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Maintenance of intracellular ion balance, especially Na+ and K+, plays an important role in plant responses to salt stress. Vessels in xylem are responsible for long-distance ion transport in vascular plants. Knowledge on the salt stress response in woody plants in limited. In this study, we identified miR319a as an important regulator in respond to salt stress in poplar. miR319a overexpression transgenic poplar showed a salt-tolerant phenotype, and cytological observation showed reduced cambium cell layers, wider xylem, increased number and lumen area of vessels and fibers, and thinner cell wall thickness in the transgenics. The miR319a-MIMIC plants, meanwhile, had opposite phenotypes, with narrower xylem, reduced number and lumen area of vessels and fibers cells, and increased wall thickness. In addition, overexpression of miR319a driven by the vessel-specific promoter significantly improved the salt tolerance compared with the fiber-specific promoter. The expression levels of PagHKT1;2 and PagSKOR1-b, which encoded high-affinity K+ and Na+ transporters for Na+ efflux and K+ influx, respectively, were positively correlated with the vessel number and lumen area. These results suggest that miR319 not only promotes ion transport rates by increasing vessel number and lumen area and reducing cell wall thickness, but also regulates the concentrations of Na+ and K+ in the xylem by up-regulating PagHKT1;2 and PagSKOR1-b. We demonstrate that miR319 may coordinate the response of poplar to salt stress through both mechanisms, enriching our understanding of the synergistic effects of the secondary xylem structure and long-distance ion transport balance in the salt tolerance of poplar.
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RATIONALE: Ghost cell odontogenic carcinoma is a rare malignant odontogenic carcinoma characterized by the presence of ghost cells. It has a nonspecific clinical and radiographic presentation and can be locally destructive and invasive, sometimes with distant metastases. However, no effective systemic therapy is currently recommended for such patients. PATIENT CONCERNS: The patient has been unable to undergo surgery or radiotherapy again. Therefore, he was referred to our department for a more aggressive, multimodal systematic treatment program. DIAGNOSES: The histopathological examination was morphologically suggestive of ghost cell odontogenic carcinomas. INTERVENTIONS: We report a case of locally invasive primary inoperable odontogenic shadow cell carcinoma in a 31-year-old Chinese man who achieved treatment with Toripalimab and chemotherapy, followed by Toripalimab maintenance therapy after 6 cycles. OUTCOMES: He achieved partial remission after treatment. The quality of life significantly improved after treatment. There were no grade 3/4 treatment-related adverse events during treatment. LESSONS: This case presented that Toripalimab and chemotherapy may be a safe and effective systemic therapy for ghost cell odontogenic carcinoma.
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Carcinoma , Neoplasias Maxilomandibulares , Neoplasias de la Boca , Tumores Odontogénicos , Masculino , Humanos , Adulto , Calidad de Vida , Tumores Odontogénicos/diagnóstico , Tumores Odontogénicos/terapiaRESUMEN
PURPOSE: Citrate reaction is one of the main adverse events in peripheral blood mononuclear cell (MNC) collection. The aim of this study was to elucidate the risk factors for citrate reaction in patients with advanced solid tumor collection and to construct a nomogram to predict the risk. METHODS: One hundred forty-eight patients with advanced solid tumor who underwent peripheral blood MNC collection in our hospital between January 2021 to December 2021 were selected. The general data, creatinine level before collection, Ca2+ concentration before collection, absolute value of monocyte lymphocytes before collection, circulating blood volume, anticoagulant dosage, and blood collection duration were included in Logistic regression analysis to identify the risk factors of citrate reaction. According to the results of the multivariate logistic model, nomogram was established and receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of the model. RESULTS: Among the 148 solid tumor patients, 35 patients (23.6%) of the 148 patients developed citrate reaction. Multivariate analysis showed that the risk factors for citrate reaction in the process of collection included sex (odds ratio [OR] = 6.718; 95% confidence interval [95% CI]: 2.191-20.594, P = .001), age (OR = 0.957; 95% CI: 0.921-0.996, P = .03), and processed circulating blood volume (OR = 1.001; 95% CI: 1.000-1.002, P = .01). Logistic regression can analyze independent risk factors and establish risk prediction model. The predictive performance of the model is good, and the area under ROC curve is 0.799. CONCLUSIONS: The MNC collection process is safe. The incidence of citrate reaction in the collection of peripheral blood MNCs from patients with advanced solid tumor is related to the age, gender, and processed circulating blood volume of patients. The nomogram can be used to assess a patient's risk of citrate reaction.
