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In this paper, we have performed an in-depth study of the complete set of the satellite DNA (satDNA) families (i.e. the satellitomes) in the genome of two barley species of agronomic value in a breeding framework, H. chilense (H1 and H7 accessions) and H. vulgare (H106 accession), which can be useful tools for studying chromosome associations during meiosis. The study has led to the analysis of a total of 18 satDNA families in H. vulgare, 25 satDNA families in H. chilense (accession H1) and 27 satDNA families in H. chilense (accession H7) that constitute 46 different satDNA families forming 36 homology groups. Our study highlights different important contributions of evolutionary and applied interests. Thus, both barley species show very divergent satDNA profiles, which could be partly explained by the differential effects of domestication versus wildlife. Divergence derives from the differential amplification of different common ancestral satellites and the emergence of new satellites in H. chilense, usually from pre-existing ones but also random sequences. There are also differences between the two H. chilense accessions, which support genetically distinct groups. The fluorescence in situ hybridization (FISH) patterns of some satDNAs yield distinctive genetic markers for the identification of specific H. chilense or H. vulgare chromosomes. Some of the satellites have peculiar structures or are related to transposable elements which provide information about their origin and expansion. Among these, we discuss the existence of different (peri)centromeric satellites that supply this region with some plasticity important for centromere evolution. These peri(centromeric) satDNAs and the set of subtelomeric satDNAs (a total of 38 different families) are analyzed in the framework of breeding as the high diversity found in the subtelomeric regions might support their putative implication in chromosome recognition and pairing during meiosis, a key point in the production of addition/substitution lines and hybrids.
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Cromossomos de Plantas , DNA Satélite , Hordeum , Hibridização in Situ Fluorescente , Hordeum/genética , DNA Satélite/genética , Cromossomos de Plantas/genética , DNA de Plantas/genética , Genoma de Planta/genética , Filogenia , Variação Genética , Meiose/genética , Evolução Molecular , Especificidade da EspécieRESUMO
Adenine metabolism is important for common bean (Phaseolus vulgaris L) productivity since this legume uses ureides derived from the oxidation of purine nucleotides, as their primary nitrogen storage molecules. Purine nucleotides are produced from de novo synthesis or through salvage pathways. Adenine phosphoribosyl transferase (APRT) is the enzyme dedicated to adenine nucleobase salvage for nucleotide synthesis, but it also acts on the inactivation of cytokinin bases. In common bean, the APRT enzyme is encoded by four genes. Gene expression analysis, biochemical properties and subcellular location suggest functional differences among the common bean APRT isoforms. CRISPR/Cas9 targeted downregulation of two of the four PvAPRTs followed by metabolomics and physiological analyses of targeted hairy roots reveals that, although the two proteins have redundant functions, PvAPRT1 mostly participates in the salvage of adenine, whereas PvAPRT5 is the predominant form in the regulation of cytokinin homeostasis and stress responses with a high impact in root and nodule growth.
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The use of adverse effect data from animals as the gold standard in regulatory toxicology has a long tradition dating back to the 1960s. It has also been increasingly criticised, based on both scientific and animal welfare concerns, and yet, animal studies remain the gold standard in most areas of toxicology to this very day. In the 1980s, when the first generation of non-animal methods were evaluated as alternatives to animal testing, it was logical to compare the 'new' data obtained with historical animal data. This worked reasonably well for simple endpoints, such as skin and eye irritation, but became problematic for the more complex systemic endpoints, since in these cases, the in vivo effects are not directly comparable to those observed in in vitro systems. While the need to redefine the gold standard is not new, there is still no consensus on how to do so. We propose a consistent principle that avoids the need for animal reference data, while also ensuring an equivalent or better level of protection. We argue that the gold standard can be redefined, or rather bypassed, by focusing on risk management outcomes rather than the outputs of animal methods. This allows us to more efficiently protect human health and the environment, ensuring the safe use of chemicals while also identifying less hazardous chemicals for use as substitutes. We describe how this might work out for two main contexts of use: classification and labelling, and risk assessment. This has implications for the implementation of the EU Commission Roadmap toward the phasing out of animal testing in chemical safety assessments.
