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1.
J Exp Child Psychol ; 244: 105961, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38776633

RESUMO

Given the increasing prevalence of touchscreen devices that are intended for educational purposes, this study explored children's transfer of learning from touchscreen media compared with video and offline face-to-face learning. A total of 76 5- and 6-year-old Chinese kindergarten children (M = 68.21 months, SD = 3.57, range = 62-76; 30 boys and 46 girls) were randomly assigned to learn eight Chinese characters using a touchscreen-based app, using a video, or through face-to-face interaction. Learning was measured via the recall task scores, recognition task scores, recall efficiency, and recognition efficiency. The results revealed that children's recall and recognition task scores improved when learning took place using the touchscreen or face-to-face interaction. Children's recall efficiency and recognition efficiency were strongest in the face-to-face condition, followed by the touchscreen condition and then the video condition. The effects of instructional format on children's recall and recognition scores and recall efficiency were moderated by age; younger children's recall and recognition scores in the face-to-face condition and the touchscreen condition were significantly higher than in the video condition, yet older children's recall and recognition scores did not differ between conditions. However, for recall efficiency, younger children's recall efficiency in the face-to-face condition and the touchscreen condition was significantly higher than in the video condition; older children's recall efficiency in the face-to-face condition was higher than in both the touchscreen condition and the video condition. In conclusion, both face-to-face interaction and a touchscreen-based app were helpful ways for children to learn Chinese characters compared with video, but face-to-face learning showed advantages over touchscreen learning in recall efficiency for older children.


Assuntos
Rememoração Mental , Aplicativos Móveis , Humanos , Masculino , Feminino , Criança , Pré-Escolar , China , Aprendizagem , Reconhecimento Psicológico , Transferência de Experiência , Gravação em Vídeo
2.
Proc Natl Acad Sci U S A ; 121(23): e2320388121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38805284

RESUMO

Essential for reactive oxygen species (EROS) protein is a recently identified molecular chaperone of NOX2 (gp91phox), the catalytic subunit of phagocyte NADPH oxidase. Deficiency in EROS is a recently identified cause for chronic granulomatous disease, a genetic disorder with recurrent bacterial and fungal infections. Here, we report a cryo-EM structure of the EROS-NOX2-p22phox heterotrimeric complex at an overall resolution of 3.56Å. EROS and p22phox are situated on the opposite sides of NOX2, and there is no direct contact between them. EROS associates with NOX2 through two antiparallel transmembrane (TM) α-helices and multiple ß-strands that form hydrogen bonds with the cytoplasmic domain of NOX2. EROS binding induces a 79° upward bend of TM2 and a 48° backward rotation of the lower part of TM6 in NOX2, resulting in an increase in the distance between the two hemes and a shift of the binding site for flavin adenine dinucleotide (FAD). These conformational changes are expected to compromise superoxide production by NOX2, suggesting that the EROS-bound NOX2 is in a protected state against activation. Phorbol myristate acetate, an activator of NOX2 in vitro, is able to induce dissociation of NOX2 from EROS with concurrent increase in FAD binding and superoxide production in a transfected COS-7 model. In differentiated neutrophil-like HL-60, the majority of NOX2 on the cell surface is dissociated with EROS. Further studies are required to delineate how EROS dissociates from NOX2 during its transport to cell surface, which may be a potential mechanism for regulation of NOX2 activation.


Assuntos
Microscopia Crioeletrônica , NADPH Oxidase 2 , NADPH Oxidases , Fagócitos , Humanos , NADPH Oxidase 2/metabolismo , NADPH Oxidase 2/genética , NADPH Oxidase 2/química , Fagócitos/metabolismo , NADPH Oxidases/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/química , Ligação Proteica , Sítios de Ligação , Doença Granulomatosa Crônica/metabolismo , Doença Granulomatosa Crônica/genética , Modelos Moleculares , Espécies Reativas de Oxigênio/metabolismo
3.
Br J Educ Psychol ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38458817

