Electrostatic wrapping of eupatorium-based botanical herbicide with chitosan derivatives for controlled release.

To avoid the negative effects of chemical herbicides and prepare herbicide with long-term efficacy, the active ingredients of eupatorium adenophorum spreng (AIEAS, negatively charged) were used as a botanical herbicide, and based on electrostatic attraction, the self-assembled hydroxyl isopropyl chitosan (HPCTS, positively charged) and carboxymethyl chitosan (CMC, with good water solubility) were successfully employed as degradable and water-soluble carrier for AIEAS to realize its controlled release. The release of AIEAS from the chitosan carrier in water could be divided into two stages. In the first stage, a fast release of AIEAS was detected and the total amount of the released AIEAS reached 41.5 %, while the release rate effectively slowed down in the second stage, indicating that good balance between fast control of weeds and long-term efficacy was achieved through this controlled delivery system. The release kinetics of AIEAS during the whole release process showed good fit to the Ritger-Peppas model with Fickian diffusion as the dominant release mechanism. Moreover, it found that the released AIEAS from chitosan carrier showed fine herbicidal effect on barnyard grass.

Pharmacologic Effect of Miao Medicine Illicium simonsii Maxim. on Collagen-Induced Arthritis in Rats.

OBJECTIVES: To study the pharmacologic effect and mechanism of action of Miao medicine Illicium simonsii Maxim. (ISM) in treating rheumatoid arthritis. METHODS: Sixty rats were randomly divided to six groups: normal control (normal), collagen-induced arthritis (CIA) model (model), CIA + tripterygium glycosides (TG), CIA + ISM high dose oral (ISM-H), CIA + ISM low-dose oral (ISM-L), and CIA + ISM topical application (ISM-T). The treatment doses were selected based on published reports and folk medicine practice. The outcome measurements included paw swelling, joint pathology, organ index, blood count, T helper 17 (Th17) cell count, and interleukin-6 (IL-6) level. RESULTS: Compared to the CIA model group, all treatment groups showed a significant reduction in paw swelling, blood vessel pathology, Th17 cell count, and IL-6 levels (p < 0.05 or p < 0.01). All treatment groups showed alleviated foot swelling and lower total number of white blood cells, and these effects were observed earlier with oral ISM than topical ISM. The effect of ISM was weaker than that of TG. In addition, less organ damage was observed with topical ISM than oral ISM but better than TG. CONCLUSIONS: These results suggest that, by downregulating Th17 cells, ISM inhibits the production of Il-6, thereby alleviating the proliferation of endothelial and rheumatoid-like cells and leukocytosis in CIA rats, ultimately eliminating foot swelling.

Long-term effects of nitrogen fertilization on aggregation and localization of carbon, nitrogen and microbial activities in soil.

Long-term nitrogen (N) fertilization affects soil aggregation and localizations of soil organic carbon (SOC), N and microbial parameters within aggregates. The mechanisms of these N effects are poorly understood. We studied these processes in a loamy soil from a 23-year repeated N addition field experiment under a rice-barley rotation. Nitrogen fertilization increased plant productivity and the portion of large macroaggregates (>2mm). However, SOC contents in macro- and micro-aggregates remained constant despite an N-induced increase of 27% in root C input into soil. Therefore, N fertilization accelerated SOC turnover. Nitrogen addition increased total N (TN) content in bulk soil and two macroaggregates (>2, and 1-2mm), but not in microaggregates (<0.25mm). Also, N fertilization increased the phospholipid fatty acids (PLFAs) contents of fungi in the large macroaggregates, but not in the microaggregates. In contrast, the effect of N addition on contents of bacterial and total microbial PLFAs was not apparent. Nitrogen fertilization increased N-acetyl-ß-D-glucosaminidase (NAG) activities in the two larger macroaggregate size classes (>2, and 1-2mm), but not in the aggregates (<1mm). In both control and N fertilization, the large macroaggregates localized more TN, microbial PLFAs, and NAG activities than the microaggregates. In conclusion, long-term N fertilization not only directly promotes soil N resource but also indirectly improves soil structure by forming large macroaggregates, accelerates SOC turnover, and shiftes localization of microorganisms to the macroaggregates.