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Neoplasias , Nomogramas , Humanos , Leucocitos Mononucleares , Ácido Cítrico/efectos adversos , Estudios Retrospectivos , Neoplasias/tratamiento farmacológico , CitratosRESUMEN
As a biosorbent, algae are frequently used for the biotreatment or bioremediation of water contaminated by heavy metal or radionuclides. However, it is unclear that whether or not the biomineralization of these metal or radionuclides can be induced by algae in the process of bioremediation and what the mechanism is. In this work, Ankistrodsemus sp. has been used to treat the uranium-contaminated water, and more than 98% of uranium in the solution can be removed by the alga, when the initial uranium concentration ranges from 10 to 80 mg/L. Especially, an unusual phenomenon of algae-induced uranium biomineralization has been found in the process of uranium bioremediation and its mineralization mechanism has been explored by multiple approaches. It is worth noticing that the biomineralization of uranium induced by Ankistrodsemus sp. is significantly affected by contact time and pH. Uranium is captured rapidly on the cell surface via complexation with the carboxylate radical, amino and amide groups of the microalgae cells, which provides nucleation sites for the precipitation of insoluble minerals. Uranium stimulates Ankistrodsemus sp. to metabolize potassium ions (K+), which may endow algae with the ability to biomineralize uranium into the rose-like compreignacite (K2[(UO2)6O4(OH)6]â¢8H2O). As the time increased, the amorphous gradually converted into compreignacite crystals and a large number of crystals would expand over both inside and outside the cells. To the best of our knowledge, this is the first investigated microalgae with a time-dependent uranium biomineralization ability and superior tolerance to uranium. This work validates that Ankistrodsemus sp. is a promising alga for the treatment of uranium-contaminated wastewater.
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Chlorophyta , Uranio , Amidas , Biomineralización , Minerales/química , Potasio , Radioisótopos , Uranio/química , Compuestos de Uranio , Aguas Residuales , AguaRESUMEN
Dyslexia is a disorder characterized by an impaired ability to understand written and printed words or phrases. Epidemiological longitudinal data show that dyslexia is highly prevalent, affecting 10-20% of the population regardless of gender. This study aims to provide a detailed overview of research status and development characteristics of dyslexia from types of articles, years, countries, institutions, journals, authors, author keywords, and highly cited papers. A total of 9,166 publications have been retrieved from the Social Sciences Citation Index (SSCI) and Science Citation Index Expanded (SCI-E) from 2000 to 2021. The United States of America, United Kingdom, and Germany were the top three most productive countries in terms of the number of publications. China, Israel, and Japan led the Asia research on dyslexia. University of Oxford had the most publications and won first place in terms of h-index. Dyslexia was the most productive journal in this field and Psychology was the most used subject category. Keywords analysis indicated that "developmental dyslexia," "phonological awareness," children and fMRI were still the main research topics. "Literacy," "rapid automatized naming (RAN)," "assessment," "intervention," "meta-analysis," "Chinese," "executive function," "morphological awareness," "decoding," "dyscalculia," "EEG," "Eye tracking," "rhythm," "bilingualism," and "functional connectivity" might become the new research hotspots.
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Bibliometría , Dislexia , Asia , Niño , China , Humanos , Reino Unido , Estados UnidosRESUMEN
The important role of microbes in the biomineralization and migration behavior of uranium in the field of environmental chemistry has been well emphasized in previous work. However, limited work on mineralization processes of indigenous microorganism has prevented us from a deeper understanding of the process and mechanisms of uranium biomineralization. In this work, the dynamic process and mechanism of uranium biomineralization in Enterobacter sp. X57, a novel uranium-tolerant microorganism separated from uranium contaminated soil, were systematically investigated. Enterobacter sp. X57 can induce intracellular mineralization of U (VI) to Uramphite (NH4UO2PO4·3H2O) under neutral conditions by alkaline phosphatase. In this biomineralization process, soluble U (VI) first bonded with the amino and phosphate groups on the plasma membrane, providing initial nucleation site for the formation of U (VI) biominerals. Then the impairment of cell barrier function and the enhancement of alkaline phosphatase metabolism occurred with the accumulation of uranium in cells, creating a possible pathway for soluble U (VI) to diffuse into the cell and be further mineralized into U (VI)-phosphate minerals. All the results revealed that the intracellular biomineralization of uranium by Enterobacter sp. X57 was a combined result of biosorption, intracellular accumulation and phosphatase metabolism. These findings may contribute to a better understanding of uranium biomineralization behavior and mechanism of microorganisms, as well as possible in-situ bioremediation strategies for uranium by indigenous microorganisms.
