[Pollution Source Apportionment of Heavy Metals in Cultivated Soil Around a Red Mud Yard Based on APCS-MLR and PMF Models].

In order to explore the characteristics and sources of heavy metal pollution in cultivated soil around a red mud yard in Chongqing， the content and spatial distribution characteristics of eight heavy metal elements （Cd， Cr， Hg， Ni， Pb， As， Cu， and Zn） in the soil were analyzed， and the single factor pollution index method and Nemerow comprehensive pollution index method were used to evaluate the characteristics of heavy metal pollution in soil. On the basis of correlation analysis， the APCS-MLR and PMF models were used to quantitatively analyze the sources of heavy metals. The results showed that the average contents of the other seven heavy metal elements were higher than the background values of Chongqing soil， except for that of Cr. The heavy metals Cd， Hg， and As were moderately polluted， and Pb， Cu， Ni， and Zn were mildly polluted. The spatial distribution pattern of Cr， Ni， Pb， Cu， and Zn in the soil was similar， and there was a very significant positive correlation between them （P < 0.01）. The spatial distribution characteristics of Cd， Hg， and As were significantly different， and there was no significant correlation between them （P > 0.05）. The source apportionment showed that the sources of heavy metals in the soil in the study area were relatively complex， and the APCS-MLR and PMF models could identify the same four pollution sources， namely red mud yard percolation emission and natural sources， thermal power generation emission sources， agricultural activities and natural sources， and non-ferrous metal smelting emission sources. There was little difference in the results of source apportionment between the two models. The contribution rates of the four pollution sources in the APCS-MLR model were 51.8%， 18.0%， 15.9%， and 14.3%， respectively， whereas those in the PMF model were 45.9%， 12.8%， 21.5%， and 19.8%， respectively.

[Spatial and Temporal Distribution and Risk Assessment of Heavy Metals in Surface Water of Changshou Lake Reservoir, Chongqing].

To understand the water pollution status and environmental risks of Changshou Lake, the concentrations of heavy metals (Cr, Cu, Zn, As, Cd, and Pb) in the water were collected and analyzed during different seasons. The study investigated temporal and spatial variations, distribution characteristics, pollution levels, and health risks associated with heavy metals in Changshou Lake. The results showed that all six heavy metals were below than the Class Ⅰ standard of the Surface Water Environmental Quality Standard (GB 3838-2002), but recent years have witnessed an increasing trend, with Cu, As, and Pb showing a significant increase (P<0.05). The temporal and spatial distributions of these heavy metals were different. Temporally, Cr and Cd concentrations in surface water were higher in summer, As and Zn were higher in spring, and Pb and Cu were higher in autumn and winter. Spatially, the concentrations of Cr, As, Cu, Zn, and Pb showed higher concentrations in the southern outlet of the reservoir, the northwestern Longxi River inlet, and the central part of the reservoir, whereas Cd was higher in the northern stagnant area. The overall levels of heavy metals in the water body of Changshou Lake were low, with Cr and Cu slightly polluted, while other heavy metals were identified as having an insignificant pollution level. Drinking water was the primary exposure pathway to carcinogenic and non-carcinogenic heavy metals in surface water bodies. The health risk values of Cr and As in water bodies were high, ranging from 6.2×10-10 to 3.0×10-4 and 5.1×10-8 to 3.9×10-5, respectively. The corresponding contribution rates for children and adults to the total health risk were high, with Cr accounting for 87.18% and 87.20%, respectively, while As accounted for 12.73% and 12.71%, respectively. Therefore, it is crucial to prioritize environmental risks associated with Cr and Cu, as well as the health risks associated with Cr and As in Changshou Lake These findings provide a scientific foundation for water pollution control and environmental quality improvement in Changshou Lake, and rational development and utilization of water resources.

Effect of lower-molecular weight heparin in the prevention of pancreatic encephalopathy in the patient with severe acute pancreatitis.

