Nearfield Imaging for Noninvasive Monitoring of Hyperthermia Treatment

Hyperthermia treatment has the potential to enhance cancer therapy and reduce the side effects associated with conventional therapeutic plans. Commercial systems depend typically on narrowband operation and exploit single element applicators to drive energy into treated tissue. In addition, monitoring of thermal distribution depends on invasive intraluminal or interstitial probes. This research aims at developing a proficient platform that addresses some challenges of hyperthermia therapy. A system is suggested that depends on multichannel wideband operation, and implements applicator array. The configuration of this system allows the control of energy localization at various depth of tumors. In addition, the information associated with scattered wideband signals allow performing nearfield imaging, to reconstruct tissue characteristics maps. To investigate system performance, a model is developed of the forward problem, incorporating dispersive wideband models of tissue properties. A tool is developed to generate a dictionary that relates scattered signals to material features. Solution of the inverse problem is conducted based on compressed sensing techniques. Orthogonal matching pursuit OMP models are developed to enhance the resolution of image reconstruction. With the dependence of tissue electrical properties on temperature, thermal maps are generated. Practical aspects of the nonlinearity associated with wideband power amplifiers are incorporated in the model. Analysis of the reconstructed images reveals the validity of the proposed techniques. In particular, encouraging results are obtained of thermal mapping, denoting the potential of using nearfield imaging as a noninvasive thermometry tool, in monitoring hyperthermia treatment

Indexing multi-dimensional uncertain data with arbitrary probability density functions

Research Session 26: Spatial and Temporal DatabasesIn an "uncertain database", an object o is associated with a multi-dimensional probability density function (pdf), which describes the likelihood that o appears at each position in the data space. A fundamental operation is the "probabilistic range search" which, given a value p q and a rectangular area r q, retrieves the objects that appear in r q with probabilities at least p q. In this paper, we propose the U-tree, an access method designed to optimize both the I/O and CPU time of range retrieval on multi-dimensional imprecise data. The new structure is fully dynamic (i.e., objects can be incrementally inserted/deleted in any order), and does not place any constraints on the data pdfs. We verify the query and update efficiency of U-trees with extensive experiments.postprintThe 31st International Conference on Very Large Data Bases (VLDB 2005), Trondheim, Norway, 30 August-2 September 2005. In Proceedings of 31st VLDB, 2005, v. 3, p. 922-93

Reproductive Toxicity Induced by Low Dose Bisphenol A(BPA) in Male Rats

Bisphenol A(BPA) an endocrine disruptor used in the manufacturing process of plastic. BPA low doses on long exposure periods had many hazardous effects. The aim of the present study was to assess the effect of lowest dose of BPA on the male induced orally on the at reproductive performance and changes in the testes that takes place histologically. P53 gene expression by Realtime PCR was also evaluated. Seventy- two albino male rats were divided into two groups, group I (control male rats receiving corn oil only). Group II (64 male rats) which was treated with oral doses of 50 µg/ kg/ day daily for 8 weeks. Every week 8 male rats were dissected and subjected to the investigated parameters. BPA treated groups presented decrease in sperms count, motility, progression and viability as well as a significant increase in sperms head or/and tail abnormalities were recognized. Histology of the testes showed abnormal and irregular organization of seminiferous tubules and decreased sperms in the testes lumen. Moreover, up-regulation in p53 expression was recorded after BPA exposure. In conclusion, these results showed that exposure to BPA at low dose 50µg/kg can cause many reproductive disorders which may impair fertility