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The catalytic materials for sulfate radical-based advanced oxidation processes with the performance of high activity and stable had attracted significant attention in the field of sustainable wastewater treatment. Here, a novel adsorption-reactive composite catalyst with Fe3O4 impregnated acrylamide-based hydrogel (PAM-AMPS/Fe3O4) was designed and synthesized for methylene blue (MB) degradation based on persulfate advanced oxidation processes. For the acrylamide-based hydrogel, the monomer of 2-acrylamide-2-methyl-propanesulfonic acid (AMPS) was added to improve the adsorption performance of the composite, and the maximum adsorption capacity of the selected hydrogel was about 40 mg/g. In the presence of the persulfate activated system, the degradation efficiency of MB of PAM-AMPS/Fe3O4 was significantly increased to a level of 94% in 20 min. This value was far superior to catalytic systems without the AMPS. This outstanding performance was benefiting from the synergetic effects of reduced aggregation of Fe3O4 combined with the enhanced adsorption capacity of PAM-AMPS hydrogel. Their cooperative function promoted oxidative decomposition of MB. In addition, PAM-AMPS/Fe3O4 exhibited a good stability and reusability, and it could maintain high degradation efficiency and activity after three successive cycling tests. And at the same time, the produced dominate oxidizing species for MB degradation in the system were identified as SO4•− by the radical quenching experiments. This work laid a foundation for applying PAM-AMPS/Fe3O4 as a highly efficient and stable catalyst for future applications and provided new insights into the design and synthesis of environmentally benign and inexpensive persulfate activators. [ABSTRACT FROM AUTHOR]

Cancer is a dreadful disease and among the prominent causes of death worldwide. The major reasons for the high mortality rate among cancer patients are elevated toxicity, improper oral bioavailability, hydrophobicity, low therapeutic indices, inconsistent circulation, nonspecific biodistribution and inefficiency, and inability to deliver therapeutic agents only to the target sites without inducing adverse effects on healthy tissues and organs. All this has prompted researchers to identify new agents that can treat and/or diagnose cancer efficiently. Apart from this, site-specific drug delivery is an important area of research that is expected to increase the efficacy of the therapeutics and thereby reduce its potential side effects. Recent advances in nanotechnology have opened a new arena in the field of theranostics as well as targeted drug delivery. Considerable work has been done, which has led to the development of non-invasive, efficacious therapeutics and diagnostics modalities as well as a targeted cancer treatment by using nanoscale metallic particles like gold. These gold nanoparticles which are being used in these applications are solid colloidal particles with a 10–100 nm range of size, unique physiochemical and optical properties, a sub-cellular size, and biocompatibility; therefore, they have theranostic potential and could retain and transport a therapeutic agent that is dispersed in a polymer carrier matrix, encapsulated within a polymer shell, covalently attached or adsorbed to the particle surface, or encapsulated within a structure. The review discusses the synthesis, unique properties, and wide spectrum of roles that gold-derived nanoparticles can perform in cancer diagnosis, targeted drug delivery, and therapeutics. Further clinical trials involving gold nanoparticles and the list of technologies that have got patented in cancer treatment and diagnosis have also been discussed. [ABSTRACT FROM AUTHOR]

In this paper, the effects of three coexisting ion systems (Cs, Sr), (Cr, Sr) and (Cs, Cr, Sr) on the adsorption of Sr(II) by irradiated Saccharomyces cerevisiae in solution were investigated. The three systems generally inhibited the adsorption of Sr(II) by yeast. The effects of several environmental factors on yeast adsorption of Sr(II) in coexisting ionic solutions were determined. Three adsorption models, Langmuir, Freundlich and Linear, were used to fit the experimental data. FTIR results showed that the mechanism by which Cs(I) and Cr(III) inhibited the adsorption of Sr(II) was related to the functional groups on the cell wall. [ABSTRACT FROM AUTHOR]

The unreasonable planning of land use in residential blocks affects the quality of the city and the comfort and convenience of urban residents. How to improve the vitality of the street from the source is an urgent problem to be solved in urban and rural planning disciplines. This paper selects 18 residential districts in Xi'an, and uses a multivariate linear stepwise regression to establish a relationship model between street vitality and intensive land use indices in three different periods of non-commuting, weekly commuting, and weekend. Using fuzzy evaluation techniques, the degree of land use intensification in different residential blocks was analyzed. Using the relational model and evaluation conclusions, the appropriate range of street vitality in residential blocks was determined, and the constructed model was used to obtain the suitable index range for intensive land use under street vitality. The results show that the street vitality and building density, the proportion of commercial space along the street and the red line width of the street are most affected during the non-commuting period during the week. The street vitality during the commute period is most closely related to the building density, building mix and street network density. Street dynamics are most closely related to building density, building mix, and street red line width during weekends. The conclusions of the study provide theoretical support and data support for the optimization and transformation of land use in residential blocks, and ultimately aim to stimulate street vitality and promote the realization of intensive land use in residential blocks. [ABSTRACT FROM AUTHOR]