RESUMO

BACKGROUND: Although adding embodied instructors on the screen is considered an effective way to improve online multimedia learning, its effectiveness is still controversial. The level of realism of embodied on-screen instructors may be an influencing factor, but it is unclear how it affects multimedia learning. AIMS: We explored whether and how embodied on-screen instructors rendered with different levels of realism in multimedia lessons affect learning process and learning outcomes. SAMPLES: We recruited 125 college students as participants. METHODS: Students learned about neural transmission in an online multimedia lesson that included a real human, cartoon human, cartoon animal or no instructor. RESULTS: Students learning with cartoon human or cartoon animal instructors tended to fixate more on the relevant portions of the screen and performed better on retention and transfer tests than no instructor group. The real human group fixated more on the instructor, fixated less on the relevant portion of the screen and performed worse on a retention test in comparison to the cartoon human group. Fixation time on the instructor fully mediated the relationship between instructor realism and retention score. CONCLUSIONS: The addition of embodied on-screen instructors can promote multimedia learning, but the promotion effect would be better if the embodied instructor was a cartoon animal or cartoon human rather than a real human. This suggests an important boundary condition in which less realism of on-screen embodied instructors produces better learning processes and outcomes.

5.
J Exp Child Psychol ; 233: 105680, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37121196

RESUMO

Electronic storybooks are increasingly popular with preschoolers. The purpose of our research was to investigate the effects of interactive and multimedia features in electronic storybooks on preschoolers' learning. We assigned 4- to 6-year-old children to different reading conditions in two experiments. Children were required to complete tests for learning outcomes and answer questions about the reading experience. In Experiment 1, children in the interactive (self-paced) group needed to turn the pages by a button on the page, whereas the pages were turned automatically in the non-interactive (system-controlled) group. We found that children in the system-controlled condition performed better in inference making than children in the self-paced condition. In Experiment 2, we used a 2 (Animation: present or non-present) × 2 (Background Music: present or non-present) between-participants design. We found that children's scores of learning and interest in groups with animations were higher than those in groups without animations. This research suggests that electronic books with animations congruent with the learning content promote learning for both adults and young children. Thus, we offer suggestions for designers of electronic books. Moreover, the study provides implications for educators and parents, and we suggest that multi-featured electronic storybooks for preschoolers should be carefully selected.


Assuntos
Multimídia , Música , Adulto , Humanos , Criança , Pré-Escolar , Livros , Leitura
6.
Comput Math Methods Med ; 2022: 3417005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844439

RESUMO

Objective: Meta-analysis is used to analyze the treatment of early glottic laryngeal carcinoma by cryogenic plasma radiofrequency ablation combined with CO2 laser surgery. Methods: Retrieval of PubMed, Embase, Medline, VIP, Wanfang, and CNKI databases using a computer. The retrieval period is from the creation of the database until August 31, 2021. References to the included literature were also searched at the same time. According to the inclusion and exclusion criteria, literatures are screened independently, relevant data were extracted, and meta-analysis was conducted. Results: Recurrence rates are reported in seven literatures. In interstudy heterogeneity test: P = 0.624, I 2 = 0%, fixed effect model analysis shows that there is no significant difference in recurrence rate between low temperature plasma radiofrequency ablation and CO2 laser ablation (OR = 0.80, 95% CI (0.35, 1.29), P = 0.371). Intraoperative blood loss is reported in 5 literatures, and heterogeneity test of each study is as follows: P = 0.03, I 2 = 67%. Low temperature plasma radiofrequency ablation results in more intraoperative blood loss than CO2 laser ablation (SMD = -0.71, 95% CI (0.08, 0.82), P = 0.01). There are five reports on postoperative pain in two treatments: P = 0.04, I 2 = 64%. There is no significant difference in postoperative pain between low temperature plasma radiofrequency ablation and CO2 laser ablation (SMD = -0.21, 95% CI (-0.44, 0.10), P = 0.134). Operative time is reported in nine articles: P < 0.01, I 2 = 95%. The operative time of low temperature plasma radiofrequency ablation is significantly shorter than CO2 laser ablation (SMD = -2.38, 95% CI (-3.91, -1.62), P < 0.01). There are two reports on postoperative mucosal recovery: P = 0.328, I 2 = 2%. Low temperature plasma radiofrequency ablation was significantly better than CO2 laser ablation in postoperative mucosal recovery (OR = 5.49, 95% CI (2.36, 10.18), P < 0.01). Conclusion: Low temperature plasma radiofrequency ablation is superior to CO2 laser surgery in the treatment of early glottic laryngeal carcinoma in terms of operative time and postoperative mucosal recovery. Low-temperature plasma radiofrequency ablation, on the other hand, results in higher intraoperative blood loss, with no discernible difference in recurrence rate or postoperative pain severity between the two treatments.


