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Cyclin-dependent kinase 5 (CDK5) is a member of cyclin-dependent kinase family, which does not directly regulate cell cycle. Through phosphorylation of target protein, CDK5 plays an irreplaceable role in the development, reparation and degeneration of neurons. Brain injury refers to the organic injury of brain tissue caused by external force hit on the head. Owing to the stress and repair system activated by our body itself after injury, various proteins and enzymes of the brain tissues are changed quantitatively, which can be used as indicators for estimating the time of injury. This review summarizes the progress on the distribution, the activity mechanism and the physiological effects of CDK5 after brain injury and its corresponding potential served as a marker for brain injury determination.
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Lesões Encefálicas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Fármacos Neuroprotetores/farmacologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Quinase 5 Dependente de Ciclina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios , Fosforilação/efeitos dos fármacos , Fatores de TempoRESUMO
OBJECTIVE: To study the expression of p35 and p25 in rat after focal cerebral contusion and to provide experimental data for estimating brain injury time. METHODS: Fifty adult male SD rats were randomly divided into 0 h, 6 h, 12 h, 24 h, 3 d, 5 d, 7 d, 10 d after focal cerebral contusion, control and sham-operated groups (5 rats each group). The focal cerebral contusion rat model was established. The expression of p35 and p25 protein of the damage peripheral zone in brain were detected by HE staining, immunohistochemistry and Western blotting at different injury time. RESULTS: A large number of p35 protein and a small amount of p25 protein were expressed in control group and sham-operated group. After focal cerebral contusion, p35 presented unimodal change with time and p25 presented bimodal changes with time. CONCLUSION: Expression of p35 and p25 showed different regularity with good time correlation, which could help to estimate the brain injury time.
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Lesões Encefálicas/metabolismo , Contusões/metabolismo , Fosfotransferases/metabolismo , Animais , Western Blotting , Encéfalo , Isquemia Encefálica , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Coloração e RotulagemRESUMO
Yutu-2 rover conducted an exciting expedition on the 41st lunar day to investigate a fin-shaped rock at Longji site (45.44°S, 177.56°E) by extending its locomotion margin on perilous peaks. The varied locomotion encountered, especially multi-form wheel slippage, during the journey to the target rock, established unique conditions for a fin-grained lunar regolith analysis regarding bearing, shear and lateral properties based on terramechanics. Here, we show a tri-aspect characterization of lunar regolith and infer the rock's origin using a digital twin. We estimate internal friction angle within 21.5°-42.0° and associated cohesion of 520-3154 Pa in the Chang'E-4 operational site. These findings suggest shear characteristics similar to Apollo 12 mission samples but notably higher cohesion compared to regolith investigated on most nearside lunar missions. We estimate external friction angle in lateral properties to be within 8.3°-16.5°, which fills the gaps of the lateral property estimation of the lunar farside regolith and serves as a foundational parameter for subsequent engineering verifications. Our in-situ spectral investigations of the target rock unveil its composition of iron/magnesium-rich low-calcium pyroxene, linking it to the Zhinyu crater (45.34°S, 176.15°E) ejecta. Our results indicate that the combination of in-situ measurements with robotics technology in planetary exploration reveal the possibility of additional source regions contributing to the local materials at the Chang'E-4 site, implying a more complicated geological history in the vicinity.
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Adopting atomic absorption spectrometry (novAA400), the present study investigated the distribution characteristics of soil cadmium (Cd) in different textured paddy soil profiles under rice-wheat rotation and its correlation with Cd uptake by rice and wheat in Chengdu Plain through repeatedly taking soil and plant samples at the fixed sites in the field. The results revealed that Cd in the paddy soil profiles was mainly concentrated at the plough layer (0-15 cm) that obviously featured 'Cd accumulates towards the rooting layer'. Soil total Cd and available Cd (1 mol x L(-1) MgCl2 extraction) in the profile declined with soil depths and its average values at 30-45 cm only accounted for 47.60% and 39.49% of those at 0-15 cm. The potential downward movement of Cd in the different textured soil profiles was observed as sandy loam > heavy loam > loam. There was no significant correlation between soil pH and available Cd(r = - 0.46) at 0-15 cm soil depth, while significantly negative correlations between soil pH and available Cd were observed at 15-30 cm (r = -0.78) and 30-45 cm (r = -0.86). The results further demonstrated that the Cd contents in either grain or straw of rice and wheat were not well correlated with soil total Cd at any soil depth (r = -0.092-0.383 for rice and r = 0.174-0.424 for wheat), but significantly correlated with soil available Cd at 0-15 cm and at 15-30 cm (r = 0.766*-0.953**) despite insignificant correlation at 30-45 cm (r = 0.526-0.584). It is strongly suggested that the soil available Cd can be used as a better criterion than the total soil Cd to rate Cd contaminated soils in relation to safety of agricultural products.
