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The theory of “Extension of Intuitive Knowledge”, “Mind is Principle” and “Unity of Knowledge and Action” in Wang Yangming’s thought integrates philosophy, literature, education, morality, etc., which can not only be traced back to the philosophical level, but can also be embodied in educational thought. Based on Wang Yangming’s philosophical thought, the educational thought has internalized the “heavenly principle” of external authority into the human heart, and turned it into the “conscience” of people’s inner self-consciousness. It embodies the humanistic awareness and humanistic care that is different from “Keeping the Justice, Eliminating the Desire”, and has a unique era value for the shaping of the Chinese ideological and cultural system and the creative transformation of traditional educational ideas.

In estuarine sediment, the nitrite oxidation process mediated by bacteria is significant in the nitrification process. Nitrospira is the most widely distributed in diverse group of nitrite-oxidizing bacteria (NOB), and can adapt to various environment. In this study, the Nitrospira-specific primer nxrB 169F-638R was used to analyze the microbial communities in the sediments of low-, middle-, and high-level zones of the Luan River estuary. The structure of microbial community and its response to environmental factors were discussed. The abundance and diversity of Nitrospira were the highest in the low-level zone and the lowest in the high-level zone. Lineage II (43.58%) and lineage IV (32.09%) were the dominant Nitrospira. It was found that the distribution pattern of Nitrospira was also affected by complex environmental factors such as the concentration of NH4+, Fe and Cu cations. Therefore, this study is helpful in understanding the niche differentiation and adaptation strategies of Nitrospira in an estuarine sediment environment and in providing references for single-step nitrification.

In rhizospheric soil, arsenic can be activated by both biological and abiotic reactions with plant exudates or phosphates, but little is known about the relative contributions of these two pathways. The effects of microorganisms, low-molecular-weight organic acid salts (LMWOASs), and phosphates on the migration of As in unrestored and nano zero-valent iron (nZVI)-restored soil were studied in batch experiments. The results show that As released by microbial action accounted for 17.73%, 7.04%, 92.40%, 92.55%, and 96.68% of the total As released in unrestored soil with citrate, phytate, malate, lactate, and acetate, respectively. It was only suppressed in unrestored soil with oxalate. In restored soil, As was still released in the presence of oxalate, citrate, and phytate, but the magnitude of As release was inhibited by microorganisms. The application of excess nZVI can completely inhibited As release processes induced by phosphate in the presence of microorganisms. Microbial iron reduction is a possible mechanism of arsenic release induced by microorganisms. Microorganisms and most environmental factors promoted As release in unrestored soil, but the phenomenon was suppressed in restored soil. This study helps to provide an effective strategy for reducing the secondary release of As from soils due to replanting after restoration.

Silver clusters usually have intriguing aesthetic structures and multiple application prospects in optical materials, chemocatalysis, bioimaging and chemosensors. However, these practical applications usually suffer from the instability of silver clusters. How to transform this disadvantage into an advantage for meaningful applications of silver clusters remains challenging. In this work, we judiciously prepared a silver cluster of Ag24 using an aggregation-induced emission (AIE) ligand. Due to the argyrophilia of sulfur, Ag24 can be easily destroyed by sulfur-containing pesticides such as ethion, releasing the AIE fragments. As a result, a “turn-on” emission change was observed, making Ag24 a potential chemosensor for detecting ethion in water dominated solutions. This work provides new thoughts for the design of silver cluster-based luminescent chemosensors, and broadens the application range of silver clusters.

The ability to control the risk of soil heavy metal pollution is limited by the inability to accurately depict their spatial distributions and to reasonably delineate the risk zones. To overcome this limitation and develop machine learning methods, a hybrid data-driven method supported by random forest (RF) and fuzzy c-means with the aid of inverse distance weighted interpolation was proposed to delineate and further identify risk zones of soil heavy metal pollution on the basis of 577 soil samples and 12 environmental covariates. The results indicated that, compared to multiple linear regression, RF had a better prediction performance for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, with the corresponding R

The Central Plains Urban Agglomeration is an important growth pole of China's economy, but the rapid economic growth is accompanied by serious air pollution problems. In this paper, the latest available PM2.5 monitoring data in 2015-2017 and exposure-response relationship model are used to quantitatively analyze the health effect damages due to PM2.5 pollution. The way of disease cost, adjusted human capital, and willingness to pay were adopted to estimate the economic loss of health effect damages. The results show that health effect damages of PM2.5 pollution in 2015-2017 were 11.9251 million, 11.4292 million, and 11.1012 million, respectively, accounting for 7.41%, 7.05%, and 6.94% of the total population of this area. The health effect economic loss was 97.398 billion RMB, 93.516 billion RMB, and 94.485 billion RMB, accounting for 1.73%, 1.53%, and 1.41% of the GDP. Chronic bronchitis and premature death due to PM2.5 are the main sources of health effect economic loss. Elderly people and infants are vulnerable groups of PM2.5 pollution. Affected by economic growth level, population density, and economic structure, Heze, Zhengzhou, Handan, and Liaocheng were greatly affected by PM2.5 pollution, and their health effect damages was larger. The health effect damages and health effect economic loss due to PM2.5 pollution in this area show a downward trend, indicating that air pollution reduction measures have played a positive role. However, the whole effect is still large. According to the results, this paper puts forward the policies.

