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Chaotic systems arise everywhere in control theory and nonlinear vibration. This paper uses a high-precision numerical approach for capturing chaotic attractors of the fractional EI Ni ñ o chaotic systems. The numerical results indicate that some of the chaotic attractors of fractional-order systems are topologically equivalent to those discovered in the integer-order systems, and some unusual attractors of fractional EI Ni ñ o chaotic systems are found by using the present method. [ABSTRACT FROM AUTHOR]

Nitrogen (N) application is the main agricultural management that increases nitrous oxide (N2O) concentration in the atmosphere. Freezing conditions are common phenomenon in the northern China that significantly affect soil N2O emissions through alterations in nutrients availability and microbial population. To develop a comprehensive understanding of how N fertilizer managements affect soil N2O emissions during the freezing process, a lab incubation was conducted in three typical cultivated soils (black soil, fluvo-aquic soil, or loess soil) by adding different N fertilizer sources, including ammonium chloride, sodium nitrate, or urea at different N levels (0, 80, 200, or 500 mg N/kg) at the start of freezing. The N2O emissions in the fluvo-aquic soil were significantly higher than in other soils. The application of nitrate in the fluvo-aquic soil promoted N2O emissions by five- and seven-fold higher compared to ammonium chloride and urea, whereas N2O emissions in black soil were enhanced by application of ammonium chloride. Data indicate that denitrification is the major pathway for N2O production in the fluvo-aquic soil during the freezing process, while ammonia oxidation responses accounts for elevated N2O production in black soil. No significant influence of N fertilizer levels on N2O emissions were found during soil freezing. These results suggest that agricultural practices that focus on mitigation of N2O emissions need to avoid selection of nitrate as N fertilizer source in fluvo-aquic soil prior to the freezing season. Future studies need to focus on how the expression of enzymes and/or shifts in microbial communities respond to different N fertilizers during freezing conditions. [ABSTRACT FROM PUBLISHER]

Field experiments of winter wheat-summer maize rotation were conducted in North China Plain irrigation area to explore the effects of wheat season irrigation with dairy effluent on grain yield, phosphorus uptake, accumulative phosphorus usage efficiency and phosphorus accumulation in soil. The results showed that the irrigation with dairy effluent significantly improved the yields of winter wheat and summer maize. With the increasing of P2O5 carried by dairy effluent into soil, winter wheat yield increased at first and then decreased. When the P2O5 increased 137 kg·hm-2, winter wheat yield increased to the maximum (7646.4 kg·hm-2) and the phosphorus utilization rate was the highest (24.8%). But excessive phosphorus decreased the winter wheat yield and phosphorus utilization efficiency. Summer maize yield and phosphorus uptake increased with the increase of P2O5 carried by dairy effluent. The summer maize yield increased by 2222.4-2628.6 kg·hm-2 and the phosphorus uptake increased by 13.9–21.1 kg·hm-2 in contrast to the control (CK). Under conventional phosphorus fertilization at 88 kg·hm-2, and the summer maize yield increased by 2235.0 kg·hm-2 compared with CK. As the time of irrigation with dairy effluent increasing, the grain yield increased more significantly. The cumulative phosphorus utilization in this rotation system increased year by year. After six seasons of crop harvest, the cumulative phosphorus utilization rate increased into 40.0%–47.7%. Under the experimental condition, two times of irrigation with the dairy effluents in the winter wheat-summer maize rotation system was the best operating mode. [ABSTRACT FROM AUTHOR]

Nitrogen leaching loss in paddy fields is one of the main ways of farmland non-point source pollution. To explore the suitable fertilization of rice fields in the Erhai Lake Basin and reduce the nitrogen loss from paddy fields, a field experiment was conducted by setting single applications of chemical or organic fertilizer, combined organic and inorganic application, and single application of controlled release fertilizer under reduced nitrogen conditions. The results showed that, compared with the conventional fertilization treatment(CF), there was no significant difference in rice grain and straw yield between the single chemical fertilizer treatment(T1) and the organic-inorganic combined treatment(T3); the single organic fertilizer treatment(T2) decreased the rice grain yield by 13.0%, and decreased straw yield by 17.1%; single application of controlled-release fertilizer(T4) increased rice grain and straw yield by 15.7% and 21.0%, respectively. Further, compared with CF, the single application of chemical fertilizer(T1), organic fertilizer(T2), and organic-inorganic combined application(T3) reduced the total nitrogen leaching loss at 30 cm depths by 26.9%, 18.0%, and 33.9%, respectively. The loss of ammonia nitrogen leaching with T1, T2, and T3 decreased by 24.4%, 36.9%, and 36.6%, respectively, and the loss of nitrate nitrogen leaching decreased by 40.2%, 4.8% and 46.4%. The total nitrogen leaching at 60 cm soil depths was reduced by 34.2%, 26.3%, and 42.1%, the loss of ammonia nitrogen leaching was reduced by 31.4%, 35.7%, and 46.6%, and the loss of nitrate nitrogen leaching was reduced by 8.0%, 10.1%, and 23.9% for T1, T2, and T3, respectively. The total nitrogen loss at 30 and 60 cm depths increased by 41.6% and 14.0% in the single application of controlled release fertilizer(T4) treatment. Considering factors such as agronomic and environmental benefits of different fertilization modes, T1 and T3 are suitable environmentally friendly alternative fertilization modes.