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Cádmio/análise , Produtos Agrícolas/crescimento & desenvolvimento , Poluentes do Solo/análise , Solo/química , Espectrofotometria Atômica/métodos , China , Monitoramento Ambiental , Oryza/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimentoRESUMO
Chronic kidney disease (CKD) is an ongoing deterioration of renal function that often progresses to end-stage renal disease. In this study, we aimed to screen and identify potential key genes for CKD using the weighted gene coexpression network (WGCNA) analysis tool. Gene expression data related to CKD were screened from GEO database, and expression datasets of GSE66494 and GSE62792 were obtained. After discrete analysis of samples, WGCNA analysis was performed to construct gene coexpression module, and the correlation between the module and disease was calculated. The modules with a significant correlation with the disease were selected for Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Then, the interaction network of related molecules was constructed, and the high score subnetwork was selected, and the candidate key molecules were identified. A total of 882 DEGs were identified in the screening datasets. A subnetwork containing 6 nodes was found with a high score of 12.08, including CEBPZ, IFI16, LYAR, BRIX1, BMS1, and DDX18. DEGs could significantly differentiate CKD and healthy individuals in principal component analysis. In addition, the MEturquiose, MEred, and MEblue in group were significantly correlated with disease in WGCNA. These 6 hub genes were found to significantly discriminate between CKD and healthy controls in the validation dataset, suggesting that they could use these molecules as candidate markers to distinguish CKD from healthy people. Overall, our study indicated that 6 hub genes may play key roles in the occurrence and development of CKD.
Assuntos
Perfilação da Expressão Gênica , Insuficiência Renal Crônica , Biomarcadores/metabolismo , Proteínas de Ligação a DNA/genética , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Proteínas Nucleares/genética , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/genéticaRESUMO
OBJECTIVE: To investigate Homer protein expression after focal brain contusion and explore the relationship between expression and injury time. METHODS: Focal brain contusion in rats was established and Homer protein expression in brain at different injury intervals after contusion was detected by immunohistochemistry and Western blotting. RESULTS: A small amount of Homer positive expression cells were detected in control group, sham operated group and experimental group (0.5 h after contusion). The amount of Homer positive expression cells increased after 3 h and reached peak 12 h after contusion. The amount of positive cells continued to decrease 1 d after contusion and to the base level 7 d after contusion. Homer protein expression based on immunohistochemistry and Western blotting had statistical difference among adjacent groups. CONCLUSION: Expression of Homer protein near the focal contusion area shows time dependence after brain contusion in rats.
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Lesões Encefálicas/metabolismo , Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Contusões/metabolismo , Animais , Western Blotting , Encéfalo/patologia , Lesões Encefálicas/patologia , Contusões/patologia , Modelos Animais de Doenças , Patologia Legal , Proteínas de Arcabouço Homer , Imuno-Histoquímica , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Coloração e Rotulagem , Fatores de TempoRESUMO
China produces half of the world's vegetables. The production uses 1.7% of the global harvest area of crops but accounts for 7.8% of the chemical fertilizers and 6.6% of crop-sourced greenhouse gas (GHG) emissions worldwide. Using an innovative management programme, the integrated knowledge and products strategy (IKPS), we demonstrate opportunities for producing more vegetables with lower environmental impacts in China's vegetable production systems. Combining soil-crop system management practices with enhanced-efficiency fertilizer products, IKPS was tested through 54 site-year field experiments in China's major agro-ecological zones by a national research network over 12 years. Compared with current farming practices, the adoption of IKPS decreased the nitrogen (N) application rate by 38%, N surplus by 65% and GHG emissions by 28%, while increasing yield by 17%. Scenario analyses showed that adoption of IKPS in China's vegetable production could mitigate resource and environmental burdens while enhancing food and nutrition security.