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BACKGROUND AND AIMS: Durum wheat, Triticum turgidum, and bread wheat, Triticum aestivum, are two allopolyploid species of very recent origin that have been subjected to intense selection programs during the thousands of years they have been cultivated. In this paper, we study the durum wheat satellitome and establish a comparative analysis with the previously published bread wheat satellitome. METHODS: We revealed the durum wheat satellitome using the satMiner protocol which is based on consecutive rounds of clustering of Illumina reads by RepeatExplorer2, and estimated abundance and variation for each identified satDNA with RepeatMasker v4.0.5. We have also performed a deep satDNA families characterization including chromosomal location by Fluorescence In Situ Hybridization (FISH) in durum wheat and its comparison with FISH patterns in bread wheat. Basic Local Alignment Search Tool (BLAST®) was used for trailing each satDNA in the assembly of durum wheat genome through NCBI's Genome Data Viewer (GDW) and the genome assemblies of both species were compared. Sequence divergence and consensus turnover rate (CTR) between homologous satDNA families of durum and bread wheat were estimated using MEGA11. KEY RESULTS: This study reveals that in an exceedingly short period, significant qualitative and quantitative changes have occurred in the set of satellite DNAs (satDNAs) of both species, with expansions/contractions of the number of repeats and the loci per satellite, different in each species, and a high rate of sequence change for most of these satellites, in addition to the emergence/loss of satDNAs not shared between the two species analysed. These evolutionary changes in satDNA are common between species but what is truly remarkable and novel about this study is that these processes have taken place in less than the last ~8000 years separating the two species, indicating an accelerated evolution of their satDNAs. CONCLUSIONS: These results, together with the relationship of many of these satellites with transposable elements and the polymorphisms they generate at the level of centromeres and subtelomeric regions of their chromosomes, are analysed and discussed in the context of the evolutionary origin of these species and the selection pressure exerted by man throughout the history of their cultivation.
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BACKGROUND AND AIMS: Baseline cardiovascular toxicity risk stratification is critical in cardio-oncology. The Heart Failure Association (HFA) and International Cardio-Oncology Society (ICOS) score aims to assess this risk but lacks real-life validation. This study validates the HFA-ICOS score for anthracycline-induced cardiovascular toxicity. METHODS: Anthracycline-treated patients in the CARDIOTOX registry (NCT02039622) were stratified by the HFA-ICOS score. The primary endpoint was symptomatic or moderate to severe asymptomatic cancer therapy-related cardiac dysfunction (CTRCD), with all-cause mortality and cardiovascular mortality as secondary endpoints. RESULTS: The analysis included 1066 patients (mean age 54 ± 14 years; 81.9% women; 24.5% ≥65 years). According to the HFA-ICOS criteria, 571 patients (53.6%) were classified as low risk, 333 (31.2%) as moderate risk, 152 (14.3%) as high risk, and 10 (0.9%) as very high risk. Median follow-up was 54.8 months (interquartile range 24.6-81.8). A total of 197 patients (18.4%) died, and 718 (67.3%) developed CTRCD (symptomatic: n = 45; moderate to severe asymptomatic: n = 24; and mild asymptomatic: n = 649). Incidence rates of symptomatic or moderate to severe symptomatic CTRCD and all-cause mortality significantly increased with HFA-ICOS score [hazard ratio 28.74, 95% confidence interval (CI) 9.33-88.5; P < .001, and hazard ratio 7.43, 95% CI 3.21-17.2; P < .001) for very high-risk patients. The predictive model demonstrated good calibration (Brier score 0.04, 95% CI 0.03-0.05) and discrimination (area under the curve 0.78, 95% CI 0.70-0.82; Uno's C-statistic 0.78, 95% CI 0.71-0.84) for predicting symptomatic or severe/moderate asymptomatic CTRCD at 12 months. CONCLUSIONS: The HFA-ICOS score effectively categorizes patients by cardiovascular toxicity risk and demonstrates strong predictive ability for high-risk anthracycline-related cardiovascular toxicity and all-cause mortality.
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The use of wild species as a source of genetic variability is a valued tool in the framework of crop breeding. Hordeum chilense Roem. et Schult is a wild barley species that can be a useful genetic donor for sustainable wheat breeding which carries genes conferring resistance to some diseases or increasing grain quality, among others. Septoria tritici blotch (STB), caused by the Zymoseptoria tritici fungus, is one of the most important wheat diseases worldwide, affecting both bread and durum wheat and having a high economic impact. Resistance to STB has been previously described in H. chilense chromosome 4Hch. In this study, we have developed introgression lines for H. chilense chromosome 4Hch in durum wheat using interspecific crosses, advanced backcrosses, and consecutive selfing strategies. Alien H. chilense chromosome segments have been reduced in size by genetic crosses between H. chilense disomic substitution lines in durum wheat and durum wheat lines carrying the Ph1 deletion. Hordeum chilense genetic introgressions were identified in the wheat background through several plant generations by fluorescence in situ hybridisation (FISH) and simple sequence repeat (SSR) markers. An STB infection analysis has also been developed to assess STB resistance to a specific H. chilense chromosome region. The development of these H. chilense introgression lines with moderate to high resistance to STB represents an important advance in the framework of durum breeding and can be a valuable tool for plant breeders.