Sewage sludge contains a high level of nutrients, such as nitrogen, phosphorus, potassium and organic matter, with a high recovery value. The presence of heavy metals in sludges has become a major limiting factor in the utilization of these sludges. Therefore, the removal of heavy metals before land application of sewage sludge has become very necessary. Two municipal sewage sludges (S1 and S2) were collected from municipal wastewater plants in Wuhan city and were studied by oscillation leaching experiments with combination of saponin and citric acid to evaluate their removal efficiencies for Cu, Pb and Zn at different volume ratios (20:1-1:20), ratios of solid to liquid (1:20-1:80), reaction times (0-2880 min), and leaching times (1-4). The heavy metal fractions in the sewage sludges were analyzed before and after leaching to study changes in the stability and mobility of heavy metals by calculating a stability factor[relative bonding strength of heavy metals (I R )] and a mobility factor (MF). The results show that the highest removal efficiency of Cu, Pb, and Zn was 43.16% (S1), 32.45% (S2) and 38.69% (S1), respectively under the removal conditions of a volume ratio (saponin:citric acid) of 5:1, solid-liquid ratio of 1:60, and leaching time of 1440 min. The removal efficiencies of Cu and Pb were significantly enhanced and Zn had a small increase with longer leaching times, which was significantly different after two to three washing times. The highest removal rate of Cu, Pb, and Zn was 78.89% (S1), 77.08% (S2) and 49.39% (S1) after four washing times, respectively. Beyond acid soluble and reducible fractions, other forms of heavy metals have very low removal rates after a single leaching. The removal rates of heavy metal fractions increased by increasing the leaching time, particularly for Pb, which in the residual fraction was significantly increased. The stability and mobility of heavy metals changes after each leaching. For example, the I R of Cu, Pb, and Zn increased to 43.63% (S1), 39.44% (S2) and 32.00% (S1), respectively, and the MF of these heavy metals decreased from 30.19% to 79.45% in the sewage sludges after four washing events.

The present study was conducted to investigate the prevalence of HPV infection in epithelial ovarian cancer (EOC) in Hunan province. DNA samples were collected from paraffin embedded ovarian tissue from 322 patients with EOC, 99 with ovarian benign tumors and 199 normal persons. The polymerase chain reaction and direct sequencing were used to identify the HPV types in the samples. The relationship between the infection of human papillomavirus (HPV) and the epithelial ovarian carcinoma (EOC) was investigated combined with clinical data. The prevalence of HPV18 and HPV33 in EOC group and benign group was higher than in the normal group. HPV18 and HPV33 may play a role in the development of both EOC and ovarian benign tumor and may participate in the development of EOC with traditional risk factors, family history and abortion, possibly exerting synergistic effects..

Field experiments of winter wheat-summer maize rotation were conducted in North China Plain irrigation area to explore the effects of wheat season irrigation with dairy effluent on grain yield, phosphorus uptake, accumulative phosphorus usage efficiency and phosphorus accumulation in soil. The results showed that the irrigation with dairy effluent significantly improved the yields of winter wheat and summer maize. With the increasing of P2O5 carried by dairy effluent into soil, winter wheat yield increased at first and then decreased. When the P2O5 increased 137 kg · hm(-2), winter wheat yield increased to the maximum (7646.4 kg · hm(-2)) and the phosphorus utilization rate was the highest (24.8%). But excessive phosphorus decreased the winter wheat yield and phosphorus utilization efficiency. Summer maize yield and phosphorus uptake increased with the increase of P2O5 carried by dairy effluent. The summer maize yield increased by 2222.4-2628.6 kg · hm(-2) and the phosphorus uptake increased by 13.9-21.1 kg · hm(-2) in contrast to the control (CK). Under conventional phosphorus fertilization at 88 kg · hm(-2), and the summer maize yield increased by 2235.0 kg · hm(-2) compared with CK. As the time of irrigation with dairy effluent increasing, the grain yield increased more significantly. The cumulative phosphorus utilization in this rotation system increased year by year. After six seasons of crop harvest, the cumulative phosphorus utilization rate increased into 40.0%-47.7%. Under the experimental condition, two times of irrigation with the dairy effluents in the winter wheat-summer maize rotation system was the best operating mode.

The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group, followed by the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve fibers, and a completely degraded and resorbed conduit, in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group. These results indicate that bridging 10-mm sciatic nerve defects with a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is beneficial for the regeneration and functional reconstruction of sciatic nerve. Better regeneration was found with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel grafts than with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells grafts and the autologous nerve grafts.