Assuntos
Carcinoma , Ablação por Cateter , Neoplasias Laríngeas , Terapia a Laser , Perda Sanguínea Cirúrgica , Dióxido de Carbono , Carcinoma/cirurgia , Humanos , Neoplasias Laríngeas/cirurgia , Terapia a Laser/métodos , Dor Pós-Operatória/cirurgia , Temperatura , Resultado do Tratamento
7.
Cell Death Discov ; 8(1): 87, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35220404

RESUMO

The hippocampal neurogenesis occurs constitutively throughout adulthood in mammalian species, but declines with age. In this study, we overtly found that the neuroblast proliferation and differentiation in the subgranular zone and the maturation into fully functional and integrated neurons in the granule-cell layer in young gerbils following cerebral ischemia/reperfusion was much more than those in old gerbils. The neurological function and cognitive and memory-function rehabilitation in the young gerbils improved faster than those in the old one. These results demonstrated that, during long term after cerebral ischemia/reperfusion, the ability of neurogenesis and recovery of nerve function in young animals were significantly higher than that in the old animals. We found that, after 14- and 28-day cerebral ischemia/reperfusion, the phosphorylation of MEK1/2, ERK1/2, p90RSK, and MSK1/2 protein levels in the hippocampus of young gerbils was significantly much higher than that of old gerbils. The levels of autophagy-related proteins, including Beclin-1, Atg3, Atg5, and LC3 in the hippocampus were effectively maintained and elevated at 28 days after cerebral ischemia/reperfusion in the young gerbils compared with those in the old gerbils. These results indicated that an increase or maintenance of the phosphorylation of ERK1/2 signal pathway and autophagy-related proteins was closely associated with the neuroblast proliferation and differentiation and the process of maturation into neurons. Further, we proved that neuroblast proliferation and differentiation in the dentate gyrus and cognitive function were significantly reversed in young cerebral ischemic gerbils by administering the ERK inhibitor (U0126) and autophagy inhibitor (3MA). In brief, following experimental young ischemic stroke, the long-term promotion of the neurogenesis in the young gerbil's hippocampal dentate gyrus by upregulating the phosphorylation of ERK signaling pathway and maintaining autophagy-related protein levels, it overtly improved the neurological function and cognitive and memory function.

8.
Br J Dev Psychol ; 40(2): 320-333, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35040502

RESUMO

Prior studies have shown that children can select and evaluate information based on the previous accuracy of an informant. The current study examines how 5- to 6-year-old kindergarteners (N = 46) and 7- to 8-year-old second-graders (N = 48) in China judge scientific information provided by the internet or a teacher, and how a source's history of inaccuracy influences participants' judgments. When lacking explicit information about previous accuracy, neither younger children nor older children showed differential trust in the internet or a teacher. After observing the internet providing inaccurate information, children in both age groups decreased their trust in statements from the internet. When the teacher was consistently inaccurate, children in both age groups also showed reduced preference for the teacher's statements. These findings demonstrate that 5- to 8-year-old children take into account history of inaccuracy when deciding whether to request or endorse information from the internet or a teacher.


