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Learning design has become increasingly important in the context of expanding and dynamic digital learning environments. More traditional teaching approaches are no longer sufficient to engage learners in these changing learning environments. Teachers and aspiring learning designers therefore increasingly need learning design expertise, which takes time to develop. This paper responds to this challenge by outlining a fishbone digital learning design method, which is aligned with updated versions of Bloom's taxonomy for the digital world, as a scaffolded approach to developing basic learning design expertise. The study integrates three practical tools into one learning design method to ensure constructive alignment. The findings contribute to digital educational development and teacher professional development by proposing a practical and easy to adapt learning design method. [ABSTRACT FROM AUTHOR]

Polyester is extensively used in the textile industry for fabricating fibers and fabrics. Dyeing for polyester fabrics has a huge demand. Given that dyeing is one of the least environmentally friendly industrial processes, decreasing the attempts for dyeing (a.k.a realizing "one-shot" successful dyeing) is of vital importance to the dyeing manufacturing for polyester fabrics. This can be achieved by accurately predicting the dye concentrations for a dyeing recipe with provided target color information on the polyester fabrics. In this paper, we report a data-driven approach for accurately predicting industrial dyeing recipes of polyester fabrics. We intensively discuss the data preprocessing skills for this purpose. We show that log-transform and using full reflectance spectra for the color as input are two effective preprocessing techniques to improve the model performance. An effective model based on gradient-boosting regression tree (GBRT) has been developed to quantitatively model the relationship between the colorimetric information and the dye concentrations of industrial dyeing data of polyester fabrics. The developed approach can predict dye concentrations for dyeing tasks for polyester fabrics with error at 10–20%. [ABSTRACT FROM AUTHOR]

This paper examines whether financial technology (FinTech) development affect household energy consumption. The proposed point that FinTech can reduce household energy consumption is theoretically discussed and empirically tested using data from the 2017 Digital Financial Inclusion Index, the 2018 China Family Panel Studies (CFPS), the 2018 China Environmental Statistical Yearbook and the 2018 China Science and Technology Statistical Yearbook. The results show that FinTech contributes to reducing household energy consumption. Several retests, including the instrumental variable, replacement sample and propensity score matching methods, prove its robustness. Mechanism tests show that investment in environmental governance and technological innovation promotion are the two main transmission channels. We also find that the reducing effect is more significant in the following groups: the low-middle income level classes, the eastern regional residents, those with bachelor's degrees and above, the those aged over 60 and rural residents. The outcomes of this paper call for government departments to positively guide FinTech development to reduce household energy consumption. From another perspective, the conclusions drawn from our analysis make a great reference value for countries and provide new ideas for Chinese carbon peaking and carbon neutralisation goals. [ABSTRACT FROM AUTHOR]

Purpose: Prebiotics, including fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS), stimulate beneficial gut bacteria and may be helpful for patients with Alzheimer's disease (AD). This study aimed to compare the effects of FOS and GOS, alone or in combination, on AD mice and to identify their underlying mechanisms. Methods: Six-month-old APP/PS1 mice and wild-type mice were orally administered FOS, GOS, FOS + GOS or water by gavage for 6 weeks and then subjected to relative assays, including behavioral tests, biochemical assays and 16S rRNA sequencing. Results: Through behavioral tests, we found that GOS had the best effect on reversing cognitive impairment in APP/PS1 mice, followed by FOS + GOS, while FOS had no effect. Through biochemical techniques, we found that GOS and FOS + GOS had effects on multiple targets, including diminishing Aβ burden and proinflammatory IL-1β and IL-6 levels, and changing the concentrations of neurotransmitters GABA and 5-HT in the brain. In contrast, FOS had only a slight anti-inflammatory effect. Moreover, through 16S rRNA sequencing, we found that prebiotics changed composition of gut microbiota. Notably, GOS increased relative abundance of Lactobacillus, FOS increased that of Bifidobacterium, and FOS + GOS increased that of both. Furthermore, prebiotics downregulated the expression levels of proteins of the TLR4-Myd88-NF-κB pathway in the colons and cortexes, suggesting the involvement of gut–brain mechanism in alleviating neuroinflammation. Conclusion: Among the three prebiotics, GOS was the optimal one to alleviate cognitive impairment in APP/PS1 mice and the mechanism was attributed to its multi-target role in alleviating Aβ pathology and neuroinflammation, changing neurotransmitter concentrations, and modulating gut microbiota. [ABSTRACT FROM AUTHOR]

