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Soil salinization, especially in arid environments, is a leading cause of land degradation and desertification. Excessive salt in the soil is detrimental to plants. Plants have developed various sophisticated regulatory mechanisms that allow them to withstand adverse environments. Through cross-adaptation, plants improve their resistance to an adverse condition after experiencing a different kind of adversity. Our analysis of Ammopiptanthus nanus, a desert shrub, showed that mechanical wounding activates the biosynthesis of jasmonic acid (JA) and abscisic acid (ABA), enhancing plasma membrane H+-ATPase activity to establish an electrochemical gradient that promotes Na+ extrusion via Na+/H+ antiporters. Mechanical wounding reduces K+ loss under salt stress, improving the K/Na and maintaining root ion balance. Meanwhile, mechanical damage enhances the activity of antioxidant enzymes and the content of osmotic substances, working together with cellular ions to alleviate water loss and growth inhibition under salt stress. This study provides new insights and approaches for enhancing salt tolerance and stress adaptation in plants by elucidating the signaling mechanisms of cross-adaptation.
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Standard learning assessments like multiple-choice questions measure what students know but not how their knowledge is organized. Recent advances in cognitive network science provide quantitative tools for modeling the structure of semantic memory, revealing key learning mechanisms. In two studies, we examined the semantic memory networks of undergraduate students enrolled in an introductory psychology course. In Study 1, we administered a cumulative multiple-choice test of psychology knowledge, the Intro Psych Test, at the end of the course. To estimate semantic memory networks, we administered two verbal fluency tasks: domain-specific fluency (naming psychology concepts) and domain-general fluency (naming animals). Based on their performance on the Intro Psych Test, we categorized students into a high-knowledge or low-knowledge group, and compared their semantic memory networks. Study 1 (N = 213) found that the high-knowledge group had semantic memory networks that were more clustered, with shorter distances between concepts-across both the domain-specific (psychology) and domain-general (animal) categories-compared to the low-knowledge group. In Study 2 (N = 145), we replicated and extended these findings in a longitudinal study, collecting data near the start and end of the semester. In addition to replicating Study 1, we found the semantic memory networks of high-knowledge students became more interconnected over time, across both domain-general and domain-specific categories. These findings suggest that successful learners show a distinct semantic memory organization-characterized by high connectivity and short path distances between concepts-highlighting the utility of cognitive network science for studying variation in student learning.
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A lipidated polysaccharide, HDPS-2II, was isolated from the dried larva of Holotrichia diomphalia, which is used in traditional Chinese medicine. The molecular weight of HDPS-2II was 5.9 kDa, which contained a polysaccharide backbone of â4)-ß-Manp-(1 â 4,6)-ß-Manp-(1 â [6)-α-Glcp-(1]n â 6)-α-Glcpâ with the side chain α-Glcp-(6 â 1)-α-Glcp-(6 â linked to the C-4 of ß-1,4,6-Manp and four types of lipid chains including 4-(4-methyl-2-(methylamino)pentanamido)pentanoic acid, 5-(3-(tert-butyl)phenoxy)hexan-2-ol, N-(3-methyl-5-oxopentan-2-yl)palmitamide, and N-(5-amino-3-methyl-5-oxopentan-2-yl)stearamide. The lipid chains were linked to C-1 of terminal α-1,6-Glcp in carbohydrate chain through diacyl-glycerol. HDPS-2II exhibited DNA protective effects and antioxidative activity on H2O2- or adriamycin (ADM)-induced Chinese hamster lung cells. Furthermore, HDPS-2II significantly ameliorated chromosome aberrations and the accumulation of reactive oxygen species (ROS), reduced γ-H2AX signaling and the expressions of NADPH oxidase (NOX)2, NOX4, P22phox, and P47phox in ADM-induced cardiomyocytes. Mechanistically, HDPS-2II suppressed ADM-induced up-regulation of NOX2 and NOX4 in cardiomyocytes, but not in NOX2 or NOX4 knocked-down cardiomyocytes, indicating that HDPS-2II could relieve intracellular DNA damage by regulating NOX2/NOX4 signaling. These findings demonstrate that HDPS-2II is a new potential DNA protective agent.
