Tree-herb intercropping was proposed for use in remediation of metal(loid)-contaminated soil. Changes in the enzymatic activities and microbial communities in contaminated soil during tree-herb ...intercropping were studied through dynamic sampling in a greenhouse experiment. Two herb plants, Pteris vittata L. (W) and Arundo donax L. (L), and two tree plants, Morus alba L. (S) and Broussonetia papyrifera L. (G), were selected for tree-herb intercropping, namely SL, GL, GW, SW, and GSLW intercropping. The activities of four enzymes, dehydrogenase activity (DHA), urease activity (UA), sucrase activity (SA) and acid phosphatase activity (APA), are involved in N, C, P cycling and were measured colorimetrically, while the bacterial and arbuscular mycorrhizal (AM) fungal community structures were determined using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that tree-herb intercropping could effectively recover enzymatic activity, and bacterial and AM fungal diversity in metal(loid)-contaminated soil. Compared with treatment without plants, the SA and APA activity after the five tree-herb intercropping treatments were significantly (p < 0.05) increased by 1.64–2.51 times and 2.35–5.70 times after 270 d of cultivation, respectively. Meanwhile, the Shannon-Wiener indexes for bacteria and AM fungi increased by 13.6–17.7% and 20.0–36.9%, respectively. Soil DHA, UA, and SA were slightly affected by tree-herb intercropping; however, APA was further significantly enhanced by SL, GL, and GSLW intercropping when compared to the monoculture treatments after 270 d of cultivation. These results indicated that tree-herb intercropping could effectively mitigate the toxic effects of metal(loid)s on soil enzyme activities and microbial community structures and enhance the potential for ecological remediation of metal(loid)-contaminated soil in mining areas.
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•Tree-herb intercropping improves the biological quality of polluted soil.•Soil enzyme activity and microbial diversity benefited from tree-herb intercropping.•Acid phosphatase activity was further enhanced by SL, GL, and GSLW intercropping.•Tree-herb intercropping had a significant impact on the AM fungal community in soil.
Knowledge on adsorption behaviour of vanadium (V) on natural clay minerals is critical to understand V mobility in soil and aqueous systems. In this study, the characteristics and mechanisms of V(V) ...adsorption on two abundant soil clay minerals, namely, natural kaolinite and montmorillonite, as well as the effects of solution pH and ionic strength on the adsorption process were investigated. The results showed that the kinetics of V(V) adsorption on kaolinite and montmorillonite conformed to pseudo second-order, and reached equilibrium within 240 min and 360 min respectively. The adsorption isotherms of V(V) on kaolinite were better fit with the Freundlich model, while the Langmuir model was a better fit for montmorillonite. The Langmuir model indicated that natural montmorillonite and kaolinite have low affinity for V(V) anions with maximum adsorption capacity of 0.98 mg·g−1 and 0.78 mg·g−1, respectively. The higher capacity was found at pH 4–10 due to the mass formation of deprotonated hydroxyl groups for V adsorption. The V adsorption capacity on montmorillonite increased with the increasing ionic strength of NaNO3. The results of pH and ionic-strength effect showed that surface complexation and electrostatic interaction may be the V(V) adsorption mechanisms.
•Pseudo second-order, Freundlich and Langmuir model described vanadium (V) adsorption to natural kaolinite and montmorillonite.•V(V) adsorption was pH dependent with higher capacity in pH range of 4–10.•Surface complexation and electrostatic interaction (Na+-bridge) may be the V(V) adsorption mechanisms.
Woody plants have considerable application potential in the phytoremediation schemes, owing to their long-lived large biomass and prosperous root systems in heavy metal(loid)–contaminated soil. Under ...greenhouse conditions, the physiological response characteristics and phytoremediation possibility of
Morus alba
L. and its associated improvement of the bacterial and arbuscular mycorrhizal fungal (AMF) diversities in heavy metal(loid) co-contaminated soils were investigated. The results showed that the cultivated
M
.
alba
L. plant exhibited significant tolerance against the heavy metal(loid)s in co-contaminated soil and that the microbial diversities were improved notably. The contents of malondialdehyde (MDA) in
M
.
alba
L. leaves decreased with cultivation from 90 to 270 days, while the superoxide dismutase, peroxidase and catalase activities were maintained at normal levels to eliminate the production of lipid peroxides. The chemical compositions (e.g. amino acids, carbohydrates and proteins) in the root of
M
.
alba
L. fluctuated slightly throughout the cultivation period. Meanwhile, Cd, Pb and Zn were majorly concentrated in the
M
.