This study aims to investigate the role of arbuscular mycorrhizal (AM) symbiosis in reducing N loss from paddy fields, using two rice lines: a mycorrhiza-defective rice line (non-mycorrhizal) and its mycorrhizal progenitor. Two rice lines were grown in the presence of an AM fungal isolate. In this study, N loss of runoff, leaching, N2O emission, and NH3 volatilization were measured, and in addition, N uptake of rice, soil aggregates, and plant available N concentration of soil. The results obtained suggest that N loss via runoff, leaching, NH3 volatilization, and N2O emission of mycorrhizal rice was 11%, 8%, 6%, and 1%, lower than that of non-mycorrhizal rice, respectively. Meanwhile, mycorrhizal rice has higher biomass and plant N uptake. Our study shows that the AM symbiosis contributes to the sustainability of rice production by reducing N loss, enhancing soil aggregation and increasing plant N uptake. [ABSTRACT FROM AUTHOR]

The artificial ground freezing (AGF) method has been widely used in underground engineering construction. As the main load-bearing elements of the AGF method, the strength of frozen walls is expected to play a crucial role in engineering stability. To improve the accuracy of quantitative evaluations of engineering stability, it is necessary to grasp the strength characteristics of frozen rock during service. To achieve this, the red sandstone taken from a frozen shaft project was tested via triaxial compression at different temperatures (−5°C,−10°C,−15°C,−20°C,−25°C, and −30°C). After that, a damage constitutive model with a Weibull distribution was derived to characterize the damage development of the frozen sandstone. Based on the validated model, the variation of damage degree was analyzed. The results show that the crack initiation stress, crack dilation stress, and peak strength all increase with decreasing temperature. The crack damage threshold increases as the frozen sandstone strength increases. The presented damage constitutive model can reflect the damage evolution of frozen sandstone. When the stress exceeds the crack initiation stress, the damage degree begins to increase, and it increases quickly when the stress approaches the peak strength. The model parameters can reflect the influence of negative temperatures on the strength of frozen sandstone. The crack damage threshold could be treated as an essential intrinsic property for predicting the failure process of frozen sandstones. The results can provide an important reference for the design and construction of frozen ground engineering. [ABSTRACT FROM AUTHOR]

The power sector continues to accumulate a large amount of data resources, including relevant standard specifications, technical documents, management documents, fault resolution records. How to quickly query and intelligently search these documents is of great value for grid dispatching and fault recovery. The domain search system of traditional power grid is based on keywords, and has the problems of low precision and recall rate. It cannot understand the business language and cannot support semantic reasoning. This paper designs and implements a method based on knowledge mapping to construct the power domain semantic search system. Semantic knowledge extraction of unstructured data is carried out by intelligent domain segmentation technology, organized and stored as knowledge mapping, and semantic search for support reasoning is realized based on knowledge mapping. The process of constructing domain semantic search system is introduced. Experiments show that the accuracy rate and recall rate of the method have been greatly improved. [ABSTRACT FROM AUTHOR]

Aims: Phosphorus (P) loss from paddy fields is a significant issue in sustainable rice production by threatening water environments. We aimed to examine the suitability of mycorrhiza-defective rice (non-mycorrhizal) and its mycorrhizal progenitor to evaluate P loss control via arbuscular mycorrhizal (AM) fungi. We also aimed to investigate the AM effect on P loss via runoff and leaching. Methods: We grew the two rice lines in microcosms with and without AM fungi, measured P loss via runoff and leaching before and after nitrogen–phosphorus–potassium fertilization, and quantified plant P content and soil P concentration after the final harvest. Results: Mycorrhizal and non-mycorrhizal rice pair systems in the absence of AM fungi had similar plant, soil, runoff, and leachate P contents (except PO43−). In the presence of AM fungi, the concentrations of all P forms in runoff water and leachate in mycorrhizal rice were lower than those in nonmycorrhizal rice regardless of their solubility in water and availability to plants. The cumulative P loss from mycorrhizal systems was 10% less than that from their nonmycorrhizal counterparts. Conclusions: This mycorrhizal/non-mycorrhizal rice pair is an efficient experimental tool for research on the control of P loss from paddy fields with AM fungi. AM colonization contributes to the sustainability of rice production by decreasing P loss from paddy fields. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi were of importance in mitigating soil erosion, which was highly influenced by biotic and abiotic factors, such as host plant growth and soil nutrient. To investigate the impact of nitrogen (N) fertilization on seasonal variance in AM colonization and soil erosion, we conducted a field experiment with rice cultivation under four N fertilizer levels (0 kg N ha−1, 270 kg N ha−1, 300 kg N ha−1, and 375 kg N ha−1 plus organic fertilizers) in the Taihu Lake region, China. We investigated AM colonization before rice transplantation, during rice growth, and after rice harvest. We also assessed soil splash erosion of intact soil cores sampled at tillering and after rice harvest. We found that AM colonization (indicated by percentage of root length colonization) varied from 15 to 73%, which was attributed to rice growth, N fertilization, and their interaction. Soil loss due to splash erosion was cut down by organic N fertilizer at tillering, while higher inorganic N fertilization significantly increased soil loss after rice harvest. Additionally, we found significantly negative relationships of AM colonization to soil loss but positive relationships to soil aggregate stability. We highlighted the potential role of AM fungi in decreasing soil erosion and suggested that high N fertilization should be considered carefully when seeking after high yields. [ABSTRACT FROM AUTHOR]