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Understanding the interactions in hybrid systems based on graphene and functional oxides is crucial to the applicability of graphene in real devices. Here, we present a study of the structural defects occurring on graphene during the early stages of the growth of CoO, tailored by the electronic coupling between graphene and the substrate in which it is supported: as received pristine graphene on polycrystalline copper (coupled), cleaned in ultra-high vacuum conditions to remove oxygen contamination, and graphene transferred to SiO2/Si substrates (decoupled). The CoO growth was performed at room temperature by thermal evaporation of metallic Co under a molecular oxygen atmosphere, and the early stages of the growth were investigated. On the decoupled G/SiO2/Si samples, with an initial low crystalline quality of graphene, the formation of a CoO wetting layer is observed, identifying the Stranski-Krastanov growth mode. In contrast, on coupled G/Cu samples, the Volmer-Weber growth mechanism is observed. In both sets of samples, the oxidation of graphene is low during the early stages of growth, increasing for the larger coverages. Furthermore, structural defects are developed in the graphene lattice on both substrates during the growth of CoO, which is significantly higher on decoupled G/SiO2/Si samples mainly for higher CoO coverages. When approaching the full coverage on both substrates, the CoO islands coalesce to form a continuous CoO layer with strip-like structures with diameters ranging between 70 and 150 nm.
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BACKGROUND: To infer a reliable SARS-CoV-2 antibody protection level from a serological test, an appropriate quantitative threshold and solid equivalence across serological tests are needed. Additionally, tests should show a solid correlation with neutralising assays and with the protection observed in large population cohorts even against emerging variants. OBJECTIVES: We studied convalescent and vaccinated populations using 11 commercial antibody assays. Results were compared to evaluate discrepancies across tests. Neutralisation capacity was measured in a subset of the samples with a lentiviral-based assay. METHODS: Serum from convalescent (n = 121) and vaccinated individuals (n = 471, 260 with Comirnaty, 110 with Spikevax, and 96 with Vaxzevria) was assessed using 11 different assays, including two from Abbott, Euroimmun, Liaison, Roche, and Vircell, and one from Siemens. A spike protein-lentiviral vector with a fluorescent reporter was used for neutralisation assay of serum from convalescent (n = 26) and vaccinated (n = 39) individuals. RESULTS: Positivity ranged between 81.3 and 94.3% after infection and 99.4 and 99.7% after vaccination, depending on the assay. Both cohorts showed a high level of qualitative agreement across tests (Fleiss' kappa = 0.598 and 0.719 for convalescent and vaccinated respectively). Spikevax vaccine recipients showed the highest level of antibodies in all tests. Effectiveness of each test predicting SARS-CoV-2 neutralising capacity depended on assay type and target, with CLIA and anti-S being more effective than ELISA and anti-N assays, respectively. CONCLUSIONS: High-throughput immunoassays are good predictors of neutralising capacity. Updated targets and better standardisation would be required to find an effective correlate of protection, especially to account for antibodies against new variants.
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Thin films of lithium spinel ferrite, LiFe5O8, have attracted much scientific attention because of their potential for efficient excitation, the manipulation and propagation of spin currents due to their insulating character, high-saturation magnetization, and Curie temperature, as well as their ultra-low damping value. In addition, LiFe5O8 is currently one of the most interesting materials in terms of developing spintronic devices based on the ionic control of magnetism, for which it is crucial to control the lithium's atomic content. In this work, we demonstrate that dual ion beam sputtering is a suitable technique to tailor the lithium content of thin films of lithium ferrite (LFO) by using the different energies of the assisting ion beam formed by Ar+ and O2+ ions during the growth process. Without assistance, a disordered rock-salt LFO phase (i.e., LiFeO2) can be identified as the principal phase. Under beam assistance, highly out-of-plane-oriented (111) thin LFO films have been obtained on (0001) Al2O3 substrates with a disordered spinel structure as the main phase and with lithium concentrations higher and lower than the stoichiometric spinel phase, i.e., LiFe5O8. After post-annealing of the films at 1025 K, a highly ordered ferromagnetic spinel LFO phase was found when the lithium concentration was higher than the stoichiometric value. With lower lithium contents, the antiferromagnetic hematite (α-Fe2O3) phase emerged and coexisted in films with the ferromagnetic LixFe6-xO8. These results open up the possibility of controlling the properties of thin lithium ferrite-based films to enable their use in advanced spintronic devices.
