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1.
Food Sci Nutr ; 11(4): 2049-2060, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37051347

RESUMO

Okra pod is sensitive to low temperature, which results in chilling injury under improper low-temperature storage. This study aimed to evaluate the effect of different concentrations of methyl jasmonate (MeJA) treatment on okra pod stored at 4 ± 1°C for 12 days and illuminate the mechanism of MeJA alleviating chilling injury. Compared to the control, MeJA treatments maintained lower relative electric conductivity (REC), chilling injury (CI) degree, and lignin content, as well as higher total soluble solids, total soluble sugar, pectin content, and chlorophyll content. The factor analysis was applied to comprehensively evaluate the effects of MeJA so that 1 µmol/L MeJA was screened as the optimum concentration to maintain the okra quality throughout the storage time. In contrast with control, MeJA not only accelerated the generation of antioxidant substances (phenolics and flavonoids) but also increased the superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activity, inhibited malondialdehyde (MDA), hydrogen peroxide (H2O2) content accumulation, and the polyphenol oxidase (PPO) activity. This work confirmed that MeJA could effectively alleviate chilling injury and maintain the quality during cold-stored by regulating reactive oxygen species (ROS) metabolism. These results provide theoretical guidance for the application of MeJA in okra storage and preservation.

2.
PeerJ ; 11: e14637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655051

RESUMO

Background: The calmodulin-like (CML) protein is a crucial Ca2+-binding protein that can sense and conduct the Ca2+ signal in response to extracellular stimuli. The CML protein families have been identified and characterized in many species. Nevertheless, scarce information on cucumber CML is retrievable. Methods: In this study, bioinformatic analyses, including gene structure, conserved domain, phylogenetic relationship, chromosome distribution, and gene synteny, were comprehensively performed to identify and characterize CsCML gene members. Spatiotemporal expression analysis in different organs and environment conditions were assayed with real-time quantitative polymerase chain reaction (qRT-PCR). Results: Forty-four CsCMLs family members were well characterized, and the results showed that the 44 CsCML proteins contained one to four EF-hand domains without other functional domains. Most of the CsCML proteins were intron-less and unevenly distributed on seven chromosomes; two tandemly duplicated gene pairs and three segmentally duplicated gene pairs were identified in the cucumber genome. Cis-acting element analysis showed that the hormone, stress, and plant growth and development-related elements were in the promotor regions. In addition, spatiotemporal expression analysis revealed distinctive expression patterns for CsCML genes in different tissues and environmental conditions, and a putative protein interaction network also confirmed their potential role in responding to various stimuli. These results provide a foundation for understanding CsCMLs and provide a theoretical basis for further study of the physiological functions of CsCMLs.


Assuntos
Cucumis sativus , Cucumis sativus/genética , Genoma de Planta/genética , Calmodulina/genética , Filogenia , Família Multigênica/genética
3.
Food Sci Nutr ; 9(9): 4963-4973, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34532008

RESUMO

Postharvest melatonin treatments have been reported to improve the quality and storability, especially to inhibit browning in many fruits, but the effect had not been systematically investigated on longan fruit. In this study, the effect of 0.4 mM melatonin (MLT) dipping on the quality and pericarp browning of longan fruits stored at low temperature was investigated. The MLT treatment did not influence the TSS content of longan fruits but lead to increased lightness and h° value while decreased a* value of pericarp. More importantly, the treatment significantly delayed the increase in electrolyte leakage and malonaldehyde accumulation, inhibited the activities of polyphenol oxidase and peroxidase, and thus retarded pericarp browning. In addition, the treatment significantly inhibited the production of O2 •- and H2O2 while promoted the accumulation of glutathione, flavonoids, and phenolics at earlier storage stages in longan pericarp. Interestingly, the activities of ascorbate peroxidase (APX) and superoxide dismutase (SOD) were significantly upregulated but activities of catalase were downregulated in the MLT-treated longan pericarp. MLT treatment effectively enhanced APX and SOD activities, increased flavonoid, phenolics, and glutathione content, protected cytomembrane integrity, inhibited the production of O2 •- and H2O2 and browning-related enzymes, and thus delayed the longan pericarp browning.

4.
Braz J Microbiol ; 52(2): 801-809, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33813730

RESUMO

Ectomycorrhizas play a fundamental role in the function of forest ecosystems, being essential for plant nutrition absorption and soil quality. Many afforestation and reforestation programmes have begun to recover and maintain coastal forests in China, using pine species including Pinus thunbergii. We investigated the ectomycorrhizal colonization status of P. thunbergii in coastal pine forests of the Yellow Sea of China. We identified a total of 53 ectomycorrhizal fungal species in 74 soil samples collected from three sites and found that Thelephoraceae (10 spp.) and Russulaceae (8 spp.) were the most species-rich ectomycorrhizal fungal lineages. Russula sp. 1 was the most abundant species, accounting for 15.3% of the total ectomycorrhizal tips identified. Most of the remaining species were rare. At this small scale, host identity had no significant effect on the ectomycorrhizal fungal community composition (A = 0.036, P = 0.258), but sampling sites did (A = 0.135, P = 0.041). In addition, Na+ and K+ content and soil pH had significant effects on the ectomycorrhizal fungal community. The ectomycorrhizal fungal community associated with different host plants will become an important new direction for research, as ectomycorrhiza may have the potential to improve host capacity to establish in salt-stressed environments. This will provide a theoretical basis and technical support for saline soil reforestation and rehabilitation using pine species with compatible, native ectomycorrhizal fungi in Yellow Sea coastal areas.