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Dano ao DNA , Glicolipídeos , Animais , Dano ao DNA/efeitos dos fármacos , Glicolipídeos/farmacologia , Glicolipídeos/química , Besouros , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/química , Cricetulus , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificaçãoRESUMO
A distinct family of plant-specific WRKY transcription factors plays a crucial role in modulating responses to biotic and abiotic stresses. In this investigation, we unveiled a signaling pathway activated in the desert shrub Ammopiptanthus nanus during feeding by the moth Spodoptera exigua. The process involves a Ca2+ flux that facilitates interaction between the protein kinase AnCIPK12 and AnWRKY29. AnWRKY29 directly interacts with the promoters of two key genes encoding AnPDF1 and AnHsfB1, involved in the biosynthesis of plant defensins. Consequently, AnWRKY29 exerts its transcriptional regulatory function, influencing plant defensins biosynthesis. This discovery implies that A. nanus can bolster resistance against herbivorous insects like S. exigua by utilizing this signaling pathway, providing an effective natural defense mechanism that supports its survival and reproductive success.
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Defensinas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Defensinas/genética , Defensinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Spodoptera/genética , Transdução de Sinais , Regiões Promotoras Genéticas , Clima Desértico , HerbivoriaRESUMO
Microplastic (MP) pollution has caused severe concern due to its harmful effect on human beings and ecosystems. Existing MP removal methods face many obstacles, such as high cost, high energy consumption, low efficiency, release of toxic chemicals, etc. Thus, it is crucial to find appropriate and sustainable methods to replace common MP removal approaches. Bio-electrochemical system (BES) is a sustainable clean energy technology that has been successfully applied to wastewater treatment, seawater desalination, metal removal, energy production, biosensors, etc. However, research reports on BES technology to eliminate MP pollution are limited. This paper reviews the mechanism, hazards, and common treatment methods of MP removal and discusses the application of BES systems to improve MP removal efficiency and sustainability. Firstly, the characteristics and limitations of common MP removal techniques are systematically summarized. Then, the potential application of BES technology in MP removal is explored. Furthermore, the feasibility and stability of the potential BES MP removal application are critically evalauted while recommendations for further research are proposed.
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Microplásticos , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Microplásticos/análise , Eliminação de Resíduos Líquidos/métodos , Técnicas Eletroquímicas/métodos , Águas Residuárias/química , Purificação da Água/métodosRESUMO
Trehalose, a biological macromolecule with osmotic adjustment properties, plays a crucial role during osmotic stress. As a psammophyte, Ammopiptanthus nanus relies on the accumulation of organic solutes to respond to osmotic stress. We utilized virus-induced gene silencing technology for the first time in the desert shrub A. nanus to confirm the central regulatory role of AnWRKY29 in osmotic stress, as it controls the transcription of AnTPS11 (trehalose-6-phosphate synthase 11). Further investigation has shown that AnHSP90 may interact with AnWRKY29. The AnHSP90 gene is sensitive to osmotic stress, underscoring its pivotal role in orchestrating the response to such adverse conditions. By directly targeting the W-box element within the AnTPS11 promoter, AnWRKY29 effectively enhances the transcriptional activity of AnTPS11, which is facilitated by AnHSP90. This discovery highlights the critical role of AnWRKY29 and AnHSP90 in enabling organisms to adapt to and cope effectively with osmotic stress, which can be a crucial factor in A. nanus survival and overall ecological resilience. Collectively, uncovering the molecular mechanisms underlying the osmotic responses of A. nanus is paramount for comprehending and augmenting the osmotic tolerance mechanisms of psammophyte shrub plants.
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Fabaceae , Trealose , Pressão Osmótica , Folhas de Planta/genética , OsmoseRESUMO
Given the detrimental impact of global warming on crop production, it is particularly important to understand how plants respond and adapt to higher temperatures. Using the non-invasive micro-test technique and laser confocal microscopy, we found that the cascade process of early signals (K+, H2O2, H+, and Ca2+) ultimately resulted in an increase in the cytoplasmic Ca2+ concentration when Arabidopsis was exposed to heat stress. Quantitative real-time PCR demonstrated that heat stress significantly up-regulated the expression of CAM1, CAM3 and HSFA2; however, after CAM1 and CAM3 mutation, the upregulation of HSFA2 was reduced. In addition, heat stress affected the expression of LOX3 and OPR3, which was not observed when HSFA2 was mutated. Luciferase reporter gene expression assay and electrophoretic mobility shift assay showed that HSFA2 regulated the expression of both genes. Determination of jasmonic acid (JA) content showed that JA synthesis was promoted by heat stress, but was damaged when HSFA2 and OPR3 were mutated. Finally, physiological experiments showed that JA reduced the relative electrical conductivity of leaves, enhanced chlorophyll content and relative water content, and improved the survival rate of Arabidopsis under heat stress. Together, our results reveal a new pathway for Arabidopsis to sense and transmit heat signals; HSFA2 is involved in the JA synthesis, which can act as a defensive compound improving Arabidopsis heat tolerance.
