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Nitrogen loss from rice systems is an important source of agricultural non-point source pollution. Many studies revolve around reducing the rate of nitrogen fertilizer application. However, studies examining the characteristics of nitrogen loss in multiple loss paths （runoff, leaching, and lateral seepage） under different straw and fertilizer managements are lacking. Therefore, a study was carried out based on a rice field planted for more than 20 years with straw continuously returned to the field for more than 5 years in Taihu lake basin. The effects of straw and fertilizer managements on nitrogen loss in different paths during the whole growth period of rice were studied. Moreover, straw and fertilizer managements were evaluated by their production suitability and environmental friendliness based on crop yield, nitrogen use efficiency, and nitrogen loss. The results showed that straw removal from the field increased the response sensitivity of nitrogen accumulation in plant tissue to nitrogen application. The nitrogen loss in the rice season was 9-17 kg·hm -2 , accounting for 5%-7% of the nitrogen application rate. Straw removal increased the risk of nitrogen loss when soaking water discharged. Straw returning could decrease the nitrogen loss by more than 15%, though the effect of straw on nitrogen loss via lateral seepage was not clear. Furthermore, the suitable substitution of organic fertilizer （30% in this study） could respectively reduce the amount of nitrogen loss via runoff, leaching, and lateral seepage by 16%, 26%, and 37% compared with the fertilizer application under the same nitrogen gradient. In conclusion, the implementation of straw returning and fertilizer type optimization measures effectively reduced the nitrogen loss for unit weight of rice production and realized the balance between agricultural production and environmental protection.

The intensity of crop farming fertilizer input is generally high in the Taihu Lake Region, with chemical fertilizer as the main form. Due to inappropriate fertilizer application, nitrogen and phosphorus loss have occurred, causing serious agricultural non-point source pollution. The Ministry of Agriculture and Rural Affairs of China has launched the "zero-growth action for chemical fertilizer use" and "replacement action with organic fertilizer" ("two actions" for short) campaigns since 2015. Local agricultural sectors adjusted fertilizer application strategies of crop farming to respond to the call of two actions. However, the current research is still focusing on reducing the total amount of fertilizer application and increasing the area of organic fertilizer application, which is mainly based on grain crops. The study of agricultural environment problems is still lacking, especially in vegetable, orchard, and tea systems. Therefore, a study was carried out in the typical agricultural area of Suzhou City Wuzhong District from 2019 to 2021. Based on the data of the amount of nitrogen and phosphorus removal by harvest crops and soil nitrogen and phosphorus residual in paddy, vegetable, orchard, and tea systems, the loss was estimated. The responses of nitrogen and phosphorus loss from typical crop systems to fertilizer application strategy adjustments were studied through analysis of different factors. The results showed that fertilizer application rate was the key to control nitrogen and phosphorus loss. Additionally, the suitable replacement ratio of organic fertilizer could further reduce the loss risk. It should be noted that the urgent demand for nutrients in crop growth should be considered to determine the timing of organic fertilizer application, and agricultural machinery should be used to assist organic fertilizer application to reduce labor output if possible. Fertilizer efficiency was the core of environmental friendliness and economic benefits of crop farming. Hence, improving fertilizer efficiency should be the guidance of fertilizer application strategy adjustment. Our suggestions on the adjustment of fertilizer application strategy in different crop systems in the study area are as follows:attention should be paid to the nitrogen, phosphorus, and potassium input ratio in paddy systems to further reduce nitrogen and phosphorus loss. Planting structure adjustment should be emphasized in vegetable systems to promote fertilizer efficiency. The strategy to satisfy both tea and orchard growth from a composite system perspective would help to build crop systems that meet the needs of green agricultural development.

Farmland is the important soil carbon pool of terrestrial ecosystems and organic nutrient pool for crop growth. To clarify the impact of climate warming on the soil carbon pool, this study analyzed the effects of warming and fertilization on soil organic carbon and its labile components under rice-wheat rotation using a free-air temperature increase system. The variation in soil carbon pool management index (CPMI) was also evaluated. The results showed that the combined effects of warming and fertilization on soil organic carbon content and labile organic carbon components were insignificant. Warming increased the soil organic carbon (SOC) content, and the differences between warming and the ambient control in total organic carbon (TOC) and recalcitrant organic carbon (ROC) reached a statistically significant level. Compared with those under the ambient control, the contents of TOC, ROC, and labile organic carbon (LOC) subjected to warming increased by 7.72%, 7.42%, and 10.11%, respectively. The increased microbial biomass carbon (MBC) content (20.4%) and decreased particulate organic carbon (POC) content (36.51%) may have been the main reason for the variation in SOC. Warming showed no significant effect on soil dissolved organic carbon (DOC) content, whereas it markedly reduced its soluble microbial by-product components (41.89%). The results also showed that fertilization had no significant effect on soil TOC, ROC, and LOC, but it notably reduced the contents of DOC and POC and increased the MBC content. Compared with those under the control without fertilization, the contents of DOC and POC subjected to fertilization decreased by 35.44% and 28.33%, respectively, and the MBC content increased by 33.38%. Additionally, fertilization tended to increase the anthropogenic humus component (5.13%) and soluble microbial by-product component (29.41%) in dissolved organic matter and reduce the terrestrial humus component (13.33%). Warming and fertilization both tended to improve soil CPMI. Affected by SOC and LOC, the increase in soil carbon pool index and soil lability index were the main reason for the increase in soil CPMI under warming and fertilization, respectively. Overall, the results revealed that climate warming can affect the soil carbon pool by changing soil labile carbon components, which are not affected by fertilization.

Clayey soil seriously affects water-holding capacity and nutrient movement. Adopting appropriate agronomic measures to optimize the distribution of soil inorganic nitrogen (SIN) and reduce the nitrogen (N) loss in this soil is the key to agricultural sustainable development. To clarify the effect of deep fertilization of slow/controlled release fertilizer with sowing on N loss in a clayey soil wheat field, two types of fertilizers, conventional fertilizer (CN) and slow/controlled release fertilizer (RCU), were selected in this study. Here, we evaluated the effects of these two fertilizer types on wheat yield, seasonal N runoff loss, ammonia volatilization, and N 2 O emissions in wheat fields in two typical fertilization modes (manual surface sowing and spreading (B) and belowground fertilization of slow/controlled release urea with mechanized strip sowing (D)). The temporal and spatial distribution characteristics of SIN in topsoil were also analyzed. The results showed that under the same fertilizer type, the wheat yield of D treatment was significantly higher than that of B treatment, whereas the yield of RCU was notably higher than that of CN under the same fertilization mode. D-RCU achieved the highest yield of 6.97 t·hm -2 . The seasonal N losses from runoff and ammonia volatilization were higher than that from N 2 O emissions, and the responses of different N loss pathways to fertilizer types and fertilization methods were diverse. Fertilizer type and runoff occurrence time were the main influencing factors of N runoff loss, and N runoff loss of the RCU treatment was higher in the non-fertilization period. Unfortunately, affected by annual rainfall pattern, the seasonal N runoff loss of the RCU treatment (20.35 kg·hm -2 ) was significantly higher than that of the CN treatment (10.49 kg·hm -2 ). The late growth period was the main phase of ammonia volatilization, and the later period was jointly affected by fertilization modes and fertilizer types. The B-CN treatment induced the highest seasonal ammonia volatilization (18.15 kg·hm -2 ), which was significantly higher than that of the other treatments (7.31-8.38 kg·hm -2 ). Additionally, the D-RCU treatment (2.41 kg·hm -2 ) tended to reduce the N 2 O emissions in comparison to that in the B-CN treatment (4.02 kg·hm -2 ). The results also indicated that the horizontal movement of SIN was higher than the vertical movement. Deep fertilization of RCU was conducive to optimizing the spatial and temporal distribution of SIN, which was the main reason for the increase in wheat yield and the control of N loss from wheat fields. These results suggest that RCU is a suitable alternative fertilizer for increasing yield and reducing N loss in clayey soil wheat fields; D-RCU can increase the wheat yield and reduce ammonia volatilization and N 2 O emissions in wheat fields by optimizing the spatial and temporal distribution of SIN, and its increasing effect on N runoff loss in the non-fertilization period deserves attention.