The synthesis of large nano-sized cluster-molecules is a goal that synthesists and structural scientists have been pursuing, as well as a huge challenge. Herein, the largest 3d-4f metal clusters Cl12@Gd158Co38 and Br12@Gd158Co38 until now are obtained through the “multi-anions-template” strategy, with a protein-sized metal frame (ca. 4.3 × 3.6 × 3.5 nm3). Different from the mixed distribution of 3d and 4f metals and the hollow structure in the previous giant 3d-4f clusters, for the dense core-shell structure Cl12@Gd158Co38 and Br12@Gd158Co38, the Ln158 core with the highest Ln nuclearity number is induced by icosahedra-shaped templates [Cl12]12- or [Br12]12-, while 3d metals (Co) are distributed on its periphery. Their appearances point out a new structure type of non-open giant Ln-based clusters (metal number > 100) and provide an ideal model for studying the multi-level assembly of complex macromolecules. Additionally, Cl12@Gd158Co38 shows the largest magnetic entropy change (-∆Smmax = 46.95 J kg-1 K-1 under 2.0 K and ΔH = 7 T) among reported high-nuclearity 3d-4f clusters.

Songnen plain is an important commodity grain base of China, and this is the first study on the comprehensive detection of multiple pesticides in groundwater. Based on an analytical method of 56 pesticides, 30 groundwater samples were collected and analyzed. At least 4 pesticides were detected in each sample and 32 out of 56 pesticides were detected. The average detected levels of individual pesticides were approximately 10-100 ng/L. Organophosphorus pesticides and carbamate pesticides were the dominant pesticides, and their percentage of total pesticide concentrations were 35.9% and 55.5%, respectively. Based on the spatial distribution, the characteristic of nonpoint source pollution was indicated in the whole study area except for a point source pollution with the influence of a sewage oxidation pond. Nine core pesticides and three distinct clusters of the core pesticides with various concentration patterns were revealed by cluster analysis. Linear regression identified a significant relationship between the cumulative detections and the cumulative concentrations, providing access to identify the outlying contaminant events that deviate substantially from the linear trend. A new insight for prediction of pesticide occurrence was provided by the Pearson correlation between some individual pesticide concentrations and the cumulative detections or the cumulative concentrations. According to health risk assessment, the residual pesticides posed medium risks for children and infants and approximately 90% of risks were composed of β-HCH, dimethoate, ethyl-p-nitrophenyl phenylphosphonothioate and methyl parathion. These findings contributed to establishing a database for future monitoring and control of pesticides in agricultural areas.

Very little is known about bio-oxidation tailings as an arsenic (As) pollution source. A comparison study was carried out between three flotation tailings (N1-1, N1-2 and N1-3) and three bio-oxidation tailings (N2-1, N2-2 and N2-3), collected from the Yangshu gold mine in China. A combined approach of mineralogy, geochemistry and environmental geochemistry was applied to explore geochemical and mineralogical properties, As fractions and its release behavior of the bio-oxidation tailings. The results showed that extremely high total As (TAs) of 25,200–27,100 μg/g (air-dry weight) observed in N2-1, N2-2 and N2-3 was about 30 times higher than that (616–940 μg/g) in N1-1, N1-2 and N1-3. The main elements were As, Ca, Fe and S, the mineral phases were gypsum (CaSO4) (accounting for >95 wt%), and the corresponding As was present as FeAsS and As2O5 in N2-1, N2-2 and N2-3. A larger amount of As in the water-soluble (5.80–9.98 μg/g), exchangeable (9.42–15.70 μg/g), carbonate-bound (29.23–63.36 μg/g) and Fe/Mn oxide-bound (5825–12,218 μg/g) fractions was found in N2-1, N2-2 and N2-3. Solution TAs released from N2-2 was higher than the level released from N1-1, and predominantly present in the oxidised form as arsenate As(V) in 192 h. The bio-oxidation tailings are able to release more As, and are a potential As pollution source of soil, surface and ground water.