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Uranio , Fosfatasa Alcalina/metabolismo , Biodegradación Ambiental , Biomineralización , Enterobacter/metabolismo , Fosfatos/metabolismo , Uranio/químicaRESUMEN
To confront college students' new reading patterns and the continuous decline in academic library borrowing rates, we conducted empirical research on promoting multisensory reading as a way to attract students' attention, and to stimulate interest in, and promote the practice of, reading through a library program called "Reading Today Listening Everyday" (RTLE) on a library's WeChat public account. The program involved 48 librarians and 105 students who were recruited into different groups to co-create, edit and release multisensory tweets every workday. Multisensory contents including text-based content, audio-based content and emotional resonance were presented to evoke readers' visual, audio, and emotional senses to induce more reading practice. Using the Context, Input, Process and Product (CIPP) evaluation method, the multisensory presentation in RTLE program was proven to be effective in promoting library reading with a high number of tweeted page views and an increased borrowing rate for recommended books. In 2020, 269 issues accompanied by 269 audio frequencies garnered 80,268 page views, depending on the caliber of the reading promoter out of the 48 librarians and 52 student anchors behind it. The 484 RTLE-recommended books were borrowed 113 times in 2020, which was a rate 1.46 times higher than in 2019 (77 times). The analysis of the relationship between tweet views and borrowing rates for recommended books indicates that more page views indicate greater reader interest, leading to increased borrowing. From readers' feedback and comments, the gain afforded by multisensory reading can improve higher-level reading trends such as the number of reading interests, enjoyment, engagement, etc.
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It is of great significance to develop convenient methods and low-cost materials to remove uranium from wastewater. Ankistrodesmus sp., an easy growing green alga, was employed for highly efficient removal of uranium from aqueous solution. The biosorption results under different experimental condition indicate that the alga possess outstanding uranium adsorption ability (qmax = 601.2 mg g-1). Moreover, Ankistrodesmus sp. could be effectively regenerated with hydrochloric acid solution (0.1 M) and used again for uranium adsorption. Even in simulated mine water with various coexisting ions, Ankistrodesmus sp. also exhibits high removal efficiency (95.6%) towards uranium. Furthermore, the adsorption behavior of uranium by alga could be described in the Freundlich isotherms model and the adsorption process was consistent with the pseudo-second-order kinetics model. The characteristic of Fourier transform infrared spectrum, scanning electron microscopy, transmission electron microscope and X-ray photoelectron spectroscopy reveal that -NH2, -COOH, -CONH2 and C-O groups have participated in biosorption process. Therefore, complexation, electrostatic adsorption and ions exchange are the dominated action of uranium biosorption in the algae. All findings in this work suggest that Ankistrodesmus sp. can be a promising candidate for the effective and practical application in field of disposed uranium contamination.
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Microalgas , Uranio , Concentración de Iones de Hidrógeno , Polvos , Espectroscopía Infrarroja por Transformada de Fourier , Uranio/análisis , Aguas ResidualesRESUMEN
[This corrects the article DOI: 10.3389/fpls.2021.695223.].
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Lignin is one of the major components of xylem cell walls in tree stems. The lignin in the wood of most flowering plants (dicotyledonous angiosperms) is typically polymerized from three monolignol precursors, coniferyl alcohol, sinapyl alcohol, and p-coumaroyl alcohol, resulting in guaiacyl (G), syringyl (S), and hydroxyphenyl (H) subunits, respectively. In this study, we focus on the transcriptional regulation of a coniferaldehyde 5-hydroxylase (CAld5H2) gene, which encodes a key enzyme for sinapyl alcohol biosynthesis. We carried out a yeast one-hybrid (Y1H) screen to identify candidate upstream transcription factors (TFs) regulating CAld5H2. We obtained 12 upstream TFs as potential regulators of CAld5H2. One of these TF genes, BLH6a, encodes a BEL1-like homeodomain (BLH) protein and negatively regulated the CAld5H2 promoter activity. The direct regulation of CAld5H2 promoter by BLH6a was supported by chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR) and dominant repression of BLH6a in transgenic plants. Luciferase complementation imaging analyses showed extensive protein-protein interactions among these 12 TFs. We propose that BLH6a is a negative regulator of CAld5H2, which acts through combinatorial regulation of multiple TFs for sinapyl alcohol (S monolignol) biosynthesis in poplar.
