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Straw return is an effective management practice. It not only utilizes agricultural waste but also introduces dissolved organic matter (DOM) into the soil. Selenium (Se) is an essential trace element in the human diet and contributes to the popularity of Se-enriched agricultural products in the Chinese market. Moreover, there are still some Se-enriched agricultural products that have yet to be utilized. This study investigated whether Se addition in soil caused component changes in the DOM extracted from rape straw. DOM extracted from rape straw grown in soil with four Se levels (0, 0.1, 0.5 and 1.0 mg Se kg−1 soil) was characterized by UV-Visible spectroscopy, fluorescence spectroscopy and FTIR spectroscopy. The UV-visible spectra revealed that 0.1 mg Se kg−1 soil reduced the molecular weight of DOM and caused the presence of more irreplaceable aromatic structures in the substituent groups of the DOM, while 0.5 and 1.0 mg Se kg−1 soil only reduced the DOM molecular weight. Fluorescence spectroscopy indicated that Se improved the humification degree but reduced the aromaticity of DOM. FTIR spectra proved that Se altered the contents of carboxylic acids, amino acids, alcohols and aromatic heterocycles in DOM, which were maximized in the 0.5 and 1.0 mg Se kg−1 treatment groups. We concluded that Se application could change the composition of DOM extracted from rape straw, potentially impacting the nutrient bioavailability in soil. This study provides basic data on Se-enriched rape straw utilization for eco-agriculture.

Solution culture experiments were conducted to investigate the effect of wastewater nitrogen levels and NH

Cadmium (Cd) is highly toxic, even at very low concentrations, to both animals and plants. Pollen is extremely sensitive to heavy metal pollutants; however, less attention has been paid to the protection of this vital part under heavy metal stress. A pot experiment was designed to investigate the effect of foliar application of Se (1 mg/L) and Mo (0.3 mg/L) either alone or in combination on their absorption, translocation, and their impact on Cd uptake and its further distribution in Brassica napus, as well as the impact of these fertilizers on the pollen grains morphology, viability, and germination rate in B. napus under Cd stress. Foliar application of either Se or Mo could counteract Cd toxicity and increase the plant biomass, while combined application of Se and Mo solutions on B. napus has no significant promotional effect on plant root and stem, but reduces the seeds’ weight by 10–11%. Se and Mo have decreased the accumulated Cd in seeds by 6.8% and 9.7%, respectively. Microscopic studies, SEM, and pollen viability tests demonstrated that pollen grains could be negatively affected by Cd, thus disturbing the plant fertility. Se and Mo foliar application could reduce the toxic symptoms in pollen grains when the one or the other was sprayed alone on plants. In an in vitro pollen germination test, 500 μM Cd stress could strongly inhibit the pollen germination rate to less than 2.5%, however, when Se (10 μM) or Mo (1.0 μM) was added to the germination medium, the rate increased, reaching 66.2% and 39.4%, respectively. At the molecular level, Se and Mo could greatly affect the expression levels of some genes related to Cd uptake by roots (IRT1), Cd transport (HMA2 and HMA4), Cd sequestration in plant vacuoles (HMA3), and the final Cd distribution in plant tissue at the physiological level (PCS1).

The influence of different pretreatment methods on anaerobic mixed inoculum was evaluated for selectively enriching the hydrogen (H2) producing mixed culture using glucose as the substrate. The efficiency of H2 yield and the glucose fermentation pathway were found to be dependent on the type of pretreatment procedure adopted on the parent inoculum. The H2 yield could be increased by appropriate pretreatment methods including the use of heat, alkaline or acidic conditions. Heat pretreatment of the inoculum for 30 min at 80 °C increased the H2 yield to 53.20% more than the control. When the inoculum was heat-pretreated at 80 °C and 90 °C, the glucose degraded via ethanol (HEt) and butric acid (HBu) fermentation pathways. The degradation pathways shifted to HEt and propionate (HPr) types as the heat pretreatment temperature increased to 100 °C. When the inoculum was alkali- or acid-pretreated, the fermentation pathway shifted from glucose to a combination of the HPr and HBu types. This trend became obvious as the acidity increased. As the fermentation pathway shift from the HEt type to the HPr and HBu types, the H2 yield decreased.