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Proteínas de Arabidopsis , Arabidopsis , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Choque Térmico , Resposta ao Choque Térmico , Oxilipinas , Transdução de Sinais , Termotolerância , Arabidopsis/genética , Arabidopsis/metabolismo , Oxilipinas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Termotolerância/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Cálcio/metabolismo , MutaçãoRESUMO
BACKGROUND: Poststroke cognitive impairment is a severe and common clinical complication that constitutes a substantial global health burden. We aimed to evaluate the association of 3 cardiac biomarkers in combination with poststroke cognitive impairment and their prognostic significance. METHODS AND RESULTS: This prospective study included 566 patients with ischemic stroke. Cardiac biomarkers, including sST2 (soluble suppression of tumorigenicity-2 receptor), GDF-15 (growth differentiation factor-15), and NT-proBNP (N-terminal pro-B-type natriuretic peptide), were measured. Cognitive impairment was defined as a Mini-Mental State Examination score of <27 or a Montreal Cognitive Assessment score of <25 at 3 months after ischemic stroke. Odds of cognitive impairment 3 months after ischemic stroke increased with the number of elevated cardiac biomarkers (sST2, GDF-15, and NT-proBNP; Ptrend<0.001). The multivariable adjusted odds ratios (95% CIs) of cognitive impairment defined by the Mini-Mental State Examination and Montreal Cognitive Assessment were 2.45 (1.48-4.07) and 1.86 (1.10-3.14) for the participants with ≥2 elevated cardiac biomarkers, respectively, compared with those without any elevated cardiac biomarker. Additionally, higher cardiac biomarker scores were associated with an increased risk of cognitive impairment (Ptrend<0.05). Simultaneously adding all 3 cardiac biomarkers to the basic model with traditional risk factors significantly improved the risk prediction of Mini-Mental State Examination-defined cognitive impairment (net reclassification improvement=34.99%, P<0.001; integrated discrimination index=2.67%, P<0.001). Similar findings were observed using the Montreal Cognitive Assessment scores. CONCLUSIONS: An increased number of elevated novel cardiac biomarkers were associated with an increased odds of poststroke cognitive impairment, suggesting that a combination of these cardiac biomarkers may improve the risk prediction of cognitive impairment. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01840072.
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Disfunção Cognitiva , AVC Isquêmico , Humanos , Biomarcadores , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Fator 15 de Diferenciação de Crescimento , AVC Isquêmico/complicações , Estudos ProspectivosRESUMO
BACKGROUND: The incidence of stroke in China ranks first in the world and is the leading cause of death and disability in adults. Urinary incontinence is an independent risk factor leading to poor prognosis of stroke. However, studies on the incidence of urinary incontinence in stroke patients and its influencing factors are different, fluctuate greatly, and there is no unified basis. OBJECTIVE: To quantitatively analyze the incidence of urinary incontinence in stroke patients and its related influencing factors, and further make public health strategic decisions to reduce the occurrence of adverse outcomes. METHODS: Computer searches were conducted in PubMed, Medline, Web of Science, Cochrane Library, Embase, CLNAHL Complete, China National Knowledge Infrastructure (CNKI), Chinese Biomedical database(CBM), Wan Fang Database, VIP Database, observational studies such as cohort studies, case-control studies or cross-sectional studies on the incidence or influencing factors of urinary incontinence in stroke patients from the establishment of the database to the publication in August 2023. Studies selection, quality evaluation and data extraction were conducted independently by two researchers according to the established search strategy. Stata 14.0 statistical software was used for meta-analysis. RESULTS: A total of 21 manuscripts were included, with a cumulative sample size of 7327 cases, including 2887 patients with urinary incontinence. Meta-analysis results showed that the incidence of urinary incontinence in stroke patients was 38% [95% confidence interval (34%, 41%)], including married patients and lacunar infarction were the protective factors for urinary incontinence in stroke patients, while age, chaperone, low educational level, chronic cough, lesion sites (parietal lobe, frontal lobe, and temporal lobe), stroke type (cerebral hemorrhage, subarachnoid hemorrhage and cerebral hemorrhage complicated with subarachnoid hemorrhage), dysfunction (aphasia dyslexia, dysphagia, eye