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The dual objectives of this study are to: (1) examine the relationship between COD and BOD in seawater environment with a rapid but reliable method for the measurement of BOD in seawater, and (2) establish the relationship model between BOD5 and COD in the firth of Dongbao River to predict the values of BOD5. The first objective is met by the successful development of a technique utilizing bacteria-immobilized membrane flow cell for biodegradation process, coupled with fibre optic fluorescence detection for oxygen depletion quantitation. The technique has been applied to coastal seawater samples collected in the coastal area of Shenzhen, China. The BOD5 and COD values for the samples are acquired and the results show that there is no apparent linear relationship existing between BOD5 and COD in relatively clean seawater samples away from the shore. However, in estuary water samples containing relatively high concentration of sewage contamination, a linear correlation does exist between BOD5 and COD. The linear relationship between the two parameters allows for the calculation of BOD5 values based on COD data which can be measured more readily and precisely. [ABSTRACT FROM AUTHOR]

Mangrove wetlands have been rapidly diminishing because of human pressures worldwide. The Guangdong Province in South China, which has the largest area of mangrove wetlands in the nation, is under severe threat as a result of rapid urbanization and economic development. In this paper, comparisons were made between optical Landsat TM images and Radarsat fine-mode images for estimating wetland biomass. Regression and analytical models were used to establish the relationships between remote sensing data and wetland biomass. The optimal parameter values for the analytical model were determined using genetic algorithms. Experiments indicate that the models using Radarsat fine-mode images have significant accuracy improvement in terms of Root Mean-Square Error (RMSE) whereas the use of the single Normalized Difference Vegetation Index (NDVI) may produce serious errors in biomass estimation. The Radarsat images can obtain more accurate trunk information about mangrove forests because of higher resolution and side-looking geometry. The use of genetic algorithms can help to decompose backscatter into vegetation and soil backscattering, which is very useful for ecological modelling. [ABSTRACT FROM AUTHOR]

HIV/STD surveillance system data are important for developing prevention and control programmes for men who have sex with men (MSM), now a core group in Chinese HIV/STD surveillance activities. MSM were recruited from different settings in Shenzhen and were tested for HIV and syphilis. A substantial prevalence of HIV and syphilis infections was found in this population. However, risk behaviours and sociodemographic characteristics varied greatly among MSM recruited from the different settings (gay sauna, gay bar and MSM clinic), suggesting that carefully considering and selecting appropriate settings to represent the MSM population is critical for developing HIV and STD surveillance and prevention programmes. [ABSTRACT FROM AUTHOR]

The prevalence of cancer related germline mutations in unselected Chinese breast cancer (BC) patients is unknown. Our study aims to examine the germline mutations prevalence and to investigate the relationship among tumor characteristics, somatic mutations and germline mutations. Matched white blood cells and tumor tissue samples of 524 unselected Chinese BC patients (stage Tis to IV) were profiled using a panel consisting of 520 cancer-related genes. Germline mutations of 62 cancer susceptibility genes included all breast/ovarian cancer-related genes in the US genetic guidelines were assessed. A total of 76 pathogenic or likely pathogenic (P/LP) germline variants spanning 15 genes were detected from 58 patients (11%), with 29 and 38 mutations detected in BRCA1/2 and other cancer susceptibility genes, respectively. Overall, mutations detected included 11 BRCA1, 18 BRCA2, 4 MUTYH, 4 PALB2, 3 ATM, 3 BRIP1, 3 CDH1, 3 RAD51C, 2 CHEK2, 2 FANCA, 2 PMS2, 2 TP53, 1 FANCI, 1 FANCL and 1 PTEN. We detected 1968 germline mutations classified as variants of uncertain significance spanning all 62 cancer susceptibility genes from 490 patients (93%). We revealed young age, premenopausal status, and family history of breast/ovarian cancer were associated with P/LP germline mutations. Interestingly, somatic TP53 mutations were detected in all patients with P/LP germline BRCA1 mutations (100%, 11/11) and a majority (67%, 2/3) of patients with likely pathogenic CDH1 mutations. No somatic TP53 mutation was detected in patients with germline ATM and TP53 mutations. Somatic PIK3CA mutations were more frequently seen in patients with germline CDH1 (3/3). A patient with pathogenic germline PALB2 mutation (p.Q921fs) also has somatic PALB2 mutation (p.D525fs). Our study derived the prevalence of P/LP germline mutation in 524 Chinese BC patients and 11% were found to have a germline mutation. We explored the characteristics of tumor somatic mutations in germline mutations carriers, which provided a better understanding of patients with germline mutations. Ning Liao. National Natural Science Foundation of China (Grant No. 81602645), Guangdong Provincial Natural Science Foundation (Grant No. 2016A030313768). All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]