Research Progress on Biological Evidence Identification in Fire Scenes.

Biological evidence is relatively common evidence in criminal cases, and it has strong probative power because it carries DNA information for individual identification. At the scene of fire-related cases, the complex thermal environment, the escape of trapped people, the firefighting and rescue operations, and the deliberate destruction of criminal suspects will all affect the biological evidence in the fire scene. Scholars at home and abroad have explored and studied the effectiveness of biological evidence identification in fire scenes, and found that the blood stains, semen stains, bones, etc. are the main biological evidence which can be easily recovered with DNA in fire scenes. In order to analyze the research status and development trend of biological evidence in fire scenes, this paper systematically sorts out the relevant research, mainly including the soot removal technology, appearance method of typical biological evidence, and possibility of identifying other biological evidence. This paper also prospects the next step of research direction, in order to provide reference for the identification of biological evidence and improve the value of biological evidence in fire scenes.

Antitumor and immunomodulatory activity of polysaccharides from the root of Limonium sinense Kuntze.

Limonium sinense (Girard) Kuntze is a traditional Chinese folk medicine used for the treatment of fever, hemorrhage, hepatitis and other disorders. The study focused on the antitumor and immunomodulatory activities of L. sinense polysaccharides (LSP) which was obtained from the root of the plant. The antitumor effects of only LSP and LSP in combination with 5-fluorouracil (5-FU) were both evaluated with Heps-bearing tumor mice models. In addition, the macrophage phagocytosis assay, splenocyte proliferation and cytokines production tests were used to assess the immunomodulatory activities of LSP. The results revealed that the LSP (at the dose of 200 and 400 mg/kg) had an obvious inhibition on the growth of transplanted mouse tumor. It also exhibited a significant synergistic effect of antitumor activity when combined with 5-FU (p<0.05). Furthermore, the LSP (at the dose of 100 and 200 mg/kg) remarkably improved macrophage phagocytosis function in immune suppressed mice. In addition, LSP (at the dose of 50-200 µg/ml) showed significant synergistic effects on ConA-stimulated proliferation and IFN-γ and IL-2 production of splenocyte in vitro (p<0.05). These findings suggest that LSP had clear antitumor activity which might be related to its regulation of immune function in mice.

The pollution control of fluorine and arsenic in roasted corn in "coal-burning" fluorosis area Yunnan, China.

Pilot experiments were carried out to reduce the fluorine (F) and arsenic (As) pollution of roasted corn dried by open ovens in "coal-burning" fluorosis area Yunnan, China. The results indicated that the average emission amount of F and As in briquettes in experimental group were 29.20mg/kg and 0.76 mg/kg in Xiaolongdong, and 46.8 mg/kg and 0.54 mg/kg in Mangbu respectively. The results also indicated that the fixing rate of F and As in briquettes in experimental group was more than 4 times and 1.2 times of that in control group respectively. The average concentration of F and As in roasted corn in experimental group were 3.86 mg/kg and 13.23 µg/kg in Xiaolongdong, and 4.77 mg/kg and 122.96 µg/kg in Mangbu respectively, which reduced by more than 65% and 75% respectively compared with that in control group. Adding local natural calcium-based materials in briquettes can reduce the emission of F and As and their pollution on roasted corn largely, and thus will reduce the risk of fluorosis for residents greatly in "coal-burning" fluorosis area of southwestern China.

[Determination of total selenium in water by hydride generation atomic fluorescence spectrometry].

In order to establish a rapid and accurate hydride generation-atomic fluorescence spectrometry method for the determination of selenium content in water samples, the influence factors on Se nitrolysis in the water such as nitrolysis temperature and the amount of hydrochloric acid were studied. The authors determined a simple and practical test method that is to add 3 mL hydrochloric acid at 3 degrees C. We measured the precision and accuracy of the method by the standard liquid of 3, 6 and 10 micro x L(-1), and the test results were 2.96, 5.43 and 9.66 mg x L(-1). The recovery varied from 90.50% to 98.67%. Meanwhile we tested 29 water samples by different methods. The error of standard sample was 8.95%-25.46% by hydride generation-atomic fluoresence spectrometry in the GB/T 5750. 6-2006, and the error of standard sample was 1.33%-3.40% by new method. Compared with the national standards of GB/T 5750.6-2006, the method has the advantages of operating simplicity and and easy control, and it is also reliable and economical.