Main conclusion: Trehalose increased drought tolerance of tomato plants, accompanied by reduced water loss and closed stomata, which was associated with the upregulated ABA signaling-related genes expression, but not in ABA accumulation. Drought is one of the principal abiotic stresses that negatively influence the growth of plant and yield. Trehalose has great agronomic potential to improve the stress tolerance of plants. However, little information is available on the role of ABA and its signaling components in trehalose-induced drought tolerance. The aim of this study is to elucidate the potential mechanism by which trehalose regulates ABA in response to drought stress. In this study, 6-week-old tomato (Solanum lycopersicum cv. Ailsa Craig) plants were treated with 0 or 15.0 mM trehalose solution. Results showed that trehalose treatment significantly enhanced drought tolerance of tomato plants, accompanied by encouraged stomatal closure and protected chloroplast ultrastructure. Compared with controls, trehalose-treated plants showed lower hydrogen peroxide content and higher antioxidant enzymes activities, which contributed to alleviate oxidative damage caused by drought. Moreover, trehalose treatment decreased ABA content, which was followed by the downregulation of ABA biosynthesis genes expression and the upregulation of ABA catabolism genes expression. In contrast, exogenous trehalose upregulated transcript levels of ABA signaling-related genes, including SlPYL1/3/4/5/6/7/9, SlSnRK2.3/4, SlAREB1/2, and SlDREB1. These results suggested that trehalose treatment enhanced drought tolerance of tomato plants, and it's ABA signaling rather than ABA metabolism that was involved in trehalose-induced drought tolerance in tomato plants. These findings provide evidence for the physiological role of trehalose and bring about a new understanding of the possible relationship between trehalose and ABA. [ABSTRACT FROM AUTHOR]

Novel Sb3+-doped Ag/AgCl photocatalysts containing different fractions of Sb3+ were synthesized by a simple coprecipitation method and systematically characterized by many techniques. The activity was maximized at the dosage of 2 wt% Sb3+ in methyl orange (MO) photodegradation experiments, and was reserved after three cycles. The photocatalytic activity was decided by the effective separation and low recombination rate of photogenerated electron-hole pairs. The high activities theoretically contributed to the Sb3+-induced formation of chloride dangling bonds and vacancies. The activity of Sb3+-doped Ag/AgCl (2 wt%) maximized to 98% after 14 min, which was much higher than the 50% of pure Ag/AgCl. Electron spin resonance and photoluminescence spectrum showed ·OH was the main active species during the MO oxidation over Sb3+-doped Ag/AgCl. [ABSTRACT FROM AUTHOR]

A novel sonocatalyst CdS was prepared by a facile precipitation method, and characterized by X-ray powder diffraction, transmission electron microscopy, UV-vis absorption spectroscopy, and photoluminescence spectroscopy. Comparative sonocatalytic degradation experiments were carried out in different conditions under ultrasonic irradiation and with rhodamine B (RhB) used as the model substrate. Results indicate that CdS is a highly active sonocatalyst. The efficiency of RhB sonodegradation in aqueous solutions within 4 h is up to 70% after the addition of CdS. Abundant •OH during the RhB sonodegradation was detected, which may be responsible for the high sonodegradation rate over CdS under ultrasonic radiation. [ABSTRACT FROM AUTHOR]