Assuntos
Julgamento , Confiança , Adolescente , Criança , Pré-Escolar , China , Humanos , Internet
9.
Appetite ; 167: 105649, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34400223

RESUMO

Young children learn about the properties of foods, such as taste and healthiness, from others. By using selective trust tasks in which a familiar cartoon character and an unfamiliar informant provided different testimony about food safety, this study examined how an informant's familiarity affected 4- to 6-year-old children's selective social learning about food safety. In Experiment 1, when judging the safety of foods from the familiar cartoon character and the unfamiliar character, children across all age groups showed a preference for asking the familiar character for information. For endorse questions, 4- and 5-year-olds did not consistently accept or reject either character's statements, while 6-year-olds endorsed the unfamiliar cartoon character's statements more often than the familiar character's statements. In Experiment 2, when the unfamiliar informant was a real adult instead of a fictional cartoon character, children sought out information from the familiar character more often than from the adult, and they did not differentially endorse statements by either informant. Moreover, children who had less advanced theory of mind skills and who viewed cartoon characters as more real were more likely to ask the cartoon character. These results suggest that although children prefer to obtain information from familiar characters, they accept information about food safety from multiple kinds of sources and their social-cognitive skills play a role in their decisions.


Assuntos
Preferências Alimentares , Reconhecimento Psicológico , Adulto , Criança , Pré-Escolar , Alimentos , Humanos , Paladar , Confiança
10.
Biomed Res Int ; 2021: 3642463, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33542919

RESUMO

Type 2 diabetes mellitus (T2DM) is a common chronic metabolic disease. Accumulating evidence has demonstrated that nonalcoholic fatty liver disease (NAFLD) shares common typical features with T2DM, and they affect each other extensively. Thus, NAFLD has emerged as a novel target for T2DM prevention and care. Although Corni Fructus (CF) and its extracts have a therapeutic effect on T2DM, its effects and mechanisms on T2DM with NAFLD are far from elucidated. In this study, a mouse model of T2DM with NAFLD complication was established in ICR mice by feeding a high-fat, high-sugar (HFHS) diet and intraperitoneally injecting with a low dose of streptozotocin (STZ). Then, the effects of iridoid glycosides (IG) extracted from CF on this mouse model were investigated. We found that 4-week IG administration remarkably alleviated hyperglycemia and insulin resistance and significantly reduced inflammation, oxidative stress, and fat accumulation in the liver of T2DM with NAFLD mice. Further studies showed that IG inhibited the NF-κB but enhanced the PI3K-AKT signaling pathway. In summary, these results indicated that the IG from CF has potential therapeutic effects on T2DM with NAFLD.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Inflamação/prevenção & controle , Glicosídeos Iridoides/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Cornus/química , Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Inflamação/etiologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/fisiologia , Substâncias Protetoras/farmacologia , Transdução de Sinais
11.
J Ethnopharmacol ; 272: 113923, 2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-33617968

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tanshinone-Ⅰ (TSNⅠ), a member of the mainly active components of Salvia miltiorrhiza Bunge (Dan Shen), which is widely used for the treatment for modern clinical diseases including cardiovascular and cerebrovascular diseases, has been reported to show the properties of anti-oxidation, anti-inflammation, neuroprotection and other pharmacological actions. However, whether TSNⅠ can improve neuron survival and neurological function against transient focal cerebral ischemia (tMCAO) in mice is still a blank field. AIM OF THE STUDY: This study aims to investigate the neuroprotective effects of TSNⅠ on ischemic stroke (IS) induced by tMCAO in mice and explore the potential mechanism of TSNⅠ against IS by combining network pharmacology approach and experimental verification. MATERIALS AND METHODS: In this study, the pivotal candidate targets of TSNⅠ against IS were screened by network pharmacology firstly. Enrichment analysis and molecular docking of those targets were performed to identify the possible mechanism of TSNⅠ against IS. Afterwards, experiments were carried out to further verify the mechanism of TSNⅠ against IS. The infarct volume and neurological deficit were evaluated by 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining and Longa respectively. Immunohistochemistry was used to observe neuronal death in the hippocampus and cortical regions by detecting the change of NeuN. The predicting pathways of signaling-related proteins were assessed by Western blot in vitro and in vivo experiments. RESULTS: In vivo, TSNⅠ was found to dose-dependently decrease mice's cerebral infarct volume induced by tMCAO. In vitro, pretreatment with TSNⅠ could increase cell viability of HT-22 cell following oxygen-glucose deprivation (OGD/R). Moreover, the results showed that 125 candidate targets were identified, Protein kinase B (AKT) signaling pathway was significantly enriched by Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and mitogen-activated protein kinases 1 (MAPK1) and AKT1 could be bound to TSNⅠ more firmly by molecular docking analysis, which implies that TSNⅠ may play a role in neuroprotection through activating AKT and MAPK signaling pathways. Meanwhile, TSNⅠ was confirmed to significantly protect neurons from injury induced by IS through activating AKT and MAPK signaling pathways. CONCLUSION: In conclusion, our study clarifies that the mechanism of TSNⅠ against IS might be related to AKT and MAPK signaling pathways, which may provide the basic evidence for further development and utilization of TSNⅠ.