Hydrochar can mitigate ammonia volatilization when applied in paddy fields due to its acidity and adsorption property. To realize the recycling of agricultural biowaste as well as the control of nutrient loss from paddy fields, a simulation soil-column experiment with wheat straw hydrochar (WHC) and water-washed hydrochar (W-WHC) was conducted to evaluate the performance of rice yield and ammonia volatilization from paddy fields. The results showed that WHC and W-WHC applied in paddy fields both increased the rice yield and the increased effect at low application rate (0.5%) was higher than that at high application rate (1.5%). In comparison with the control treatment (CKU), the rice yields achieved from low application rate treatments for WHC and W-WHC increased by 17.16% and 20.20% respectively. Except for the equal emission rate between W-WHC with low application rate and CKU treatments, hydrochar (WHC, W-WHC) addition reduced the ammonia volatilization from paddy fields when compared with the CKU. Among them, the ammonia volatilization levels from low-application WHC and high-application W-WHC treatments were significantly lower than that from the CKU treatment, reduced by 31.01% and 17.40%, respectively. Based on the analysis of ammonia volatilization during different fertilization stages, the control effect of hydrochar addition on ammonia volatilization was mainly benefited from tillering and panicle fertilizer stages. The change in the nitrogen concentration of surface water at the tillering fertilizer stage and in pH at the panicle fertilizer stage with the addition of hydrochar was the main driving factor for the reduction in ammonia volatilization. The results show that sufficient amounts of hydrochar derived from wheat straw application can increase crop yield while reducing ammonia volatilization from paddy fields. This method provides an effective route for recycling agricultural biowastes.

Ammonia volatilization emissions constitute the main pathway of nitrogen loss from paddy systems. Present control technologies are based on reducing the amount of nitrogen fertilizer applied. However, ratio of nitrogen loss through ammonia volatilization emissions has not changed, and it has become a bottleneck for promoting nitrogen use efficiency. Therefore, in order to study the effects of film materials on ammonia volatilization emissions, a two-year field plot experiment was carried out with agricultural waste powder and amphipathic molecule materials spread on surface water after nitrogen fertilizer application in paddy system. The results showed that film materials could reduce nitrogen loss through ammonia volatilization by 19%-31% in the paddy season, and this part of nitrogen was accumulated in soil or assimilated by paddy tissue. The ammonium concentration and pH in the surface water and film materials were the major control factors of ammonia volatilization emissions with nitrogen fertilizer application. Moreover, further reductions in ammonia volatilization emissions could be achieved by film materials after reducing nitrogen fertilizer application. Differences in the effect mechanisms of the film materials provide flexible options for practical agricultural production to meet demands.

Biochar application on farmlands is an efficient way to realize agricultural/forestry biowaste recycling in parallel with carbon sequestration. Recently, hydrochar produced by hydrothermal carbonization processes has attracted attention due to the advantages over conventional pyrolytic production (i.e., easier production process, higher carbon yield, reduced energy consumption, and lower flue gas emissions). To clarify the effects of hydrochar applied in farmlands on crop production, as well as to realize the recycling of agricultural/forestry biowaste resources, this study evaluated the effects of four types of modified-hydrochar addition on rice yield and nitrogen uptake in two typical soils and the possible influencing factors through soil-column experiments and material characterization. The results showed that sawdust hydrochar and/or straw hydrochar could increase rice yield and nitrogen uptake, as well as reduce N loss, in both treated soils after physical or biological modification, an effect that was independent of the application rate (5‰, 15‰; mass fraction). In comparison to the control, the rice yield and nitrogen uptake of hydrochar-addition treatments increased by 9.2%-20.7% and 7.7%-17.0% respectively. Sawdust hydrochar, with a wider C/N material, was conducive to improving nitrogen uptake in high fertility soils; meanwhile, the nitrogen utilization in low fertility soils was less affected by the type of hydrochar due to the limitations imposed by multiple factors. The results of material characterization showed that the surface of the hydrochar was rich in nutrients; the pore structure of hydrochar after washing or biological modification was greatly improved, the relative content of C was remarkably reduced, and the relative contents of N and O notably increased, which could affect nutrient fixation and supply. Thus, the improved pore structure and increased contents of N and O of modified hydrochars may be the key drivers for the increase in rice yield and nitrogen uptake with hydrochar addition. These results suggest that modified hydrochar is beneficial to realizing agricultural/forestry biowaste recycling and improving crop yield and nitrogen utilization, as well as reducing N loss from farmlands.

The contribution of crop planting to agricultural non-point source pollution should not be underestimated in China. Although many modern technologies have been developed to prevent non-point source pollution in recent decades, their impacts on pollution control in farmland are far from expectation. The application of technologies for non-point source pollution control for crop farming has been delayed due to unclear technical parameters and application effectiveness. Therefore, based on studies of the non-point source pollution control for crop farming in China and abroad that were published in the last 20 years, the present research was carried out to determine the development process of planting non-point source pollution control technologies and to illuminate the framework construction. The technologies in different fields and directions were compared by their effects on fertilizer input,yield, and pollutant emission. The development trend in the field of prevention and control technologies for planting non-point source pollution was subsequently predicted. In addition, a technical framework was developed with 3 fields (pollutant source reduction, pollutant interception in the migration process, and nutrient recycling) and 14 directions. The analysis showed that the technologies for reducing pollutants from the source have attracted the most (and increasing) concern with many research directions, and that many of the studies in this field have focused on the regulation of fertilizer application. On the contrary, there is a lack of technologies in the fields of pollutant process interception and nutrient recycling. Promoting nutrient-use efficiency, regulating nutrient transformation, and using soil supplements will be the main entry points for non-point source pollution control for crop farming. Furthermore, technologies will operate better with the help of farmland infrastructure and downstream purification systems.