Influence of different pretreatment methods applied on anaerobic mixed inoculum was evaluated for selectively enriching the hydrogen (H2) producing mixed culture using glucose as substrate. The cumulative H2 yield and H2 production rate were found to be dependent on the type of pretreatment procedure adopted on the parent inoculum. They could be increased by appropriate pretreatment methods, including use of heat, alkaline or acidic conditions. Along with the processing temperature and time of heat pretreatment and alkaline of alkali pretreatment increasing, the H2 yield increased and then declined, but it declined and then increased as the acidity of acid pretreatment increasing. Among the studied pretreatment methods, the heat pretreatment methods procedure enabled higher H2 yield and the maximum H2 production rate, then were alkali and acid pretreatment methods. When the inoculum was heat-treated at 80°C for 30 min, the highest cumulative H2 yield was obtained at 2152.0 mL, which was 53.20% higher than the control, and the maximum H2 production rate was 178.0 mL h-1, which was 122.0% higher than that of the Ctrl (138.0mL h-1).

The objective is to study whether the accumulation and utilization of plant N are controlled by Mo status in winter wheat cultivars. Mo-efficient cultivar 97003 (eff) and Mo-inefficient cultivar 97014 (ineff) were grown in severely Mo-deficient acidic soil (Tamm-reagent-extractable Mo 0.112 mg kg^(-1)) with (+Mo) and without (-Mo) the application of 0.13 mg kg^(-1) Mo. The accumulation and use efficiency of plant total N were significantly higher in +Mo than that in -Mo and in eff than that in ineff under Mo deficiency. N use efficiency was remarkably higher in maturity but it was forwarded to jointing stage after Mo supply, thus indicating that Mo supply promoted the N use efficiency besides N uptake and eff was efficient in N uptake and utilization. The overall activity of nitrate reductase (NR, EC 1.6.6.1) was significantly higher in +Mo than in -Mo and ratio of +Mo/-Mo was even to 14.8 at tillering stage for ineff. Activity of glutamine synthetase (GS, EC 6.3.1.2) was significantly lower in +Mo than in -Mo. Concentration of nitrate and glutamate were also significantly lower in +Mo than in -Mo, thus provided evidences for enhancing N use efficiency by Mo supply. Activities of NR and GS were significantly higher and concentrations of nitrate and glutamate were significantly lower in eff than ineff under Mo deficiency, thus indicated eff was more efficient in N reduction and utilization. It is therefore concluded that Mo could promote N accumulation and utilization in winter wheat which was directly related to NR and feedback regulated by GS. Higher Mo status also results in higher accumulation and utilization of plant N in eff.

Aims: Micro-ribonucleic acid (miRNA) are noncoding RNA molecules of 21 to 24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNA play essential roles in embryogenesis, cell differentiation and pathogenesis of human diseases. This study describes a comparison between the microRNA profile of human-papillomavirus-negative cervical squamous cell carcinoma patients and controls, in order to develop further understanding of the pathogenesis of cervical squamous cell carcinomas. Methods: MiRNA were isolated from tumor tissues of five human-papillomavirus-negative cervical squamous cell carcinoma patients and five healthy controls in order to perform miRNA microarray chip analysis. The chip results were then confirmed by northern blot analysis. Results: A total of 27 miRNA differentially expressed between the squamous cell carcinoma patients and the healthy controls were identified. Conclusion: This work indicates that these miRNA may be potential diagnosis biomarkers and probable factors involved in the pathogenesis of cervical squamous cell carcinomas.

A hydroponic experiment was conducted to investigate the effects of arsenic (As) stress on growth, nutrition and As uptake, and speciation in shoots and roots of winter wheat ( Triticum aestivum L.). Winter wheat has high tolerance to As. Most As is accumulated in the roots, and an As concentration of 4,421 mg/kg was observed at a solution concentration of 20 mg/L As. Arsenic concentrations in roots were approximately 40–100 times greater than those in shoots. Arsenic in winter wheat roots and shoots occurred as both As 3 + and As 5 + species, although As 3 + was the main species in winter wheat tissues. Arsenic significantly decreased the biomass of winter wheat shoots and roots and affected absorption and transport of micro- and macro-elements in winter wheat tissue. Arsenic treatment significantly increased the concentrations of total Magnesium (Mg) and calcium (Ca) in shoots and enhanced the transport of Mg and Ca from roots to shoots but decreased potassium (K), nitrogen (N), and phosphorus (P) concentrations in both shoots and roots, particularly the concentration of P. Concentrations of iron, copper, and zinc in winter wheat shoots were negatively related to As rates, with correlation coefficients ( R 2 ) of 0.93, 0.94, and 0.97, respectively.