movement abnormalities, leg muscle disorders), post-stroke depression, the higher the NIHSS score, the lower the Bachmann index (BI) score, OCSP classification (total anterior circulation infarction) and other 11 items were risk factors for urinary incontinence in stroke patients. CONCLUSION: The incidence of urinary incontinence in stroke patients is 38%. Marriage and lacunar infarction are the protective factors of urinary incontinence. Age, carer, low educational level, chronic cough, lesion site (parietal, frontal and temporal lobes), stroke type (cerebral hemorrhage, subarachnoid hemorrhage, cerebral hemorrhage combined with subarachnoid hemorrhage), dysfunction (aphasia and dysarthria syndrome, dysphagia, eye movement abnormalities, leg muscle disorders), post-stroke depression, and higher NIHSS score, Lower BI score and OCSP classification (total anterior circulation infarction) were risk factors for urinary incontinence in stroke patients.
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Acidente Vascular Cerebral , Incontinência Urinária , Humanos , Incontinência Urinária/epidemiologia , Incontinência Urinária/fisiopatologia , Incontinência Urinária/etiologia , Incidência , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , China/epidemiologiaRESUMO
Volatile organic compounds (VOCs) play key roles in plant-plant communication, especially in response to pest attack. E-2-hexenal is an important component of VOCs, but it is unclear whether it can induce endogenous plant resistance to insects. Here, we show that E-2-hexenal activates early signaling events in Arabidopsis (Arabidopsis thaliana) mesophyll cells, including an H2O2 burst at the plasma membrane, the directed flow of calcium ions, and an increase in cytosolic calcium concentration. Treatment of wild-type Arabidopsis plants with E-2-hexenal increases their resistance when challenged with the diamondback moth Plutella xylostella L., and this phenomenon is largely lost in the wrky46 mutant. Mechanistically, E-2-hexenal induces the expression of WRKY46 and MYC2, and the physical interaction of their encoded proteins was verified by yeast two-hybrid, firefly luciferase complementation imaging, and in vitro pull-down assays. The WRKY46-MYC2 complex directly binds to the promoter of RBOHD to promote its expression, as demonstrated by luciferase reporter, yeast one-hybrid, chromatin immunoprecipitation, and electrophoretic mobility shift assays. This module also positively regulates the expression of E-2-hexenal-induced naringenin biosynthesis genes (TT4 and CHIL) and the accumulation of total flavonoids, thereby modulating plant tolerance to insects. Together, our results highlight an important role for the WRKY46-MYC2 module in the E-2-hexenal-induced defense response of Arabidopsis, providing new insights into the mechanisms by which VOCs trigger plant defense responses.
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Aldeídos , Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Flavonoides/metabolismo , Saccharomyces cerevisiae/metabolismo , Cálcio/metabolismo , Peróxido de Hidrogênio/metabolismo , Plantas/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismoRESUMO
Attentional scaling is a crucial mechanism that enables us to flexibly allocate our attention to larger or smaller regions in the visual field. Although previous studies have demonstrated the critical role of attentional scaling in visual processing, its impact on modulating visual awareness is not yet fully understood. This study investigates the adaptive control of attentional scaling and its influence on visual awareness in an attentional blink paradigm. Participants were required to attend to the first target's location, which was manipulated either session-wise, trial-wise, or such that it could be learned across a block of trials. Discrete, all-or-none, awareness was expected when attention was allocated to a narrow area, while gradual awareness was expected when attention was allocated to a larger area. We used mixture modeling to assess second target awareness across these different attentional scales. The results revealed that participants could adaptively control their attentional scale both across stable sessions, and through (implicit) statistical learning in blocks of successive trials. This produced gradual perceptual awareness when the participants adopted a broad attentional scale, causing an attentional "blur". However, trial-wise cues did not allow for attentional scaling, resulting in more discrete target perception overall, and an attentional "blink". We conclude that the attentional scale is to some extent under adaptive control during the attentional blink/blur, where it can produce qualitatively different modes of perceptual awareness.