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Diet is an important factor in shaping and influencing both an insect's phenotype and gut bacterial community, which commonly establishes diversely symbiotic interactions with the host. Efforts to leverage the connection between diet, insects, and gut microbiome primarily focus on how diet alters insect's phenotype or gut microbial composition and relatively few studies have illuminated the link between the diet-induced insect phenotypic difference and variation of gut microbiota. Mirids bugs, Adelphocoris suturalis, are plant sap-feeding omnivores that sometimes complementarily prey on other insects, like aphids (the dietary regime is referred to hereafter as balanced diet). In this study, we found that an imbalanced diet (exclusive ingestion of aphids) induced significantly higher mortality in A. suturalis (86.66%). Further gut microbial community analysis showed that the dietary difference significantly changed both the abundance and composition of the bug's gut microbiome. Most notably, an abundance of entomopathogenic Serratia bacteria in the A. suturalis gut was positively correlated with the proportion of aphids in A. suturalis diet, and Serratia marcescens was found to transfer into the hemocoels of carnivorous bugs. Injection of S. marcescens to the hemocoels further confirmed its detrimental effect to the bugs. Collectively, our study suggests that the diet-altered variation of gut microbiota may be detrimental to host insect, advancing the knowledge of omnivorous insects' strategy in forage allocation of different foods.
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Microbioma Gastrointestinal , Microbiota , Animales , Bacterias/genética , Dieta , ARN Ribosómico 16SRESUMEN
BACKGROUND: Herbal formula Gegen-Qinlian Decoction (GQD) has been widely used in China for the treatment of type 2 diabetes mellitus (T2DM), but its efficacy and safety are unclear. METHOD: The studies were identified from the PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure database, Wanfang database, and VIP database using the keywords "Gegenqinlian" or "Gegen-Qinlian" or "Gegen-Qin-Lian" or "Ge Gen Qin Lian." Relevant studies were selected according to predefined inclusion and exclusion criteria. Study selection, data extraction, and validation were carried out by, at least, two reviewers with disagreements being settled by discussion. RESULTS: After literature search, a total of 26 randomized controlled trials were included with a total of 2553 patients. There was evidence that compared with metformin, the combination of GQD and metformin significantly reduced the fasting plasma glucose levels (MD -1.79, 95% CI (-2.31, -1.27), p < 0.00001); 2-hour postprandial plasma glucose levels (MD -1.72, 95% CI (-2.12, -1.31), p < 0.00001); and glycosylated hemoglobin levels (MD -1.26, 95% CI (-1.80, -0.72), p < 0.00001), and no serious side effects were identified. CONCLUSION: These data suggest that GQD may be an effective herbal formula in treating T2DM without serious side effects. The addition of GQD also enhances the hypoglycemic effects of metformin. However, the evidence remains weak due to methodological flaws, which may amplify the therapeutic benefit of GQD.
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OBJECTIVE: To investigate the protective effect of repaglinide on rat with atherosclerosis. METHODS: Sprague Dawley (SD) rats were divided into control, model, repaglinide, and metformin groups. In addition to the normal group, rats were given intraperitoneal injection of streptozotocin and high-fat diet (HFD). Meanwhile, repaglinide or metformin was administrated to the treatment rats, respectively, for 4 weeks. Serum, plasma, liver, epididymal fat, and aorta thoracica were obtained to observe the protective effect of repaglinide on rat with atherosclerosis. RESULTS: Compared to the control group, blood glucose was increased in the model group (P < .05), while it was decreased in the drug-administered groups. In addition, the levels of endothelin 1, TG, TC, low-density lipoprotein cholesterol, atherogenic index, liver index, and epididymal fat index were significantly increased, but the levels of high-density lipoprotein cholesterol, plasminogen activator inhibitor 1, and antiatherogenic index were decreased significantly in the model group compared to the control group (P < .05, respectively). And these effects were reversed by treatment with repaglinide (P < .05, respectively). CONCLUSION: Our results suggested that repaglinide may regulate the formation of early atherosclerosis through the abovementioned mechanisms.