Background and Aim: MicroRNAs (miRNAs) are non-coding RNA molecules of 21–24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation, and pathogenesis of human diseases including cancer. Methods: We analyzed the miRNA expression profiles in 10 pairs of hepatocellular carcinoma (HCC) and adjacent non-tumorous tissue (NT) from 10 non-viral hepatitis patients, using a mammalian miRNA microarray containing whole human mature and precursor miRNA sequences. Results: A total of 15 miRNAs exhibited higher expression in the HCC samples than that in the NT samples, and one miRNA demonstrated lower expression in the HCC samples than in the NT samples. A total of 18 miRNAs identified valid expression only in HCC samples, with six only in NT samples. The chip results were confirmed by Northern blot analysis. Conclusion: Our study may help clarify the molecular mechanisms involved in the pathogenesis of HCC, and miRNAs potentially serve as a novel diagnostic tool of HCC.

An off-line filtering ditch–pond system was designed and constructed to control the small point and runoff pollution at the Wuhan City Zoo, Hubei Province, China. The quantity and quality of wastewater discharge and runoff from 16 rainfall events were measured to test the effectiveness of the off-line treatment train. The results showed that the water quality was improved and high retention rates for water and pollutants were also achieved by the off-line treatment train. In the outflows, the event mean concentrations (EMCs) of TSS, COD, TN, TDN, TP and TDP were reduced by 75%, 50%, 50%, 57%, 74% and 80% compared to the inflows. In 2005, the annual inflow volume in the catchment was 6783 m 3 and the water retention rate was 80.1%. The retention rates in the annual loads of TSS, COD, TN and TP came to 86.4%, 85.5%, 83.9% and 82.9%, respectively. Therefore, the off-line filtering ditch–pond system was shown to be an effective and economical measure to control diffuse pollution. It would be worthwhile to extend the off-line treatment train to regions with limited land resources, especially in urban areas.

Pollution in urban zoos arises from diffuse and small point sources. However, its control has received little attention in past decades. Online and offline modes of ecological engineering technology were designed to control pollution from small point and diffuse sources in Wuhan City Zoo, China. Their characteristics and performances were investigated in sixteen runoff events from 2003 to 2005. The results showed that the two modes both improved runoff water quality and had high retention rates for water and pollutants. In the outflows, the event mean concentrations (EMCs) of total suspended solids (TSS), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were reduced by 88%, 59%, 46% and 71% for the online mode, and those were 77%, 42%, 50% and 66% for the offline mode. The annual retention rates of pollutant loads for the online mode were 94.9%-98.5% in the three study years; those for the offline mode were 70.5%-86.4%. Based on calculation, the online mode was able to store the runoff of 66.7 mm rainfall completely, and the offline mode could store that of 31.3 mm rainfall. In addition, the online mode can provide an effective way for rainwater utilization and good habitats for aquatic wildlives, and has an excellent aesthetics value for recreationsal pastimes. The offline mode can save land resources and may be an effective and economical measure for diffuse pollution control in urban areas.

The rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo solution cultivation at seedling stage to investigate the effects of selenite addition on the selenium (Se) absorption and distribution, root morphology and physiological characteristics of rape seedlings. The results showed that the bioaccumulation ability of Se decreased significantly with increasing the Se application rate, but the Se distribution coefficient remained around 0.9 with no significant influence. The application of 10 µmol . L-1 selenite stimulated the growth of rape seedlings through improving the root physiological characteristics and root morphology significantly, including significantly increasing the production of superoxide radical (O2∙-) rate and the activities of superoxide dismutase (SOD), peroxidase (POD) and fungal catalase (CAT) in the root system, which resulted in a reduction of the lipids peroxidation (MDA) content as much as 26.0%, consequently increasing the root activity as much as 17.4%. The promoting degrees of selenite on root morphological parameters were from strong to weak in such a tendency: root volumetotal surface areanumber of root forkstotal root lengthnumber of root tipsaverage diameter. However, such positive effects had no significant difference with those in treatment with 1 µmol . L-1 selenite, indicating that small amounts (≤ 10 Lmol . L-1) of selenite were able to increase the activity of antioxidant enzymes and reduce the content of MDA in root system, which could increase root activity and improve root morphology, hence increased the biomass of rape seedlings.