Cucumber is an economically important horticultural crop that is highly dependent on nitrogen fertilizer. Nitrate is the main nitrogen source for cucumber; however, the effects of nitrogen signaling on the early-stage growth of cucumber seedlings and the related regulatory mechanisms are still unclear. To compare seedling growth status at different nitrate levels, we performed a growth experiment using cucumber seedlings that had nearly exhausted their nitrogen reserves under nitrogen deficiency conditions (NO3−-N/NH4+-N = 0 in MS medium). Using qPCR and in situ RNA hybridization localization of candidate CsNPF genes, we found that short-term nitrogen deficiency promoted changes in root vascular bundle morphology and xylem growth in cucumber seedlings, thereby enhancing their growth potential. Among the candidate genes, CsNPF7.2, a gene located in the vascular cambium was found to be induced by short-term nitrogen deficiency. Considering the abundance of vasculature development marker genes, we speculated that the function of CsNPF7.2 might relate to the development of vascular bundles in plants suffering from nitrogen stress. The objective of our study was to investigate the growth changes in cucumber seedlings in response to different nitrogen levels, and to examine the mRNA accumulation and expression patterns of nitrate transporter CsNPF genes, so that critical genes can be identified to improve nitrogen use efficiency in cucumber cultivation. The results of this study provides a novel theoretical basis for optimizing cultivation, regulating rational fertilization levels, and improving nitrogen use efficiency in production. In addition, our study also provides new avenues for the further study of the function of CsNPF7.2 on regulating vasculature development in response to nitrogen stress. [ABSTRACT FROM AUTHOR]

We proposed a numerical and theoretical research on the realization of the tunable plasmon-induced transparency (PIT) with ultra-broadband at terahertz frequencies in Dirac semimetal metamaterials. The effect of temperature on the PIT window was analyzed simultaneously. The magnetic dipole coupling between "bright mode" and "dark mode" leads to a novel PIT optical response. Simulation results show that the maximum bandwidth of PIT window can be increased to 426 GHz and 393 GHz by adjusting the dimensions of d1 and d2 in the Dirac asymmetrical structure, respectively. Moreover, we can dynamically tune the PIT window frequency from 1.257 to 1.508 THz by adjusting the Fermi energy from 70 to 90 meV. Furthermore, a positive group delay of about 0.75 ps can be obtained by varying the Fermi energy in the proposed structure. These results will bring a variety of potential applications in terahertz field. [ABSTRACT FROM AUTHOR]

To understand the ecological status and macrobenthic assemblages of the Xin’an River Estuary and its adjacent waters, a survey was conducted for environmental variables and macrobenthic assemblage structure in September 2012 (Yantai, China). Several methods are adopted in the data analysis process: dominance index, diversity indices, cluster analysis, non-metric multi-dimentional scaling ordination, AMBI and M-AMBI. The dissolved inorganic nitrogen and soluble reactive phosphorus of six out of eight sampling stations were in a good condition with low concentration. The average value of DO ((2.89±0.60) mg/L) and pH (4.28±0.43) indicated that the research area faced with the risk of ocean acidification and underlying hypoxia. A total of 62 species were identified, of which the dominant species group was polychaetes. The average abundance and biomass was 577.50 ind./m2 and 6.01 g/m2, respectively. Compared with historical data, the macrobenthic assemblage structure at waters around the Xin’an River Estuary was in a relatively stable status from 2009 to 2012. Contaminant indicator species Capitella capitata appeared at Sta. Y1, indicating the animals here suffered from hypoxia and acidification. AMBI and M-AMBI results showed that most sampling stations were slightly disturbed, which were coincided with the abiotic measurement on evaluating the health conditions. Macrobenthic communities suffered pressures from ocean acidification and hypoxia at the research waters, particularly those at Stas Y1, Y2 and Y5, which displays negative results in benthic health evaluation. [ABSTRACT FROM AUTHOR]