Pure WO3 powder was prepared from a simple method and applied into sonocatalytic degradation of rhodamine B (RhB), the model compound. The structure and properties of samples were characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) absorption spectroscopy, and photoluminescence (PL) spectroscopy. We studied the effects of WO3 on the sonocatalytic degradation of RhB and the operational parameters such as catalyst dosage and RhB concentration. The experimental results showed that the best sonocatalytic degradation ratio (59.39%) of organic dyes could be obtained when the optimal conditions of 10.00-mg/L initial concentration, 3.00-g/L prepared WO3 powder added amount, 99-W ultrasound output power, and 270-min ultrasonic irradiation were adopted. Under ultrasonic conditions, the degradation rate after addition of WO3 reached the highest activity of 57.9%, and about three times the rate of degradation was not added. Abundant ·OH was induced by WO3 powder under ultrasonic irradiation, which may be the main contributor to the high sonodegradation rate. [ABSTRACT FROM AUTHOR]

Nowadays, the use of non- Saccharomyces yeasts in combination with Saccharomyces cerevisiae is being recognised to enhance the analytical composition of the wines. The aim of this work was to evaluate the influence of indigenous non- Saccharomyces yeasts on the flavour character of wines from the cool-climate grape cultivar Solaris in Denmark. The volatile and non-volatile compounds as well as the sensory properties of wines were evaluated. Solaris wines with Hanseniaspora uvarum sequentially inoculated with S. cerevisiae produced a larger amount of glycerol as well as heptyl acetate and 2-phenylethyl acetate. This co-culture fermentation also produced higher amounts of ethyl acetate and acetic acid, reducing the possibility of its use in winemaking. Three Metschnikowia strains, a M. chrysoperlae strain and two M. fructicola strains, gave a comparable production of volatile compounds. These wines were characterised by several floral and fruity attributes. The Metschnikowia strains turned out to be promising in winemaking from Solaris grapes. [ABSTRACT FROM AUTHOR]

Low-cost and environmentally friendly mediators could facilitate the application of laccase (EC 1.10.3.2) in variant biotechnological processes. Acetylacetone (AA) represents an inexpensive and low toxic small molecular diketone that has been proven as an effective mediator for laccase in free radical polymerization. However, the potential of AA as a mediator for laccase in pollutant detoxification and/or degradation is still unknown. In this work, the roles of AA in laccase-induced polymerization and transformation were investigated. AA was demonstrated to be a highly efficient mediator in the laccase-induced grafting copolymerization of acrylamide and chitosan. The efficacy of AA in the laccase-induced decoloration of malachite green (MG) was compared with that of the widely used 1-hydroxybenzotriazole (HBT). The laccase-AA system had the highest turnover number (TON, 39.1 μmol/U), followed by the laccase-only system (28.5 μmol/U), while the TON of the laccase-HBT system was the lowest (14.9 μmol/U). The pseudo-first-order transformation rate constant ( k) of MG in the laccase-AA system was up to 0.283 h under the given conditions, while the k of AA caused by laccase was only 0.008 h. In the five-cycle run, the concentration of AA remained stable. The larger TON of the laccase-AA system and the stability of AA in the cycling runs demonstrate that AA was more recyclable than HBT in the LMS, leading to a prolonged serving life of laccase. These results suggest that AA might be a potential redox mediator for laccase. [ABSTRACT FROM AUTHOR]

Lifetime is a key index in the evaluation of environmentally functional materials. Although it is well known that adsorption is the first step in photo-catalysis, very little work has been done on the sequential use of materials as both adsorbents and photocatalysts. In this work, two titania-based materials, TiO xerogel and TiO photocatalyst nanoparticles, were fabricated and evaluated as adsorbent and photocatalyst for the remediation of contaminated water with an azo dye, Acid Orange 7 (AO7), as the modeling pollutant. The TiO xerogel showed a high adsorption capacity to AO7 (769 mg/g) and could be regenerated easily with diluted NaOH solution (0.01 mol/L) for several cycles. The exhausted xerogel was calcined at 400 °C for 3 h and used as a photocatalyst for the degradation of AO7. Compared to the nanoparticles directly prepared from fresh TiO xerogel, the TiO nanoparticles from adsorption exhausted xerogel showed a much higher photocatalytic activity upon both UV and visible light irradiation. Thus the titania-based materials were endowed with improved performance as well as prolonged lifetime. [ABSTRACT FROM AUTHOR]