Once, the fast-growing economy has dependence on resources and environment, especially in Central Plains Urban Agglomeration (CPUA). Assessing the relationship between economic growth and resources and environment can be helpful in planning future region development. As there were fewer researches on the decoupling analysis in CPUA, therefore, according to the decoupling index designed by Tapio, this paper connected the resources and the environment to describe the comprehensive decoupling state of economic growth and resources environment as a whole with the latest available data in 2004-2015. The results showed that: (1) The change of environmental decoupling index had a greater impact on the comprehensive decoupling index. Economic growth has been less dependent on resources consumption and environment pollution since 2011, and the relationship between economic growth and resources environment reached strong decoupling in 2015. (2) The decoupling state was towards the direction of strong decoupling in Luoyang, Pingdingshan, Jiaozuo, Xuchang, Nanyang, and Xinyang. The economic growth was less dependent on resources consumption and the environment pollution. (3) Economic growth depended strongly on resources consumption and environment pollution in Changzhi, Jincheng, Heze, and Anyang. They had not yet achieved the strong decoupling state among economic growth, resources and the environment. Thus, the policy implementations were put forward to realize strong decoupling in CPUA.

A series of novel 3D 3d-4f heterometallic cluster-based coordination polymers, [Ln

Background Patients with primary hyperparathyroidism (PHPT) may be asymptomatic, and some may present with normocalcemic PHPT (NPHPT). Patients with vitamin D deficiency may also be asymptomatic, with normal calcium and elevated PTH concentrations. These latter patients are usually diagnosed with vitamin D deficiency-induced secondary hyperparathyroidism (VD-SHPT). Therefore, it is very difficult to distinguish PHPT and NPHPT from VD-SHPT based on calcium or PTH concentrations in clinical settings. In this case-control study, we aimed to verify the diagnostic power of a new parathyroid function index (PFindex = Ca*PTH/P). Methods This study enrolled 128 patients with surgically and pathologically confirmed PHPT, including 36 with NPHPT, at a hospital in West China between January 2009 and September 2017. Thirty-seven patients with VD-SHPT and 45 healthy controls were selected from the population of a cross-sectional epidemiological study as the SHPT and healthy groups, respectively. We used the PFindex to describe the characteristics of PHPT, NPHPT, and VD-SHPT.. Differences between the four groups were compared, and a receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic power of PFindex. Results The PHPT group had the highest PFindex (454 ± 430), compared to the other three groups (NPHPT: 101 ± 111; SHPT: 21.7 ± 6.38; healthy: 12.2 ± 2.98, all p 34 to differentiate NPHPT from VD-SHPT yielded the highest positive likelihood ratio and lowest negative likelihood ratio. Conclusion The PFindex provided excellent diagnostic power for the differentiation of NPHPT from VD-SHPT. This simple tool may be useful for guiding timely decision-making processes regarding the initiation of vitamin D treatment or surgery for PHPT.

Single crystal of iridium with two different orientations, [100] and [110] has been successfully prepared by electron-beam floating zone melting (EBFZM). The experimental results showed that the iridium single crystal with [100] orientation could be directly prepared without seeding at a low growth rate below 3 mm/min, and the single crystal with [110] orientation could be only obtained by seeding. The competitive growth of the bicrystal demonstrated that the [100] orientation of the iridium single crystal can overwhelm that of the [110] orientation at a growth rate of 2 mm/min. Moreover, the interface growth undercooling including curvature undercooling and kinetic undercooling has been calculated for iridium single crystal with these two orientations. The calculated data and analysis agree well with the experimental results.

The Central Plains Urban Agglomeration is an important growth pole of China's economy, but the rapid economic growth is accompanied by serious air pollution problems. In this paper, the latest available PM

Cold rolling combining subsequent annealing is implemented to tune the microstructure and mechanical properties of Al0.5CoCrFeNi high-entropy alloy. Results show that the microstructure of Al0.5CoCrFeNi HEA after 80% thickness reduction is severely deformed along the rolling direction. Prominent work hardening effect on Al0.5CoCrFeNi HEAs is evidenced by the remarkable enhancement of the hardness and strength at the sacrifice of ductility. After annealing, detailed description of microstructure evolution, texture analyses as well as tensile properties are given. Strongly temperature dependent recrystallized microstructure manifests the rather high recrystallization temperature (0.81 Tm) that can be attributed to original coarse as-cast grains, severe lattice distortion effect and sluggish diffusion effect. Progressively smaller intensity of deformed texture proves the function to eliminate texture effectively of recrystallization in spite of the detection of weak recrystallization texture. Tensile tests of annealed Al0.5CoCrFeNi HEAs show the strength decreases dramatically while ductility increases remarkably accompanying increased annealing temperature. To sum up, cold rolling combining subsequent annealing is a valid method to gain grain refined Al0.5CoCrFeNi HEAs with adjustable properties that are prospective for many kinds of application.