From a dataset of macrobenthos obtained from 18 cruises from 2004 to 2013 in the Huanghe (Yellow River) Estuary and its adjacent areas, the composition and characteristics of macrobenthos were analyzed, and the applicability of the Shannon-Wiener Index ( H′), AZTI's Marine Biotic Index (AMBI) and multivariate AMBI (MAMBI) for assessing benthic habitat quality was compared. The results showed a total of 203 macrobenthos in the study area. The macrobenthos were dominated by polychaetes, followed by mollusks and crustaceans. The macrobenthic ecological groups were dominated by EGI, EGII and EGIII, which respectively accounted for 31.5%, 36.0% and 21.2% of the total. There were significant differences between the evaluation results of the three indices. The ecological quality status (EQS) levels given by the AMBI were greater than those given by the H′ and M-AMBI. The AMBI could not reflect the differences between 11 sites but the H′ and M-AMBI could do. Moreover, the three indices responded well to the variations in salinity (S) and dissolved oxygen (DO) in the waters. The H′ and M-AMBI also responded sensitively to the differences in physical parameters, such as water depth and sediment texture. The correlation between M-AMBI and environmental pressure gradient data was the strongest. The MAMBI could effectively distinguish degraded conditions from undegraded but the H′ and AMBI could not. Therefore, the M-AMBI reflected benthic habitat health well in the study areas. However, the objectivity of evaluation results of M-AMBI needs further verification by physical, chemical and biological methods. The thresholds also need further discussion. [ABSTRACT FROM AUTHOR]

Multivariate AZTI's Marine Biotic Index (M-AMBI) was designed to indicate the ecological status of European coastal areas. Based upon samples collected from 2009 to 2012 in the Bohai Bay, we have tested the response of variations of M-AMBI, using biomass (M-BAMBI) in the calculations, with different transformations of the raw data. The results showed that the ecological quality of most areas in the study indicated by M-AMBI was from moderate to bad status with the worse status in the coastal areas, especially around the estuaries, harbors and outfalls, and better status in the offshore areas except the area close to oil platforms or disposal sites. Despite large variations in nature of the input data, all variations of M-AMBI gave similar spatial and temporal distribution patterns of the ecological status within the bay, and showed high correlation between them. The agreement of new ecological status obtained from all M-AMBI variations, which were calculated according to linear regression, was almost perfect. The benthic quality, assessed using different input data, could be related to human pressures in the bay, such as water discharges, land reclamation, dredged sediment and drilling cuts disposal sites. It seems that M-BAMBI were more effective than M-NABMI (M-AMBI calculated using abundance data) in indicating human pressures of the Bay. Finally, indices calculated with more severe transformations, such as presence/absence data, could not indicate the higher density of human pressures in the coastal areas of the north part of our study area, but those calculated using mild transformation (i.e., square root) did. [ABSTRACT FROM AUTHOR]

The protection of the biological diversity and the maintenance of the regional ecological integrity for the Huanghe (Yellow River) Estuary and its adjacent areas are practically significant and valuable. However, frequent human activities and natural climate changes have caused vigorous disturbances on the ecosystem in these sea areas. An objective assessment on the benthic habitat quality (BHQ) of the Huanghe Estuary and its adjacent areas is conducted, using AZTI's Marine Biotic Index (AMBI) and multivariate AMBI (M-AMBI) based on the data of macrobenthos in May and August 2011. The results show that both the indices do not correlate significantly, and their assessment results are greatly different. All of the samples assessed using the AMBI were 'high' or 'good', because the ecological group I (EGI) and the ecological group II (EGII) were dominant macrobenthic ecological groups in the research area. Owing to a low species' richness and a high individual abundance in some samples, the BHQ levels using the M-AMBI were worse than those of the AMBI. Significant correlations are observed between the M-AMBI, water depth, bottom water salinity and dissolved inorganic nitrogen, thus the M-AMBI could sensitively respond to environmental changes and distinguish influences from uninfluenced stations, but the AMBI could not. The consistent results between the AMBI and the M-AMBI mainly appeared in the uninfluenced (undisturbed or slightly disturbed) stations. Therefore, the M-AMBI is more effective than the AMBI in assessing the benthic habitat quality in the Huanghe Estuary and its adjacent areas. Using the M-AMBI to assess the BHQ of the Huanghe Estuary and its adjacent areas, the results show that 3% of the stations are undisturbed and the BHQs are 'high', and 61% of the stations are slightly disturbed and those of the BHQ are 'good', and the rest are meanly disturbed and those of the BHQ are 'moderate'. [ABSTRACT FROM AUTHOR]