A zero-valent iron (ZVI)-resin composite (D201-ZVI) has been proven as an effective arsenic removal material. Here, the effect of ZVI distribution and aging on the reactivity of the hybrid composite was investigated by comparing the As(III) removal performances of freshly synthesized and aged D201-ZVI composites. The ZVI distribution and structures of these composites were characterized using X-ray diffraction, X-ray photoelectron spectrometry, and scanning electron microscope equipped with an energy-dispersive X-ray analyzer (SEM-EDX). After aging in aerated water for 96 h, the ZVI distribution in the aged composites did not change significantly, which was confirmed by SEM-EDX. However, the Fe content decreased as the aging time increased. Among the as-prepared composites with variant ZVI distributions, the hybrids with more uniform ZVI distribution exhibited higher removal efficiency and faster reaction rate. Experimental results show that the D201-ZVI gradually lost reactivity with an increase in aging time from 24 to 96 h. The effects of aging time on the speciation of As suggest that the reduced As(III) removal efficiency was attributable to the decrease of the Fe content. Furthermore, the importance of the ZVI distribution is proposed to explain the aging effect. [ABSTRACT FROM AUTHOR]

Freeze-thaw action is a complex moisture-heat-mechanics interaction process, which has caused prevailing and severe damages to canals in seasonally frozen regions. Up to now, the detailed frost damage mechanism has not been well disclosed. To explore the freeze-thaw damage mechanism of the canal in cold regions, a numerical moisture-heat-mechanics model is established and corresponding computer program is written. Then, a representative canal in the northeast of China is taken as an example to simulate the freeze-thaw damage process. Meanwhile, the robustness of the numerical model and program is tested by some in situ data. Lastly, the numerical results show that there are dramatic water migration and redistribution in the seasonal freeze-thaw variation layer, causing repetitive frost heave and thaw settlement, and tension-compression stresses. Therefore, the strengths of soil are reduced after several freeze-thaw cycles. Further, the heavy denudation damage and downslope movement of the canal slope would be quite likely triggered in seasonally frozen regions. These zones should be monitored closely to ensure safe operation. As a preliminary study, the numerical model and results in this paper may be a reference for design, maintenance, and research on other canals in seasonally frozen regions. [ABSTRACT FROM AUTHOR]

The aim was to develop a liposomal oxymatrine conjugating d-alpha tocopheryl polyethylene glycol 1000 succinate (OMT-LIP) for enhanced therapeutics of hepatic fibrosis. OMT-LIP was prepared using the remote loading method. The influences of formulation compositions on the encapsulation efficiency of OMT-LIP were investigated. Mean particle size, zeta potential, morphology, in vitro release, fibrotic liver targeting, and therapeutics of OMT-LIP were thoroughly assessed. The intraliposomal buffer composition and concentration, extraliposomal phase composition and pH, types of phospholipid, lipid molar ratio composition, and theoretical drug loading are crucial factors to entrap OMT into liposomes. The optimum OMT-LIP presented spherically unilamellar microstructures with entrapment efficiency of 79.7 ± 3.9%, mean particle size of 121.6 ± 52.9 nm, and zeta potential of −5.87 mV. OMT-LIP significantly increased the accumulation of OMT in the fibrotic liver with an 11.5-fold greater AUC than OMT solution in the dimethylnitrosamine (DMN)-induced hepatic fibrosis animals. OMT-LIP could be a potential strategy to improve treatment outcomes for hepatic fibrosis, showing the protective effects to mice given CCl and the enhanced therapeutics to mice with either DMN or CCl-induced hepatic fibrosis. [ABSTRACT FROM AUTHOR]

It has been shown that a volume discharge is forming in non-uniform electric-field rough cathode and even anode without pre-ionization in SF and CH mixtures. The discharge is presented with many diffuse channels attached to bright circular cathode spots that diverge towards the anode, with the channels overlapping, form a spatially uniform glow discharge. Self-Initiated Volume Discharge (SIVD) has been performed at a total mixture pressure up to 8 kPa and energy deposition up to 200 J/L. The experimental results indicate that Self-Sustained Volume Discharge (SSVD) in SF and CH mixtures develops in the form of SIVD, which is promising for creation of high energy and pulse-periodic HF laser. [ABSTRACT FROM AUTHOR]