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Intermitência na Atenção Visual , Percepção Visual , Humanos , Sinais (Psicologia) , AprendizagemRESUMO
OBJECTIVE: To investigate the effect of consistently blood pressure (BP) control status after discharge on adverse clinical outcomes among ischemic stroke (IS) patients. METHODS: Three thousand, four hundred and six acute IS patients were included and followed up at 3âmonths, 12âmonths, and 24âmonths after stroke. Study outcomes were defined as death, vascular events and composite of death or vascular events. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confident interval (CI) of death and the composite outcome of death or vascular events associated with BP control and antihypertensive medication use. RESULTS: The multivariable adjusted HRs were 0.22 [95% confidence interval (CI): 0.09-0.57] for death and 0.60 (95% CI: 0.39-0.97) for the composite outcome of death or vascular events among participants with consistently controlled BP compared with those with consistently uncontrolled BP. The participants with both consistently controlled BP and regular use of antihypertensive medication had the lowest risks of death [hazard ratio (HR): 0.18, 95% CI: 0.04-0.75] and composite outcome of death or vascular events (HR: 0.54, 95% CI: 0.29-0.98) in comparison with those with both uncontrolled BP and irregular use of antihypertensive medication. DISCUSSION: Continuous BP control and regular use of antihypertensive medications after discharge can decrease the risks of death and composite outcome of death or vascular events among IS patients, suggesting the importance of continuous BP control and regular use of antihypertensive medications after discharge for improving prognosis of IS.
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Hipertensão , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Pressão Sanguínea/fisiologia , Anti-Hipertensivos/uso terapêutico , Anti-Hipertensivos/farmacologia , Alta do Paciente , Prognóstico , Acidente Vascular Cerebral/tratamento farmacológico , Hipertensão/complicações , Hipertensão/tratamento farmacológicoRESUMO
OBJECTIVE: This study aimed to evaluate the improvement of cognitive impairment in older adults through probiotic supplementation. METHODS: A literature review on probiotic supplementation for treating cognitive impairment in older adults was conducted using English and Chinese databases from 1984 to 2023. Two researchers extracted relevant data independently, and a meta-analysis was performed with RevMan software. RESULTS: A comprehensive analysis of ten pertinent papers was conducted, involving a sample of 702 old adults with cognitive impairment. The findings from this study revealed that probiotic supplementation exhibited a positive impact on cognitive symptoms, specifically memory (MD = 0.14, 95% CI :0.05ï½0.22, P = 0.001) and overall cognitive function (SMD = 0.73, 95% CI: 0.25ï½1.21, P=0.003), as well as oxidative stress levels, including total antioxidant capacity (MD=52.54, 95% CI:39.52ï½65.56, P < 0.01), malondialdehyde (MD=-0.11, 95% CI:-0.15ï½-0.07, P < 0.01), and glutathione (MD=17.08, 95% CI:8.65ï½25.5, P < 0.01). However, probiotic supplementation failed to enhance patients' psychological symptoms (SMD =0.18, 95% CI:-0.56ï½0.92, P = 0.64). CONCLUSIONS: Probiotic supplementation can enhance cognitive symptoms and decrease oxidative stress in older adults with cognitive impairment. However, it does not improve psychological symptoms. More research is needed to determine the effects of probiotic supplementation on gastrointestinal symptoms and sleep quality in this population. Further supplementation and improvement will be necessary once high-quality literature becomes available.