Assuntos
Abietanos/farmacologia , AVC Isquêmico/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Abietanos/uso terapêutico , Abietanos/toxicidade , Animais , Isquemia Encefálica/complicações , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/metabolismo , AVC Isquêmico/etiologia , AVC Isquêmico/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos Endogâmicos ICR , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Simulação de Acoplamento Molecular , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo , Quinases raf/metabolismo
12.
Nat Commun ; 12(1): 449, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469028

RESUMO

Steroid hormones are essential in stress response, immune system regulation, and reproduction in mammals. Steroids with 3-oxo-Δ4 structure, such as testosterone or progesterone, are catalyzed by steroid 5α-reductases (SRD5As) to generate their corresponding 3-oxo-5α steroids, which are essential for multiple physiological and pathological processes. SRD5A2 is already a target of clinically relevant drugs. However, the detailed mechanism of SRD5A-mediated reduction remains elusive. Here we report the crystal structure of PbSRD5A from Proteobacteria bacterium, a homolog of both SRD5A1 and SRD5A2, in complex with the cofactor NADPH at 2.0 Å resolution. PbSRD5A exists as a monomer comprised of seven transmembrane segments (TMs). The TM1-4 enclose a hydrophobic substrate binding cavity, whereas TM5-7 coordinate cofactor NADPH through extensive hydrogen bonds network. Homology-based structural models of HsSRD5A1 and -2, together with biochemical characterization, define the substrate binding pocket of SRD5As, explain the properties of disease-related mutants and provide an important framework for further understanding of the mechanism of NADPH mediated steroids 3-oxo-Δ4 reduction. Based on these analyses, the design of therapeutic molecules targeting SRD5As with improved specificity and therapeutic efficacy would be possible.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/ultraestrutura , Proteínas de Bactérias/ultraestrutura , Esteroides/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/química , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Inibidores de 5-alfa Redutase/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Coenzimas/química , Coenzimas/metabolismo , Coenzimas/ultraestrutura , Cristalografia por Raios X , Desenho de Fármacos , Ligação de Hidrogênio , NADP/química , NADP/metabolismo , NADP/ultraestrutura , Oxirredução , Proteobactérias/enzimologia , Relação Estrutura-Atividade
13.
J Gen Psychol ; 148(1): 26-44, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-31851874

RESUMO

Internet language is a creative product of the rapid development of computer-mediated communication. The present study was to investigate whether the use of Internet language enhances creative problem solving. In Study 1, sixty-two selected participants were equally divided into two groups according to their use experience of Chinese Internet language, and then both more and less experienced groups were asked to complete Chinese remote associates test and Chinese chengyu riddles. Results showed that the more experienced group performed significantly better in both the creative tasks. In Study 2, forty-six participants were randomly divided into two groups. The experimental group was asked to learn Chinese Internet Language, while the control group was asked to learn scientific terminology. Two groups completed the aforementioned creative tasks in pretest and post-test. Results showed that the interaction between the group and test order was significant in Chinese chengyu riddle solving, in which the experimental group had a significantly higher average score in post-test than pretest. And there was no difference for the control group. These findings supported that Internet language use benefited creative problem solving, and it might be a convenient way in the practice of promoting creativity.