The objective was to probe the site where the biosynthesis of chlorophyll was blocked under Mo deficiency at low temperature, which led to the decrease of chlorophyll in winter wheat cultivars. The intermediates of chlorophyll biosynthesis were analyzed in winter wheat cultivars in soil culture, miniblock culture, and solution culture to study the effects of Mo on chlorophyll biosynthesis without Mo addition (CK, soil available Mo 0.112 mg kg−1) and Mo addition (+ Mo, 0.13 mg kg−1 Mo was added). Laevulinic acid (LA), the competitive analog of δ-aminolaevulinic acid (ALA) was also introduced in the experiment. The ratio of Chl a/Chl b was constant between CK and + Mo treatment, whereas it increased at low temperature, which indicated that Mo deficiency did not inhibit the transformation of Chl a to Chl b at low temperature. Under Mo deficiency, the contents of protochlorophyll (Pchl), Mg-protoporphyrin IX (Mg-Proto IX), protoporphyrin IX (proto IX), and uroporphyrinogen III (Uro III) decreased [Uro III decreased significantly (P

The high-quality, high-yield rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo seedling stage soil cultivation and solution cultivation. This study was aimed to investigate the effects of sulfur (S) on the fraction and species of amend selenium (Se) in soil by applying S fertilizer, and to reveal the mechanism through which S controls the Se uptake of rape. The results showed that applications of both Se at 5 mg.kg-1 and S at 150 mg.kg-1 could provide some boost to rape growth, however such boost was unremarkable; S application could significantly reduce Se content in shoots and roots by as much as 64. 0% and 39. 1% , respectively; S application could significantly decrease the pH value and increase the organic matter content by as much as 0. 65 units and 1.76 g.kg-1 , respectively; S application could significantly decrease soluble Se and Fe/Mn oxide-bound Se, and significantly increase organic matter-bound Se, however, there was no remarkable effect on exchangeable and residual Se. S could significantly decrease the content of Se(IV) in the soluble Se and significantly increase the content of Se(IV) in the exchangeable Se, with remarkable decrease in Se(VI) content in both fractions, and no remarkable effect on Se(II). S had a profound effect on the uptake of Se by rape seedlings when Se( IV) and Se( VI) were applied. The Se contents in shoot and root of the Se( VI)-treated rape were 7.3 and 3.2 times respectively as high as that of the Se( IV)-treated rape, while with a S rate of 2 mmolL-1, their Se contents were lower than 32.6% and 8.7% of that of the Se(IV)-treated rape. In conclusion, in addition to improving crop growth, appropriate amount of S fertilizer could also reduce soil pH and increase organic content, causing available Se in soil to be Fe/Mn oxide-bound and organic matter-bound, and retarding its transformation to Se( VI), thus reducing Se uptake by rape. This has significant value for regulation of Se content in crops from Se-rich regions, ensuring food quality and safety, benefiting the long-term use of soil Se resources and regional economic development.

Undisturbed soil monolith lysimeter was used to investigate the effectiveness of DCD (dicyandiamide) in reducing N2O emissions in vegetable (Chinese cabbage and pepper) field. Results showed that DCD significantly reduced total N2O emission in vegetable field. Total N2O emissions from the urea treatment without DCD reached 0.215 kg x hm(-2) for Chinese cabbage, and it reduced to 0.109 kg x hm(-2), equivalent to a 49.3% reduction. The total N2O emissions for pepper were much higher compared with those for Chinese cabbage. The total N2O emitted from the urea treatment was 2.32 kg x hm(-2) (without DCD) and it was reduced to 1.14 kg x hm(-2) with DCD application, representing a 50.9% reduction. In the control treatments where no urea was applied, the daily N2O flux was very low and it never exceeded 9 microg x (m2 x h) (-1) for Chinese cabbage and 22 microg x (m2 x h) (-1) for pepper, respectively, but DCD also reduced N2O emissions (33.5% for Chinese cabbage and 33.4% for pepper). In addition, the urea-N emission factor (EF) was 0.15%, 0.99% for Chinese cabbage and pepper without DCD, respectively, and it was reduced to 0.07%, 0.52% when DCD was applied. These results demonstrated the potential of using nitrification inhibitors (DCD) to mitigate N2O emissions in vegetable system.