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Disfunção Cognitiva , Probióticos , Humanos , Idoso , Probióticos/uso terapêutico , Probióticos/farmacologia , Cognição , Disfunção Cognitiva/terapiaRESUMO
Introduction: The leaf-chewing pest Heortia vitessoides severely threatens the growth and development of Aquilaria sinensis. In our previous study, we found that mechanical damage (MD) to stem enhanced A. sinensis sapling resistance to H. vitessoides larvae. Methods: To reveal the defense mechanisms underlying this observation, we analyzed the types and contents of volatile organic compounds (VOCs), phytohormone contents, and expression of phytohormone-related genes in response to MD and herbivory wounding(HW). Results: Here, we identified several VOCs, such as the pesticides fenobucarb and 2,4-di-tert-butylphenol, in mature leaf (ML) of MD-treated plants. Compared with salicylic acid (SA) or the ethylene (ET) pathway, jasmonic acid (JA) content and JA-related genes were more strongly upregulated. Interestingly, we found a dramatic difference between JA-related upstream and downstream genes expression in YL and ML, which confirmed that JA-Ile accumulation in MD-ML and HW-ML could be derived from local damaged site. Discussion: Taken together, we provide evidence that the JA pathway plays a dominant role in the A. sinensis response to MD and HW.
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Herein, we have successfully synthesized two rubidium antimony (III) oxalates, namely, Rb2Sb(C2O4)2.5(H2O)3 and RbSb2(C2O4)F5, utilizing a low-temperature hydrothermal method. These two compounds share a similar chemical composition, consisting of Sb3+ cations with active lone pair electrons, alkali metal Rb+ ions, and planar π-conjugated C2O42- anions. However, they exhibit different symmetries, Rb2Sb(C2O4)2.5(H2O)3 is centrosymmetric (CS), while RbSb2(C2O4)F5 is noncentrosymmetric (NCS), which should be caused by the presence of F- ions. Notably, the NCS compound, RbSb2(C2O4)F5, demonstrates a moderate second-harmonic generation (SHG) response, approximately 1.3 times that of KH2PO4 (KDP), and exhibits a large birefringence of 0.09 at 546 nm. These characteristics indicate that RbSb2(C2O4)F5 holds promising potential as a nonlinear optical material for ultraviolet (UV) applications. Detailed structural analysis and theoretical calculations confirm that the excellent optical properties arise from the synergistic effects between Sb3+ cations with SCALP and planar π-conjugated [C2O4]2- groups.
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As a significant transcription factor family in plants, WRKYs have a crucial role in responding to different adverse environments. They have been repeatedly demonstrated to contribute to drought resistance. However, no systematic exploration of the WRKY family has been reported in the evergreen shrub Ammopiptanthus nanus under drought conditions. Here, we showed that AnWRKY29 expression is strongly induced under drought stress. AnWRKY29 belongs to the group IIe of WRKY gene family. To characterize the function of AnWRKY29, we generated transgenic plants overexpressing this gene in Arabidopsis thaliana. We determined that AnWRKY29 overexpression of mainly improves the drought resistance of transgenic plants to water stress by reducing water loss, preventing electrolyte leakage, and increasing the absorption of inorganic ions. In addition, the AnWRKY29 transgenic plants synthesized more trehalose under water stress. The overexpression of AnWRKY29 also enhanced the antioxidant and osmoregulation capacity of transgenic plants by increasing the activities of catalase, peroxidase and superoxide dismutase, thus increasing the scavenging of reactive oxygen species and propylene glycol synthesis aldehyde oxidase. In summary, our study shows that AnWRKY29 plays an important role in the drought tolerance pathway in plants.
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The effective and economical 3D floating air cathodes were fabricated by a simple dipping-drying method with carbon black (CB), ethanol, and PTFE solution. Pristine Type I polyurethane sponge (5 pores/mm) and Pristine Type II polyurethane sponge (3 pores/mm) were used as the support. The deposition of CB on the Pristine Type I and Pristine Type II materials was detected by scanning electron microscopy and Fourier transform infrared spectroscopy. The carbon loss rate test exhibited good CB adhesive stability on both floating air cathodes. Besides, Type I/CB floating air cathode displayed 3.7 times higher tensile strength, 10.58 times higher elongation at break, and 3.3 times lower cost than carbon felt. The electricity production ability of carbon cloth (CC) anode with carbon felt, Type I/CB, and Type II/CB cathode MFCs (CC-CF-MFC, CC-I-MFC, and CC-II-MFC) was evaluated. After 130 days, the CC-I-MFC showed a maximum power density (PD) of 92.58 mW/m3, which was 4.6 times higher than the CC-CF-MFC. Compared with Type II/CB, Type I/CB cathode improved the maximum power density by 160% due to the smaller pores, rougher surface, and higher surface wettability. Further, CC-I-MFC exhibited the best overall oxidation-reduction performance and chemical oxygen demand removal efficiency. Consequently, Type I/CB floating air cathode opens a new opportunity for scaling up simple, inexpensive, and high-performance MFCs for energy production.