Freshwater contaminants tend to precipitate into intertidal surface sediments, particularly in the estuary and intertidal zones during freshwater–seawater mixing. Quinolone-type antibiotics are such contaminants, and their concentrations in the intertidal sediments are important indicators for the whole spectrum of antibiotics used in the estuary and adjacent areas. The impacts of sediment types and environmental factors on the distribution of 16 quinolones were probed based on nine Bohai and 42 Yellow Sea intertidal sediment samples. The samples were collected from locations along the coastal areas in China. Quinolones were detected in all samples, while moxifloxacin, ciprofloxacin, and ofloxacin were detected at a frequency >50%. Sediment types, pH, organic carbon content, K, Na and Fe concentrations had little correlation with quinolone distributions in intertidal sediments. However, combined concentrations of Ca + Mg (46.7 g/kg in Bohai and 13.7 g/kg in Yellow Sea samples) appeared to correlate with oxolinic acid detecting frequencies (88.9% and 4.8%, respectively) and concentrations (2.0–10.1 μg/g and up to 3.09 μg/g, respectively). Different detection frequencies of the quinolones could be attributed to the formation of cation bridges between oxolinic acid and Ca + Mg, which results in dominant sorption of oxolinic acid at different locations and sediment matrices.

Both numerical and experimental approaches were conducted to investigate the electron beam floating zone melting (EBFZM) of iridium crystal. A finite element model was established and the temperature fields under different processing parameters were calculated and discussed. The heating power, the rod diameter and the movement of heating source significantly influence the temperature distribution in the iridium rod. Once the heating starts, the temperature quickly increases and gradually reaches the steady state. The melting zone enlarges with the increase of heating power, and the critical power for obtaining a complete melting zone is 5.5 kW ∼ 6.0 kW in 20 mm-diameter Iridium rod. With the upward movement of heating source, the melting zone obviously enlarges and the lower solid/liquid (S/L) interface becomes more planar. Then how to get a complete melting zone with a suitable volume and the control of a planar S/L interface were discussed. An optimized processing window was proposed and applied to the EBFZM of iridium crystal. An iridium rod 20 mm in diameter was successfully produced and the microstructural morphologies indicated that the initial polycrystalline microstructure will evolve into single crystal.

Gold tailings often release arsenic (As) contaminants into the surrounding environment. Microorganisms play an important role in the As cycle, whereas the effects of As on bacterial communities remain unclear. To reveal the effects of As on the diversity of bacterial communities and their As-tolerance potential, farmland soil and river sediment samples were collected at various distances from tailings in the Dandong area of northeastern China. The bacterial communities were analyzed using high-throughput sequencing of 16S rRNA genes. The membrane transport proteins ArsB and (or) ACR3 pump As(III) out of the cell to resist As toxicity. We studied the abundance and phylogeny of ArsB and ACR3 using PCR-based clone libraries and quantitative PCR. The bacterial community was divided into 10 phyla and 59 genera. The transformation from As(V) to As(III) was predominant, which was coupled with denitrification. Both ArsB and ACR3 likely evolved from different orders of Proteobacteria. The arsB gene seems to be more stable in bestowing bacteria with the capability to respond to the As concentration. Moreover, As with iron, manganese, and total organic carbon also influenced the clustering relationships of samples and bacterial distribution.

Freshwater mental contaminants which in the estuary tend to precipitate into intertidal surface sediments during freshwater-seawater mixing because of heavy water chemical reaction. The impacts of ferric hydroxide on the removal rate of Cr with increasing pH and salinity were conducted by laboratory simulation experiment. The removal rate of Cr by ferric hydroxide decreased with increasing pH from river water to seawater in the estuary; this is because pH changed the Zeta potential of ferric hydroxide. And with increasing salinity, the removal rate of Cr by ferric hydroxide firstly decreased and then increased. On the hand, Na+ entering the sliding surface, which could improve Zeta potential and stability of ferric hydroxide colloid, which leads to the amount of Cr removal by colloid aggregation decreased. On the other hand, there was competitive adsorption between Cland CrO42-/HCrO4-. In this study, Fe was the key factor of heavy metal Cr distribution with pH change.

