Effect of biochars on the immobilization and form of Cadmium (Cd) in simulated Cd deposition of iron rich soils.

Atmospheric deposition of Cd poses a serious threat to ecosystem security. Biochar is widely used for polluted soil remediation, however, whether biochar already applied to the soil can reduce the hazards of newly deposited Cd remains to be studied. Thus, an indoor cultural experiment and static adsorption method were conducted to study the isothermal and kinetic adsorption processes of three types of biochar (rice husk, rubber wood, and tobacco stem biochars) on Cd in iron rich soils and the effect of biochar on the morphological distribution of Cd in the soil and the soil pH. The results showed that the soil with biochar in our study could quickly fix "the new deposited Cd" in the soil in 3 h with the maximum adsorption capacity in rubber wood biochar-treated sample (3227.34 mg/kg）. The addition of all three biochar treatments significantly increased the soil pH and reduced the soil exchange state Cd content, with a 13.69-17.32% increase in the pH and a 13.22-54.39% reduction in the exchange state Cd content when contrasted with the control, which could promote those Cd converting into unavailable Cd (carbonate-bound form Cd, Fe-Mn oxide-bound form Cd, or residual form Cd) for crops. In summary, the addition of three kinds of biochar treatments could effectively reduce the ecological and environmental risk of soil that was contaminated by Cd and could provide a reliable theoretical basis for the effect of biochar on the improvement of the quality of soil that is contaminated by heavy metals.

Mercury in rice paddy fields and how does some agricultural activities affect the translocation and transformation of mercury - A critical review.

Human exposure to methylmercury (MeHg) through rice consumption is raising health concerns. It has long been recognized that MeHg found in rice grain predominately originated from paddy soil. Anaerobic conditions in paddy fields promote Hg methylation, potentially leading to high MeHg concentrations in rice grain. Understanding the transformation and migration of Hg in the rice paddy system, as well as the effects of farming activities, are keys to assessing risks and developing potential mitigation strategies. Therefore, this review examines the current state of knowledge on: 1) sources of Hg in paddy fields; 2) how MeHg and inorganic Hg (IHg) are transformed (including abiotic and biotic processes); 3) how IHg and MeHg enter and translocate in rice plants; and 4) how regular farming activities (including the application of fertilizer, cultivation methods, choice of cultivar), affect Hg cycling in the paddy field system. Current issues and controversies on Hg transformation and migration in the paddy field system are also discussed.

Barrier Properties and Characterizations of Poly(lactic Acid)/ZnO Nanocomposites.

This study aimed to reinforce the barrier performance (i.e., oxygen-gas and water-vapor permeability) of poly(lactic acid) (PLA)-based films. Acetyltributylcitrate and zinc oxide nanoparticle (nano-ZnO), serving as plasticizer and nanofiller, respectively, were blended into a PLA matrix through a solvent-volatilizing method. The structural, morphological, thermal, and mechanical performances were then studied. Scanning electron microscopic images showed a significant dispersion of nano-ZnO in PLA ternary systems with low nano-ZnO content. The interaction between PLA matrix and ZnO nanoparticles was further analyzed by Fourier-transform infrared spectroscopy. Wide-angle X-ray scattering spectroscopy demonstrated high compatibility between PLA matrix and ZnO nanoparticles. Mechanical property studies revealed good tensile strength and low flexibility. Differential scanning calorimetry curves proved that an amorphous structure mostly existed in PLA ternary systems. The improvements in barrier property and tensile strength indicated that the PLA/nano-ZnO composite films could be used for food packaging application.

The Performance Changes and Migration Behavior of PLA/Nano-TiO2 Composite Film by High-Pressure Treatment in Ethanol Solution.

To study the relationship between performance changes and nanoparticles migration of the composite film at different migration stages, the poly (lactic acid) (PLA)/nano-TiO2 composite film treated by high pressure was immersed in 50% (v/v) ethanol solution for 45 days at 40 °C, and the film characteristics and migration behavior were analyzed. The results showed that the migration of the composite film with the highest loading of nano-TiO2 (20 wt. %) in alcoholic food simulated solution was far less than 10 mg/kg during the 45-day migration process. Although with the increase of migration time, the micro-morphology of composite film became rougher, the crystallinity decreased and the gas permeability increased, but the internal crystal structure of the composite film remained basically unchanged. The PLA/nano-TiO2 composite films treated by high pressure treatment were relatively stable, and had good performance and migration behavior in alcoholic food simulated solution, the nanocomposite film after high pressure treatment could be used to reduce nano-TiO2 particle migration and subsequently reduce human exposure as the packaging film for the packaging of alcoholic food, which provide a theoretical basis for the applications of high pressure treatment of PLA/nano-TiO2 composite films in food packaging material and broaden its application prospects.

Mercury in rice (Oryza sativa L.) and rice-paddy soils under long-term fertilizer and organic amendment.