Lanthanum (La)-based materials have shown great potential for phosphate removal owing to the strong affinity between La and phosphate. In this study, magnetic hydrothermal biochar immobilized La(OH) 3 (La-MHTC) were prepared and used as phosphate adsorbents. Hydrochar was produced by the hydrothermal carbonization process (220℃, 2 h). Magnetic La-MHTC with different La-to-Fe mass ratios were synthesized by the co-precipitation method. Subsequently, La-MHTC was applied to remove phosphate from wastewater. Results indicate that La-MHTC (with a La-to-Fe mass ratio of 2:1) exhibited excellent magnetic properties for easy recovery and high phosphate adsorption capacity up to 100.25 mg·g -1 . Effective phosphate removal was obtained over a wide pH range of 3-10. The absorption isotherm and kinetics were better fitted by the Langmuir model and the pseudo second-order model, respectively, which showed a fast adsorption rate and exhibited superior La utilization efficiency. The La-MHTC has strong selectivity for phosphate in the presence of coexisting ions (Cl - , NO 3 - , and SO 4 2- ). The adsorption-desorption experiment suggested its excellent stability and cyclic utilization. In addition, La-MHTC was applied to treat real domestic wastewater, efficiently reducing the phosphate concentration (from 0.87 mg·L -1 to 0.05 mg·L -1 ). Electrostatic attraction and inner-sphere complexation between La(OH) 3 and P via ligand exchange were the main mechanisms of phosphate adsorption by La-MHTC.

Hydrochar, as a product of the hydrothermal carbonization of biomass, has good application prospects for the NH 3 volatilization reduction in rice fields due to its rich pore structure and functional surface. In this study, hydrochar was applied as a soil conditioner to paddy soil. A soil column experiment was conducted to investigate the effect of hydrochar on NH 3 volatilization throughout the growth period of rice. The experiment was conducted with three treatments:CKU (control without hydrochar); SHC (sawdust hydrochar); and W-SHC (water-washed sawdust hydrochar). The application rate of SHC and W-SHC was 0.5% ( w/w ). The study investigated the effects of different hydrochars on the pH and concentrations of NH 4 + -N in floodwater, the flux and accumulation of NH 3 volatilization, and the yield-scale cumulative emission of NH 3 volatilization. Results show that the SHC treatment significantly reduces cumulative emissions of NH 3 volatilization and the yield-scale cumulative emissions of NH 3 volatilization ( P <0.05), which were 32.42% and 47.61% lower than CKU, respectively. The effect of W-SHC on ammonia volatilization reduction was slightly weaker, as the cumulative emissions of NH 3 volatilization and the yield-scale cumulative emissions of NH 3 volatilization decreased by 10.14% and 27.71%, respectively, compared with CKU. The NH 3 volatilization reduction was possibly related to the disturbance of pH and the decrease in NH 4 + -N concentrations in the floodwater because of the application of hydrochar. Compared with CKU, both SHC and W-SHC treatments reduced the pH and NH 4 + -N concentration in the floodwater. The impacts were more obvious in the rice base fertilizer period (BF) and the first supplemental fertilizer period (SF1) than in the second supplemental fertilizer period (SF2). The soil urease activity was significantly inhibited by hydrochar ( P <0.05), and the abundance of soil ammonia-oxidizing gene (AOA, AOB) also significantly increased after application of SHC ( P <0.05). This resulted in the enhanced efficiency of ammonia-oxidizing, which had an effect on the reduction of the NH 4 + -N concentrations in the floodwater. This study provides theoretical and experimental data support for the application of hydrochar in agro-environments with regard to ammonia volatilization reduction in paddy fields.

Objective: To explore the clinical effect of Qufu Shengji ointment(QFSJO) in promoting the wound healing after trauma., Methods: From January 2014 to June 2018, 60 patients with soft tissue injury, skin defect and wound infection caused by violent trauma were admitted, including 32 males and 28 females, aged from 18 to 65 years, with an average age of 41.3 years. Among them, 30 patients were treated with QFSJO (QFSJO group) and 30 patients were treated with normal saline iodophor (control group). The reduction rate of wound area, the days of decayed flesh, the time of new epithelium and the recovery rate of 28 days after dressing change were compared between the two groups., Results: In the QFSJO group, after using large dose of QFSJO, the pus of the wound increased, the granulation grew, and the new epithelium appeared on the edge of the wound, showing a rapid healing phenomenon. The wound healing rate of QFSJO group was higher than that of the control group at all time points, and the time of decaying flesh and new epithelium appeared in QFSJO group was earlier than that of the control group. The recovery rate of QFSJO group was significantly higher than that of the control group( P <0.05). All the patients were followed up, and the duration ranged form 6 to 12 months, with an average of 9.4 months. The exposed areas of bone and teadon were covered well. The vital signs of the two groups were stable and no adverse reactions occurred., Conclusions: QFSJO can promote the growth of granulation tissue, promote the production of new skin, and accelerate the healing of infectious wound after trauma., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© 2019 by the China Journal of Orthopaedics and Traumatology Press.)

Nitrification inhibitor and biochar are commonly used as soil synergists. Among them, nitrification inhibitor can increase crop yields and N use efficiency, while biochar is a relatively new way of using biomass resources and has certain adsorption characteristics. In order to reduce nitrogen loss and environmental pollution caused by ammonia volatilization in paddy fields, a pot experiment with chemical fertilizer application (CN) as a control was conducted to study the effects of biochar (B), nitrapyrin (CP), and compound application (BCP) on pH, NH 4 + -N concentration dynamics in the flood water, rice yields, and ammonia volatilization from paddy fields. The results showed that the application of these two synergists had no significant effect on rice yields, and the nitrification inhibitors had a tendency to increase rice yields. The two synergists significantly increased ammonia volatilization from paddy fields, accounting for 25%-35% of the total N rate. Ammonia volatilization during periods of fertilizer application accounted for 86%-91% of the total loss, representing the main period of ammonia volatilization. Compared with the CN treatment, the CP treatment increased NH 4 + -N concentrations in flood water and the loss of ammonia via volatilization, which was increased by 59.18% and mainly occurred during a week after the basal fertilization(138%) and spike fertilization (48%), and non-fertilization stage (78%). Biochar had a promoting effect on ammonia volatilization with typically phased characteristics. The initial increasing effect of biochar on ammonia volatilization was higher than during the later stages, when NH 4 + -N concentrations and the pH of flood water showed the same trend. In addition, the coupling of nitrification inhibitor and biochar significantly increased the total loss of ammonia via volatilization loss due to the promotion effect of CP and B. The problem of increased ammonia volatilization loss caused by the application of nitrification inhibitors requires further research.

Building a nutrient channel between eutrophic water and agricultural fields could reduce nutrient input into fields and alleviate eutrophication by returning nitrogen. In order to determine the feasibility of returning nitrogen by biochar loading, a rhizobox experiment was conducted with two nitrogen applied methods, namely SN (applied nitrogen by nitrogen fertilizer solution) and BN (applied nitrogen by nitrogen-loaded biochar). The results showed that BN, in comparison with SN, decreased the biomass and nitrogen uptake of the aboveground paddy by 16% and 14%, respectively, increased biomass root-shoot ratios by 25%-27%, and reduced nitrogen recovery use efficiency. Two nitrogen application methods affected the length and volume of paddy adventitious roots. Paddy underground biomass and nitrogen uptake were positively correlated with soil ammonium content, whereas paddy aboveground nitrogen uptake was negatively correlated with root tips. It was suggested that the paddy biomass and nitrogen uptake would be influenced when nitrogen was applied solely by nitrogen-loaded biochar. However, no affinity and no significance in nitrogen use efficiency were found for plant uptake between chemical nitrogen and biochar-loaded nitrogen. Additionally, biochar promoted soil mineral nitrogen content for further plant uptake. Therefore, biochar could be used as the carrier for returning nitrogen from waterbodies to fields. The replacement rate of chemical nitrogen fertilizer is the key to influencing plant growth and needs future study.