The urbanization process has some impacts on air quality. And PM2.5 is considered as the critical air pollutant. "2 + 26" Cities, the air pollution transmission channel cities of Jing-Jin-Ji, has been serious air pollution in recent years. Previous studies on "2 + 26" Cities urbanization process were few, and there were also few studies on the effects of different urbanization levels on PM2.5 pollution. Thus, the paper took "2 + 26" Cities as an example to assess the impacts of urbanization process and different urbanization levels on PM2.5 pollution. The panel data of population, economic and land aspects from 1999 to 2016 and fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) methods were utilized. It was found that there was significant positive relationship between urbanization process and PM2.5. The influential mechanisms of urbanization process on PM2.5 pollution varied with the cities’ developing levels. Therefore, the governments should take urban development levels into consideration to formulate appropriate PM2.5 concentrations control policies.

A series of lanthanide compounds, [Ln

A modified montmorillonite (MMT) was prepared using an acid activation-sodium activation-iron oxide coating method to improve the adsorption capacities of natural MMTs. For MMT, its interlamellar distance increased from 12.29 to 13.36 Å, and goethite (α-FeOOH) was intercalated into its clay layers. Two novel media-injected permeable reactive barrier (MI-PRB) configurations were proposed for removing arsenic from groundwater. Sand tank experiments were conducted to investigate the performance of the two MI-PRBs: Tank A was filled with quartz sand. Tank B was packed with quartz sand and zero-valent iron (ZVI) in series, and the MMT slurry was respectively injected into them to form reactive zones. The results showed that for tank A, total arsenic (TA) removal of 98.57% was attained within the first 60 mm and subsequently descended slowly to 88.84% at the outlet. For tank B, a similar spatial variation trend was observed in the quartz sand layer, and subsequently, TA removal increased to ≥99.80% in the ZVI layer. TA removal by MMT mainly depended on both surface adsorption and electrostatic adhesion. TA removal by ZVI mainly relied on coagulation/precipitation and adsorption during the iron corrosion. The two MI-PRBs are feasible alternatives for in situ remediation of groundwater with elevated As levels.

An ion chromatography method was developed for the simultaneous detection of three soluble herbicides (glyphosate, bentazone and picloram), three chlorine disinfection byproducts (monochloroacetic acid, dichloroacetic acid and trichloroacetic acid) and 12 anions in water (Cl(-), Br(-), SO4(2-), CO3(2-), ClO3(-), ClO4(-), BrO3(-), PO4(3-), NO2(-), NO3(-), CH3COO(-) and COO(-)). High linearity (r(2) > 0.996) was observed for all target analytes for each respective concentration range. The limit of detection and limit of quantitation were between 0.21-0.85 and 0.06-25.46 μg/L, respectively. However, the interference effect of Cl(-), NO3(-) , SO4 (2-) and CO3(2-) on some target analytes must be considered during the analysis. Sample pre-treatment by a hydrogen column (H-column) required to reduce the negative effect of CO3(2-). Additionally, sample pre-treatment by a sliver-hydrogen column (Ag-H-column) is required when Cl(-) > 100 mg/L and SO4(2-) 100 mg/L and SO4(2-) > 50 mg/L. When Cl(-) > 100 mg/L, SO4(2-) > 50 mg/L and CO3(2-) > 20 mg/L, the sample pre-treatment by either an Ag-H-Ba-column or an Ag-H-column and Ba-column is required to minimize interference.

Benzoic acid can affect the iron-oxide mineral dissolution and react with hydroxyl radical. This study investigated its effect on 1,2-dichloroethane removal process by siderite-catalyzed hydrogen peroxide and persulfate. The variation of benzoic acid concentrations can affect pH value and soluble iron concentrations; when benzoic acid varied from 0 to 0.5 mmol/L, pH increased while Fe(2+) and Fe(3+) concentrations decreased, resulting in 1,2-dichloroethane removal efficiency which decreased from 91.2 to 5.0%. However, when benzoic acid varied from 0.5 to 10 mmol/L, pH decreased while Fe(2+) and Fe(3+) concentrations increased, resulting in 1,2-dichloroethane removal efficiency which increased from 5.0 to 83.4%.

A series of WO 3 /TiO 2 composite photocatalysts were fabricated via a facile salt–ultrasonic assisted hydrothermal process. The obtained samples were characterized by X-ray diffraction, scanning eletron microscopy, energy dispersive X-ray spectroscopy and UV–vis diffused reflectance spectroscopy. It was confirmed that anatase TiO 2 and monoclinic WO 3 coexisted in the composites. The photocatalytic activity of as-prepared WO 3 /TiO 2 composites for degradation of Rhodamin B (RhB) under visible light irradiation was investigated. The results showed that WO 3 /TiO 2 composites have a higher photocatalytic activity than those of pure TiO 2 and pure WO 3 . First-principle calculations based on density functional theory were performed to explore the electronic structure and illustrate the photocatalytic mechanism of WO 3 /TiO 2 . The calculated energy gap was 2.53 eV, which was close to the experimental observation (2.58 eV). Due to the combination of WO 3 /TiO 2 , the photoinduced electrons and holes transfer between the WO 3 and TiO 2 in opposite directions, thus providing sufficient charge separation, which contributed to the photocatalytic activity enhancement.