alba
L. roots, and the maximum contents were 23.4, 7.40 and 615.5 mg/kg, respectively. According to the polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) analysis results, the influence of
M. alba
L. on the rhizosphere AMF community was greater than that on the bacteria community. Meanwhile, the bacterial and AMF Shannon diversity indexes in the contaminated soil were enhanced by 18.7–22.0% and 7.14–16.4%, respectively, with the presence of
M. alba
L. Furthermore, the correlations between the availability of As, Cd, Pb, and Zn and Shannon diversity indexes of the bacterial and AMF communities were significantly (
p
< 0.05) positive with the phytoremediation of
M
.
alba
L. Therefore,
M
.
alba
L. can be suggested as a potential plant candidate for ecological remediation and for simultaneously improving the activity and diversity of microorganisms in contaminated soils.
The Industrial Internet of Things (IIoT) is the essential component of Industry 4.0. Blockchain is a promising technology for secure data sharing and trustable cooperation between IIoT devices. ...However, the ever-growing transaction records make it difficult for the storage-limited IIoT devices to join the blockchain network. In this article, an adaptive compression scheme is proposed to decrease the storage volume on each node. In the scheme, the block body is compressed by representing the included transactions as their remainders stored in the distributed nodes. The original transaction could be recovered based on the Chinese remainder theorem. In particular, each node adapts its compression ratio according to its storage resource. The nodes storing more data have advantages in transaction recovery, introducing an incentive mechanism for efficient storage utilization. The theoretical analysis and simulation results show that the proposed scheme can achieve a high compression ratio with good service availability. The proposed scheme dramatically lowers the threshold for IIoT devices to join the blockchain network, which is important for the large-scale application of blockchain in Industry 4.0.
Variations in immune cell counts can trigger depressive symptoms, while physical activity effectively reduces the risk and severity of depressive symptoms. This study, based on the NHANES database, ...analyzes the relationship between neutrophil count and depressive symptoms and explores the moderating effect of physical activity on this relationship. Cross-sectional data from the NHANES database were extracted, including immune cell counts, PHQ-9 scores for self-assessment of depressive symptoms, and Global Physical Activity Questionnaire (GPAQ) scores (PA). The interrelations among physical activity, neutrophil count, and depressive symptoms were analyzed. After controlling for confounding factors, neutrophil count was found to have a significant role in identifying depressive symptoms with an odds ratio (OR) 95% Confidence Interval (CI) = 1.13 1.02, 1.251; the moderating effect of physical activity on the impact of neutrophil count on depressive symptoms was statistically significant (coefficient = -0.0028, P < 0.05). Neutrophil count may be a significant factor in identifying depressive symptoms in adults. As an effective moderating factor, physical activity can mitigate the impact of neutrophil count on depressive symptoms to a certain extent.
Exploiting soil microorganisms in the rhizosphere of plants can significantly improve agricultural productivity; however, the mechanism by which microorganisms specifically affect agricultural ...productivity is poorly understood. To clarify this uncertainly, the rhizospheric microbial communities of super rice plants at various growth stages were analysed using 16S rRNA high-throughput gene sequencing; microbial communities were then related to soil properties and rice productivity.
The rhizospheric bacterial communities were characterized by the phyla Proteobacteria, Acidobacteria, Chloroflexi, and Verrucomicrobia during all stages of rice growth. Rice production differed by approximately 30% between high- and low-yield sites that had uniform fertilization regimes and climatic conditions, suggesting the key role of microbial communities. Mantel tests showed a strong correlation between soil conditions and rhizospheric bacterial communities, and microorganisms had different effects on crop yield. Among the four growing periods, the rhizospheric bacterial communities present during the heading stage showed a more significant correlation (p < 0.05) with crop yield, suggesting their potential in regulating crop production. The biological properties (i.e., microbes) reflected the situation of agricultural land better than the physicochemical characterics (i.e., nutrient elements), which provides theoretical support for agronomic production. Molecular ecological network (MEN) analysis suggested that differences in productivity were caused by the interaction between the soil characteristics and the bacterial communities.
During the heading stage of rice cropping, the rhizospheric microbial community is vital for the resulting rice yield. According to network analysis, the cooperative relationship (i.e., positive interaction) between between microbes may contribute significantly to yield, and the biological properties (i.e., microbes) better reflected the real conditions of agricultural land than did the physicochemical characteristics (i.e., nutrient elements).
The changes of available forms of heavy metals would affect their corresponding ecological risks in sediments. The distribution of chemical fractions of heavy metals in sediment profiles from ...Chunfeng Lake estuary was investigated and then a prediction model for potential ecological risk index (PMRI) was proposed to forecast the changes of ecological risks caused by the aging process of metals in sediments. The results show that the estuarine sediments were polluted by As and Cd. The proportions of available metals were generally decreased with depth, while those of the residual forms showed an opposite trend. The aging rates of Cd and As were found to be 0.21 and 0.12%/year, respectively. The PMRI model showed that the total ecological risk of metals in sediments decreased from moderate to low risk level (<150) after 25 years, while cadmium would need 47 years in contrast to the 15 years for As.
