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Although the planktonic eukaryotic community (PEC) is an important component of freshwater ecosystems and plays an important ecological role, the impact of artificial water ecological modification on PEC has not been fully evaluated. To analyze the impact of lotus planting on the structure of PEC in urban park ponds, in this study, we analyzed the differences in PECs in different regions (artificial fountain region, potted lotus region, and direct lotus planting region) of an urban pond in subtropical China before and after lotus planting in the short term (~10 d) and for more than a month. Our results indicated that more than a month after planting lotuses, there were evident differences in the compositions of PECs in the three regions. Although there was no significant difference in operational taxonomic unit number and Chao1 indices before and after planting lotuses, planting lotuses significantly increased the Shannon index of the PECs. Moreover, different planting modes of lotuses can alter the structure of PECs after more than a month of growth, and planting lotuses can continuously strengthen the interconnection of various organisms in the PECs. These results expand our understanding of the impacts of artificial ecological modifications on the structure of PECs in urban ponds. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions are attracting considerable interest in scientific research and practical applications. Recently, a novel phenomenon was observed in which a skyrmion bubble lattice could be induced by a slightly tilted in-plane magnetic field in a multilayer film. In this article, the formation process of a skyrmion bubble lattice was investigated by micromagnetic simulation considering the Dzyaloshinskii–Moriya (DM) interaction and distribution of magnetic anisotropy. The exchange field that prevents the reversal of moments was minimized when the magnetic moments were aligned by a slightly tilted in-plane magnetic field. Many small reversed domains were formed in the regions where the demagnetization field conquers the anisotropy field after the removal of the external field and developed into a stable skyrmion bubble array. The DM interaction has an obvious influence on the size and precise moment structure of the stable skyrmion bubbles but has little effect on the nucleation of reversed domains. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES: Epidemiological evidence is suggestive, but inconclusive, for an association between consumption of red and processed meat and risk of stroke. We aimed to assess this association by conducting a meta-analysis of prospective cohort studies. SUBJECTS/METHODS: We performed a literature search on PubMed database through June 2012 to indentify prospective cohort studies of red and processed meat intake in relation to risk of stroke. Reference lists of the retrieved articles were also reviewed. Both fixed-effects and random-effects model were assumed to compute the summary risk estimates. RESULTS: Five large independent prospective cohort studies were identified. These studies contained a total of 2 39 251 subjects and 9593 stroke events. Comparing the highest category of consumption with lowest category, the pooled relative risks (RRs) of total stroke were 1.15 (95% confidence interval (CI), 1.05-1.25) for total meat (red and processed meat combined) (n = 4), 1.09 (95% CI, 1.01-1.18) for red meat (n = 5) and 1.14 (95% CI, 1.05-1.25) for processed meat (n = 5); the corresponding RRs of ischemic stroke (highest vs lowest quintile) were 1.15 (95% CI, 1.04-1.28), 1.13(95% CI, 1.01-1.25) and 1.19 (95% CI, 1.08-1.31). Consumption of red and/or processed meat was not associated with hemorrhagic stroke. In the dose-response analysis, the risk of stroke increased significantly by 10% and 13% for each 100g per day increment in total and red meat consumption, respectively, and by 11% for each 50g per day increment in processed meat consumption. CONCLUSION: Findings from this meta-analysis indicate that consumption of red and/or processed meat increase risk of stroke, in particular, ischemic stroke. European Journal of Clinical Nutrition (2013) 67, 91-95; doi: 10.1038/ejcn.2012.180; published online 21 November 2012 Keywords: meat; stroke; prospective studies; meta-analysis, INTRODUCTION In most developed countries, stroke remains an important cause of mortality and the most common cause of disability, and is becoming a great health burden in future decades. (1) [...]