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Current evidence is controversial in the association between peripheral lymphocyte levels and the progression and mortality of Corona Virus Disease 2019 (COVID-19), and this meta-analysis aimed to clarify the association. A systematic search was conducted in public databases to identify all relevant studies, and the study-specific odds ratio (OR) and 95% confidence intervals (CI) were pooled. Finally, 16 studies were identified with a total of 1,873 progressive COVID-19 cases and 5,177 stable COVID-19 cases. In COVID-19 progression, lymphocyte levels showed a significant negative correlation (OR: 0.68, 95% CI: 0.51-0.89), but it was not significant in the subsets of CD3+ T cells (OR: 0.97, 95% CI: 0.93-1.02), CD4+ T cells (OR: 0.93, 95% CI: 0.80-1.08), CD8+ T cells (OR: 0.96, 95% CI: 0.92-1.00), B cells (OR: 0.98, 95% CI: 0.92-1.04), or NK cells (OR: 0.80, 95% CI: 0.61-1.04). In COVID-19 mortality, lymphocyte levels showed a significant negative correlation (OR: 0.41, 95% CI: 0.20-0.85), but it was not significant in the subsets of CD3+ T cells (OR: 0.95, 95% CI: 0.86-1.05), CD4+ T cells (OR: 1.06, 95% CI: 0.86-1.31), CD8+ T cells (OR: 0.38, 95% CI: 0.14-1.01), B cells (OR: 0.98, 95% CI: 0.92-1.04), or NK cells (OR: 0.80, 95% CI: 0.61-1.04). In conclusion, current evidence suggests a significant negative association of peripheral lymphocyte levels with COVID-19 progression and mortality, but it was not significant in the subsets of CD3+ T cells, CD4+ T cells, CD8+ T cells, B cells, and NK cells.
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Pot experiment was carried out to investigate the influence of nano zeolite (NZ) and ordinary zeolite (OZ) on the growth, activities of antioxidant enzyme, Cd fraction and Cd concentration in two varieties of Chinese cabbage. The results showed that the activities of SOD, CAT and POD in the shoot and root of two varieties increased, and the dry weight of shoot and the total dry weight of Chinese cabbage increased by 4.5%-96.5% and 3.4%-88.4%, respectively. The application of zeolite effectively reduced the Cd concentration of shoot and root in the two varieties of Chinese cabbage, and the reduction range increased with the increase of the application amount of zeolite. Under the low Cd condition (1mg·kg-1 Cd), the Cd concentration of edible parts (shoots) in SD4 variety and XJC3 variety decreased by 1.0%-75.0% and 19.5%-68.9% (except the Cd1+OZ5/OZ10 processing), respectively. Under the high Cd condition (5 mg·kg-1 Cd), the Cd concentration of the edible parts (shoots) in SD4 variety and XJC3 variety decreased by 7.2%-53.2%(except Cd5+OZ10 processing) and 0.7%-63.0%, respectively. The Cd concentrations of the edible parts (shoots) in tow varieties of Chinese cabbage in the nano zeolite treatments decreased by 10.5%-65.7% compared with the ordinary zeolite treatments. In Cd contaminated soils (1 mg·kg-1 and 5 mg·kg-1 Cd),) the total extraction amount of Cd in the edible parts (shoots) of SD4 variety reduced by 12.4%-68.8% and 13.2%-55.6% (except of Cd5+OZ5 processing), and the total extraction amount of Cd in the edible parts (shoots) of XJC3 variety reduced by 9.4%-71.5% and 3.1%-38.7% (except of Cd1+OZ5 processing), respectively. The application amount of nano zeolite (NZ) and ordinary zeolite (OZ) was more, the reduction range of the total extraction amount of Cd in the edible parts (shoots) of two varieties of Chinese cabbage was greater.