The effects of sewage irrigation on the growth of rice seedlings and soil environment under wheat straw returning were examined with a pot experiment. Root morphology, root activity, tiller number, plant height, dry matter accumulation of rice seedling, soil ferrous ions content, organic acid content and enzyme activity were measured. The results showed that sewage irrigation significantly increased the number of tillers and root activity at 41 days after transplanting under no N fertilizer application. Under the same N input level, sewage irrigation combined with N fertilizer promoted the growth of rice seedlings and root, and increased the root length, root surface area, root volume, root activity, tiller number and dry matter accumulation. Sewage irrigation significantly reduced the contents of soil ferrous ions and organic acid, while significantly increased the activities of soil urease and catalase. These results indicated that the combination of sewage irrigation and N fertilizer could effectively reduce the negative effect of straw returning on rice seedling and thus enhance soil fertility and quality.

In order to reduce the ammonia volatilization in paddy fields, seven treatments were evaluated. These included three slow-release nitrogen fertilizers[sulfur-coated urea (SCU); resin-coated urea (RCU); release bulk blending fertilizer (RBB)], two fertilization modes[single base fertilization (B) and combined with panicle fertilizer (BF)], and conventional split fertilization (CN). The effects of side deep fertilization for slow-release nitrogen fertilizers on ammonia volatilization and surface water nitrogen dynamics were examined using a rice transplanter with a fertilizer sowing mechanism in the Taihu Lake region. The results showed that total nitrogen and ammonium nitrogen concentration in the surface water of the SCU treatment in the base period were higher, and those for RCU and RBB were lower than in the CN treatment. The cumulative ammonia volatilization during the whole rice season varied among different types of slow-release nitrogen fertilizers from 3.84% to 28.17% of the total N applied. The nitrogen loss from ammonia volatilization using the three slow-release nitrogen fertilizers was decreased when compared with conventional split fertilization. The ammonia volatilization loss exhibited the following relationship for the treatments:CN, B-SCU > BF-SCU, BF-RBB, BF-RCU, B-RBB, and B-RCU. When the slow-release nitrogen fertilizers were applied in single base fertilization, the total ammonia volatilization for the SCU was significantly higher than those for the RCU and RBB, while no significant differences were detected when these three slow-release fertilizers were combined with panicle fertilizer. Moreover, although the ammonia volatilization of BF-SCU was lower than that of B-SCU, those of BF-RCU and BF-RBB were higher than those with the B-RCU and B-RBB treatments, respectively. There are no significant differences for nitrogen volatilization when any of these three different fertilizers are applied as B or BF. The results for the emissions during ammonia volatilization during different stages indicated that the ammonia volatilization of SCU at the basal-tillering fertilization stage (7.54%) and the tillering-panicle fertilization stage (16.04%) were higher than those of the panicle fertilization-mature stage. The N loss from ammonia volatilization for RBB in the base-tillering fertilization stage (2.91%) increased more than in the tillering-panicle fertilization stage and panicle fertilization-mature stage. For RCU treatment, the highest rate for ammonia volatilization was detected at the panicle fertilization-mature stage (2.75%). Compared with the single base fertilization mode, ammonia volatilization during the panicle fertilization-mature stage was increased when combined with panicle fertilizer (BF) for the slow-release fertilizer. There was no obvious correlation between the N loss with ammonia volatilization for the three slow-release nitrogen fertilizers and the concentration of ammonium nitrogen in surface water during the panicle fertilization-mature stage.

In Taihu Lake region, more and more paddy fields are being converted to vegetable fields, which cause serious soil acidification and decreased soil nitrogen retention. In this study, calcium carbonate and biochar were used as acidification amendments to test their ability on soil acidification remediation and soil nitrogen retention improvement. Calcium carbonate and biochar addition rates were determined by pH buffering curves. An incubation experiment with and without nitrogen fertilization and multi-leaching simulation tests were conducted. The soil nitrogen mineralization rate, dynamics of the nitrogen content in soils and leachates, and soil pH were measured. The results showed that 3.92×10 -2 mol·kg -1 calcium carbonate and 27.73 g·kg -1 biochar should be added into the tested acidified vegetable soil to recover the original pH value. Without nitrogen fertilization, the addition of calcium carbonate increased the soil nitrogen mineralization rate by 37% but had no significant effect on mineral nitrogen content. However, biochar addition significantly improved the soil nitrogen mineralization rate by 35%-44% and nitrate content by 42%-58%. Nitrogen leaching loss was cut down by 42%-57% in biochar addition treatment because of the lower leachate volume and nitrogen concentration, while calcium carbonate addition increased nitrogen leaching loss by 12%-76% because of the higher leachate nitrogen concentration. After leaching, the soil pH decreased for all the treatments. The soil pH change was the lowest for calcium carbonate addition treatment under no nitrogen fertilization and the lowest for biochar addition treatment under nitrogen fertilization. This result suggests that calcium carbonate is more applicable for seriously acidified soils which are fallowed and biochar is more suitable for the intensified vegetable fields because it can improve the soil nitrogen retention and soil pH, and reduce the nitrogen leaching loss.

A pot experiment was conducted to study the effect of straw returning and domestic sewage irrigation on the dynamics of NH 4 + -N concentration and pH in the flood water, and ammonia volatilization of paddy fields. The results showed that the NH 4 + -N concentration in flood water was significantly increased by wheat straw returning while significantly decreased by domestic sewage irrigation. The cumulative ammonia volatilization in the whole rice season under tap water irrigation and straw removal treatment was 58.29 kg·hm -2 , accounting for 24.29% of the total N applied. The N loss ratio of ammonia volatilization was significantly increased to 45.66% by wheat straw returning, while significantly decreased to 17.26% under straw removal and 32.72% under straw returning by domestic sewage irrigation. Significant positive interaction was observed between straw incorporation and domestic sewage irrigation on ammonia volatilization loss. The average N loss from ammonia volatilization during the tillering stage was the highest among the three fertilization stages, accounting for 7.38%-24.44% of the total N applied. In addition, ammonia volatilization fluxes showed a significant positive correlation with the flood water NH 4 + -N concentration, irrespective of the irrigation water, but had no significant correlation with pH. These results indicated that straw returning increased ammonia volatilization losses, whereas domestic sewage irrigation could effectively reduce ammonia volatilization losses and simultaneously replace 44.41% of chemical nitrogen fertilizer by the N contained in the domestic sewage. The combination of domestic sewage irrigation and straw returning would be an ecological and environmental-friendly measure for rice nitrogen management in Taihu Lake region.

Objective: To investigate the clinical characteristics, therapeutic outcomes and prognostic factors of primary central nervous system lymphoma (PCNSL)., Methods: Clinical records of 31 cases of PCNSL were collected, the clinical charactenstics were analyzed retrospectively. Survival curves were estimated using Kaplan-Meier survival methodology and statistical significance of continuous variables was assessed via the Cox proportional hazard model., Results: The median age was 52 years, with a ratio of male to female 1:1. Headache/dizzy/limb numbness were the most common presentation and the lesions of PCNSL were primarily located at the frontal, parietal, temporal lobes and corpus callosum. All the cases were pathologically diffuse large B cell lymphoma (DLBCL), 6 cases were the type of germinal center (GC) and 25 cases of non-GC type, after craniotomy operation and biopsy. Among 31 cases, 17 patients accepted the combined treatment, 3 patients underwent simple chemotherapy, 8 patients received simple radiotherapy, the other patients accepted support therapy. The median follow-up for surviving patients was 24 months. The 1-, 3-, and 5-year survival rates were 80.6%, 55.1%, and 36.4%, respectively. The median overall survival time in the combined treatment group was significantly longer than that in simply radiotherapy. There was no significant difference in OS between the groups with and without rituximab. ECOG PS≥2 and elevated serum LDH predicted inferior survival., Conclusion: The clinical manifectation of PCNSL is various and complicated, and for the time being there is no optimal treatment scheme. The overall survival time of the combined treatment is longer than that in simply radiotherapy. ECOG PS≥2 and elevated serum LDH often are poor prognostic factors.