BACKGROUND/OBJECTIVES: Epidemiological studies have suggested that dietary fiber intake may be associated with a decreased risk of stroke, but the findings have been inconsistent. We aimed to assess this association by conducting a meta- analysis of prospective cohort studies. SUBJECTS/METHODS: We performed a literature search on PubMed database through July 2012 to indentify prospective studies of dietary fiber intake in relation to risk of stroke. We also comprehensively reviewed the reference lists of the retrieved articles to identify additional studies. We used a random-effects model to compute the summary risk estimates. RESULTS: Six prospective cohort studies containing a total of 314864 subjects and 8920 stroke cases were included. The summary relative risk (RR) of stroke for the highest vs lowest category of dietary fiber intake was 0.87 (95% confidence interval (CI), 0.77-0.99). The corresponding RR in the subgroup analyses for men and women was 0.95 (95% CI, 0.83-1.08) and 0.80 (95% CI, 0.66- 0.96), respectively; and for ischemic stroke and hemorrhagic stroke was 0.83(95% CI, 0.72-0.96) and 0.86 (95% CI, 0.70-1.06), respectively. Meta-regression indicated no significant difference between gender (P-interaction = 0.18), or stroke subtypes (P- interaction = 0.85). The dose-response analysis suggested a 12% (RR = 0.88;95% CI, 0.79-0.97) reduction in risk of stroke for each 10g per day increment in dietary fiber intake. Moderate heterogeneity emerged in some of analyses, but disappeared after removing one study substantially contributing to the heterogeneity. Little evidence of publication bias was detected. CONCLUSION: Findings of this meta-analysis indicate a significant inverse dose-response relationship between dietary fiber intake and risk of stroke. European Journal of Clinical Nutrition (2013) 67, 96-100; doi: 10.1038/ejcn.2012.158; published online 17 October 2012 Keywords: prospective studies; stroke; dietary fiber; meta-analysis, INTRODUCTION In most developed countries, stroke remains an important cause of mortality and the most common cause of disability, and is becoming a great health burden in future decades. (1) [...]

Zooplanktons play an important role in the whole freshwater ecosystem, which are the main quality food for almost all fish in their juvenile stage and are the main basic component of the high trophic levels in the aquatic food web. In the context of global environmental change, freshwater zooplankton is experiencing rapid loss of biodiversity and ecosystem integrity. However, our understanding of the geographical distribution pattern of freshwater zooplankton and the diversity-affected ecological factors is still very limited. In order to investigate the research status and future development trend of zooplankton in global freshwater, 26176 publications about freshwater zooplankton/zooplankter indexed by Web of Science from 1991 to 2020 were analyzed with a bibliometric approach in our study. The research contents mainly included the output trend of publications related to the freshwater zooplankton/zooplankter filed over time, the journals with greatest number of zooplankton publications, the countries from which the authors came from, the co-authors and cooperation across countries, the associated keywords in the research areas and so on. This study was searched on a scientific website for scientific study that have limited scientific relevance for the future researches on the freshwater zooplankton. [ABSTRACT FROM AUTHOR]

To explore the spatial and temporal distribution characteristics of phytoplankton functional groups (PFGs) of the Dongta spawning grounds in the Pearl River, China, quarterly surveys of this area were carried out during March, 2016 to December, 2018, and the ecological status was analyzed and evaluated according to PFGs assemblage index (Q index). 26 PFGs were identified, and the dominant PFGs were C, D, J, K, L0, MP, N, P, S1, S2, T, W1, W2, X2, Y in this area. Phytoplankton Q indexes varied from 1.83 to 3.73, with the mean value 2.91, which showed that the ecological status of the Dongta spawning grounds was “medium” and “good”, but parts occasionally were “tolerable”. Temporally, the general ecological status was good in March and June, but it was medium in September and December. Basing on our study, the results showed that: (1) factors including water velocity (V), DO, Chla, phosphate, oxidation reduction potential, total phosphorus, electrical conductivity, total dissolved solid and salinity were significantly correlated with the dominant PFGs; (2) the phytoplankton Q index was significantly correlated with the V. It was suggested that after the construction and operation of Datengxia Water Dam and its upper reaches cascade dams, attention should be paid to regulate the water flow and velocity in the lower reaches of the river by means of ecological operation, so as to ensure the functions of the spawning grounds and protect the fishery conservation zones in the mainstream of the Pearl River. [ABSTRACT FROM AUTHOR]

