A practice of ultra-fine tailings disposal as filling material in a gold mine.

A practice of cemented backfill technology with ultra-fine tailings in a gold mine was comprehensively presented, and a series of tests were conducted in accordance with the peculiar properties of ultra-fine tailings and the mining technology conditions. The test results show that, the tailings from Shuiyindong Gold Mine have a great grinding fineness, with the average particle diameter 22.03 µm, in which the ultra-fine particles with the diameter below 20 µm occupying 66.13%. The analysis results of chemical components of tailings indicate that the content of SiO2 is relatively low, i.e., 33.08%, but the total content of CaO, MgO and Al2O3 is relatively high i.e., 36.5%. After the settlement of 4-6 h, the tailing slurry with the initial concentration of 40% has the maximum settling concentration of 54.692%, and the corresponding maximum settling unit weight is 1.497 g/cm3. During the field application, the ultra-fine tailings and PC32.5 cement were mixed with the cement-tailings ratios of 1:3-1:8, and the slurry concentration of 50 wt% was prepared. Using the slurry pump, the prepared cemented backfill slurries flowed into the goaf, and then the strength of the cemented backfill body met the mining technique requirements in Shuiyindong Gold Mine, where the ore body has a smooth occurrence, with the average thickness of approximately 2 m and the inclination angle ranging from 5 to 10°.

Relationship between UV-irradiated HaCaT cell cytokines and Th1/Th2 imbalance.

We have previously found that an imbalance of Tc1/Tc2 T cell subtypes in vivo impacts the development of photodermatitis. The aim of this study was to investigate the relationship between cytokines derived from keratinocytes exposure to UV and the imbalance of Th subgroups. We used different doses of UVA and UVB to irradiate HaCaT cells. Twelve hours after irradiation, the expression of IL-10R, IL-4R, IL-12R, and IFN-γR proteins was observed using the S-P method, and the percentage of positive cells calculated. Protein levels of the respective ligands in the supernatant was measured by ELISA. Our results showed low levels of expression of the interrogated proteins in unirradiated HaCaT cells, and little or no expression could be detected in the supernatant. Little or no expression was also observed for IL-12R and IFN-γR 12 h after UVA or UVB irradiation. However, the expression of IL-10R and IL-10 was upregulated 12 h following UVB irradiation, as well as following lower dose UVA irradiation. In contrast, higher dose UVA decreased the expression of IL-10R and IL-10. The expression of IL-4R was increased following high doses of UVA and UVB irradiation, whereas no expression was observed after lower dose UV exposure. There was no change in IL-4 secretion into the supernatant. Our results demonstrate that the effects of UV exposure on keratinocyte-derived cytokines are different according to the doses of irradiation and the types of cytokines, and suggest that keratinocyte-derived cytokines after UV exposure might cause an imbalance of Th1/Th2.

Systemic lupus erythematosus patients in the low-latitude plateau of China: altitudinal influences.

The current study was to investigate the features of hospitalized patients with systemic lupus erythematosus (SLE) at different altitudes. The correlation between SLE activity and altitudinal variations was also explored. Medical records of 1029 patients were retrospectively reviewed. Activity of SLE in each organ system was recorded using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). There was no significant correlation between SLE activity and altitudes (r = 0.003, p = 0.159). Age at onset for SLE patients at high altitudes was significantly younger than that at low and moderate altitudes (p = 0.022 and p = 0.004, respectively). Age at SLE admission at low altitudes was significant older than those at moderate and high altitudes (p = 0.011 and p < 0.001, respectively). Patients at high altitudes had shorter duration from disease onset to admission than those at moderate altitudes (p = 0.009). Incidence of Sm antibodies-positive for resident patients at high altitudes was 36.4%, which were higher than that at moderate altitudes (p = 0.003). We found increasing trends of CNS activity in active patients; immunological and renal activities in inactive patients were correlated with elevated altitudes (p = 0.024, p = 0.004, p = 0.005), while arthritis scores in active patients showed the tendency of decreasing with the rise of elevation (p = 0.002). Hemoglobin level, red blood cell and platelet counts at high altitudes were significantly lower than those at low altitudes (p < 0.05, respectively). There was no significant difference in hemoglobin level between moderate- and low-altitude groups (p > 0.05). No significant difference in platelet counts between moderate- and high-altitude groups was observed (p > 0.05). Our findings suggest that some clinical features, laboratory tests and activity of main organs in SLE are influenced by altitudes. Furthermore, organ activities of active and inactive SLE patients have different patterns of altitudinal variations. These distinctive variations likely reveal that peculiar environmental factors at high altitudes can affect the development of SLE.

Agminated spitz nevi: case report and review of the literature.

Spitz nevi are benign melanocytic lesions with many histologic similarities to malignant melanoma. A case of agminated Spitz nevi on a 2-year-old boy's left cheek is reported and 41 other cases of agminated Spitz nevi are reviewed. In this case, two biopsies were performed on two different-appearing lesions and the results of both biopsies showed Spitz nevi.

Isolated skull cryptococcosis in an immunocompetent patient.

A 62-year-old immunocompetent rural woman who represents an isolated cryptococcal skull infection without systematic involvement is described. Diagnosis was based on positive India ink staining, positive histopathologic examination, and positive culture. Species identification was performed by growth on Sabouraud dextrose agar and CHROMagar medium and by sequencing of the intergenic and internal transcribed spacer regions of the rRNA genes. This case describes a rare presentation of Cryptococcus neoformans infection in a human immunodeficiency virus-negative patient. The lesions were significantly improved with treatment of daily oral itraconazole 400 mg. A maintenance therapy with a low-dose itraconazole was prescribed to warrant a clinical and mycological eradication. A two-year follow-up did not show any recurrence of infection.

Pressure dependence of ozone interference in the laser fluorescence measuremens of OH in the atmosphere.

Experimental results are presented on the pressure dependence of ozone interference. Good agreement was observed between these results and relevant theoretical considerations. It is pointed out that chemical modulation can lead to sizable amounts of spurious signal in the presence of ozone dissociation.