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•Distributions and chemical fractions of metals in the sediment profiles were studied.•The available metals were changing to unavailable forms with increasing depth.•The aging rates of Cd and As in the sediment profiles were 0.21 and 0.12%/year.•A model is proposed to predict ecological risk of metals in the sediment profiles.•The ecological risk of metals decreased from moderate to low level after 25 years.
Long noncoding RNAs (lncRNAs) have been verified as vital regulators in human disease, including atherosclerosis. However, the precise role of X-inactive-specific transcript (XIST) in atherosclerosis ...remains unclear. The proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) exposed to low-density lipoprotein (ox-LDL) were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2
-tetrazol-3-ium bromide, and flow cytometry assays, correspondingly. The western blot assay was used to quantify protein expression. Lactate dehydrogenase activity and the concentrations of inflammatory factors were measured by matched kits. The real-time quantitative polymerase chain reaction (qPCR) was used to determine α-smooth muscle actin, smooth muscle protein 22-α, XIST, miR-98-5p, and pregnancy-associated plasma protein A (PAPPA) levels in HUVECs. The relationship among XIST, miR-98-5p, and PAPPA was analyzed by dual-luciferase reporter, RNA immunoprecipitation, and RNA pull-down assays. We found ox-LDL repressed proliferation and induced inflammation and apoptosis in HUVECs. Loss-of-functional experiment suggested that the downregulation of XIST overturned the ox-LDL-induced effects on HUVECs. Additionally, overexpression of miR-98-5p-induced effects on ox-LDL-stimulated HUVECs was abolished by upregulation of XIST. However, silencing of miR-98-5p strengthened the ox-LDL-induced effects on HUVECs by increasing expression of PAPPA. Mechanistically, XIST could regulate PAPPA expression in ox-LDL-induced HUVECs by sponging miR-98-5p, providing understanding for atherosclerosis.
To explore the association between depression and anxiety symptoms among college students and the relationship between the two and physical activity. A cross-sectional study design was used to survey ...1790 enrolled university students using the Depression Self-Rating Scale, Anxiety Self-Rating Scale and Physical Activity Rating Scale. 37.75% of male students and 39.73% of female students detected depressive symptoms, 17.65% of male students and 17.86% of female students detected anxiety symptoms, 11.89% of male students and 11.75% of female students detected both depressive and anxiety symptoms. Canonical correlation between depression and anxiety symptoms of college students were significant. The depression and anxiety score of college students in the high level group was significantly lower than that in the low and medium level groups, and no significant difference was found between the low and medium level groups. Affective disorder and anxious mood of male students correlated most closely with intensity, while somatic disorder, psychomotor disorder and depressive psychological disorder correlated most closely with duration. Affective disorder of female students correlated most closely with frequency, depressive psychological disorder and anxious mood correlated most closely with intensity, while premonition of misfortune and frequent urination correlated most closely with duration. Depression and anxiety symptoms of college students were closely related and co-occurrence was common. Students with high level of physical activity had milder symptoms. Different exercise interventions are recommended for different symptoms.
Ferromanganese oxides, as abundant minerals in natural waters and soils, would affect the transport and fate of vanadium(V) in the environment. The adsorption behaviour of V(V) on synthesized ...goethite and birnessite under environmental factors including pH, ionic strength, coexisting substances such as anions, cations, and fulvic acid (FA) was investigated by batch experiments. The results indicated that the kinetics model of V(V) adsorption on goethite and birnessite well fitted with pseudo-second-order, and the adsorption equilibrium was achieved in 60 min and 120 min, respectively. The V(V) adsorption isotherms for goethite and birnessite conformed to the Langmuir isotherm with maximum adsorption amount of 8.24 and 9.11 mg·g
–1
, respectively. The higher V(V) adsorption capacity on goethite was observed at pH 4–8, while that on birnessite occurred at pH 2 owing to their different point of zero charge pH. The V(V) adsorption amounts of the synthesised materials were decreased with the increase in ionic strength of NaNO
3
but increased with the elevating FA concentration in solution. The inhibitory effect on V(V) adsorption was found in the presence of anions of PO
4
3−
and SO
4
2−
, while cations like Ca
2+
and Mg
2+
facilitated the adsorption. The obtained results are of great importance to understand V(V) mobility in soil and aqueous environment.
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