceptual experience in a reader (Juhasz & Yap, 2013; Juhasz, Yap, Dicke, Taylor, & Gullick, 2011). In the present study, SERs for a set of 5,500 Spanish words were collected, which makes this the largest set of norms for SER in the Spanish language to date. Additionally, with the aim of further exploring the implications of this new indicator and its relations with other psycholinguistic variables, a variety of correlational and regression analyses are provided. The results showed that SERs significantly correlated with imageability, age of acquisition, and a number of variables related to perception and emotion. In addition, SERs predicted a significant amount of variance in lexical decision times when other variables were controlled.


Assuntos
Idioma , Adolescente , Adulto , Tomada de Decisões , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicolinguística , Vocabulário , Adulto Jovem
15.
Plant Physiol Biochem ; 134: 137-144, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30037765

RESUMO

To study the potential quick responses to ultraviolet (UV) radiation of bryophyte phenolic compounds, we cultivated two thalloid liverworts, two leafy liverworts, and two mosses under three moderate realistic UV levels in the laboratory for 22 days. At the end of the daylight period on the first and last culture days, we measured the bulk levels and individual contents of phenolic UV-absorbing compounds (UVACs) of each species, differentiating in both cases the UVACs located in the methanol-soluble (mainly vacuolar) and -insoluble (cell wall-bound) fractions (SUVACs and IUVACs, respectively). The bulk levels of SUVACs and IUVACs mostly showed linear or hyperbolic relationships with the UV dose applied. Thirteen flavones (apigenin and luteolin derivatives) and two hydroxycinnamic acids (p-coumaric and ferulic acids) were identified in the soluble and insoluble fractions, respectively. Only two compounds (p-coumaric and ferulic acids) from the insoluble fraction of the leafy liverwort Plagiochila asplenioides showed a significant quick accumulation in response to UV radiation in the first day of culture, whereas six UVACs (mainly soluble apigenin and luteolin derivatives) from different species (mainly liverworts) were significantly accumulated at the end of the culture. In conclusion, the responses of bryophyte UVACs to UV radiation were influenced by the specific compound considered, the fraction in which each UVAC was located, the global or individual way of UVACs quantification, the bryophyte species and evolutionary lineage, and the experimental conditions used. Particularly, SUVACs were more UV-responsive than IUVACs and liverworts than mosses, and responses were not especially quick.


Assuntos
Briófitas/metabolismo , Briófitas/efeitos da radiação , Compartimento Celular , Fenóis/metabolismo , Raios Ultravioleta , Análise de Regressão , Fatores de Tempo
16.
Am J Bot ; 105(6): 996-1008, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29985543

RESUMO

PREMISE OF THE STUDY: Ultraviolet (UV) radiation influences the viability of algal spores and seed-plant pollen depending on the species, the dose, and the wavelength. In bryophytes, one of the dominant groups of plants in many habitats, UV radiation could determine their spore dispersal strategy, and such data are critical for reconstructing the ancestral state in plants and for determining the distribution range and persistence of bryophyte species. METHODS: Spores of four bryophyte species of the moss genus Orthotrichum that were either hygrochastic or xerochastic (spores dispersed under wet or dry conditions, respectively) were exposed to realistic doses of UV radiation under laboratory conditions. Spore viability was evaluated through germination experiments and, for the first time in bryophytes, ultrastructural observations. Given that the UV-B doses used were relatively higher than the UV-A doses, the UV effect was probably due more to UV-B than UV-A wavelengths. KEY RESULTS: All four species reduced their spore germination capacity in a UV dose-dependent manner, concomitantly increasing spore ultrastructural damage (cytoplasmic and plastid alterations). Most spores eventually died when exposed to the highest UV dose. Interestingly, spores of hygrochastic species were much more UV-sensitive than those of xerochastic species. CONCLUSIONS: UV tolerance determines moss spore viability, as indicated by germination capacity and ultrastructural damage, and differs between spores of species with different dispersal strategies. Specifically, the higher UV tolerance of xerochastic spores may enable them to be dispersed to longer distances than hygrochastic spores, thus extending more efficiently the distribution range of the corresponding species.


Assuntos
Bryopsida/efeitos da radiação , Dispersão Vegetal , Esporos/efeitos da radiação , Bryopsida/ultraestrutura , Esporos/ultraestrutura , Raios Ultravioleta
17.
Behav Res Methods ; 50(4): 1632-1644, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29052168

RESUMO

Subjective ratings of perceptual and motor attributes were obtained for a set of 750 concrete concepts in Spanish by requiring scale-based judgments from a sample of university students (N = 539). Following on the work of Amsel, Urbach, and Kutas (2012), the seven attributes were color, motion, sound, smell, taste, graspability, and pain. Normative data based on the obtained ratings are provided as a tool for future investigations. Additionally, the relationships of these attributes to other lexical dimensions (e.g., familiarity, frequency, concreteness) and the factorial organization of concepts around the main components were analyzed. The pattern of results is consistent with prior findings that highlight the relevance of dimensions related to survival as being crucially involved in conceptual processing.