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Brassica/crescimento & desenvolvimento , Cádmio/análise , Nanopartículas , Poluentes do Solo/análise , Zeolitas , Antioxidantes/metabolismo , Brassica/enzimologia , Raízes de Plantas/enzimologia , Raízes de Plantas/crescimento & desenvolvimentoRESUMO
Soil incubation experiment and pot experiment were carried out to investigate the influence of nano zeolite (NZ) and ordinary zeolite (OZ) on the soil pH, cation exchange capacity, concentration of soil Cd, soil Cd fraction and Cd uptake by Chinese cabbage when exposed to different Cd pollution levels(1, 5, 10 and 15 mg·kg-1). The results of soil incubation experiment showed that the nano zeolite and ordinary zeolite dose(5, 10 and 20 g·kg-1) increased the soil pH and cation exchange capacity, and decreased the concentration of soil exchangeable Cd, while increased the concentration of Cd in carbonate, Fe-Mn oxide, organic matter and residual fraction. The lowest EX-Cd was observed in the high nano zeolite (20 g·kg-1) treatment. The soil pH and cation exchange capacity was extremely negatively correlated with the concentration of soil exchangeable Cd(P<0.01),and extremely positively correlated with the concentration of soil Fe-Mn oxide Cd(P<0.01). The results of pot experiment showed that the FDC of exchangeable Cd in soil decreased by 6.4%-63.2%, and the FDC of water-extractable and ethnol-extractable Cd in Chinese cabbage decreased by 2.1%-56% and 11.8%-100% with zeolite application, respectively. Moreover, the reduction effect of nano zeolite on Cd concentration in soil and plant was better than that of ordinary zeolite. The FDC of Cd fraction in shoot of Chinese cabbage showed correlation with the FDC of carbonate Cd and organic matter Cd in soil(P<0.05) when exposed to 1 mg·kg-1 Cd pollution. Moreover, correlation was also found in the FDC of organic matter Cd and residual Cd in soil(P<0.05) under 5 mg·kg-1 Cd pollution.
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Brassica/química , Cádmio/análise , Poluentes do Solo/análise , Solo/química , Zeolitas , Concentração de Íons de HidrogênioRESUMO
Incubation experiments were carried out to investigate the influence of different nano zeolite(NZ) and ordinary zeolite(OZ) levels(0, 5, 10 and 20 g·kg-1) on the fraction distribution coefficient (FDC) of Cd and soil CEC at different soil pH (4, 5, 6, 7 and 8) when exposed to different cadmium(Cd) levels(1, 5, 10 and 15 mg·kg-1), and pot experiment were carried out to investigate the effects of nano zeolite(NZ) and ordinary zeolite(OZ) on the growth, Cd concentration and Cd accumulation of Chinese cabbage. The results showed that nano zeolite and ordinary zeolite decreased the concentration and FDC of exchangeable Cd (EX-F), and increased the concentration and FDC of carbonate(CAB-F), Fe-Mn oxide(FMO-F), organic matter (OM-F) and residual fraction(RES-F) in incubation experiments. At the end of incubation, the FDC of soil exchangeable Cd decreased from 72.0%-88.0% to 2.4%-10.7%. The decreasing effect of zeolite on the concentration and FDC of exchangeable Cd (EX-F) increased with the increase of zeolite, and the decreasing effect of nano zeolite (NZ) was better than that of ordinary zeolite (OZ). During the culture of 28 d, the concentration of different Cd fractions in soil was in order of EX-F>RES-F>FMO-F>CAB-F>OM-F under different pH conditions. Exchangeable fraction Cd was the dominant fraction of Cd in soil during the whole incubation. Soil CEC had significant negative correlation with soil exchangeable Cd (EX-F) (P<0.01), and significant positive correlation with the concentrations of Fe-Mn oxide(FMO-F) and organic matter (OM-F) in soil(P<0.01). Nano zeolite and ordinary zeolite effectively increased soil CEC, and soil CEC increased with the increase of the pH value of soil in the zeolite treatments. Significant negative correlation was found in soil pH with soil exchangeable Cd (EX-F)(P<0.01). The dry weight of plant tissues in Chinese cabbage increased by 14.3%-131.4% in the presence of nano zeolite(NZ) and ordinary zeolite(OZ), and Cd concentration of shoot and root decreased by 1.0%-75.0% and 3.8%-53.2%, respectively. Higher concentration and accumulation of Cd were observed in XJC3 variety than those in SD 4 variety. Compared with ordinary zeolite (OZ), nano zeolite (NZ) was better in increasing the biomass of Chinese cabbage as well as decreasing accumulation of Cd in Chinese cabbage.