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In bread wheat (Triticum aestivum L.), chromosome associations during meiosis are extremely regulated and initiate at the telomeres and subtelomeres, which are enriched in satellite DNA (satDNA). We present the study and characterization of the bread wheat satellitome to shed light on the molecular organization of wheat subtelomeres. Our results revealed that the 2.53% of bread wheat genome is composed by satDNA and subtelomeres are particularly enriched in such DNA sequences. Thirty-four satellite DNA (21 for the first time in this work) have been identified, analyzed and cytogenetically validated. Many of the satDNAs were specifically found at particular subtelomeric chromosome regions revealing the asymmetry in subtelomere organisation among the wheat subgenomes, which might play a role in proper homologous recognition and pairing during meiosis. An integrated physical map of the wheat satellitome was also constructed. To the best of our knowledge, our results show that the combination of both cytogenetics and genome research allowed the first comprehensive analysis of the wheat satellitome, shedding light on the complex wheat genome organization, especially on the polymorphic nature of subtelomeres and their putative implication in chromosome recognition and pairing during meiosis.
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Genoma de Planta , Triticum , Triticum/genética , DNA Satélite , Pão , Sequência de BasesRESUMO
Rice (Oryza sativa L.) is a very important cereal worldwide, since it is the staple food for more than half of the world's population. Iron (Fe) deficiency is among the most important agronomical concerns in calcareous soils where rice plants may suffer from this deficiency. Current production systems are based on the use of high-yielding varieties and the application of large quantities of agrochemicals, which can cause major environmental problems. The use of beneficial rhizosphere microorganisms is considered a relevant sustainable alternative to synthetic fertilizers. The main goal of this study was to determine the ability of the nonpathogenic strain Fusarium oxysporum FO12 to induce Fe-deficiency responses in rice plants and its effects on plant growth and Fe chlorosis. Experiments were carried out under hydroponic system conditions. Our results show that the root inoculation of rice plants with FO12 promotes the production of phytosiderophores and plant growth while reducing Fe chlorosis symptoms after several days of cultivation. Moreover, Fe-related genes are upregulated by FO12 at certain times in inoculated plants regardless of Fe conditions. This microorganism also colonizes root cortical tissues. In conclusion, FO12 enhances Fe-deficiency responses in rice plants, achieves growth promotion, and reduces Fe chlorosis symptoms.
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Chemical regulatory authorities around the world require systemic toxicity data from acute exposures via the oral, dermal, and inhalation routes for human health risk assessment. To identify opportunities for regulatory uses of non-animal replacements for these tests, we reviewed acute systemic toxicity testing requirements for jurisdictions that participate in the International Cooperation on Alternative Test Methods (ICATM): Brazil, Canada, China, the European Union, Japan, South Korea, Taiwan, and the USA. The chemical sectors included in our review of each jurisdiction were cosmetics, consumer products, industrial chemicals, pharmaceuticals, medical devices, and pesticides. We found acute systemic toxicity data were most often required for hazard assessment, classification, and labeling, and to a lesser extent quantitative risk assessment. Where animal methods were required, animal reduction methods were typically recommended. For many jurisdictions and chemical sectors, non-animal alternatives are not accepted, but several jurisdictions provide guidance to support the use of test waivers to reduce animal use for specific applications. An understanding of international regulatory requirements for acute systemic toxicity testing will inform ICATM's strategy for the development, acceptance, and implementation of non-animal alternatives to assess the health hazards and risks associated with acute toxicity.
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Carbon nanohorns have been non-covalently functionalized with two different benzothiadiazoloquinoxalines prepared via Stille cross-coupling reactions under solvent-free conditions and microwave irradiation. The close interactions between these organic molecules and the nanostructures resulted in a prominent Raman enhancement, which makes them attractive candidates for multiple applications. A complete experimental physico-chemical characterization has been combined with in silico studies to understand these phenomena. The processability of the hybrids was exploited to prepare homogeneous films on substrates with different natures.