A sediment core collected from coastal zone near the Qiao Island in the Pearl River Estuary was analyzed for total metal concentrations, chemical partitioning, and physico-chemical properties. Three vertical distribution patterns of the heavy metals in the sediment core were identified, respectively. The dominant binding phases for Cu, Pb, Cr, and Zn were the residual and Fe/Mn oxides fractions. Cd in all sediments was mainly associated with exchangeable fraction. Influences of total organic carbon content and cation exchange capacity on the total concentrations and fractions of almost all the metals were not evident, whereas sand content might play an important role in the distributions of residual phases of Cr, Cu, Pb, and Zn. In addition, sediment pH had also an important influence on the Fe/Mn oxides, organic/sulfide and residual fractions of Cr, Cu, and Zn. Contamination assessment on the heavy metals in the sediment core adopting Index of Geoaccumulation showed that Cr, V, Be, Se, Sn, and Tl were unpolluted, while Cu, Ni, Pb, Zn, Cd, and Co were polluted in different degrees throughout the core. It was remarkable that the various pollution levels of the metals from moderate (for Cu, Pb, and Zn) to strong (for Cd) were observed in the top 45 cm of the profiles. The relative decrease of the residual fraction in the upper 45 cm of the core is striking, especially for Zn and Cu, and, also for Pb, and Cr. The change in fraction distribution in the upper 45 cm, which is very much contrasting to the one at larger depths, confirms that the residual fraction is related to the natural origin of these metals, whereas in the upper part, the non-residual fractions (mainly the Fe/Mn oxides fraction) are increased due to pollution in the last decade. The possible sources for Cu, Pb, Zn, and Cd contaminations were attributed to the increasing municipal and industrial wastewater discharges, agricultural runoff, atmospheric inputs, and runoff from upstream mining or smelting activities, which may be associated with an accelerating growth of economy in the Pearl River Delta region in the past decade.

Abiotic stresses such as drought and extremes of temperature commonly reduce both yield and quality of potato. This study investigated the potential to use gene transfer technology to enhance the tolerance of potato to commonly encountered abiotic stresses. Agrobacterium mediated transformation was used to create lines of potato (cv. Desiree) that over-expressed either a wheat mitochondrial Mn superoxide dismutase (SOD3:1), dehydrin 4 (DHN 4) isolated from barley, a cold-inducible transcriptional factor DREB/CBF1 isolated from canola or ROB5, a stress inducible gene isolated from bromegrass that encodes for a heat stable LEA group 3-like protein. The transgenes were under the control of either a constitutive 35S promoter or a stress-induced Arabidopsis COR78 promoter. Yield potential of the transformed lines was evaluated under drought stress conditions in a greenhouse trial and under non-irrigated conditions in field trials conducted over 4 years in Saskatoon, Saskatchewan. In the years when the field trials experienced significant drought stress (2001, 2003 and 2006) many of the transformed lines produced higher yields than the control. However, under relatively cooler, wetter conditions (2005 cropping season) yields of most transformed lines were equivalent or inferior to the non-transformed parental line. Under non-stressed conditions, transformations utilizing the stress-induced COR78 promoter were higher yielding than transformations based on the constitutive 35S promoter. Combining the ROB5, DHN or SOD3.1 transgenes with the COR78 promoter all showed significant potential to enhance yields under moisture stress. All of the transgenes appeared to enhance the heat stress tolerance (44°C) of whole plants or excised leaves, with lines transformed with SOD3.1 showing the greatest effect. In low temperature stress trials conducted under controlled environment conditions and in the field, lines over-expressing SOD3:1 showed an enhanced capacity to grow at sub-optimal temperatures (10°C), while lines transformed with SOD3.1 or ROB5 had greater tolerance of freezing temperatures than the parental line. These results are encouraging as even a small degree of enhancement of stress tolerance has the potential to produce significant economic benefits in high value/stress sensitive crops such as potato.

Deformation textures and recrystallization textures of ultrafine grains pure copper produced by asymmetrical accumulative roll-bonding (AARB) and symmetrical accumulative roll-bonding (ARB) respectively were investigated using X-ray diffraction (XRD). It was found that dominant deformation textures of copper after 98.4% strain are {1 0 0} shear texture by AARB and {2 1 1} copper texture by ARB, a mixed “deformation–recrystallization” texture is observed during the first stage of recrystallization, dominant recrystallization texture is {0 0 1} cube texture in samples produced respectively by AARB and ARB. We suggest that deformation textures and recrystallization textures are controlled by the crystal structures and deformation methods of samples, some unusual properties in ultrafine grains pure copper are possibly unstable.