Assuntos
Florestas , Micobioma , Micorrizas/isolamento & purificação , Pinus/microbiologia , China , Concentração de Íons de Hidrogênio , Micorrizas/classificação , Micorrizas/genética , Oceanos e Mares , Potássio/análise , Solo/química , Microbiologia do Solo
5.
Telemed J E Health ; 26(10): 1291-1300, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31928505

RESUMO

Abstract Background/Introduction: The quality of maternal health care service is a crucial determinant of maternal morbidities and mortalities. This study aimed to explore feasibility and relative efficacy of WeChat (WC), of specialist team (ST) service, and of combined of both interventions (WC-ST) for improving the quality of maternal health care in China. Materials and Methods: A four-arm randomized controlled trial of 1,400 pregnant women was conducted in three hospitals in Chengdu, Southwest China, from December 2016 to October 2017. Eligible women were randomly assigned to either of three intervention groups or the control group (service as usual; SAU). Main outcome measures were satisfaction rate and uptakes of maternal health care service at 49 days postpartum based on questionnaire survey. Results: No significant differences in satisfaction rate were found among four groups at baseline (p = 0.981), and significant group differences were noted at 49 days postpartum (p < 0.001), with the highest rate from WC-ST group (98.6%), followed by that of ST (95.2%) and WC (91.6%) groups, and SAU group being the lowest (85.2%). The same pattern of group difference was observed in measures of health care uptake behaviors. Most health care uptake measures from the baseline to post-trial were significantly improved within each of the intervention groups, while most such measures in the control group were not different from baseline to post-trial. Discussion and Conclusions: The WC and ST service is feasible and potentially effective in improving the quality of maternal health care service in China. The study has revealed limitations and options for improvement in future main trial.


Assuntos
Saúde Materna , Período Pós-Parto , China , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Gravidez , Gestantes
6.
PLoS One ; 9(1): e85593, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465610

RESUMO

Because evapotranspiration (ET) is the second largest component of the water cycle and a critical process in terrestrial ecosystems, understanding the inter-annual variability of ET is important in the context of global climate change. Eight years of continuous eddy covariance measurements (2003-2010) in a subtropical coniferous plantation were used to investigate the impacts of climatic factors and ecosystem responses on the inter-annual variability of ET. The mean and standard deviation of annual ET for 2003-2010 were 786.9 and 103.4 mm (with a coefficient of variation of 13.1%), respectively. The inter-annual variability of ET was largely created in three periods: March, May-June, and October, which are the transition periods between seasons. A set of look-up table approaches were used to separate the sources of inter-annual variability of ET. The annual ETs were calculated by assuming that (a) both the climate and ecosystem responses among years are variable (Vcli-eco), (b) the climate is variable but the ecosystem responses are constant (Vcli), and (c) the climate is constant but ecosystem responses are variable (Veco). The ETs that were calculated under the above assumptions suggested that the inter-annual variability of ET was dominated by ecosystem responses and that there was a negative interaction between the effects of climate and ecosystem responses. These results suggested that for long-term predictions of water and energy balance in global climate change projections, the ecosystem responses must be taken into account to better constrain the uncertainties associated with estimation.


Assuntos
Mudança Climática , Ecossistema , Transpiração Vegetal/fisiologia , Traqueófitas/fisiologia , Biomassa , Dióxido de Carbono/metabolismo , China , Geografia , Chuva , Estações do Ano , Temperatura , Traqueófitas/classificação , Clima Tropical , Água/metabolismo
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 15(5): 343-7, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23676934

RESUMO

OBJECTIVE: To investigate influential factors for the tendency to medicate and medication compliance in children with attention deficit hyperactivity disorder (ADHD). METHODS: A total of 188 children aged from 5 to 16 years, who were initially diagnosed with ADHD according to DSM-IV criteria, were included in the study. They underwent symptom assessment and cognitive function test. The compliance of methylphenidate treatment was evaluated. RESULTS: Patients with better emotional state, and fewer oppositional and hyperactive behaviors and those who had a family history of psychiatric diseases and who obtained lower scores in the number cancellation test (NCT), were more prone to medication and/or exhibited better medication compliance. Logistic regression analysis showed that fewer oppositional and hyperactive behaviors and lower NCT scores were the predictive factors for a higher tendency to medicate, and a better emotional state was the predictive factor for better medication compliance. Patients of predominantly inattentive type were more prone to medication and showed better medication compliance, as compared with those of combined type. Gender, age and symptom severity were not associated with the tendency to medicate and/or medication compliance. CONCLUSIONS: There is a need to enhance medication compliance in children with ADHD who have hyperactive, impulsive and oppositional behaviors, and to improve their long-term social functions.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Adesão à Medicação , Metilfenidato/uso terapêutico , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Criança , Pré-Escolar , Emoções , Feminino , Humanos , Modelos Logísticos , Masculino
8.
Environ Monit Assess ; 185(1): 833-44, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22411032