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Apolygus lucorum (Meyer-Dür) is a destructive pest to >280 plants. Major economic significance and pesticide resistance issues have created a need for integrated pest management (e.g., RNAi, entomopathogen-based bioinsecticides) for A. lucorum. To better develop these control strategies, large-scale genetic studies involving gene-expression analysis are required and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is the most commonly used method. However, there have been no reports on appropriate reference genes in A. lucorum. Here, we evaluated nine widely utilized reference genes including EF1γ, RPL32, RPL27, SDH, TBP, ACT, ACT2, GAPDH, and ßTUB for their expression stabilities in A. lucorum under five different conditions i.e., life stage, tissue, sex, dsRNA injection, and entomopathogen infection. Based on the gene stability ranking calculated by RefFinder, which integrates four algorithms (geNorm, delta Ct method, NormFinder, and BestKeeper), we recommend RPL27 and RPL32 as the most appropriate reference genes for molecular studies in different life stages and tissues; GAPDH and EF1γ for different sexes and entomopathogen infection studies; and RPL27 and EF1γ for RNAi studies. The results of this study will help improve the accuracy and reliability for normalizing the RT-qPCR data for further molecular analysis in A. lucorum.
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Heterópteros , Animales , Perfilación de la Expresión Génica , Plantas , Interferencia de ARN , Reacción en Cadena en Tiempo Real de la Polimerasa , Estándares de Referencia , Reproducibilidad de los ResultadosRESUMEN
DNA methylation and histone modification are important epigenetic marks that coregulate gene expression and genome stability. To identify factors involved in chromatin silencing, we carried out a forward genetic screen for mutants that release the silenced Pro-35S:LUCIFERASE (35SP-LUC) in Arabidopsis (Arabidopsis thaliana). We identified an epigenetic regulator, METHIONINE SYNTHASE1 (ATMS1), which catalyzes the synthesis of methionine (Met) in the one-carbon metabolism pathway. The ATMS1 mutation releases the silenced 35SP-LUC and the majority of endogenous genes and transposons. The effect of ATMS1 on chromatin silencing is related to decreased levels of DNA methylation (CG, CHG, and CHH) and histone-3 lysine-9 dimethylation. The ATMS1 mutation caused a significant decrease in the ratio of S-adenosylmethionine to S-adenosylhomocysteine. Exogenous application of Met rescued the phenotype of atms1-1 ATMS1 plays a predominant role in DNA and histone methylations among the three Met synthetase homologs. These results suggest that ATMS1 is required for DNA and histone methylations through its function in the one-carbon metabolism pathway, indicating the complex interplay between metabolism and epigenetic regulation.
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5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Epigénesis Genética , Histonas/metabolismo , Procesamiento Proteico-Postraduccional , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Metilación de ADN , Silenciador del Gen , Lisina/metabolismo , Metionina/metabolismoRESUMEN
To compare KnockOut serum replacement (KSR) and fetal bovine serum (FBS) for the development of germ cells. Testicular tissues from Sprague-Dawley rats were cultured for 4 weeks in culture media supplemented with FBS or KSR. Tissue area was measured at the beginning and end of the culturing period. Testicular histology, development of the germ cells, and the diameter of seminiferous tubules were analyzed by hematoxylin and eosin staining. After 4 weeks in culture, apoptosis and expression of the stage-specific spermatogenesis marker genes Kit, Sycp3, and Crisp1 were assayed. Tissues cultured in KSR-supplemented media were able to sustain growth and gradually increase seminiferous tubule diameter during the culture period. In addition, spermatogonia, primary spermatocytes, secondary spermatocytes, and round spermatids were observed after 4 weeks in culture, and reverse transcription-PCR confirmed expression of the marker genes. In comparison, tissues cultured in FBS-supplemented media showed dwindling testicular organization, necrotic seminiferous tubules, and expression of Kit, but inconsistent expression of Sycp3 and Crisp1 KnockOut serum replacement outperforms FBS as a growth media supplements for culturing immature spermatogonial tissue culture.