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Brassica/metabolismo , Cádmio/metabolismo , Nanopartículas , Poluentes do Solo/metabolismo , Zeolitas , Concentração de Íons de Hidrogênio , SoloRESUMO
OBJECTIVE: To study the changes of nutrient contents in Chinese goldthread soil before and after planting Coptis chinensis. METHOD: The soil in Shizhu, Chongqing, was analyzed for nutrient contents. RESULT AND CONCLUSION: The results indicated that the preplanted soil was strongly acidic and the levels of organic matter, total nitrogen and potassium were high. However, the content of total phosphorus was very low; so were the contents of other eleven nutrients. Variations of nutrients except zinc and molybdenum were large. After four years of planting C. chinensis, the soil pH was increased. Contents of organic matters, manganese, zinc and boron were increased, while the contents of iron and copper were decreased. In general, the variance coefficient of all nutrient elements and the difference of soil fertility were decreased.
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Coptis/crescimento & desenvolvimento , Fertilizantes , Plantas Medicinais/crescimento & desenvolvimento , Solo/análise , China , Ecossistema , Concentração de Íons de Hidrogênio , Ferro/análise , Manganês/análise , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Zinco/análiseRESUMO
As a new style fertilizer, slow-control release fertilizer had been an important subject in recent years, but few researches were about soil microbial community structure diversity. Phospholipid fatty acid method was used to determined the microbial community structure diversity of acid soil and slight alkaline soil applied with slow-release compound fertilizer (SRF), chemical fertilizer (CF) and common compound fertilizer (CCF) at the 10th, 30th, 60th and 90th day under the constant temperature incubation condition. Results indicated that various bacteria (i. e 13:0, i14:0,14:0, i15:0, a15:0, i16:0, 16:12OH, 16:1w5c,16:0, i17:0, a17:0, cy17:0, 17:02OH, i18:0, 18:0 and cy19:0w8c), two actinomycetes (10Me17:0 and 10Me18:0) and only one fungus (18:1 w9c) were detected in two soils after applying slow-release compound fertilizer and other fertilizers during the whole incubation period. SRF could significantly increase the fungi PLFA content by 8.3% and 6.8% at the early stage (the 10th day and 30th day) compared with CF, as well as significantly increase by 22.7% and 17.1% at the late stage (the 60th day and 90th day) compared with CCF in acid soil. SRF significantly increased bacteria, fungi and gram positive bacteria compared with CF and CCF in incubation period (except at the 30th day) in slight alkaline soil. SRF could significantly improve the ratio of normal saturated fatty acid and monounsaturated fatty acid at the 30th day and 90th days in acid soil compared with no fertilizer (CK), CF and CCF, while as to slight alkaline soil, SRF was significantly greater than that of CK, CF and CCF only at the 60th day. SRF could significantly decrease the ratio of iso PLFA and anteiso PLFA in acid soil (in 30-90 days) and slight alkaline soil (in 10-60 days). For two soils PLFA varieties, contents and ratios of microbial community, slow-release compound fertilizer increased soil microbial PLFA varieties and contents, and decreased the influence to microbial survival environment, especially for the acid soil. Through the research of slow-release compound fertilizer on soil microbial community structure diversity, it could provide a scientific basis for widely application of slow-release compound fertilizer in agricultural production.
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Fertilizantes , Microbiologia do Solo , Solo/química , Agricultura , Bactérias , Ácidos Graxos , Fungos , Compostos Inorgânicos , FosfolipídeosRESUMO
Pot experiments were carried out to investigate the influence of different selenium (Se) levels (0, 0.5 and 1.0 mg x L(-1)) on the plant growth, concentration of malonaldehyde (MDA), activities of antioxidant enzymes, accumulation and chemical forms of cadmium (Cd) in cucumber when exposed to Cd (20 mg x kg(-1)). The results showed that dry weights of leaf, stem, root, fruit and plant, and concentrations and accumulation of Cd significantly differed between two varieties of cucumber Yanbai and Jinyou 1. With increasing levels of Se, the contents of MDA in the leaves of Yanbai increased, but the contents of MDA in the leaves of Jinyou 1 decreased. The contents of MDA in the roots of Yanbai first increased and then decreased, while the contents of MDA in Jinyou 1 first decreased and then increased. The variation trends of CAT, SOD and POD in the leaves and roots of both varieties were different with increasing levels of Se. The concentrations of different chemical forms of Cd in the fruit decreased after spraying of Se, compared with the control. Cadmium concentrations in the leaves, stem, roots and fruit of both varieties decreased by 3.2%-17.9%, 14.6%-28.2%, 5.1%-18.5% and 60.6%-75.8% in the presence of Se when exposed to Cd. Accumulation of Cd in the plant of both varieties was in order of Jinyou 1 > Yanbai in the presence or absence of Na2SeO3.