Tl(I) in water even at a trace level is fatal to human beings and the ecosystem. Here we fabricated a new polymer-supported nanocomposite (HMO-001) for efficient Tl(I) removal by encapsulating nanosized hydrous manganese dioxide (HMO) within a polystyrene cation exchanger (D-001). The resultant HMO-001 exhibited more preferable removal of Tl(I) than D-001 and IRC-748, an iminodiacetic chelating polymer, particularly in the presence of competing Ca(II) ions at greater levels in solution. Such preference was ascribed to the Donnan membrane effect caused by D-001 as well as the specific interaction between Tl(I) and HMO. The adsorbed Tl(I) was partially oxidized into insoluble Tl(III) by HMO at acidic pH, while negligible oxidation was observed at circumneutral pH. The exhausted HMO-001 was amenable to efficient regeneration by binary NaOH-NaClO solution for at least 10-cycle batch runs without any significant capacity loss. Fixed-bed column test of Tl(I)-contained industrial effluent and natural water further validated that Tl(I) retention on HMO-001 resulted in a conspicuous concentration drop from 1.3 mg/L to a value lower than 0.14 mg/L (maximum concentration level for industrial effluent regulated by US EPA) and from 1-4 μg/L to a value lower than 0.1 μg/L (drinking water standard regulated by China Health Ministry), respectively. [ABSTRACT FROM AUTHOR]

In this study, BiPO:Eu phosphors were synthesized by a facile hydrothermal route at different temperatures. The BiPO:Eu particles were characterized by x-ray powder diffraction (XRD), infrared spectra, and luminescence spectroscopy. The XRD results reveal that the BiPO:Eu particles present different phases for different hydrothermal temperatures. It is found that a hexagonal phase is formed at 100°C, which transforms to a low-temperature monoclinic phase (MP) when the hydrothermal temperature is increased to 150°C. This low-temperature MP transforms to high-temperature MP when the temperature is increased beyond 200°C. The luminescent properties of the BiPO:Eu particles were studied using an excitation wavelength of 270 nm. The emission spectra display the bands associated with the D → F ( J = 1, 2, 3, and 4) electronic transitions of the Eu cations. The intensity of the emission spectra increases with increasing hydrothermal temperature. These results demonstrate that BiPO:Eu with different phases can be obtained through the hydrothermal method, which may enrich the solution chemistry for preparation of advanced materials with tailored functionality. [ABSTRACT FROM AUTHOR]

There are limited data on trace metals in the fishes of the Tibetan Plateau. In this study, 62 fish samples were collected from six alpine lakes and a river to investigate the levels and spatial variations of trace metals across the Tibetan Plateau. The concentrations of nine trace elements in fish samples were measured using an inductively coupled plasma mass spectrometer after microwave digestion. Results showed the metal concentrations in the fish muscles had the following ranges: Cr 0.09-0.74 mg/kg, Mn 0.38-4.49 mg/kg, Ni 0.06-0.91 mg/kg, Cu 1.00-32.2 mg/kg, Zn 13.1-102.5 mg/kg, As 0.12-3.10 mg/kg, Pb 0.46-3.22 mg/kg, Ba 0.60-4.93 mg/kg, and Se 0.77-9.38 mg/kg on a dry weight basis, respectively. All the lake-averaged metal concentrations in the fish muscle were below the maximum permissible levels set by the Chinese food health criterion (GB2762-2012). The results were analyzed by multivariate statistical techniques to identify the major factors explaining the variance of metal concentrations in the alpine lakes. This work provides baseline data on metal pollution in common fish species of the Tibetan Plateau, contributing to the effective evaluation of both the environmental quality and health status of organisms in the aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Chemical and microbial methods are the main remediation technologies for chromium-contaminated soil. These technologies have progressed rapidly in recent years; however, there is still a lack of methods for evaluating the chemical and biological quality of soil after different remediation technologies have been applied. In this paper, microbial remediation with indigenous bacteria and chemical remediation with ferrous sulphate were used for the remediation of soils contaminated with Cr(VI) at two levels (80 and 1,276 mg kg) through a column leaching experiment. After microbial remediation with indigenous bacteria, the average concentration of water-soluble Cr(VI) in the soils was reduced to less than 5.0 mg kg. Soil quality was evaluated based on 11 soil properties and the fuzzy comprehensive assessment method, including fuzzy mathematics and correlative analysis. The chemical fertility quality index was improved by one grade using microbial remediation with indigenous bacteria, and the biological fertility quality index increased by at least a factor of 6. Chemical remediation with ferrous sulphate, however, resulted in lower levels of available phosphorus, dehydrogenase, catalase and polyphenol oxidase. The result showed that microbial remediation with indigenous bacteria was more effective for remedying Cr(VI)-contaminated soils with high pH value than chemical remediation with ferrous sulphate. In addition, the fuzzy comprehensive evaluation method was proven to be a useful tool for monitoring the quality change in chromium-contaminated soils. [ABSTRACT FROM AUTHOR]