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Medios de Cultivo , Suero , Espermatozoides/crecimiento & desarrollo , Testículo/citología , Técnicas de Cultivo de Tejidos , Animales , Apoptosis , Bovinos , Sangre Fetal , Expresión Génica , Masculino , Ratas , Ratas Sprague-Dawley , Túbulos Seminíferos/anatomía & histología , Espermátides/citología , Espermatocitos/citología , Espermatogénesis/genética , Espermatogonias/citología , Testículo/crecimiento & desarrolloRESUMEN
Recently, three types of cavitation: (i) expanding gradually; (ii) expanding-exploding, becoming a long-shaped bubble-lengthening by degrees; (iii) suddenly exploding and fully filling the conduit instantly, were proposed. Directed by this theory, experiments were performed using light microscopy to study the natural drying processes of xylem sections of Platycladus orientalis (L.) Franco. Three different phenomena of gas filling process in conduits were captured by replaying recorded videos. The first phenomenon is that a bubble emerging in a conduit expands and elongates gradually to fill the conduit. The second phenomenon is that a bubble emerging in a conduit expands gradually, and then suddenly becomes long-shaped, and extends continuously. The third phenomenon is that a bubble instantly fully fills a conduit. This paper suggests in these experiments that after losing the bulk water of a section, as the water stress of that section became more severe, the water pressures of different conduits of the section were not necessarily the same, and as time went on, the water pressures decreased constantly. Considering some practical factors, the three phenomena captured in our experiment are explained by our theory.
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Cupressaceae/fisiología , Microscopía , Agua/fisiología , Xilema/fisiología , DesecaciónRESUMEN
KEY MESSAGE: Trade-off in dioecious plant. The trade-off between reproduction, vegetative growth and maintenance is a major issue in the life history of an organism and a record of the process which is producing the largest possible number of living offspring by natural selection. Dioecious species afford an excellent opportunity for detecting such possible trade-offs in resource allocation. In this study, we selected the dioecious shrub Acer barbinerve to examine possible trade-offs between reproduction and vegetative growth in both genders at different modular levels during three successive years. Reproductive and vegetative biomass values were assessed during successive years to evaluate their intra-annual and inter-annual trade-offs. These trade-offs were examined at shoot, branch and shrub modular levels in Acer barbinerve shrubs. An intra-annual trade-off was detected at the shoot level for both genders in 2011 and 2012. Both males and females showed a negative correlation between reproduction and vegetative growth, but this was more prominent in males. For the females of the species, inter-annual trade-offs were only found at branch and shrub levels. Slightly negative correlations in females were detected between the reproduction in 2012 and the reproduction in the two previous years. The gender ratio was significantly male biased during the three successive years of our investigation. Females had higher mortality rates in the larger diameter classes, both in 2011 and 2012. This study revealed a clear trade-off between reproduction and vegetative growth in Acer barbinerve, but results varied between males and females. The degree of autonomy of the different modular levels may affect the ability to detect such trade-offs.
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Acer/crecimiento & desarrollo , Reproducción , Acer/genética , Acer/fisiología , Biomasa , China , Ecosistema , Células Germinativas de las Plantas/crecimiento & desarrollo , Células Germinativas de las Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , TemperaturaRESUMEN
There are different opinions of the dynamics of an air bubble entering a xylem conduit. In this paper, we present a thorough mechanical analysis and conclude that there are three types of cavitation caused by air seeding. After an air seed enters a conduit at high xylem pressure P'(1), along with the drop of the water potential, it will expand gradually to a long-shaped bubble and extend continually. This is the first type of air seeding, or the type of expanding gradually. When the xylem pressure is moderate, right after an air seed enters a conduit, it will expand first. Then, as soon as the pressure reaches a threshold the bubble will blow up to form a bubble in long shape, accompanied by acoustic (or ultra-acoustic) emission. It will extend further as xylem pressure decreases continually. This is the second type of air seeding, or the type of expanding-exploding, becoming a long-shaped bubble-lengthening by degrees. In the range of P'(1) ≤ - 3P(o) (P(o) is atmospheric pressure), soon after an air seed is sucked into a conduit it will explode immediately and the conduit will be full of the gas of the bubble instantly. This is the third type of air seeding, or the type of sudden exploding and filling conduit instantly. The third type is the frequent event in daily life of plant.