Effects of biochar on soil microbial biomass after four years of consecutive application in the north China Plain.

The long term effect of biochar application on soil microbial biomass is not well understood. We measured soil microbial biomass carbon (MBC) and nitrogen (MBN) in a field experiment during a winter wheat growing season after four consecutive years of no (CK), 4.5 (B4.5) and 9.0 t biochar ha(-1) yr(-1) (B9.0) applied. For comparison, a treatment with wheat straw residue incorporation (SR) was also included. Results showed that biochar application increased soil MBC significantly compared to the CK treatment, and that the effect size increased with biochar application rate. The B9.0 treatment showed the same effect on MBC as the SR treatment. Treatments effects on soil MBN were less strong than for MBC. The microbial biomass C∶N ratio was significantly increased by biochar. Biochar might decrease the fraction of biomass N mineralized (KN), which would make the soil MBN for biochar treatments underestimated, and microbial biomass C∶N ratios overestimated. Seasonal fluctuation in MBC was less for biochar amended soils than for CK and SR treatments, suggesting that biochar induced a less extreme environment for microorganisms throughout the season. There was a significant positive correlation between MBC and soil water content (SWC), but there was no significant correlation between MBC and soil temperature. Biochar amendments may therefore reduce temporal variability in environmental conditions for microbial growth in this system thereby reducing temporal fluctuations in C and N dynamics.

[Experimental observation of SIVmac239 Chinese rhesus monkey model at sub-acute phase of AIDS].

OBJECTIVE: To observe T lymphocyte subsets and indicators of changes in viral load in sub-acute period in Chinese rhesus monkey model of AIDS SIVmac239. To explore Virology related index variation in sub-acute period of the Chinese rhesus monkey model of AIDS. METHOD: To replicate Chinese rhesus monkey model of AIDS, healthy Chinese rhesus monkey was inoculated with SIVmac239 viral strain. To observe changes in T lymphocyte subsets indexes and viral load after infection with the simian immunodeficiency virus (SIV) in sub-acute period on an animal model. The clinical symptoms of the animal model was recorded simultaneously. RESULT: During the 10 weeks after SIV acute infection, body weight and BMI index were relatively stable, the difference was not significant at all time points. Twelve monkeys were tested SIV positive by real-time PCR after three days of infection. On the 7th day after infection, 15 monkeys were tested SIV positive. Viral load increased rapidly, but reached a peak on the 10th-14th day after infection, then showed a level of volatility decline. T lymphocyte subsets showed significant changes, among them, CD3% and CD3 counts fluctuated upward trend and reached to the highest level in two weeks after infection; of CD4% and CD4 count changes were not synchronized, CD4% declined trend while the CD4 count was an increasing trend after the infection; of CD8% and CD8 counts fluctuate upward trend, and reached to a highest level in two weeks after infection ;the ratio of CD4/CD8 and the counts of CD4CD28 T cells decreased significantly in two weeks after infection; the former followed by a slow decline, the latter followed by a rapid rise. Three mouths after the infection 3 monkeys showed significant clinical symptoms. One of the rhesus monkeys had symptoms of diarrhea and two of them had reduced food intake. CONCLUSION: This experiments established standardization of Chinese Rhesus monkeys used in the research of AIDS and provide a detailed contents in the changes of sub-acute phase.

[Spatial discharge characteristics and total load control of non-point source pollutants based on the catchment scale].

