This research considers the mathematical relationship between concentration of Chla and seven environmental factors, i.e. Lake water temperature (T), Secci-depth (SD), pH, DO, CODMn, Total Nitrogen (TN), Total Phospho...This research considers the mathematical relationship between concentration of Chla and seven environmental factors, i.e. Lake water temperature (T), Secci-depth (SD), pH, DO, CODMn, Total Nitrogen (TN), Total Phosphorus (TP). Stepwise linear regression of 1997 to 1999 monitoring data at each sampling point of Qiandaohu Lake yielded the multivariate regression models presented in this paper. The concentration of Chla as simulation for the year 2000 by the regression model was similar to the observed value. The suggested mathematical relationship could be used to predict changes in the lakewater environment at any point in time. The results showed that SD, TP and pH were the most significant factors affecting Chla concentration.展开更多
After the declaration of the first case of Legionnaire's disease in Cameroon in 2007, the Centre Pasteur of Cameroon implemented the detection method for Legionella. The introduction of this new method was put in pla...After the declaration of the first case of Legionnaire's disease in Cameroon in 2007, the Centre Pasteur of Cameroon implemented the detection method for Legionella. The introduction of this new method was put in places in order to investigate Legionella spp. colonization of water distribution systems (WDS) of large buildings including hospitals, hotels and Off Shore Exploitations Sites (OSES) in an attempt to identify risk factors for Legionella spp. Water systems of 6 hotels, 6 hospitals and 6 ships were investigated for the presence of Legionella spp.. A total of 130 samples were collected, 77 from hotels, 27 from hospitals and 26 from ships. 51 Legionella spp. were isolated from 41 (31.54%) water samples. Of a total of 51 positive isolates, 40/51 (78.4%) were L. pneumophila with 21 (52.5%) Legionellapneumophila serogroup (sg) 1, 16 (40%) L. pneumophila sg 5, 2 (5%) L. pneumophila sg 6, 1 (2.5%) L. pneumophila sg 7 and 11/51 Legionella spp. with 10 (90%) L. anisa, 1 (10%) Legionella dumoffii. 5 L. pneumophila sg 1 were associated with 5 L. pneumophila sg 5 and 4 L. pneumophila sg 1 were associated with 4 L. anisa. These results showed that WDS of hospitals, hotels and ships can be heavily colonized by Legionella spp. and may present a risk of Legionnaires' disease. Based on these preliminary results, we have just put in place a Legionella survey protocol in Cameroon.展开更多
基金Project supported by the National Natural Science Foundation of China (No. 69673044) the Environmental Protection Bureau of Hangzhou (No. 9901), China
文摘This research considers the mathematical relationship between concentration of Chla and seven environmental factors, i.e. Lake water temperature (T), Secci-depth (SD), pH, DO, CODMn, Total Nitrogen (TN), Total Phosphorus (TP). Stepwise linear regression of 1997 to 1999 monitoring data at each sampling point of Qiandaohu Lake yielded the multivariate regression models presented in this paper. The concentration of Chla as simulation for the year 2000 by the regression model was similar to the observed value. The suggested mathematical relationship could be used to predict changes in the lakewater environment at any point in time. The results showed that SD, TP and pH were the most significant factors affecting Chla concentration.
文摘After the declaration of the first case of Legionnaire's disease in Cameroon in 2007, the Centre Pasteur of Cameroon implemented the detection method for Legionella. The introduction of this new method was put in places in order to investigate Legionella spp. colonization of water distribution systems (WDS) of large buildings including hospitals, hotels and Off Shore Exploitations Sites (OSES) in an attempt to identify risk factors for Legionella spp. Water systems of 6 hotels, 6 hospitals and 6 ships were investigated for the presence of Legionella spp.. A total of 130 samples were collected, 77 from hotels, 27 from hospitals and 26 from ships. 51 Legionella spp. were isolated from 41 (31.54%) water samples. Of a total of 51 positive isolates, 40/51 (78.4%) were L. pneumophila with 21 (52.5%) Legionellapneumophila serogroup (sg) 1, 16 (40%) L. pneumophila sg 5, 2 (5%) L. pneumophila sg 6, 1 (2.5%) L. pneumophila sg 7 and 11/51 Legionella spp. with 10 (90%) L. anisa, 1 (10%) Legionella dumoffii. 5 L. pneumophila sg 1 were associated with 5 L. pneumophila sg 5 and 4 L. pneumophila sg 1 were associated with 4 L. anisa. These results showed that WDS of hospitals, hotels and ships can be heavily colonized by Legionella spp. and may present a risk of Legionnaires' disease. Based on these preliminary results, we have just put in place a Legionella survey protocol in Cameroon.