Assuntos
Criatividade , Idioma , Humanos , Internet , Resolução de Problemas
15.
J Biochem Mol Toxicol ; 35(3): e22658, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33118292

RESUMO

Oxidative stress, an imbalance between reactive oxygen species and antioxidants, has been seen in the pathological states of many disorders such as ischemic diseases and cancers. Many natural compounds (NCs) have long been recognized to ameliorate oxidative stress due to their inherent antioxidant activities. The modulation of oxidative stress by NCs via activating the Nrf2 signaling pathway is summarized in the review. Three NCs, ursolic acid, betulinic acid, and curcumin, and the mechanisms of their cytoprotective effects are investigated in myocardial ischemia, cerebral ischemia, skin cancer, and prostate cancer. To promote the therapeutic performance of NCs with poor water solubility, the formulation approach, such as the nano drug delivery system, is elaborated as well in this review.


Assuntos
Isquemia Encefálica , Isquemia Miocárdica , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas de Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/uso terapêutico , Neoplasias da Próstata , Neoplasias Cutâneas , Isquemia Encefálica/tratamento farmacológico , Humanos , Masculino , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo
16.
PLoS Genet ; 16(6): e1008892, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32569316

RESUMO

Nicotinamide adenine dinucleotide (NAD) is an essential coenzyme that has emerged as a central hub linking redox equilibrium and signal transduction in living organisms. The homeostasis of NAD is required for plant growth, development, and adaption to environmental cues. In this study, we isolated a chilling hypersensitive Arabidopsis thaliana mutant named qs-2 and identified the causal mutation in the gene encoding quinolinate synthase (QS) critical for NAD biosynthesis. The qs-2 mutant is also hypersensitive to salt stress and abscisic acid (ABA) but resistant to drought stress. The qs-2 mutant accumulates a reduced level of NAD and over-accumulates reactive oxygen species (ROS). The ABA-hypersensitivity of qs-2 can be rescued by supplementation of NAD precursors and by mutations in the ABA signaling components SnRK2s or RBOHF. Furthermore, ABA-induced over-accumulation of ROS in the qs-2 mutant is dependent on the SnRK2s and RBOHF. The expression of QS gene is repressed directly by ABI4, a transcription factor in the ABA response pathway. Together, our findings reveal an unexpected interplay between NAD biosynthesis and ABA and stress signaling, which is critical for our understanding of the regulation of plant growth and stress responses.


Assuntos
Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Complexos Multienzimáticos/genética , Reguladores de Crescimento de Plantas/metabolismo , Estresse Fisiológico/genética , Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/isolamento & purificação , Proteínas de Arabidopsis/metabolismo , Retroalimentação Fisiológica , Perfilação da Expressão Gênica , Complexos Multienzimáticos/isolamento & purificação , Complexos Multienzimáticos/metabolismo , Mutação , NAD/biossíntese , NADPH Oxidases/metabolismo , Plantas Geneticamente Modificadas , Proteínas Serina-Treonina Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/isolamento & purificação , Fatores de Transcrição/metabolismo
17.
Dev Sci ; 23(2): e12895, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31433880

RESUMO

Over the last 15 years, researchers have been increasingly interested in understanding the nature and development of children's selective trust. Three meta-analyses were conducted on a total of 51 unique studies (88 experiments) to provide a quantitative overview of 3- to 6-year-old children's selective trust in an informant based on the informant's epistemic or social characteristics, and to examine the relation between age and children's selective trust decisions. The first and second meta-analyses found that children displayed medium-to-large pooled effects in favor of trusting the informant who was knowledgeable or the informant with positive social characteristics. Moderator analyses revealed that 4-year-olds were more likely to endorse knowledgeable informants than 3-year-olds. The third meta-analysis examined cases where two informants simultaneously differed in their epistemic and social characteristics. The results revealed that 3-year-old children did not selectively endorse informants who were more knowledgeable but had negative social characteristics over informants who were less knowledgeable but had positive social characteristics. However, 4- to 6-year-olds consistently prioritized epistemic cues over social characteristics when deciding who to trust. Together, these meta-analyses suggest that epistemic and social characteristics are both valuable to children when they evaluate the reliability of informants. Moreover, with age, children place greater value on epistemic characteristics when deciding whether to endorse an informant's testimony. Implications for the development of epistemic trust and the design of studies of children's selective trust are discussed.