This study focused on the nitrogen loss via runoff, change of nitrogen in different forms in surface water in paddy field, and grain yield, through further reduction of nitrogen fertilizer application rate under green manuring without basal dressing. Results showed that with 150 kg · hm(-2) inorganic N fertilizer input after return of green manure to soil, no basal dressing could not only sharply reduce N concentration in surface water and decrease 17.2% of N loss, but also increase 2.8% of grain yield in comparison with basal dressing. It was a worthwhile farming method that inorganic nitrogen fertilizer was not used for basal dressing but for topdressing after return of green ma- nure to soil in Taihu Area. However, the grain yield would decrease if the rate of topdressing nitro- gen was excessively reduced or increased. After all, it was feasible to realize harmonization of grain yield and environmental benefits in Taihu Area, with 133 kg · hm(-2) inorganic N fertilizer input after return of green manure to soil as well as no application of basal dressing, which could greatly reduce N fertilizer input and N loss as well as ensure rice yield.

Objective: To evaluate the effect of the viral load on the red blood cell parameters in chronic hepatitis B patients and its clinical significance., Methods: In the study, 373 chronic hepatitis B patients were recruited, including 123 alanine transaminase (ALT) normal patients (ALT<40 U/L),128 ALT greater than or equal to the upper limit of normal, and less than 2 times higher than the upper limit of normal patients(40 U/L ≤ALT<80 U/L), and 122 ALT greater than or equal to 2 times higher than the upper limit of normal patients (ALT≥80 U/L). The blood routine parameters were measured by automatic blood cell counter. The liver function parameters were measured by automatic biochemical analyzer, the hepatitis B virus loads were measured by quantitative PCR analyzer and the results were analyzed by covariance analysis., Results: In the ALT normal chronic hepatitis B patients group, the viral load had minor effects on the red blood cell parameters.But in the ALT abnormal chronic hepatitis B patients group, the viral load had a significant effect on the red blood cell parameters, and the effect was most manifest in the ALT≥ double upper limit of normal group. The specific performance was that with the viral load increasing, the red blood cell [low copies group (4.10±0.67)×10(12)/L,medium copies group (3.92±0.69)×10(12)/L,high copies group (3.54±0.90) ×10(12)/L], the hemoglobin[low copies group (129.66±21.12 ) g/L, medium copies group (126.23±23.38) g/L, high copies group (112.98±27.77) g/L], the hematocrit (low copies group 37.66±5.68, medium copies group 37.03±6.03, high copies group 33.34±8.15) decreased(P=0.006,0.007,0.010),the mean corpuscular volume [low copies group (92.17±6.53) fL, medium copies group (94.85±7.95) fL, high copies group (101.63±11.33) fL], the mean corpuscular hemoglobin [low copies group (31.70±2.22) pg, medium copies group (33.11±3.62) pg, high copies group (34.65±3.13) pg], the mean corpuscular hemoglobin concentration [low copies group (344.28±17.17) g/L, medium copies group (351.33±16.90) g/L, high copies group (358.12±15.67) g/L], and the red blood cell distribution width-standard deviation [low copies group (52.49±9.04) fL, medium copies group (56.96±7.19) fL, high copies group (61.23 ±7.23) fL] increased(P=0.000,0.000,0.002,0.000)., Conclusion: Observing the effect of the viral load on the red blood cell parameters in chronic hepatitis B patients can reflect the effect of hepatitis B virus on the immune response and liver function in the different pathological stages, providing theoretical support for the clinical antiviral treatment.

Objective: To observe the histological changes of juvenile porcine menisci in an in vitro organ culture system. It was hoped that the experiment can provide evidence for the study of menisci in an in vitro organ culture model., Methods: Eight juvenile swines of one month old were involves in the study. Thirty-two meniscal specimens with 8 mm in width were obtained from each meniscus in the two posterior extremities. The specimens were incubated in an in vitro organ culture model. At 0, 2, 4 and 6 weeks after culture, 8 specimens were observed. Hematoxylin eosin staining: the cell density of the inner 1/3 zone was measured. Safranin-O staining:the degree of staining in the inner zone was measured and semi-quantitative scores were obtained., Results: At 0, 2, 4 and 6 weeks, the cell density were (285.3 +/- 12.0)/HPF, (182.8 +/- 11.2)/HPF, (129.7+/- 9.9)/HPF, (92.3 +/- 9.3)/HPF respectively. Statistically significant differences were found between different time points (P < 0.05), Paired comparison showed statistical differences (P < 0.05). At 0, 2, 4 and 6 weeks, the semi-quantitative scores of Safranin-O staining were 2.0 +/- 0.0,1.5 +/- 0.5, 1.0 +/- 0.0, 0.5 +/- 0.5, statistically differences were found between different time points (P < 0.05). Paired comparison showed statistical differences (P < 0.05)., Conclusion: In the juvenile meniscus in vitro organ culture model, the cell density and viability diminished along with the cultural time. In vitro organ culture model is suitable for the study of menisci in short-term.

Effects of different concentrations of Cu2+, Cu2+ and Cd2+ combined pollution on the removal performance of COD in activated sludge system were investigated, and the ToxTell biosensor with activated sludge was constructed to determine the toxicity of Cu2+, Cu2+ and Cd2+ combined pollution. The results showed that there was no significant impact on the activated sludge process when Cu2+ concentration was lower than 10 mg x L(-1), and the addition of Cd2+ enhanced the inhibition of COD removal, and the maximum inhibition efficiency of COD reached at about 1.5 h. With the increase of aeration time, the COD removal efficiency increased slowly again. The toxicity measurement with ToxTell biosensor was close to the biological effects (inhibition efficiencies of COD), which showed that the ToxTell biosensor could be used well in the early warming determination of Cu2+ and Cd2+ in the activated sludge process.

The use of high frequency power to generate plasma at atmospheric pressure is a relatively new development. An apparatus of atmospheric pressure radio frequency dielectric barrier discharge was constructed. Plasma emission based measurement of electron density in discharge columns from Stark broadening Ar is discribed. The spacial profile of electron density was studied. In the middle of the discharge column, as the input power increases from 138 to 248 W, the electron density rises from 4.038 x 10(21) m(-3) to 4.75 x 10(21) m(-3).