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Cádmio/química , Cucumis sativus/química , Selênio/química , Antioxidantes/análise , Frutas , Malondialdeído/análise , Folhas de Planta , Raízes de Plantas , Caules de PlantaRESUMO
Incubation experiments were carried out to investigate the influence of different nano zeolite (NZ) and ordinary zeolite (OZ) levels(0, 5, 10 and 20 g · kg⻹) on the change trends in fraction distribution coefficient (FDC) of Cd when exposed to different Cadmium (Cd) levels (1, 5, 10 and 15 mg · kg⻹), and pot experiments were carried out to investigate their influence on soil Cd fraction and Cd uptake by cabbage. The results in incubation experiments showed that the application of nano zeolite as well as ordinary zeolite effectively decreased the FDC of exchangeable Cd and increased the FDC of Fe-Mn oxide fraction. The FDC of soil Cd from 0 d to 28 d was deceased at first, then increased and tended to be stable, and finally increased. At the end of incubation, the FDC of soil exchangeable Cd decreased from 72.0%-88.0% to 30.0%-66.4%. Exchangeable fraction Cd was the most dominant Cd fraction in soil during the whole incubation. The results in pot experiment indicated that the application of nano zeolite and ordinary zeolite decreased the concentration and FDC of soil exchangeable Cd, and concurrently the concentration and FDC of Cd in carbonate, Fe-Mn oxide, organic matter and residual fraction were increased. The lowest EX-Cd was observed in the treatment with high dose of nano zeolite (20 g · kg⻹). The FDC of exchangeable Cd showed significant negative relationship with the soil pH (P < 0.05), and was concurrently extremely positively correlated with Cd concentration in shoot and root of cabbage (P < 0.01). Soil pH increased by 1.8%-45.5% and 6.1%-54.3% in the presence of zeolite when exposed to 5 mg · kg⻹ 1 and Cd, respectively; FDC of exchangeable Cd decreased by 16.3%-47.7% and 16.2%-46.7%; Cd concentration in each tissues of cabbage decreased by 1.0%-75.0% and 3.8%-53.2%, respectively. Moreover, the reduction effect of nano zeolite on soil and plant Cd was better than that of ordinary zeolite. The growth of cabbage was stimulated by low and medium zeolite doses (≤ 10 g · kg⻹), while inhibited by high zeolite doses (20 g · kg⻹). Compared to ordinary zeolite, the biomass of Chinese cabbage was significantly increased by Nano zeolite, while the exchangeable Cd in soil as well as Cd concentration and Cd accumulation of cabbage were significantly reduced.
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Brassica/metabolismo , Cádmio/química , Nanopartículas/química , Poluentes do Solo/química , Zeolitas/química , Raízes de Plantas , SoloRESUMO
Pot experiments were carried out to investigate the effects of ryegrass and arbuscular mycorrhiza on the plant growth, malondialdehyde (MDA), antioxidant enzyme activities of leaf and root, accumulation and chemical forms of cadmium (Cd) in tow varieties of tomato when exposed to Cd (20 mg x kg(-1)). The results showed that dry weights of fruit and plant, and contents of malondialdehyde (MDA) and antioxidant enzyme activities of leaf and root, and concentrations and accumulations of Cd significantly differed between two varieties of tomato. Dry weights of fruit, roots, stem, leaf and plant were increased by single or combined remediation of ryegrass and arbuscular mycorrhiza, while MDA contents and antioxidant enzyme activities of leaf and root reduced. The total extractable Cd, F(E), F(W), F(NaCl), F(HAc), F(HCl), and F(R) in fruit of two varieties of tomato reduced by 19.4% - 52.4%, 31.0% - 75.2%, 19.7% - 59.1%, 3.1% - 48.2%, 20.0% - 65.0%, 40.7% - 100.0% and 15.2% - 50.0%, respectively. Cadmium accumulations in tomato were in the order of leaf > stem > fruit > root. Cadmium concentrations in leaf, stem, root and fruit of both varieties decreased by single or combined remediation of ryegrass and arbuscular mycorrhiza, and Cd accumulations of stem and plant of two varieties also reduced. Cd accumulations in fruit of two varieties decreased by 42.9% and 43.7% in the combined remediation treatments, respectively. Tolerance and resistance of 'LUO BEI QI' on Cd was more than 'De Fu mm-8', and Cd concentrations and Cd accumulations in fruit and plant were in the order of 'LUO BEI QI' < 'De Fu mm-8' in the presence or absence of single or combined remediation of ryegrass and arbuscular mycorrhiza.