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Loss of bone mass can occur in mammals after prolonged disuse but the situation for hibernators that are in a state of torpor for many months of the year is not yet fully understood. The present study assesses the bone remodeling mechanisms present in Daurian ground squirrels (Spermophilus dauricus) during hibernation as compared with a model of hindlimb disuse. Differences in microstructure, mechanical properties, bone remodeling-related proteins (Runx2, OCN, ALP, RANKL, CTK and MMP-9) and key proteins of Wnt/ß-catenin signaling pathway (GSK-3ß and phospho-ß-catenin) were evaluated in ground squirrels under 3 conditions: summer active (SA) vs. hibernation (HIB) vs. hindlimb unloaded (HLU). The results indicated that the body weight in HLU ground squirrels was lower than the SA group, and the middle tibia diameter in the HLU group was lower than that in SA and HIB groups. The thickness of cortical and trabecular bone in femurs from HLU ground squirrels was lower than in SA and HIB groups. Most parameters of the tibia in the HLU group were lower than those in SA and HIB groups, which indicated cortical bone loss in ground squirrels. Moreover, our data showed that the changes in microscopic parameters in the femur were more obvious than those in the tibia in HLU and HIB ground squirrels. The levels of Runx2 and ALP were lower in HLU ground squirrels than SA and HIB groups. The protein levels of OCN were unchanged in the three groups, but the protein levels of ALP were lower in the HLU group than in SA and HIB groups. RANKL, CTK and MMP-9 protein levels were significantly decreased in tibia of HLU ground squirrels as compared with SA and HIB groups. In addition, the protein expression levels of RANKL, CTK and MMP-9 showed no statistical difference between SA and HIB ground squirrels. Thus, the mechanisms involved in the balance between bone formation and resorption in hibernating and hindlimb unloading ground squirrels may be different. The present study showed that in femur, the Wnt signaling pathway was inhibited, the protein level of GSK-3ß was increased, and the protein expression of phospho-ß-catenin was decreased in the HIB group as compared with the SA group, which indicates that the Wnt signaling pathway has a great influence on the femur of the HIB group. In conclusion, the natural anti-osteoporosis properties of Daurian ground squirrels are seasonal. The squirrels do not experience bone loss when they are inactive for a long time during hibernation, but the mechanisms of anti-osteoporosis did not work in HLU summer active squirrels.
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Subunidade alfa 1 de Fator de Ligação ao Core , Hibernação , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , beta Catenina/metabolismo , Sciuridae/fisiologia , Elevação dos Membros Posteriores , Remodelação Óssea , Membro Posterior/fisiologia , Hibernação/fisiologiaRESUMO
Neuromedin U (NMU) has a critical function on the regulation of food intake in mammals, while the information is little in teleost. To investigate the function of NMU on appetite regulation of Siberian sturgeon (Acipenser baerii), this study first cloned nmu cDNA sequence that encoded 154 amino acids including NMU-25 peptide. Besides, the results showed that nmu mRNA was widely distributed in various tissues especially in the hypothalamus and telencephalon. The results of nutritional status (pre-feeding and post-feeding, fasting and re-feeding) experiments showed that nmu mRNA expression was significantly decreased at 1 and 3 h after feeding in different brain regions. Similarly, after feeding, the expression of nmu significantly decreased in peripheral tissues. Moreover, nmu expression in the hypothalamus was significantly increased after fasting 1 d, but decreased after fasting 17 d, which was significantly reversed after re-feeding. However, other brain regions like telencephalon and peripheral tissues like oesophagus, intestinum valvula and liver have different change patterns. Further study showed that acute i.c.v. and i.p. injection of NMU and chronic i.p. injection of NMU significantly reduced the food intake in a dose-dependent mode. In addition, the expressions of several critical appetite factors (nmu, aplein, cart, cck, ghrelin, npy, nucb2, pyy and ucn3) were significantly affected by acute NMU-25 administration in the hypothalamus, intestinum valvula and liver. These results indicate that NMU-25 has the anorexigenic function on food intake by affecting different appetite factors in Siberian sturgeon, which provides a foundation for further exploring the appetite regulation networks in fish.