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Pinus massoniana forests bordering South China are often affected by wildfires. Fires cause major changes in soil properties in many forest types but little is known about the effects of fire on soil properties in these P. massoniana forests. Such knowledge is important for providing a comprehensive understanding of wildfire effects on soil patterns and for planning appropriate long-term forest management in these forests. Changes in soil physical properties, carbon, nutrients, and enzymes were investigated in a P. massoniana forest along a wildfire-induced time span consisting of an unburned soil, and soils 0, one, four, and seven years post-fire. Soil (0-10 cm) was collected from burned and unburned sites immediately and one, four, and seven years after a wildfire. The wildfire effects on soil physical and chemical properties and enzyme activities were significantly different among treatment variation, time variation, and treatment-by-time interaction. Significant short-term effects on soil physical, chemical, and biological properties were found, which resulted in a deterioration of soil physical properties by increasing soil bulk density and decreasing macropores and capillary moisture. Soil pH increased significantly in the soil one-year post-fire. Carbon, total nitrogen (N) and phosphorus (P), and available N and P increased significantly immediately and one year after the wildfire and decreased progressively to concentrations lower than in the unburned soil. Total potassium (K) and exchangeable K increased immediately after the wildfire and then continuously decreased along the burned time-span. Urease, acid phosphatase, and catalase activities significantly decreased compared to those in the unburned soil. In fire-prone P. massoniana forests, wildfires may significantly influence soil physical properties, carbon, nutrients, and enzyme activity. [ABSTRACT FROM AUTHOR]

Background: Although China has a breast cancer incidence that surpasses all other cancer registries, there have been few reports to evaluate the relationships of reproductive history, steroid receptor status, and tumour markers with HER2 status of breast cancer. Patients and Methods: This project included 274 primary invasive ductal breast cancer patients. Information concerning the reproductive factors and tumour characteristics of the patients had previously been collected. HER2 and steroid receptor status were detected in tumour tissues. Serum CEA, CA15-3, and CA125 levels were analyzed for all patients. Results: Younger age at menarche was observed in patients with HER2-positive than in those with HER2negative status (p = 0.03). Statistically significant differences were found between the HER2-positive group and HER2-negative group for estrogen receptor (ER) and progesterone receptor (PR) status (p < 0.01). Age of onset, other reproductive factors, tumour characteristics, and serum tumour marker level were not significantly different between those patients with HER2-positive and those with HER2-negative status. Conclusion: We confirm that age at menarche may plausibly be differentially correlated with the risk of HER2-positive invasive ductal breast cancer because it is presumed to impact exposure to endogenous sex hormones. HER2 is inversely related to ER and PR in invasive ductal breast cancer patients of Northern China. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]