Objective: To investigate the surgical techniques and results of open reduction and internal fixation for the treatment of Sanders type III, IV calcaneal fractures., Methods: From January 2004 to January 2010, 58 feet of Sanders type III, IV in 51 patients were treated with open reduction and plate fixation through L incision. There were 29 males and 22 females,the age ranged from 17 to 58 years with an average of 29.5 years old. The time between injury and operation ranged from 7 to 14 days (mean, 10 days). All the patients underwent systematic CT scan with coronal and horizontal images and sagittal reconstruction. The classification of the fractures by the Sanders scale showed that there were 26 feet of type III, 32 feet of type IV. The Böhler angle and Gissane angle were compared before and after operation. The clinical results were evaluated with the Maryland foot score: pain (45 scores), function (55 scores: distance walked 10 scores, stability 4, support 4, limp 4, shoes 10, stairs 4, terrain 4, cosmesis 10, motion 5)., Results: All 58 feet in 51 patients were followed up,and the duration ranged from 6 to 24 months,with an average of 13 months. The incidence of complications was 13.8% (8/58). Incision superficial necrosis in 2 feet,choronicity pain in 4 feet,subtalar joint arthrositis of advanced stage in 2 feet. According to Maryland foot score, the results were excellent in 23 feet, good in 27, fair in 5, poor in 3., Conclusion: The surgical techniques and results of internal fixation to fractures are related to anatomic features of calcaneus and their injury mechanism. It is an effective method for the treatment of calcaneal fractures with Sanders type III, IV.

Effects of nitrogen (N) management methods of paddy field on N export to environment and paddy N balance in Taihu lake region, China were studied. Field experiment including site-specific nitrogen management (SSNM), organic & chemical N fertilizer treatment (OCN), control released urea treatment (CRN), reduced chemical N treatment (RN) and farmer's N treatment (FN) were conducted at the Taihu lake region in 2008. N loss including runoff, leaching, ammonia volatilization and N2O were calculated, and the N balance was evaluated. Results showed the grain yield of SSNM, OCN, CRN and RN treatments was identical with FN treatment, while the total N rate reduced about 20%-40%, and N use efficiency (NUE) increased 14.5%-44%. N export of SSNM and CRN treatments decreased 52.8% and 45.4% in comparison with FN treatment. Under the same N input, N export of OCN treatment was lower than pure chemical N treatment (RN). N surplus was observed in FN treatment, while N deficit existed in SSNM treatments. CRN and SSNM treatments could increase NUE, reduce N export without sacrifice of yield and benefit, and could be as an economic and environment-friendly measure to intensify in Taihu lake region.

Objective: To study the clinical results of surgical treatment for Tile C type pelvis fractures with internal fixation by posterior approach., Methods: From January 2005 to June 2009, 12 patients with Tile C type pelvis fracture were treated by open reduction through posterior approach. There were 8 males and 4 females, with an average age of 39.5 years ranging from 25 to 58 years. The time from injury to operation was ranged from 7 to 10 days with an average of 9.5 days. All the patients were given X-ray, 3-D CT examinations before operation. The fracture were classified by Tile classification: Type C1 in 5 cases, Type C2 in 2 cases, Type C1 and Type C2 in 4 cases, Type C3 in 1 case. All the posterior rings were fixed by re-establishing steel board without anterior ring fixation after stabilization of body condition. All the patients were treated with skin traction for 3 weeks after operation., Results: All 12 patients were followed up for 6 months to 24 months with an average of 12.6 months. All the incisions healed well, and the fractures got union. No pelvic malunion, low back pain or leg length discrepancy was found. According to Majeed criteria for the evaluation of therapeutic effect, 10 patients were excellent, and 2 were good., Conclusion: In the management of the Tile C type pelvis fractures, a stable pelvis can be reconstructed by fixing posterior ring simply through the posterior approach, so that further sequelae can be reduced.

Objective: To explore the clinical features and the combined treatment modality of Hurthle cell thyroid tumor (HCT)., Methods: Twenty-eight cases of HCT treated between 2001 and 2009 were analyzed retrospectively., Results: The age of the patients ranged from 18 to 72 years (with a median of 46.5 years); 22 females and 6 males. The main symptoms were thyroid solitary node or mass (22 cases) and multiple nodule (6 cases), 2 cases with cervical lymph node metastasis. All of the patients underwent surgery, 11 cases with thyroid lobectomy, 11 cases with thyroid lobectomy plus isthmusectomy, 4 cases with subtotal thyroidectomy, and 2 cases with thyroid lobectomy plus isthmusectomy and combined with modified radical cervical lymph node dissection. Postoperative pathological examination showed that 22 cases were Hurthle cell adenomas and 6 cases were Hurthle cell carcinomas, 1 of them with cervical lymph node metastasis. Twenty-one patients with Hurthle cell adenomas were followed up for 6 months to 7.5 years (with a median of 45 months) and 6 patients with Hurthle cell carcinomas for 3 to 8 years (with a median of 54 months), with no recurrence and death case., Conclusions: HCT is a potential malignant neoplasm. There are some difficulties in the diagnosis of HCT by frozen section. Surgery is an effective treatment for HCT. L-Thyroxine can be used to inhibit TSH excretion.

The aim of this study was to investigate the clinical features of acquired hemophagocytic lymphohistiocytosis (HLH) complicated with hepatic dysfunction. 18 cases of acquired HLH were analyzed. The characteristics of hepatic dysfunction, the relationship between hepatic dysfunction and the cause, as well as prognosis of the acquired HLH were preliminarily analysed. The results indicated that characteristics of hepatic dysfunction in acquired HLH patients were hypoproteinemia, jaundice and increase of L-aspirate aminotransferase (AST) and lactate dehydrogenase (LDH) levels. The level of AST and direct bilirubin (DBil) in the non-malignancy associated hemophagocytic lymphohistiocytosis group were higher than that in malignancy-associated hemophagocytic lymphohistiocytosis group (p<0.05). And the increase of LDH and AST levels indicated poor prognosis (p<0.05). In conclusion, liver damage is a common organ functional disorder in patients with acquired HLH, which may be correlated to the cause and the prognosis of acquired HLH.

The objective of the present research was to study the potential of Vis-NIR (visible-near-infrared) high spectra for nondestructive determination of nitrate content in spinach leaves. Five different nitrogen treatments were carried out to achieve a wide range of nitrate content in spinach leaves. The leaf reflectance was measured between 350 to 2,500 nm with a 1 nm step with a leaf clip by ASD Fieldspec FR spectroradiometer, and the nitrate content was measured by spectrophotometric method (National Standard Method of P. R. China). Statistical models were developed using partial least squares (PLS) and principal component regression (PCR) analysis technique, different mathematical treatments for spectra processing such as smoothing, first and second derivative analysis, baseline correction, multiplicative scatter correction (MSC), and standard normal variate correction (SNV), and different wavelength ranges were compared to determine the best model. The dataset was separated into two parts: one used for calibration (n=43), and the other used for test (n=15). First, the model was calibrated and cross-validated with the calibration dataset, then the model was validated with the test dataset to test its prediction ability. The results showed that smoothing, first derivative and second derivative analysis can improve the prediction obviously, while other spectra pre-processing technique e. g. baseline correction, MSC and SNV technique can improve the prediction little. PCR analysis could get better modeling results than PLS analysis. The best model was obtained with the spectra first processed by smoothing then by first derivative change in the full range (350-2,500 nm). Test of the best PLS model and PCR model with an independent dataset exhibited a good agreement between the predicted and observed values, with the correlation coefficient of 0.94 for PLS model and 0.95 for PCR model, and the prediction RMSE was 128.2 mg x kg(-1) for PLS model and 120.8 mg x kg(-1) for PCR model, respectively. These results indicate that visible-NIR spectra technique is a feasible, nondestructive way to predict the nitrate content in spinach leaves.

