Analytic Method on Characteristic Parameters of Bacteria in Water by Multiwavelength Transmission Spectroscopy

An analytic method together with the Mie scattering theory and Beer-Lambert law is proposed for the characteristic parameter determination of bacterial cells (Escherichia coli 10389) from multiwavelength transmission spectroscopy measurements. We calculate the structural parameters of E. coli cells, and compared with the microscopy, the relative error of cell volume is 7.90%, the cell number is compared with those obtained by plate counting, the relative error is l.02%, and the nucleic content and protein content of single E. coli cells are consistent with the data reported elsewhere. The proposed method can obtain characteristic parameters of bacteria as an excellent candidate for the rapid detection and identification of bacteria in the water

Application of the affine stochastic model on Singapore mortality data.

In recent years, stochastic modeling has become a buzz word in the finance industry and the phenomenal advantages of stochastic models have attracted immense attention from researchers. Here, we fit Singapore's mortality rates to an affine stochastic state-space model. The model is fitted through maximum likelihood estimation process, which in our project relies on the assumption of white and normal innovations in the state-space model. Kalman Filter technique is adopted to facilitate the derivation of the maximum-likelihood estimators (MLE) and EM-algorithm with direct search technique is applied in finding the numeric estimates for the MLE. The affine stochastic state-space model allows us to capture two important features of mortality rates: time dependency and uncertainty of the future development. This model gives us more realistic premiums and reserves, and it quantifies the risk of the underlying mortality rates. We also examine the effects on profitability of insurance products that are linked to the development of the mortality rates

A Review on Heavy Metal Pollution of Agricultural Land Soil in the Yangtze River Delta and Relevant Pollution Control Strategy

The Yangtze River Delta is an important industrial and agricultural production base in China. It is significant to pay attention to the heavy metal pollution of agricultural land in the Yangtze River Delta for promoting the healthy development of social economy and for ensuring the safety of ecological environment in China. In this paper, the accumulation and pollution status of typical heavy metals in the agricultural land soil in different regions of the Yangtze River Delta were comprehensively analyzed and the main reasons for the pollution were systematically discussed, according to the heavy metal content data reported in relevant literatures published over the past 20 years. The analysis revealed that due to industrial “three wastes” emissions, transportation, and the extensive use of fertilizers, pesticides, and agricultural films, Cd accumulation and pollution in the agricultural land soil of the entire Yangtze River Delta is the most serious, followed by Cu, Hg and Pb pollution; specifically, Taizhou (in Zhejiang Province) has a compound pollution problem of Cd, Hg, and Cu while Tongling (in Anhui Province) has a compound pollution problem of Cd, Pb, and Cu. To meet the urgent need for the prevention and control of heavy metal pollution in the Yangtze River Delta and considering the main causes of pollution, some suggestions were proposed, including source control, rapid and dynamic monitoring, hierarchical management of agricultural land, research and development of new technologies for soil remediation, and legislation on prevention and control of agricultural land soil pollution. It is hoped that this research can provide a reference for improving the soil ecological environment in the Yangtze River Delta and promoting the sustainable development of a high-quality and efficient agriculture