The experiment was conducted to investigate the effects of different forms of nitrogen application (ammonium, NH4(+) -N; nitrate, NO3(-) -N; and amide-N, NH2-N) and different concentrations (40, 200 and 800 mg/L) on N2O flux from the fluvo-aquic soil in a lab-simulated freezing and thawing process. N2O flux slowly decreased with soil freezing, and then increased slowly with soil thawing, reaching a peak at the initial thawing stage. The average N2O fluxes with addition of NH4(+) -N, NO3(-) -N and NH2 -N are 119.01, 611.61 and 148.22 microg x (m2 x h) (-1) respectively at the concentration of 40 mg/L; 205.28, 1084.40 and 106.13 microg x (m2 x h)(-1) at the concentration of 200 mg/L; 693.95, 1 820.02 and 49.74 microg x (m2 x h)(-1) at the concentration of 800 mg/L. The control is only 100.35 microg x (m2 x h)(-1). N2O flux with addition of NH4(+) -N and NO3(-) -N increased with increasing concentration, ranging from 17.49% to 425.67% for NH4(+) -N, and 563.38% to 1 458.6% for NO3(-) -N compared with control. There was a time lag achieving stable N2O emission flux with concentration increase. In contrast, by adding NH2 -N to soil, N2O flux decreased with increasing concentration. In sum, inorganic nitrogen such as NH4(+) -N or NO3(-) -N fertilizer incorporated in soil enhanced the cumulative N2O flux from the fluvo-aquic soil relative to amide-N. This study suggested that ammonium and nitrate concentration in overwintering water should be less than 200 mg/L and 40 mg/L in order to reduce N2O emissions from soil, regardless of amide-N.

Objective: To investigate the inhibition of HPV18E6 gene in HeLa cell transfected with plasmid expressing human papilloma virus 18 E6 (HPV18E6) short hairpin RNA (shRNA)., Methods: We synthesized two HPV18E6 shRNA frames and sub-cloned them into pSUPER which can express shRNA in mammalian cells to construct pE6-1shRNA and pE6-2shRNA which were mutant in E6 shRNA frame. The pE6-1shRNA, pE6-2shRNA and pcDNA3.1 were co-transfected into HeLa cells by cationic liposome respectively and the positive transfectants were selected by G418. The HPV18E6 mRNA and protein expression level was detected by semi-quantitative RT-PCR and streptavidin-peroxidase conjugated method (SP) to assay the inhibitory effects of pE6shRNA., Results: We successfully constructed several new HeLa cell lines transfected with pE6-1shRNA and pE6-2shRNA. In the HeLa cells without transfection and the HeLa cells transfected with pE6-1shRNA plasmid, the HPV18E6 mRNA levels were 1.14 +/- 0.45, 0.76 +/- 0.28 respectively, and the difference of HPV18E6 mRNA levels was significant (P < 0.05). The inhibition efficiency of HPV18E6 gene mRNA was 33.3% and the HPV18E6 protein levels were declined after transfection with pE6-1shRNA. In the HeLa cells transfected with pE6-2shRNA and pSUPER plasmids, HPV18E6 mRNA and protein expression levels were not different from those in wild HeLa cells., Conclusions: The pE6-1shRNA plasmid can inhibit HPV18E6 expression in HeLa cells, which is persistent, specific and heritable.

A composite microbial system, including a strain of Candida tropicalis (W3), a strain of Lactobacillus plantarm(WY3) and three strains of basidiomycete pL104, pL113 and C33, was chosen to degrade corn straw. The final pH was acid owing to the inoculation of acidogenic bacteria, and under this condition the composite fungi system could produce complex enzyme to destroy the compact structure of corn straw. The experimental results showed that the biomass of composite fungi could reach up to maximum when the pH value was 4.5. Through the bio-degradation by combining acidogenic bacteria with the composite fungi system, the cellulose, hemi-cellulose and lignin degradation rates of corn straw powder were 26.36%, 43.30% and 26.96%, respectively. And the gross crude protein content increased 60.41%. This study provided the evidence for the feasibility of developing a composite microbial system with high capability of degrading straw lignocelluloses in order to make reasonable use of straw resource and protect rural eco-environment.

In present study, a method for genotyping for human platelet antigen (HPA) systems by means of the polymerase chain reaction amplification with sequence-specific primers (PCR-SSP) technique was developed and employed to determine the human platelet antigen frequencies in the Chinese population. Primers sets were designed to allow PCR amplification for five systems using the same assay conditions. Platelets from 110 random Chinese blood donors were typed for human platelet alloantigens HPA-1 to -5 by the method. The results showed that the HPA genotypic frequencies observed in the 110 donors were 0.91 and 0.09 for HPA-1a and HPA-1b, 0.86 and 0.14 for HPA-2a and HPA-2b, 0.60 and 0.40 for HPA-3a and HPA-3b, 0.92 and 0.08 for HPA-4a and HPA-4b, and 0.85 and 0.15 for HPA-5a and HPA-5b, respectively. In conclusion the method is feasible and practical and may be available to typing for HPA in the clinical laboratories.