Soil samples were collected from an experimental paddy field with long-term (26 years) fertilization in Taihu Lake region of Jiangsu Province to study the effects of different fertilization on the organic carbon distribution and stable carbon isotope natural abundance (delta 13C) in the soil profile, and on the humus composition. The results showed that long-term fertilization increased the organic carbon content in top soil significantly, and there was a significantly negative exponential correlation between soil organic carbon content and soil depth (P < 0.01). The organic carbon content in 10-30 cm soil layer under chemical fertilizations and in 20-40 cm soil layer under organic fertilizations was relatively stable. Soil delta 13C increased gradually with soil depth, its variation range being from -24% per thousand to -28 per thousand, and had a significantly negative linear correlation with soil organic carbon content (P < 0.05). In 0-20 cm soil layer, the delta 13C in treatments organic manure (M), M + NP, M + NPK, M + straw (R) + N, and R + N decreased significantly; while in 30-50 cm soil layer, the delta 13C in all organic fertilization treatments except R + N increased significantly. Tightly combined humus (humin) was the main humus composition in the soil, occupying 50% or more, and the rest were loosely and stably combined humus. Long-term fertilization increased the content of loosely combined humus and the ratio of humic acid (HA) to fulvic acid (FA).

Objective: To study the effect of inactivated and un-inactivated pharmaco-serum of diabetic rats fed with Chinese herbs Qianggubao decoction on the proliferation of osteoblast cells (OB)cultured in vitro., Methods: OB was isolated from the skull of newly born SD rats aged 1 to 2 days by means of Trypsin-collagenase digestion and identified by image analysis under inverted microscope, V-G collagen staining, ALP staining, calcification nod staining etc. After the OB was identified, in activated and un-inactivated pharmaco-serum of diabetic rats fed with Qianggubao decoction of ferent phase (rats were fed with medicine 3 days or 5 days after last fed with medicine 1 hour or 3 hours) and concentration (5%, 10%, 20%) were added to the OB and incubated. After determined times, the effects of the proliferation of osteoblasts were detected by MTT analysis., Results: There was significant difference between un-inactivated pharmaco-serum and inactivated pharmaco-serum on the proliferation of osteoblasts, and un-inactivated serum had stronger effects to improve the proliferation of osteoblasts (P < 0.01 or P < 0.05)., Conclusion: Un-inactivated and inactivation pharmaco-serum of diabetic rats fed with Chinese herbs Qianggubao decoction can influence the proliferation of, and the un-inactivated pharmaco-serum has stronger effects.

Objective: To investigate the optimum phase and dose of pharmaco-serum of diabetic rats fed with Qianggubao decoction ([Chinese characters: see text]) on the differentiation and mineralization of osteoblast (OB). METHODS (OB) was isolated from the skull of 10 newly born SD rats aged 1 to 2 days by means of Trypsin-collagenase digestion. After the OB was identified, different kinds of pharmaco-serum of diabetic rats fed with inactive Qianggubao decoction ([Chinese characters: see text]) of different phase (rats were fed with medicine three days or five days after last fed with medicine one hour or three hours) and concentration (5%, 10%, 20%) were added to the OB and incubated. After 7 days and 18 days of culture,the effects of the differentiation and mineralization of osteoblast were detected., Results: The secretion of ALP and formation of mineralized nodules of osteoblast in the different doses of pharmaco-serum groups were almost the same as that of normal control group, but were superior to that in the model control group. And the group with concentration of 20% pharmaco-serum was the best in the secretion of ALP and formation of mineralized nodules of osteoblast. As to the phases of pharmaco-serum, the best one on the differentiation and mineralization of osteoblast was the serums from diabetic rat-model fed with Qianggubao decoction ([Chinese characters: see text]) three days or five days, after one hour of last fed with medicine., Conclusion: The pharmaco-serum of diabetic rats fed with Qianggubao decoction ([Chinese characters: see text]) can promote the differentiation and mineralization of osteoblast. Allow for time and the cost of experiment,we presume that pharmaco-serum of diabetic rats fed with Qianggubao decoction ([Chinese characters: see text]) three days, after one hour of last fed, with concentration of 20% and not-inactivation is the optimum on the differentiation and mineralization of osteoblast.

Based on high spatial resolution remote sensing map (1 m) and sampling with a stratified design on different site types, the effects of fine-scale land use patterns in villages on top soil (0-30 cm) organic carbon (OC), total nitrogen (TN) and total phosphorus (TP) within and across the densely populated hilly landscapes, i. e., Sichuan Hilly Region (SIHR; Jintang County, Sichuan Province), Subtropical Hilly Region (SUHR; Yiyang County, Hunan Province), and Tropical Hilly Region (THR; Dianbai County, Guangdong Province), were investigated. The results showed that soil OC density was decreased in the order of SUHR (2.72 +/- 0.76 kg x m(-2)) > THR (2.65 +/- 0.73 kg x m(-2)) > SIHR (2.15 +/- 0.57 kg x m(-2)), TN density was in the order of SUHR (0.28 +/- 0.06 kg x m(-2)) > SIHR (0.27 +/- 0.06 kg x m(-2) > THR (0.21 +/- 0.06 kg x m(-2)), and TP density was in the order of SIHR (0.19 +/- 0.04 kg x m(-2)) > SUHR (0.11 +/- 0.03 kg x m(-2)) > THR (0.08 +/- 0.04 kg x m(-2)). The fine-scale landscape units (ecotopes) with the highest soil OC, TN and/or TP stocks were rainfed annual crops in SIHR, paddy rice in SUHR, and open canopy trees and brush in THR, respectively. In all hilly regions, paddy and forest land use classes had the highest soil OC and TN density, while mined areas had the lowest soil OC and TN density, with the distribution of TP density showing a more complicated pattern than that of OC and TN. Ecotope level analysis could reflect the soil organic carbon, nitrogen and phosphorus distribution in densely populated village landscape of hilly regions more comprehensively than land use or land cover analysis.

By the method of consecutive extraction, this paper studied the contents and vertical distribution of soil fluorine (F) forms in North Anhui, with their relations to the soil physical and chemical properties analyzed. The results showed that the soil total F (T-F) content in North Anhui was ranged from 265.8 mg . kg(-1) to 612.8 mg . kg(-1), with an average of 423.7 mg . kg(-1), and decreased in the sequence of vegetable soil > fluvo-aquic soil > paddy soil > shajiang black soil > yellow brown soil. Among the T-F, residual F (Res-F) was the main form, occupying > 95% of total F, followed by water soluble F (Ws-F), being about 1.5% of the total, and organic-F (Or-F), Fe and Mn oxide-F (Fe/Mn-F) and exchangeable-F (Ex-F) only had very small amount. The Ws-F content in test soils ranged from 1.35 mg . kg(-1) to 17.98 mg . kg(-1), with a mean value of 6.62 mg . kg(-1). Vegetable soil, fluvo-aquic soil and shajiang black soil had a relatively higher content of Ws-F, while yellow brown soil was in adverse. Soil pH and the contents of soil organic matter, total and available phosphorus, and physical clay were the main factors affecting the contents of various F forms. Soil Ws-F was significantly positively correlated with soil pH and soil total and available phosphorus, soil Ex-F was significantly positively correlated with soil clay ( < 0.01 mm and <0.001 mm), soil Fe/Mn-F was significantly positively correlated with soil total phosphorus, and soil Or-F had a significant positive correlation with soil organic matter. Soil Ws-F content also had a close connection to the parent material. The soil developed from shallow lacustrine and marsh sediments usually had the highest Ws-F content, followed by those developed from Huang River alluvial deposit, Q3 loess, Huaihe River alluvial deposit, and light-texture yellow brown soil, with the mean Ws-F content being 9.05, 8.12, 2.97, 2.05 and 1.91 mg . kg(-1), respectively. The contents of soil Or-F and Fe/Mn-F decreased with increasing soil depth, and those of T-F and Ws-F in vegetable soil were higher in upper than in deeper soil layers.