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A new series of donor-acceptor-donor (D-A-D) structures derived from arylethynyl 1H-benzo[d]imidazole was synthesized and processed into single crystals with the goal of testing such crystals' ability to act as optical waveguides. Some crystals displayed luminescence in the 550-600 nm range and optical waveguiding behavior with optical loss coefficients around 10-2 dB/µm, which indicated a notable light transport. The crystalline structure, confirmed by X-ray diffraction, contains internal channels that are important for light propagation, as we previously reported. The combination of a 1D assembly, a single crystal structure, and notable light emission properties with low losses from self-absorption made 1H-benzo[d]imidazole derivatives appealing compounds for optical waveguide applications.
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A series of donor-π-acceptor-π-donor (D-π-A-π-D) compounds based on naphthalendiimide (NDI) and perylenediimide (PDI) central cores combined with triphenylamine and phenylcarbazole donor groups have been synthesized, characterized and tested in top-contact/bottom gate organic field-effect transistors (OFETs). The results showed high electron mobilities, up to 0.3â cm2 V-1 s-1 , in the case of NDI derivatives and moderate values of around 10-3 â cm2 V-1 s-1 for PDI-based semiconductors. Quantum chemical calculations were performed in order to support the experimental data. The results suggest that adequate molecular characteristics and larger crystalline domains in NDI vs. PDI semiconducting films may be the reasons behind the enhanced electrical properties of NDI derivatives. Furthermore, when the lateral donor substituents are triphenylamine groups, the mobilities were slightly higher in comparison to phenylcarbazole donor groups due to an improved electron-donating character. Other characterization techniques, such as AFM, X-ray diffraction or spectroelectrochemistry, among others, have been performed to analyze supramolecular order, charge carriers' nature and stability, parameters closely related to charge transport characteristics.
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Recently, there have been reports of what could be a new lymphoproliferative entity: breast implant-associated Epstein-Barr virus positive (EBV+) diffuse large B-cell lymphoma (EBV+ BIA-DLBCL). The new World Health Organization classification has categorized it as fibrin-associated large B-cell lymphomas (FA-LBCLs); therefore, it could be referred to as breast implant-associated fibrin-associated large B-cell lymphomas (BIA-FA-LBCLs). Although the association between breast implants and lymphomas has been known since the mid-1990s, it has been almost exclusively breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). Here, we describe the first case of BIA-FA-LBCL at our center, with a literature review of the clinical features, diagnosis and treatment approach of this lymphoma. We also explore the differential diagnosis of BIA-FA-LBCL, highlighting the diagnostic challenges and the reasons that have led these lymphomas to being labeled as a new face of FA-LBCL.
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Background: Sinusoidal obstructive syndrome (SOS) is a potentially fatal complication secondary to hematopoietic stem cell transplant (HSCT) conditioning. Endothelial damage plasma biomarkers such as plasminogen activator inhibitor-1 (PAI-1), hyaluronic acid (HA), and vascular adhesion molecule-1 (VCAM1) represent potential diagnostic tools for SOS. Methods: We prospectively collected serial citrated blood samples (baseline, day 0, day 7, and day 14) in all adult patients undergoing HSCT at La Paz Hospital, Madrid. Samples were later analyzed by ELISA (enzyme-linked immunosorbent assay) for HA, VCAM1, and PAI-1 concentrations. Results: During sixteen months, we prospectively recruited 47 patients. Seven patients (14%) were diagnosed with SOS according to the EBMT criteria for SOS/VOD diagnosis and received treatment with defibrotide. Our study showed a statistically significant elevation of HA on day 7 in SOS patients, preceding clinical SOS diagnosis, with a sensitivity of 100%. Furthermore, we observed a significant increase of HA and VCAM1 levels on day 14. Regarding risk factors, we observed a statistically significant association between SOS diagnosis and the fact that patients received 3 or more previous lines of treatment before HSCT. Conclusions: The early significant increase in HA levels observed opens the door to a noninvasive peripheral blood test which could have the potential to improve diagnosis and facilitate prophylactic and therapeutic management of SOS before clinical/histological damage is established.