A method was developed for the determination of clenbuterol in porcine meat by iso- topic dilution mass spectrometry (IDMS). National Institute of Metrology of China (NIM) par- ticipated in the international comparison activity organized by Asia Pacific Metrology (APMP) and got an international mutual recognition result using this method. The important factors of the method, such as the spray voltage, mobile phase, chromatographic column, extraction, purification and filtration conditions were investigated to acquire optimum conditions. The opti- mization results showed that the composition and pH value of the mobile phase had effects on the response of the mass spectrum of clenbuterol and the optimal value of the spray voltage. The solvent of sample had influences on the chromatographic retention behavior of clenbuterol. It was found that methanol caused a serious solvent effect, even made chromatographic peak split. Since clenbuterol was easily adsorbed on hydrophilic filter membranes and solid phase extraction columns, there were interference suppressions for the quantification of clenbuterol because of the eluate of the solid phase extraction columns. The homogenate method with extraction solvent of 0.1% (v/v) formic acid in acetonitrile had the highest extraction efficiency. The limit of the detection (LOD, S/N > 3) of the method was 0.2 μg/kg. The determination results of clenbuterol in the porcine meat by this method were 5.18 μg/kg ± 0.50 μg/kg (k = 2). This method is accurate, reliable, reproducible, and suitable for the determination of clenbuterol with trace quantity in porcine meat.

An ion chromatography method was developed for the simultaneous detection of three soluble herbicides (glyphosate, bentazone and picloram), three chlorine disinfection byproducts (monochloroacetic acid, dichloroacetic acid and trichloroacetic acid) and 12 anions in water (Cl(-), Br(-), SO4(2-), CO3(2-), ClO3(-), ClO4(-), BrO3(-), PO4(3-), NO2(-), NO3(-), CH3COO(-) and COO(-)). High linearity (r(2)0.996) was observed for all target analytes for each respective concentration range. The limit of detection and limit of quantitation were between 0.21-0.85 and 0.06-25.46 μg/L, respectively. However, the interference effect of Cl(-), NO3(-) , SO4 (2-) and CO3(2-) on some target analytes must be considered during the analysis. Sample pre-treatment by a hydrogen column (H-column) required to reduce the negative effect of CO3(2-). Additionally, sample pre-treatment by a sliver-hydrogen column (Ag-H-column) is required when Cl(-)100 mg/L and SO4(2-)50 mg/L, and pre-treatment by both a barium column (Ba-column) and an H-column is required when Cl(-)100 mg/L and SO4(2-)50 mg/L. When Cl(-)100 mg/L, SO4(2-)50 mg/L and CO3(2-)20 mg/L, the sample pre-treatment by either an Ag-H-Ba-column or an Ag-H-column and Ba-column is required to minimize interference.

Background As the largest low-latitude permafrost region, the Tibetan Plateau (TP) is an important part of the earth’s terrestrial ecosystem and one of the most vulnerable areas to climate change and human activities. However, to the best of our knowledge, the bacterial communities in TP soils and their roles in biogeochemical cycles remain limited. Results In this study, we report the bacterial community structure and function as well as their correlation with environmental factors in TP major ecosystems (farmland, alpine meadow and oligosaline lake) by using metagenomic approaches. Compared with other soil samples in various environments, TP soils share a core set of microorganisms with a distinct abundance and composition. Among TP soil samples, the taxonomic and functional composition of bacterial communities among the upper (3-5 cm) and lower (18-20 cm) soils of farmland sites were highly similar, whereas the dissimilarities within alpine meadow samples were significantly greater than among farmland samples. A similar pattern was observed in elements cycles and pathways associated with adaption to environment and land use types. Canonical correlation analysis revealed that the bacterial communities in most of farmland and alpine meadow soil samples were also significantly correlated with geogenic variables. Specifically, the root-nodule bacteria are negatively correlated with the soil moisture and pH, while Thiobacillus associated with sulfur cycles show potential responses to low temperature and intense UV radiation. Conclusions These findings indicate that the bacterial community structure and functions in TP soils were influenced by both human activities and soil environmental properties, and that the bacterial communities appeared to be more homogenized in the farmland soils compared with pristine alpine meadows.