9 kinds of substrate materials (gravel, aluminite stone, sands, soil, zeolite, ceramic granule, limestone, steel slag and vermiculite) were selected to examine the phosphorus adsorption and removal capacities from runoff by adsorption, captive test and dynamic adsorption experiments. The results showed that these substrate materials had higher removal efficiency for PO4(3-) than those of other phosphorus forms. The adsorption characteristics of the substrates could be described by both Freundlich and Langmuir adsorption isotherms. The equilibrium adsorption capacity of these substrates was in the following order: zeolite, soil and vermiculiteceramic granule, steel slag and limestonegravel, sands and aluminite stone. The dynamic adsorption capacity was zeolite, soil, limeramic granule, limestonesteel slag, gravel and sandsceramic granule and vermiculite. In the meanwhile, the releasing phenomena of phosphorus also could be observed in the captive and dynamic test, particularly for vermiculite, ceramic granule and steel slag. In the dynamic adsorption experiment, the removal efficiency of P-pollutants was ranged from 30% to 87% for the substrate materials except vermiculite, ceramic granule and steel slag. The results suggest that zeolite, limestone and soil are appropriate substrates for removing P-pollutants from stormwater.

The study with pot experiment showed that under the stress of low soil moisture content, the oilseed rape cultivars with high and low boron (B) use efficiency had a higher fresh mass per plant at their seedling stage under high B supply, compared with those under low B supply. The increment was 43.1% and 31.7%, respectively, but no significant difference was observed between the cultivars. Under two B supply levels, the bound water content and semi-bound B distribution proportion in the leaves of the cultivar with high B use efficiency were 11.4% and 1.7%, and 6.9% and 23.8% higher than those of the cultivar with low B use efficiency, respectively. Under normal soil moisture condition, high B supply induced an increase of fresh mass per plant by 11.1% for the cultivar with high B use efficiency and by 27.4% for the cultivar with low B use efficiency, compared with low B supply. Under these two B supply levels, the cultivar with high B use efficiency had a higher content of free water in its leaves, and its leaf free B content was 2 times as much as that of the cultivar with low B use efficiency, which would benefit the B transportation in plant.

MicroRNAs (miRNAs) are non-coding RNA molecules of 21-24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation, and pathogenesis of human diseases including cancer.We analyzed the miRNA expression profiles in 10 pairs of hepatocellular carcinoma (HCC) and adjacent non-tumorous tissue (NT) from 10 non-viral hepatitis patients, using a mammalian miRNA microarray containing whole human mature and precursor miRNA sequences.A total of 15 miRNAs exhibited higher expression in the HCC samples than that in the NT samples, and one miRNA demonstrated lower expression in the HCC samples than in the NT samples. A total of 18 miRNAs identified valid expression only in HCC samples, with six only in NT samples. The chip results were confirmed by Northern blot analysis.Our study may help clarify the molecular mechanisms involved in the pathogenesis of HCC, and miRNAs potentially serve as a novel diagnostic tool of HCC.

An off-line filtering ditch-pond system for controlling storm runoff pollution in urban tourist areas was developed, which could retain the first flush effectively, resulting in the decrease of pollutant concentration and suspended solid average grain size, and the improvement of pollutant retention in runoff. This system could be an effective treatment system for storm runoff pollution, particularly for the scarcity of available land use in urban areas. In 2005, the yearly retention rates of TSS, COD, TN and TP were 86.4%, 85.5%, 83.9% and 82.9%, and during a storm event on June 26, the retention rates of runoff volume, TSS, COD, TN and TP were 67.9%, 97.0%, 89.2%, 94.9% and 96.2%, respectively. This system could also retain most of the suspended solids in runoff.

Effects of molybdenum (Mo) on antioxidative defense system and membrane lipid peroxidation in leaves of winter wheat (Triticum aestivum H. var. Huamai 8) were investigated under low temperature stress. Results of experiments indicate that Mo application in winter wheat induced a dramatic decrease in electrolyte leakage and malondialdehyde content under low temperature stress. The activities of antioxidative enzymes such as superoxide dismutase (SOD, EC 1.15.1.1), peroxidase (POX, EC 1.11.1.7) and catalase (CAT, EC 1.11.1.6) were increased by Mo application and the extents of increase at low temperature were higher than those at normal temperature. Mo application also caused a significant increase in the ascorbic acid (AsA) and proline contents both at normal and low temperature and following the low temperature stress the increases in ascorbic acid and proline contents in Mo-treated winter wheat were higher. There was no significant difference in carotenoid (CAR) content between with and without Mo treatment under normal temperature, while there was a significant increase in Mo treatment under low temperature stress. It could be speculated that Mo application enhanced cold resistance by increasing the capacity to scavenge active oxygen species and alleviating membrane damage in winter wheat under low temperature stress.