A polystyrene-based ion-exchange resin was employed as the precursor for preparation of resin-derived carbon spheres (RCSs) through KOH activation with various impregnation ratios. Pore structure, yield and hardness, surface functional groups of the samples and their adsorption performance towards dibenzothiophene (DBT) were investigated. The RCSs with large surface areas (up to 2696 m/g) and total pore volumes (up to 1.46 cm/g) exhibited larger adsorption capacities than a commercial activated carbon, F400. Polanyi-Dubinin-Mane (PDM) model was applied to fit the adsorption data, which proved that micropore filling was involved during the adsorption process. Moreover, a good linear relationship was observed between the extra-micropore volume and adsorption capacity. Intra-particle diffusion (IPD) model was used to describe the kinetic data of DBT onto the adsorbents. The adsorption processes were divided into three stages according to the different diffusion parameter. The selective adsorption towards DBT in the presence of competing compounds was also investigated and the high selectivity of the RSCs towards DBT may be attributed to the large quantity of acidic oxygen-containing groups. [ABSTRACT FROM AUTHOR]

Adsorption is controlled by an array of attractive forces between adsorbent, adsorbate, and solvent molecules. Such forces work interactively, making the interpretation and prediction of sorption processes difficult. By carefully designing the experimental matrix, the effects of adsorbent surface chemistry and pore structure on the adsorption of aromatic compounds were isolated from the complicated web of interactions. Two parameters, γ and δ, were created to describe the relative adsorption affinity index of activated carbons to adsorbates and the occupancy rate of activated carbons by active sites that can lead to formation of water clusters. Taking the space availability and the relative adsorption affinity index into account, a correlation between the Freundlich adsorption affinity coefficient and the characteristics of adsorbent was established. With this correlation, if the Freundlich adsorption affinity coefficient of a compound on one carbon is known, its adsorption affinity coefficient on another carbon might be predictable if the surface chemistries and pore structures of both carbons are available. [ABSTRACT FROM AUTHOR]

By encapsulating zirconium phosphate (ZrP) nanoparticles into three macroporous polystyrene resins with various surface groups, i.e., −CHCl, −SO, and −CHN(CH) three nanocomposite adsorbents (denoted as ZrP-Cl, ZrP-S, and ZrP-N) were fabricated, respectively for lead removal from water. Effect of the functional groups on nano-ZrP dispersion and effect of ZrP immobilization on the mechanical strength of the resulting nanocomposites were investigated. The presence of the charged functional groups (−SO and −CHN(CH)) are more favorable than the neutral −CHCl group to improve nano-ZrP dispersion (i.e., to achieve smaller ZrP nanoparticles). ZrP-N and ZrP-S had higher capacity than ZrP-Cl for lead removal. As compared to ZrP-N, ZrP-S exhibits higher preference toward lead ion at high calcium levels as a result of the potential Donnan membrane effect. On the other hand, nano-ZrP immobilization would simultaneously reinforce both the compressive strength and the wear performance of the resulting nanocomposites with the ZrP loadings up to 5 wt%. The results reported herein would shed some light on the generation of environmental nanocomposites with high capacity and excellent mechanical strength. [ABSTRACT FROM AUTHOR]

To utilize visible light more efficiently in photocatalytic reactions, Bi2O3/CaO photocatalysts were prepared by a mechanical mixing method and characterized by X-ray diffraction (XRD) and UV–vis spectroscopy. UV–vis spectroscopy results showed that the photocatalysts have a wide absorption band in the range of visible light. The photocatalytic activities of obtained Bi2O3, CaO, and Bi2O3/CaO samples were evaluated by methylene blue degradation under visible light irradiation. It was found that the Bi2O3/CaO sample exhibited the highest photocatalytic activity. [ABSTRACT FROM AUTHOR]