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Transplante de Células-Tronco Hematopoéticas , Hepatopatia Veno-Oclusiva , Adulto , Humanos , Hepatopatia Veno-Oclusiva/diagnóstico , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/tratamento farmacológico , Ácido Hialurônico , Inibidor 1 de Ativador de Plasminogênio , Polidesoxirribonucleotídeos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Molécula 1 de Adesão de Célula VascularRESUMO
MAIN CONCLUSION: FO12 strain enhances Fe deficiency responses in cucumber plants, probably through the production of ethylene and NO in the subapical regions of the roots. Rhizosphere microorganisms can elicit induced systemic resistance (ISR) in plants. This type of resistance involves complex mechanisms that confer protection to the plant against pathogen attack. Additionally, it has been reported by several studies that ISR and Fe deficiency responses are modulated by common pathways, involving some phytohormones and signaling molecules, like ethylene and nitric oxide (NO). The aim of this study was to determine whether the nonpathogenic strain of Fusarium oxysporum FO12 can induce Fe deficiency responses in cucumber (Cucumis sativus L.) plants. Our results demonstrate that the root inoculation of cucumber plants with the FO12 strain promotes plant growth after several days of cultivation, as well as rhizosphere acidification and enhancement of ferric reductase activity. Moreover, Fe-related genes, such as FRO1, IRT1 and HA1, are upregulated at certain times after FO12 inoculation either upon Fe-deficiency or Fe-sufficient conditions. Furthermore, it has been found that this fungus colonizes root cortical tissues, promoting the upregulation of ethylene synthesis genes and NO production in the root subapical regions. To better understand the effects of the FO12 strain on field conditions, cucumber plants were inoculated and cultivated in a calcareous soil under greenhouse conditions. The results obtained show a modification of some physiological parameters in the inoculated plants, such as flowering and reduction of tissue necrosis. Overall, the results suggest that the FO12 strain could have a great potential as a Fe biofertilizer and biostimulant.
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Cucumis sativus , Fusarium , Cucumis sativus/genética , Raízes de Plantas/metabolismo , Ferro/metabolismo , Etilenos/metabolismoRESUMO
PURPOSE: Though the frequency of gesture use by infants has been related to the development of different language abilities in the initial stages of language acquisition, less is known about whether this frequency (or "gesture rate") continues to correlate with language measures in later stages of language acquisition, or whether the relation to language skills also depends on the accuracy with which such gestures are produced (or reproduced). This study sets out to explore whether preschoolers' narrative abilities are related to these two variables, namely, gesture rate and gesture accuracy. METHOD: A total of 31 typically developing 3- to 4-year-old children participated in a multimodal imitation task, a context-based gesture elicitation task, and a narrative retelling task. RESULTS: Results showed that there was a significant positive correlation between the children's narrative scores and their gesture accuracy scores, whereas higher rates of gesture use did not correlate with higher levels of narrative skill. Further multimodal regression analysis confirmed that gesture accuracy was a positive predictor of narrative performance, and moreover, showed that gesture rate was a negative predictor. CONCLUSIONS: The fact that both gesture accuracy and gesture rate are strongly and differently linked to oral language abilities supports the claim that language and gesture are highly complex systems, and that complementary measures of gesture performance can help us assess with greater granularity the relationship between gesture and language development. These findings highlight the need to use gesture during clinical assessments as an informative indicator of language development and suggest that future research should further investigate the value of multimodal programs in the treatment of language and communication disorders.
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Transtornos da Comunicação , Gestos , Lactente , Humanos , Pré-Escolar , Desenvolvimento da Linguagem , Idioma , AptidãoRESUMO
PURPOSE: This study aims to analyze the development of gesture-speech temporal alignment patterns in children's narrative speech from a longitudinal perspective and, specifically, the potential differences between different gesture types, namely, gestures that imagistically portray or refer to semantic content in speech (i.e., referential gestures) and those that lack semantic content (i.e., non-referential gestures). METHOD: This study uses an audiovisual corpus of narrative productions (n = 332) from 83 children (43 girls, 40 boys) who participated in a narrative retelling task at two time points in development (at 5-6 and 7-9 years of age). The 332 narratives were coded for both manual co-speech gesture types and prosody. Gestural annotations included gesture phasing (i.e., preparation, stroke, hold, and recovery) and gesture types (in terms of referentiality, i.e., referential and non-referential), whereas prosodic annotations included pitch-accented syllables. RESULTS: Results revealed that by ages 5-6 years, children already temporally aligned the stroke of both referential and non-referential gestures with pitch-accented syllables, showing no significant differences between these two gesture types. CONCLUSIONS: The results of the present study contribute to the view that both referential and non-referential gestures are aligned with pitch accentuation, and therefore, this is not only a characteristic of non-referential gestures. Our results also add support to McNeill's phonological synchronization rule from a developmental perspective and indirectly back up recent theories about the biomechanics of gesture-speech alignment, suggesting that this is an inherent ability of oral communication.