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Cádmio/química , Lolium , Micorrizas , Solanum lycopersicum/enzimologia , Solanum lycopersicum/microbiologia , Antioxidantes/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Malondialdeído/química , Folhas de Planta/enzimologia , Raízes de Plantas/enzimologiaRESUMO
By combining field investigation and indoor chemical analysis, the relationship between tumorous stem mustard yield and soil fertility factors was investigated in the main planting areas of tumorous stem mustard in Fuling, Southwest China. The results showed that available Ca, Mg, Fe, Mn, Cu and Zn in the soil were rich (3034, 260, 11.2, 26.1, 1.15 and 1.50 mg x kg(-1), respectively), available P was moderate (19.3 mg x kg(-1)), and organic matter, available N, available K and available S were deficient (9.05 g x kg(-1), 89.2 mg x kg(-1), 106 mg x kg(-1) and 27.0 mg x kg(-1), respectively). The yield of tumorous stem mustard was significantly positively correlated with soil pH and available Ca, whilst significantly (P < 0.01) negatively correlated with available Fe. The influence order of soil fertility factors on the yield of tumorous stem mustard was available Mn > available Cu > pH > available Fe > available K > available Ca > available Mg > available S > available N > available Zn > organic matter > available P. The linear equation (Y = 31636 + 3.63X(6)) of soil available Ca and the yield, was established by stepwise regression analysis.
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Mostardeira/crescimento & desenvolvimento , Solo/química , ChinaRESUMO
By using venting method incubation experiment, we studied the ammonia volatilization and kinetics characteristics of uncoated slowed release compound fertilizer (SRF) under different soil water conditions and the growth and nitrogen utilization efficiency of rice in pot experiment. Results indicated that the ammonia volatilization of SRF under waterflooding reached the peak ahead of 3-4 days compared to the moist treatment. The peak and accumulation of ammonia volatilization in the waterflooding treatments were higher than those under the moist condition. SRF could significantly reduce total ammonia volatilization compared to the common compound fertilizer (CCF), reduced by 50.6% and 22.8% in the moist treatment and reduced by 24.2% and 10.4% in the waterflooding treatment,but the loss of ammonia volatilization of SRF was higher significantly than that of the coated fertilizer (CRF). Ammonia volatilization increased with the increasing of fertilizer application. The dynamics of ammonia volatilization of SRF could be quantitatively described with three equations: the first order kinetics equation, Elovich equation and parabola equation. Compared to moist condition, the biomass of rice plant in SRF, CCF and SRF treatments increased by 67.86%, 78.25% and 48.75%, and nitrogen utilization efficiency increased by 57.73%, 80.70% and 12.06% under waterflooding condition, respectively. Comparing with CCF, nitrogen utilization efficiency in SRF treatment improved by 59.10% and 10.40% under two soil moisture conditions. SRF could reduce ammonia volatilization and improve biomass and nitrogen utilization efficiency.
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Amônia/análise , Fertilizantes , Nitrogênio/análise , Solo/análise , Água/análise , Agricultura/métodos , Amônia/química , Oryza/crescimento & desenvolvimento , VolatilizaçãoRESUMO
Nitrate accumulation in vegetables, which related well to vegetable nutrition, becomes one of the limiting factors of non-pollution vegetables production. Preference to nitrate is the nutritional characteristic of vegetables. Nitrate is absorbed by vegetables through high-affinity transport system (HATS) and low-affinity transport system (LATS), and is reduced and transformed under the effect of such essential elements as molybdenum, manganese, iron, copper, sulphur and phosphorus. In this paper, the effects of essential elements on nitrate absorption and reductive transform were reviewed, and the relationships of nitrate accumulation in vegetables with vegetable nutrition of nitrogen, phosphorus, potassium and mid-and microelements as well as with balanced fertilization were discussed. The research keys in the field were prospected for controlling nitrate accumulation, improving vegetables' quality and producing non-pollution vegetables.