Agricultural non-point source pollution is one of the major causes of water quality deterioration. Based on the analysis of the spatial discharge characteristics and intensity of major pollutants from the agricultural pollution source, the establishment of spatial management subzones for controlling agricultural non-point pollution and a design of a plan for total load control of pollutants from each subzone is an important way to improve the efficiency of control measures. In this paper the Four Lake basin in Hubei Province is adopted as the research case region and a systematic research of the control countermeasures of agricultural non-point pollution based on the catchment scale is carried out. The results shows that in the Four Lake basin, the COD, total nitrogen, total phosphorus and ammonia nitrogen load of the water environment are mainly caused by agricultural non-point pollution. These four kinds of non-point source pollutants respectively account for 67.6%, 82.2%, 84.7% and 50.9% of the total pollutant discharge amount in the basin. The analysis of the spatial discharge characteristics of non-point source pollutants in the Four Lake basin shows that the major contributor source regions of non-point source pollutant in the basin are the four counties, including Honghu, Jianli, Qianjiang and Shayang where the aquatic and livestock production are relatively developed. According to the spatial discharge characteristics of the pollutants and the evaluation of the discharge intensity of pollutants, the Four Lake basin is divided into three agricultural non-point pollution management subzones, which including Changhu upstream aquatic and livestock production pollution control subzone, Four-lake trunk canal rural non-point source pollution control subzone and Honghu aquatic production pollution control subzone. Specific pollution control measures are put forward for each subzone. With a comprehensive consideration of the water quality amelioration and the allowable discharge of pollutants, a total load control solution is designed for the three non-point pollution management subzones, so as to fulfill the requirements of all indices of the monitoring sites and the requirements for the allowable discharge of pollutants of the water. Among the major pollutants, the major COD reduction area includes the Four-lake trunk canal subzone and the Honghu Lake subzone, which respectively account for 43% and 42% of the total COD reduction amount; the major ammonia nitrogen reduction area includes the Four-lake trunk canal subzone, accounting for 66% of the total ammonia nitrogen reduction amount; the major total nitrogen reduction area covers the Four-lake trunk canal subzone and the Honghu Lake subzone, accounting for 42% and 31% of the total nitrogen reduction amount in the basin respectively; the major total phosphorus reduction area is the Four-lake trunk canal subzone, accounting for 53% of the total phosphorus reduction amount in the basin.

[Effects of biochar amendment on cropland soil bulk density, cation exchange capacity, and particulate organic matter content in the North China Plain].

A 3-year field experiment with randomized block design was conducted to study the effects of biochar amendment on the soil bulk density, cation exchange capacity (CEC), and particulate organic matter C (POM-C) and N (POM-N) contents in a high-yielding cropland in the North China Plain. Four treatments were installed, i.e., chemical NPK (CK), chemical NPK plus 2250 kg x hm(-2) of biochar (C1), chemical NPK plus 4500 kg x hm(-2) of biochar (C2), and 750 kg x hm(-2) of biochar-based slow release fertilizer (CN). Comparing with CK, treatments C1 and C2 significantly decreased the bulk density of 0-7.5 cm soil layer by 4.5% and 6.0%, respectively, and the treatments with biochar amendment increased the CEC in 0-15 cm soil layer, with an increment of 24.5% in treatment C2. Biochar amendment also increased the C (POM-C) and N (POM-N) contents in 0-7.5 cm soil layer, e.g., the POM-C and N contents in treatment C1 and C2 were 250% and 85%, and 260% and 120% higher than those of the CK, respectively. After three years of biochar amendment, the soil had obvious improvement in its physical and chemical properties, and played more active roles in soil carbon sequestration and greenhouse gases emission reduction.

Leaching behavior of nitrogen in a long-term experiment on rice under different N management systems.

The leaching behavior of nitrogen was studied in single rice paddy production ecosystems in Tsukuba, Japan after 75 years of consistent fertilization regimes (no fertilizer, ammonium sulfate, a combination of composted rice straw with soybean cake, and fresh clover). During the 75-year period, management was unchanged with respect to rice planting density, irrigation, and net N fertilization for each field to which an N-source was added. Percolation water was collected, from May 2001 to April 2002, using porous suction cups installed in the fields at depths of 15, 40, and 60 cm. All water samples were taken to the laboratory for the measurement of both NH(4) ( + )-N and NO(3) ( - )-N concentrations using a continuous-flow nitrogen analyzer. The result indicated that there were significant differences in N leaching losses between treatments during the rice growing season. Total N leaching was significantly lower with the application of composted rice straw plus soybean cake (0.58 kg N ha( - 1)) than with ammonium sulfate (2.41 kg N ha( - 1)), which resulted in N leaching at a similar level to that with the fresh clover treatment (no significant difference). The majority of this N leaching was not due to NO(3) ( - )-N loss, but to that of NH(4) ( + )-N. The mean N leaching for all fertilizer treatments during the entire rice growing season was 1.58 kg N ha( - 1). Composted rice straw plus soybean cake produced leaching losses which were 65-75% lower than those with the application of fresh clover and ammonium sulfate. N accumulation resulting from nitrification in the fallow season could be a key source of nitrate-N leaching when fields become re-flooded before rice transplanting in the following year; particular attention should be paid to this phenomenon.