RESUMO

The nitrogen (N) deposition fluxes were investigated in eight typical forest ecosystems along the North-South Transect of Eastern China (NSTEC; based on the ChinaFLUX network) by ion-exchange resin (IER) columns from May 2008 to April 2009. Our results demonstrated that the method of IER columns was both labor cost saving and reliable for measuring dissolved inorganic nitrogen (DIN) deposition at the remote forest stations. The deposition of DIN in the throughfall ranged from 1.3 to 29.5 kg N ha(-1) a(-1), increasing from north to south along NSTEC. The relatively high average ratio of ammonium to nitrate in deposition (1.83) indicated that the N deposition along the NSTEC in China mostly originated in farming and animal husbandry rather than in industry and vehicle activities. For seasonal variability, the DIN deposition showed a single peak in the growing season in the northern part of NSTEC, while, in the southern part, it exhibited double-peaks in the early spring and the mid-summer, respectively. On the annual scale, the DIN deposition variations of the eight sites could be mainly explained by precipitation and the distances from forest stations to provincial capital cities.


Assuntos
Poluentes Atmosféricos/análise , Ecossistema , Monitoramento Ambiental/métodos , Nitrogênio/análise , Árvores , Poluição do Ar/estatística & dados numéricos , China
9.
New Phytol ; 177(4): 927-937, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18069958

RESUMO

Carbon (C) and water cycles of terrestrial ecosystems are two coupled ecological processes controlled partly by stomatal behavior. Water-use efficiency (WUE) reflects the coupling relationship to some extent. At stand and ecosystem levels, the variability of WUE results from the trade-off between water loss and C gain in the process of plant photosynthetic C assimilation. Continuous observations of C, water, and energy fluxes were made at three selected forest sites of ChinaFLUX with eddy covariance systems from 2003 to 2005. WUE at different temporal scales were defined and calculated with different C and water flux components. Variations in WUE were found among three sites. Average annual WUE was 9.43 mg CO(2) g(-1) H(2)O at Changbaishan temperate broad-leaved Korean pine mixed forest, 9.27 mg CO(2) g(-1) H(2)O at Qianyanzhou subtropical coniferous plantation, and 6.90 mg CO(2) g(-1) H(2)O at Dinghushan subtropical evergreen broad-leaved forest. It was also found that temperate and subtropical forest ecosystems had different relationships between gross primary productivity (GPP) and evapotranspiration (ET). Variations in WUE indicated the difference in the coupling between C and water cycles. The asynchronous response of GPP and ET to climatic variables determined the coupling and decoupling between C and water cycles for the two regional forest ecosystems.


Assuntos
Ecossistema , Árvores/fisiologia , Água/metabolismo , Carbono/metabolismo , China , Clima , Estações do Ano
10.
Ann Bot ; 93(4): 435-41, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14980969

RESUMO

BACKGROUND AND AIMS: The stomata are a key channel of the water cycle in ecosystems, and are constrained by both physiological and environmental elements. The aim of this study was to parameterize stomatal conductance by extending a previous empirical model and a revised Ball-Berry model. METHODS: Light and CO(2) responses of stomatal conductance and photosynthesis of winter wheat in the North China Plain were investigated under ambient and free-air CO(2) enrichment conditions. The photosynthetic photon flux density and CO(2) concentration ranged from 0 to 2000 micro mol m(-2) s(-1) and from 0 to 1400 micro mol mol(-1), respectively. The model was validated with data from a light, temperature and CO(2) response experiment. RESULTS: By using previously published hyperbolic equations of photosynthetic responses to light and CO(2), the number of parameters in the model was reduced. These response curves were observed diurnally with large variations of temperature and vapour pressure deficit. The model interpreted stomatal response under wide variations in environmental factors. CONCLUSIONS: Most of the model parameters, such as initial photon efficiency and maximum photosynthetic rate (P(max)), have physiological meanings. The model can be expanded to include influences of other physiological elements, such as leaf ageing and nutrient conditions, especially leaf nitrogen content.


Assuntos
Dióxido de Carbono/farmacologia , Fotossíntese/fisiologia , Epiderme Vegetal/fisiologia , Triticum/fisiologia , Dióxido de Carbono/metabolismo , China , Simulação por Computador , Luz , Modelos Biológicos , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Epiderme Vegetal/efeitos dos fármacos , Epiderme Vegetal/efeitos da radiação , Temperatura , Triticum/efeitos dos fármacos , Triticum/efeitos da radiação
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