Assuntos
Retroalimentação Sensorial/fisiologia , Julgamento/fisiologia , Idioma , Percepção/fisiologia , Adulto , Cor , Feminino , Força da Mão , Humanos , Masculino , Percepção da Dor , Reconhecimento Psicológico , Olfato , Som , Paladar , Adulto Jovem
18.
J Agric Food Chem ; 64(46): 8722-8734, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27794599

RESUMO

Mature berries of Pinot Noir grapevines were sampled across a latitudinal gradient in Europe, from southern Spain to central Germany. Our aim was to study the influence of latitude-dependent environmental factors on the metabolite composition (mainly phenolic compounds) of berry skins. Solar radiation variables were positively correlated with flavonols and flavanonols and, to a lesser extent, with stilbenes and cinnamic acids. The daily means of global and erythematic UV solar radiation over long periods (bud break-veraison, bud break-harvest, and veraison-harvest), and the doses and daily means in shorter development periods (5-10 days before veraison and harvest) were the variables best correlated with the phenolic profile. The ratio between trihydroxylated and monohydroxylated flavonols, which was positively correlated with antioxidant capacity, was the berry skin variable best correlated with those radiation variables. Total flavanols and total anthocyanins did not show any correlation with radiation variables. Air temperature, degree days, rainfall, and aridity indices showed fewer correlations with metabolite contents than radiation. Moreover, the latter correlations were restricted to the period veraison-harvest, where radiation, temperature, and water availability variables were correlated, making it difficult to separate the possible individual effects of each type of variable. The data show that managing environmental factors, in particular global and UV radiation, through cultural practices during specific development periods, can be useful to promote the synthesis of valuable nutraceuticals and metabolites that influence wine quality.


Assuntos
Vitis/química , Vitis/metabolismo , Altitude , Antocianinas/análise , Antocianinas/metabolismo , Ecossistema , Europa (Continente) , Flavonóis/análise , Flavonóis/metabolismo , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/efeitos da radiação , Polifenóis/análise , Polifenóis/metabolismo , Raios Ultravioleta , Vitis/crescimento & desenvolvimento , Vitis/efeitos da radiação
19.
Plant Physiol Biochem ; 109: 374-386, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27810677

RESUMO

In the present study we assessed the effects of ambient solar UV exclusion on leaf physiology, and leaf and berry skin phenolic composition, of a major grapevine cultivar (Tempranillo) grown under typically Mediterranean field conditions over an entire season. In general, the effects of time were stronger than those of UV radiation. Ambient UV caused a little stressing effect (eustress) on leaf physiology, with decreasing net photosynthesis rates and stomatal conductances. However, it was not accompanied by alterations in Fv/Fm or photosynthetic pigments, and was partially counterbalanced by the UV-induced accumulation of protective flavonols. Consequently, Tempranillo leaves are notably adapted to current UV levels. The responses of berry skin phenolic compounds were diverse, moderate, and mostly transitory. At harvest, the clearest response in UV-exposed berries was again flavonol accumulation, together with a decrease in the flavonol hydroxylation level. Contrarily, responses of anthocyanins, flavanols, stilbenes and hydroxycinnamic derivatives were much more subtle or nonexistent. Kaempferols were the only compounds whose leaf and berry skin contents were correlated, which suggests a mostly different regulation of phenolic metabolism for each organ. Interestingly, the dose of biologically effective UV radiation (UVBE) was correlated with the leaf and berry skin contents of quercetins and kaempferols; relationships were linear except for the exponential relationship between UVBE dose and berry skin kaempferols. This opens management possibilities to modify kaempferol and quercetin contents in grapevine through UV manipulation.


Assuntos
Fenóis/metabolismo , Vitis/metabolismo , Vitis/efeitos da radiação , Frutas/metabolismo , Frutas/efeitos da radiação , Quempferóis/metabolismo , Região do Mediterrâneo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Quercetina/metabolismo , Estações do Ano , Espanha , Luz Solar , Raios Ultravioleta
20.
Behav Res Methods ; 48(4): 1337-1342, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26494650

RESUMO

Many studies have shown that how words are processed in a variety of language-related tasks is affected by their age of acquisition (AoA). Most AoA norms have been collected for nouns, a fact that limits the extent to which verb stimuli can be adequately manipulated and controlled in empirical studies. With the aim of increasing the number of verbs with AoA values in Spanish, 900 college students were recruited to provide subjective estimates for a total of 4,640 infinitive and reflexive forms. An AoA score for each verb was obtained by averaging the responses of the participants, and these norms were included, together with additional quantitative information (standard deviations, ranges, and z scores), in a database that can be downloaded with this article as supplemental materials.


Assuntos
Idioma , Padrões de Referência , Adolescente , Adulto , Fatores Etários , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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