[Effect of acupuncture treatment of relieving depression and regulating mind on insomnia accompanied with depressive disorders].

OBJECTIVE: To compare the therapeutic effects of insomnia accompanied with depressive disorders treated by acupuncture of relieving depression and regulating mind and oral administration of Trazodone. METHODS: Sixty-five cases were randomly divided into a acupuncture group (33 cases) and western medication group (32 cases). In acupuncture group, Shenmen (HT 7), Baihui (CV 20), Hegu (LI 4) and Taichong (LR 3) were selected. In western medication group, Trazodone was applied with oral administration for 4 weeks. The curative effect comparison was carried on by Pittsburgh Sleep Quality Index (PSQI), Self-Rating Depression Scale (SDS), and Side Effect Rating Scale (SERS) of Asberg. RESULTS: The cured and markedly effective rate of 72.7% (24/33)in acupuncture group was superior to that of 46.8% (15/32) in western medication group; after treatment, the scores of all items and the total cumulative scores of PSQI and SDS of both groups were reduced (P < 0.01, P < 0.05), of which, the sleep quality and daytime function evaluation in acupuncture group reduced more obviously than those in western medication group (both P < 0.05); the SERS scores of Asberg in western medication group were higher than those in acupuncture group. CONCLUSION: Acupuncture treatment of relieving depression and regulating mind is superior to Trazodone with oral administration for sleep quality and daytime function, with milder adverse reactions.

[Accumulation of soil inorganic nitrogen in mono-harvesting farmlands in northeast China in late autumn].

The study showed that in northeast China, the farmlands with a mono-harvesting agricultural system had a low accumulation of soil inorganic nitrogen after harvest. In late autumn, there was an interval of about 20-30 days when the temperature and humidity were appropriate to soil N mineralization, but the mineralized nitrogen could not be used by crops in this non-growing season. The accumulation of inorganic nitrogen in upland soil reached a high level before freezing. Its inorganic nitrogen content in 1 m depth soil was 99.9 kg x hm(-2) in the treatment of commercial fertilizers (N 150 kg x hm(-2); P 16.4 kg x hm(-2); K 62.3 kg x hm(-2))and 145.4 kg x hm(-2) in the treatment of commercial fertilizers plus manure (pig manure by a reutilization of 80% product). While in rice field, its inorganic nitrogen content was relatively low before freezing. The reason might be that the soil permeability was not as good as that in upland for its long-term water-logging, and its insufficient aeration would be favorable to denitrification which induces the inorganic nitrogen loss via N2O emission.

[Advances in studies on accumulation and leaching of nitrate in farming soil].

Nitrate leaching in farming soil is the main reason resulting in ground water pollution of nitrate. The main factors, which can affect nitrate accumulation and leaching greatly, include fertilization, precipitation, irrigation, soil characteristics, and cultivation system. Superfluous nitrogen in soil caused either by using chemical fertilizer and manure solely or compost will result in nitrate accumulation. Cultivation and plow systems also can affect the process of nitrate accumulating and leaching. Down flows due to irrigation or precipitation are the necessary condition and carrier for transference and leaching of accumulated nitrate in soil. Great pores are the main channels for down flows. These factors always work corporately. Mathematical model, which has been developed quickly and used widely, may be a good method to study and predict nitrate leaching in farming land.