There is often intense competition among species in an environment with limited resources and space, leading to the exclusion of inferior competitors, reduced species diversity, and changes in zooplankton communities. This study investigated the interspecific competition between two dominant rotifer species in the Pearl River Basin, Brachionus calyciflorus and Keratella valga, through laboratory experiments at different temperatures, food concentrations, and initial rotifer densities. In separate cultures, the population growth of both rotifer species was affected by changes in temperature, food density, and initial density. In mixed cultures, B. calyciflorus was inhibited by competition, leading to an overall decrease in its population growth rate and maximum population density. K. valga was also affected by competition, leading to an increase in its population growth rate and maximum population density at 20 ℃ or at an initial density of 1.0 × 106 cells/mL. B. calyciflorus was excluded by K. valga at low and medium food concentrations (0.5 × 106 and 1.0 × 106 cells/mL), whereas the opposite was found at high food concentration (3.0 × 106 cells/mL). Food concentration is obviously the main factor affecting outcome. Temperature, initial density, and interactions between the three factors also have an effect on it. [ABSTRACT FROM AUTHOR]

In our study, zeolite, sepiolite, vermiculite and biochar were added to high-concentration lead-contaminated soils, respectively, and the metal fractions, toxicity leaching amount and leaching characteristics of lead (Pb) in soils were studied after 30 d. Besides, the feasibility of chemical immobilization to reduce Pb was investigated. In the soil immobilization experiments, compared with the control, the toxicity leaching amount of soils added zeolite, sepiolite, vermiculite and biochar decreased. The decreasing ratios were 40.12%, 41.28%, 25.50%, and 16.04%, respectively. It is clear that the treatment of zeolite showed the best effect. And the group matching curing agents (GMCAs) with a mass ratio of 2:1 for zeolite and sepiolite was the best, of which the Pb content in soil leaching solutions decreased by 41.4%. Meanwhile, through soil column leaching experiment, compared with the control, the pH of leachates generally increased, and the electrical conductivity (EC) of leachates presented a falling trend. The Pb content of accumulated leachates from treatments decreased, and the best effect treatment was at a mass ratio of 1:2 for zeolite andsepiolite with the highest decrease rate at 93.35%. And the immobilization effect was further verified. Therefore, the addition of curing agents could decrease the bioavailability and migration of Pb. [ABSTRACT FROM AUTHOR]

Abstract: Trimeric surfactant modified montmorillonite immobilized in alginate beads (CA/3RenQ-Mt) sorbent was synthesized to simultaneously remove Cu2+ and methyl orange (MO) from aqueous solution. The CA/3RenQ-Mt was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TG), zeta potential analysis and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) analysis. The adsorption of Cu2+ and MO by CA/3RenQ-Mt was studied by the operational variables including contact time, pH and temperature. The results showed CA/3RenQ-Mt exhibited higher affinity to both Cu2+ and MO compared to sodium montmorillonite (Mt-Na), trimeric surfactant modified montmorillonite (3RenQ-Mt) or calcium alginate (CA). The pseudo-first-order kinetic model and Langmuir isotherm model were found to describe the MO adsorption well; the pseudo-second-order kinetic model and Freundlich isotherm model fitted well with the Cu2+ adsorption. The adsorption of MO onto CA/3RenQ-Mt is an endothermic spontaneous process, and ion-exchange was the dominant adsorption mechanism. Accordingly, the adsorption of Cu2+ on CA/3RenQ-Mt involved endothermic spontaneous chemical adsorption by means of coordination/chelation between Cu2+ and the oxygen atoms of carboxyl and hydroxyl groups of alginate. In general, CA/3RenQ-Mt can be applied as multifunctional adsorbent to remove heavy ions and anion dyes from aqueous solution. [ABSTRACT FROM AUTHOR]

By micromagnetic simulation, we investigated a double 360° domain walls system in two parallel nanowires. Two domain walls are coupled to each other via magnetostatic interaction. When a spin-polarized current is applied to only one nanowire or both nanowires with the same direction, the two domain walls propagate along nanowires together. The critical velocity of such system is obviously higher than that of a single 360° domain wall. The interaction between the two domain walls can be modeled as two bodies that connected by a spring, and we analyzed the coupling characteritics of the double 360° domain walls at last. [ABSTRACT FROM AUTHOR]

In this study, a double exponential model is proposed to investigate the cylindrical crack problem for a functionally graded superconducting cylinder. The stress intensity factors (SIFs) are analytically obtained by transforming the corresponding crack problem into dual integral equations. The effects of applied magnetic field, model parameters, and crack configuration on the SIFs are analyzed. Some important phenomena are observed. Among others, both decreasing the graded index of Young's modulus and increasing the introduced nondimensional exponent parameter in the critical current model can inhibit crack propagation. This study should be useful for the application of superconducting devices. [ABSTRACT FROM AUTHOR]