High levels of mercury (Hg), especially methylmercury (MeHg), in rice is of concern due to its potential of entering food chain and the high toxicity to human. The level and form of Hg in rice could be influenced by fertilizers and other soil amendments. Studies were conducted to evaluate the effect of 24 years application of chemical fertilizers and organic amendments on total Hg (THg) and MeHg and their translocation in soil, plants, and rice grain. All treatments led to significantly higher concentrations of MeHg in grain than those from the untreated control. Of nine treatments tested, chemical fertilizers combining with returning rice straw (NPK1+S) led to highest MeHg concentration in grain and soil; while the nitrogen and potassium (NK) treatment led to significantly higher THg in grain. Concentrations of soil MeHg were significantly correlated with THg in soil (r = 0.59***) and MeHg in grain (r = 0.48***). Calcium superphosphate negatively affected plant bioavailability of soil Hg. MeHg concentration in rice was heavily influenced by soil Hg levels. Phosphorus fertilizer was a main source contributing to soil THg, while returning rice straw to the field contributed significantly to MeHg in soil and rice grain. As a result, caution should be exercised in soil treatment or when utilizing Hg-contaminated soils to produce rice for human consumption. Strategic management of rice straw and phosphorus fertilizer could be effective strategies of lowering soil Hg, which would ultimately lower MeHg in rice and the risk of Hg entering food chain.

Reducing soil erosion and nutrient loss on sloping land under crop-mulberry management system.

Sloping croplands could result in soil erosion, which leads to non-point source pollution of the aquatic system in the Three Gorges Reservoir Region. Mulberry, a commonly grown cash plant in the region, is traditionally planted in contour hedgerows as an effective management practice to control soil erosion and non-point source pollution. In this field study, surface runoff and soil N and P loss on sloping land under crop-mulberry management were investigated. The experiments consisted of six crop-mulberry treatments: Control (no mulberry hedgerow with mustard-corn rotation); T1 (two-row contour mulberry with mustard-corn rotation); T2 (three-row contour mulberry with mustard-corn rotation); T3 (border mulberry and one-row contour mulberry with mustard-corn rotation); T4 (border mulberry with mustard-corn rotation); T5 (two-row longitudinal mulberry with mustard). The results indicated that crop-mulberry systems could effectively reduce surface runoff and soil and nutrient loss from arable slope land. Surface runoff from T1 (342.13 m(3) hm(-2)), T2 (260.6 m(3) hm(-2)), T3 (113.13 m(3) hm(-2)), T4 (114 m(3) hm(-2)), and T5 (129 m(3) hm(-2)) was reduced by 15.4, 35.6, 72.0, 71.8, and 68.1%, respectively, while soil loss from T1 (0.21 t hm(-2)), T2 (0.13 t hm(-2)), T3 (0.08 t hm(-2)), T4 (0.11 t hm(-2)), and T5 (0.12 t hm(-2)) was reduced by 52.3, 70.5, 81.8, 75.0, and 72.7%, respectively, as compared with the control. Crop-mulberry ecosystem would also elevate soil N by 22.3% and soil P by 57.4%, and soil nutrient status was contour-line dependent.

[Clinical observation on distinctive water-medicine cup therapy for treatment of cervical spondylopathy of cervical type].

OBJECTIVE: To use distinctive water-medicine cup therapy for treatment of cervical spondylopathy of cervical type as a sample to provide a more effective cupping method for clinic. METHODS: One hundred and forty cases were randomly divided into a medicine cup group (n = 47), a water cup group (n = 47) and a empty cup group (n = 46). The medicine cup group were treated by cupping therapy with a self-made medicine cup with 45 degrees C Chinese herb solution; the water cup group were treated with a cup with 45 degrees C water, and the empty cup group with a cup with nothing. Clinical symptoms and signs were observed for comparison of therapeutic effects. RESULTS: Clinically cured was 39 cases, and markedly effective was 8 cases in the medicine cup group; 20 cases were clinically cured, 22 cases were markedly effective and 5 cases were effective in the water cup group; 12 cases were clinically cured, 19 cases were markedly effective and 15 cases were effective in the empty cup group. There were significant differences in the ratio of cases of different therapeutic effects and the difference of pain score before and after treatment between the medicine cup group and the water cup group (P < 0.05), between the water cup group and the empty cup group (P < 0.05), and between the medicine cup group and the empty cup group (P < 0.01). CONCLUSION: The therapeutic effect of the distinctive medicine cup is better than the water cup group, and the water cup group is better than the empty cup group.

[Clinical study on moxibustion for treatment of abnormal blood lipids].

OBJECTIVE: To observe clinical therapeutic effect of moxibustion on abnormal blood lipids. METHODS: The patients who did not take the medicine for regulating blood lipids and had still abnormal blood lipids after diet therapy for 3 months, were divided into 4 groups according to different types of abnormal blood lipids. Forty cases selected in each group were again divided randomly into a treatment group and a control group. The treatment group were treated with moxibustion at Shousanli (LI 10), Zusanli (ST 36) and Shenque (CV 3) on the basis of diet therapy, and the control group only with the diet therapy. Their therapeutic effects were observed and compared after treatment of 90 days. RESULTS: There were significant differences between the treatment group and the control group in various groups of different types of abnormal blood lipids (P < 0.05). CONCLUSION: Moxibustion at Shousanli (LI 10), Zusanli (ST 36) and Shenque (CV 3) has a better therapeutic effect on abnormal blood lipids.