The adsorption of acid orange II onto modified peat-resin particles was examined in aqueous solution in a batch system. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. The pseudo-first-order, pseudo-second-order kinetic and the intraparticle diffusion models were used to describe the kinetic data. The results showed that both Langmuir and Freundlich adsorption models could be used to describe the adsorption of acid orange II onto modified peat-resin particles. The maximum adsorption capacity was 71.43 mg x g(-1). The data analysis indicated that the intraparticle diffusion model could fit the results of kinetic experiment well. The adsorption rate of acid orange II onto modified peat-resin particles is affected by the initial dye concentrations, sizes and doses of modified peat-resin particles and agitation rates. The surface of modified peat-resin particle is the major adsorption area.

Soil samples of current paddy soils, ancient paddy soil/ancient dry land soil, and bottom soils were collected from two sites in Chuodunshan Site of Majiabang Culture (about 6,000a). 15 polycyclic aromatic hydrocarbons (PAHs) were analyzed with HPLC, and their possible sources were identified. The sum of 15 PAHs was 202.9microg x kg(-1) and 207.7microg x kg(-1) in the surface soils from Site A and Site B respectively, which were mainly deposited from atmosphere. In ancient paddy soil from Site A, the total PAHs concentration sharply decreased to 56.0microg x kg(-1), but was still higher than those in ancient dry land soil and bottom soils with the sum of 32.0 approximately 36.9microg x kg(-1). In ancient paddy soil, the concentrations of 2-ring and 3-ring PAHs took a larger portion of 63 percents to the total PAHs, and naphthalene and phenanthrene were the most abundant compounds, while PAHs of more than 4 rings took a small part. The ratios of phenanthrene anthracene and benzo(a) anthracene chrysene and 13C-NMR spectrum of soil organic matter showed that PAHs in ancient paddy soil mainly originated from rice straw burning, biogenesis under reducing conditions may be another source.

The p-phendioxyl base in the spacer of gemini surfactant C11pPHCNa emits fluorescence under exciting. When the gemini concentration is over 0.45 mmol x L(-1), the topological structure of the excitation spectra yields various changes resulting in them being significantly different from the corresponding absorption spectra. As the aromatic base in the spacer of C11pPHCNa obviously quenches the fluorescence of pyrene that is as additional probe, it is hardly to determine the average micelle aggregation number by the usual method of quenching pyrene. In the present paper, using the property of methylviologen (MV2+) effectively quenching the fluorescence of C11pPHCNa, the authors established the method to determine the average aggregation number N of C11pPHCNa micelle. For individual C11pPHCNa micelle, N was determined to be 20.6 at c=2 mmol L(-1), while the average aggregation number of C11pPHCNa/C12-2-E1-C12 x 2Br mixed micelle in the aqueous solution with a total concentration of 2 mmol x L(-1) and C11pPHCNa of mole fraction 0.3 in the bulk was obtained to be 11.8.

Objective: To prepare a new dosage formulation of activated carbon nanoparticles adsorbing mitomycin C (MMC-ACNP) and evaluate the beneficial effects of intraperitoneally applied MMC-ACNP as a drug delivery system for lymphatic targeting in preventing metastasis and recurrence of gastric cancer., Methods: MMC-ACNP was prepared. Acute toxicity after its intraperitoneal administration was evaluated. An experiment on nude mice model with transplanted human gastric cancer in 6 groups was completed to assess the effects of drugs on intra-abdominal carcinomatosis., Results: The LD50 of MMC-ACNP was 46.80 mg/kg (in terms of MMC) while that of MMC aqueous solution was 9.33 mg/kg. The toxicity of MMC-ACNP was much less than that of the solution form. MMC-ACNP was superior to MMC aqueous solution in controlling carcinomatosis and tumor growth by intraperitoneal administration. Despite the high dose of MMC, leukopenia and thrombocytopenia were not observed in the MMC-ACNP treated group. Fine activated carbon particles adsorbing MMC entered the nuclei of tumor cells, so that the effects of the anticancer drug were reinforced., Conclusion: MMC-ACNP gives a good promise of clinical use due to its advantages such as high selectivity and low toxicity.

Objective: To develop a questionnaire to evaluate the cooperation of adolescent orthodontic patients., Methods: 182 orthodontic patients (9 - 15 years old, 78 boys and 104 girls) with fixed appliance were selected in Dalian. A questionnaire was developed according to the past research and 4 hypotheses., Results: The scale is made up of 25 items and 4 factors. The reliability of this scale was confirmed (the reliability coefficient > 0.9 and Cronbach alpha coefficient > 0.7)., Conclusion: The questionnaire may be used to evaluate the cooperation of orthodontic patients.

An investigation on the effect of RU486 on isolated ovicluct smooth muscle contraction of pseudopregant rabbits was carried out by using the mechanical-electrical transducer of Galson recorder. The results showed that: (1) RU486 acted directly on the oviduct smooth muscle by increasing contractile frequency, without changing tension and amplitude. This effect is similar to that found in the in vivo experiment. (2) RU486 partially inhibited Ca(2+)-induced smooth muscle contraction and also showed significant synergistic effect of Verapamil and antagonistic effect of NE on muscle contractility. However, RU486 is unable to exert any effect on Forskolin-stimulated contraction. Thus it appears that the RU486 effect on oviduct smooth muscle contraction is a result of affecting intracellular free calium, due possibly to interference of Ca2+ influx and/or endoplasmic reticulum Ca2+ release and Ca(2+)-Ip3 transducing mechanism.

Effects of methylflavonolamine (MFA) on arrhythmias induced by myocardial reperfusion were studied with rat hearts in situ and in vitro. In pentobarbital-anesthetized rats, MFA (20 mg.kg-1, i.v.) pretreatment reduced the incidence of reperfusion-induced ventricular fibrillation after left descending coronary artery ligation (15 min) and reperfusion (3 min) (28.6% vs 85.7% in control, P less than 0.05). Malondialdehyde (MDA) production (85 +/- 9 nmol/g wet wt) was inhibited in myocardium from the reperfused area in comparison with control (133 +/- 15 nmol/g wet wt). In isolated rat hearts with local ischemia (15 min) and reperfusion (1 min), MFA 5 mumol.L-1 (perfused 10 min prior to coronary artery ligation) prevented reperfusion-induced arrhythmias (0% vs 85.7% in control, P less than 0.01). In myocardium from the reperfused area, superoxide dismutase (SOD) and catalase (Cat) activity was increased and xanthine oxidase (XOD) activity, MDA production and nonesterified fatty acids (NEFA) contents were decreased. The results show that MFA prevents reperfusion-induced arrhythmia by inhibiting lipid peroxidation and regulating the metabolism of NEFA.