Pyrene was chemically assembled on a glass plate surface in a monolayer manner via spacers containing triethylenetetramine (TETA) subunits. It has been demonstrated that the fluorescence emission of the film is sensitive to the presence of trace amount of nitroaromatic compound (NAC) vapors. As discovered in the present work, the response selectivity of the pyrene-functionalized film depends on the length of the spacer, the vapor pressure of a given NAC, and the quencher size. The film shows faster response to those quenchers which have higher vapor pressure and smaller size. Compared to the film with shorter spacers, the present film with longer flexible spacers shows a slower response to the NACs, but higher selectivity to the quencher size. Additionally, the detection limits to common explosives in vapor phase, 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT), are 7.14×10-12 and 5.49×10-11 g·mL-1, respectively. Further examinations indicated that the sensing process is fully reversible, and the vapors of those common interference such as benzene, toluene, ethanol, and perfume have little effect upon the sensing performances of the film. [ABSTRACT FROM AUTHOR]

Reports on the calculation of the temperature distribution of Qing-Tibet railway embankment by deriving the finite element formula for heat convection in porous media using Galerkin's method. Analysis of the temperature fields of the traditional ballast embankment and the ripped-stone mass embankment; Damage to the railway embankment from permafrost degradation.

By using time-resolved kinetic spectrophotometry and pulse radiolysis technique, the oxidation of Phe by SO4 - radical has been investigated both in aqueous and water/acetonitrile mixed solutions. The results reveal that attack of the oxidizing SO4 - radical on Phe leads directly to the formation of Phe cation radical 3 with a strong absorption peak at 310 nm, then it proceeds in three competitive reactions via either hydroxylation, deprotonation or decarboxylation, which were found to be strongly dependent upon the ionization state of the substitutes —COOH and —NH2 and the nature of the solvents. Decarboxylation takes place only when the carboxyl group is deprotonated. At high pH deprotonation of Phe cation radical 3 is much easier to occur than that in neutral or acid solutions. Moreover, with addition of acetonitrile, deprotonation is more predominant than hydroxylation, whereas in aqueous solutions hydroxylation is much easier to occur. [ABSTRACT FROM AUTHOR]

Spike length (SL), fertile spikelet number per spike (SNS), thousand grain weight (TGW) and plant height (PH) are important agronomic traits related to yield in wheat. By the 55 K SNP assay, we constructed a high-density genetic linkage map with 186 F6 recombinant inbred lines developed between Chinese landrace wheat Banmangzi and an elite variety Jimai 22. Eighteen QTLs for SL, SNS, TGW and PH were detected. A new stable major QTL for SL was located on chromosome 2DS, with physical position 19.6 Mb and explaining 20.1–27.9% of the phenotypic variances in three environments, with the favorable allele from Banmangzi. And the QTL was co-located with QSNS.saas-2D.1 and QPH.saas-2D.2 which were detected in two environments and explained up to 18.5% of phenotypic variances for SNS. In addition, an major QTL for TGW was detected on chromosome 6AS, explaining 14.6–22.3% of the phenotypic variances in three environments. Four candidate genes for yield-related traits were identified, encoding IAA-amino acid hydrolase ILR1 and growth-regulating factor for SL, flowering promoting factor-like 1 and sucrose-phosphate synthase for TGW, respectively. [ABSTRACT FROM AUTHOR]

Copy number alteration (CNA) is known to induce gene expression changes mainly through dosage effect, and therefore affect the initiation and progression of tumor. However, tumor samples exhibit heterogeneity in gene dosage sensitivity due to the complicated mechanisms of transcriptional regulation. Currently, no high-throughput method has been available for identifying the regulatory factors affecting the functional consequences of CNA, and determining their effects on cancer. In view of the important regulatory role of miRNA, we investigated the influence of miRNAs on the dosage sensitivities of genes within the CNA regions. By integrating copy number, mRNA expression, miRNA expression profiles of three kinds of cancer, we observed a tendency for high dosage-sensitivity genes to be more targeted by miRNAs in cancer, and identified the miRNAs regulating the dosage sensitivity of amplified/deleted target genes. The results show that miRNAs can modulate oncogenic biological functions by regulating the genes within the CNA regions, and thus play a role as a trigger or balancer in cancer, affecting cancer processes, even survival. This work provided a framework for analyzing the regulation of dosage effect, which will shed a light on understanding the oncogenic and tumor suppressive mechanisms of CNA. Besides, new cancer-related miRNAs were identified. [ABSTRACT FROM AUTHOR]