Several Daucus carota (carrot) and Nicotiana tabacum (tobacco) cell lines that had been selected as resistant to Pro, Trp, Lys and Met analogs were thawed after over 10 years of cryostorage in liquid nitrogen. Some of these cell lines had been cloned. Viable cells were recovered in all cases, and growing lines were recovered from the carrot lines when placed either on feeder plates or directly into liquid medium. Some tobacco cultures were recovered only in liquid medium, but two Trp analog-resistant cloned lines could not be recovered after several attempts. Generally the cryopreserved lines retained the original resistance and corresponding free amino acid levels while the same lines maintained as callus with monthly transfers for the same period often lost the resistance. Our study shows that carrot and some, but not all, tobacco cultured cell lines can be cryopreserved for over 10 years and still be recovered with their original characteristics.

The photosynthetic cell suspension culture of soybean [Glycine max (L.) Merr. cv. Corsoy] (SB-M) was successfully cryopreserved in liquid nitrogen using a preculture and controlled freezing to −40° C (two-step) freezing method. The effective method included a preculture treatment with gradually increasing levels of sorbitol added to the 3% sucrose already present in the medium. The cells were then placed in a cryoprotectant solution [10% DMSO (dimethylsulfoxide) and 9.1% sorbitol, or 10% DMSO and 8% sucrose], incubated for 30 min at 0° C, cooled at a rate of 1° C/min to −40° C, held at −40° C for 1 h, and then immersed directly into liquid nitrogen. The cells were thawed at 40° C and then immediately placed in liquid culture medium. The cell viabilities immediately after thawing were 75% or higher in all cases where cell growth resumed. The original growth rate and chlorophyll level of the cells was recovered within 40 to 47 d. If the sorbitol level was not high enough or the preculture period too short, growing cultures could not be recovered. Likewise, survival was not attained with cryoprotectant mixtures consisting of 15% DMSO, 15% glycerol, and 9.1% sucrose or 15% glycerol and 8% sucrose. The successful method was reproducible, thus allowing long-term storage of this and certain other unique photosynthetic suspension cultures in liquid nitrogen.

With rapid urbanization, anthropogenic activities are increasingly influencing the natural environment of the Bohai Bay. In this study, the composition and variation of bacterial and nirS-harboring bacterial communities in the coastal zone sediments of the Bohai Gulf were analyzed using PCR-based clone libraries. A total of 95 genera were detected in the bacterial communities, with Proteobacteria (72.1 %), Acidobacteria (10.5 %), Firmicutes (1.7 %), Bacteroidetes (1.4 %), Chloroflexi (0.7 %) and Planctomycetes (0.7 %) being the dominated phyla. The NirS sequences were divided into nine Clusters (A–I). Canonical correlation analysis showed that the bacterial or denitrifying communities were correlated with different environmental factors, such as total organic carbon, total nitrogen, ammonium, sulfate, etc. Furthermore, bacterial communities’ composition and diversity are influenced by oil exploration, sewage discharge and other anthropogenic activities in the coastal area of the Bohai Sea. Thus, this study provided useful information on further research on regional or global environmental control and restore.

Seven suspension-cultured lines of five different species (Amaranthus powellii Datura innoxia, Glycine max, Gossypium hirsutum, andNicotiana tabacum × Nicotiana glutinosa fusion hybrid), which had been grown under photomixotrophic conditions, were placed under heterotrophic conditions (darkness and media with 3% sucrose or starch) where the chlorophyll levels declined to near zero. After three transfers over a 70-d period, the cells were placed back into photomixotrophic or photoautotrophic conditions where regreening occurred rapidly and continued growth was observed. This rapid adaptation to photosynthetic conditions contrasts with the original initiation process for these cultures, which required many months and an apparent selection since many of the original cells died. Thus, these seven photosynthetic cell suspension cultures appear to be different from the original cultures due possible to genetic or adaptive changes.

It is generally acknowledged abiotic stress tolerance is induced in response to an environmental stimulus resulting in the upregulation of multiple stress genes. Stimulus perception governs the extent of upregulation of stress associated proteins. This upregulation dictates when a plant initiates acclimation and thus the extent of stress tolerance the plant acquires. Often cultivated crops do not perceive an environmental stress, such as an episodic frost, early enough to acclimate. As a result, cultivated crops are often lethally injured by an unseasonal -3 to -4 °C frost whereas if given sufficient time they can acclimate to withstand much lower temperatures (e.g. -9 to -12 °C). Drought tolerance is generally induced as a consequence of plants experiencing a wet-dry cycle. During the day, plants lose turgor due to a water shortage; however, during the night plants regain turgor due to the reduced evapo-transpiration rate. As a result of the cycle, drought associated genes are upregulated. In many cool season crops, leaf temperatures exceeding 30 °C induce the formation of heat shock proteins that protect the cell. Maximum frost and drought tolerance is attained after several weeks of acclimating conditions; in contrast, enhanced heat tolerance can be attained in hours.