Assuntos
Conhecimento , Fatores Sociológicos , Confiança , Fatores Etários , Criança , Pré-Escolar , Sinais (Psicologia) , Tomada de Decisões , Feminino , Humanos , Julgamento , Masculino
18.
Brain Res ; 1726: 146513, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669828

RESUMO

The integration of text and picture is the core of multimedia information processing. Relevant theories suggest that text and picture are processed through different channels in the early stage, and integrated in the late stage of processing. Based on these theories, the current study adopted measures of event-related potentials to examine the cognitive and neural processes of text-picture integration. The results showed that in the early stage of text-picture integration, picture processing evoked a more negative N1 over the occipital area and a N300 over the prefrontal area, which might reflect the discrimination process of visual stimuli and the imagery representation of the picture, respectively; in the late stage, the text-picture induced a N400 in the central area and an LPC over the central, parietal and temporal areas, which might be associated with the semantic activation and integration of text and picture, respectively. These results not only provide support for existing theories, but also further elucidate the dynamic neural processing of text-picture integration in terms of its temporal and spatial characteristics.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Potenciais Evocados , Semântica , Percepção Visual/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Leitura , Adulto Jovem
19.
Sci Rep ; 9(1): 8024, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142761

RESUMO

Precipitation minus evaporation over continents is the freshwater flux which can be sustainably exploited by mankind. Over a catchment and longer time periods, this flux is also the amount of water which flows into the ocean. An essential question for semi-arid areas of the world is how well this freshwater flux can be estimated and predicted to evolve under climate change and human water use. Knowing this flux is thus an essential element in regional water resources management. Here we examine this question over the catchment of the Mediterranean Sea. Using a novel data assimilation methodology that incorporates observed discharges of rivers in a land surface model, new estimates of the freshwater flux to the Mediterranean Sea for the period 1980-2013 are proposed. We find that more freshwater (40-60%) flows into the sea than previously estimated. The hypothesis we advance is that previous estimates have underestimated the discharges of the large number of unmonitored coastal basins and neglected submarine ground water flows. The proposed error bars on the estimate indicate that the degrading river gauging station network limits our ability to monitor this branch of the water cycle reliably. Nevertheless, the uncertainty is small enough to allow the identification of regions in which non-climatic decreases in the freshwater flows exist over the period.

20.
Nat Commun ; 8(1): 1183, 2017 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084945

RESUMO

Drought stress is a major threat to crop production, but effective methods to mitigate the adverse effects of drought are not available. Here, we report that adding fluorine atoms in the benzyl ring of the abscisic acid (ABA) receptor agonist AM1 optimizes its binding to ABA receptors by increasing the number of hydrogen bonds between the compound and the surrounding amino acid residues in the receptor ligand-binding pocket. The new chemicals, known as AMFs, have long-lasting effects in promoting stomatal closure and inducing the expression of stress-responsive genes. Application of AMFs or transgenic overexpression of the receptor PYL2 in Arabidopsis and soybean plants confers increased drought resistance. The greatest increase in drought resistance is achieved when AMFs are applied to the PYL2-overexpression transgenic plants. Our results demonstrate that the combining of potent chemicals with transgenic overexpression of an ABA receptor is very effective in helping plants combat drought stress.


Assuntos
Ácido Abscísico/análogos & derivados , Proteínas de Arabidopsis/agonistas , Arabidopsis/fisiologia , Flúor/química , Água/fisiologia , Proteínas de Arabidopsis/metabolismo , Secas , Escherichia coli , Regulação da Expressão Gênica de Plantas , Estrutura Molecular , Plantas Geneticamente Modificadas , Proteína Fosfatase 2C/metabolismo , Glycine max
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