OBJECTIVE: To study the effect of lower-molecular weight heparin in the prevention of pancreatic encephalopathy (PE) in the patient with severe acute pancreatitis (SAP). METHODS: Two hundred sixty-five SAP patients were randomly divided into 2 groups: (1) conventional treatment group (C group, n = 130) and (2) conventional treatment plus lower-molecular weight heparin treatment group (LT group, n = 135). The clinical parameters, laboratory parameters and computed tomographic (CT) score of pancreatic necrosis (CTSPN), incidence of PE, and mortality in the 2 groups were compared. RESULTS: On admission, all the clinical parameters, laboratory parameters, and CTSPN in the 2 groups were not significantly different (P > 0.05). However, 1 to 2 weeks after treatment, the symptoms and signs improvement rate, the levels of blood and urine amylase, the CT score, and the Acute Physiology and Chronic Health Evaluation II score in the LT group were obviously lower than those in the C group (P < 0.05-0.01), and PE occurrence rate, mortality, and mean hospital stay in LT group were obviously lower than those in the C group (P < 0.05-0.01). CONCLUSIONS: Lower-molecular weight heparin can enhance the effect of conventional treatment of SAP and can markedly decrease the PE incidence and improve the survival rate of SAP. Lower-molecular weight heparin is a simple, safe, less expensive, and effective method for treatment of SAP. It can be used in every hospital.

Low molecular weight heparin in the treatment of severe acute pancreatitis: a multiple centre prospective clinical study.

OBJECTIVE: To study the effect of low molecular weight heparin (LMWH) in the treatment of severe acute pancreatitis (SAP). METHODS: A total of 265 SAP patients were randomly divided into two groups: firstly, the conventional treatment group (C group, n = 130; and secondly the conventional treatment plus the LMWH treatment group (LT group, n = 135). The clinical parameters, laboratory parameters and computed tomography (CT) score of pancreatic necrosis (CTSPN) in the two groups were compared. RESULTS: On admission, all the clinical parameters, laboratory parameters and CTSPN in the two groups were not significantly different (p > 0.05). However, after treatment, in LT group, the clinical presentation improvement rate and laboratory parameters improvement were significantly higher than those in C group (p < 0.05-0.01), and the acute physiology and chronic health evaluation (APACHE) II score, complication rate, mortality and mean hospital stay in LT group were obviously lower than those in C group (p < 0.05-0.01). The CT score in LT group was much lower than that in C group (p < 0.05). Two weeks after treatment FBI decreased obviously in C group, but not in LT group, and no haemorrhagic complications occurred. CONCLUSIONS: LMWH can enhance the effect of conventional treatment for SAP, and can markedly decrease the mortality of SAP. LMWH is a simple, safe, economic and effective method for treatment of SAP. It is can be used in every hospital.

Analysis of segregation distortion of molecular markers in F2 population of rice.

A genetic linkage map comprising 148 SSR markers loci was constructed using an F2 population consisting of 90 lines derived from a sub-specific cross between a japonica variety Nipponbare and an indica variety Guangluai-4. The F2 population showed high significantly distorted segregations. Among these SSR markers, 49 markers(33.11%) showed the genetics distortion(P<0.05). Of them, 36 markers deviated toward male parent indica GuangLuAi-4 and 13 markers toward heterozygote, but none toward the female parent Nipponbare. It was found that the segregation distortion might be caused by gametophyte and zygote. Since most gametophyte loci and sterility loci were mapped in segregation distortion regions, it indicated that the segregation distortion may be caused by these gametophyte loci and sterility loci. Finally, this research also analyzed the skewed segregation of some markers, which had not been mapped on chromosome.

Construction of a microsatellite linkage map with two sequenced rice varieties.

Based on the successful development of new microsatellite markers from the data of two whole-sequenced rice varieties, japonica variety Nipponbare and indica variety 9311, an F2 population of 90 lines, which was derived from a single cross between Nipponbare and 9311, was applied to construct a genetic linkage framework map. The map covered 2 455.7 cM of total genomic length, and consisted of 152 simple sequence repeats (SSRs) loci including 46 pairs of new SSR primers developed by our research institute. The average genetic distance between two markers was 16.16 cM. In addition, markers RM345 and RM494, which have not been mapped on the Temnykh's map et al. (2001) were anchored on the sixth chromosome of this map. We compared this research with maps of Temnykh et al.(2001) and LAN et al. (2003) regarding the aspects of type and size of population, type and quantity of markers, and the marker arrangement order on chromosome, etc. Results indicated that the similarity of marker linear alignment was 93.81% between this map and T-map. Finally, the important significance of using sequenced rice varieties to construct linkage map was also discussed.