Breast cancer is the second most common fatal cancer in women. Developing a breast cancer is a multi-factorial and hormonal-dependent process, which may be triggered by many risk factors. An endocrine disrupting substance known as bisphenol A (BPA), that is used greatly in the manufacture of plastic products, was suggested as a possible risk factor for developing breast cancer. BPA has a strong binding affinity to non-classical membrane estrogen receptors like estrogen-related and G protein-coupled (GPER) receptors. Based on animal and in vitro studies, results showed a link between BPA exposure and increased incidence of breast cancer. BPA has the ability to alter multiple molecular pathways in cells namely, G protein-coupled receptor (GPER) pathway, estrogen-related receptor gamma (ERRγ) pathway, HOXB9 (homeobox-containing gene) pathway, bone morphogenetic protein 2 (BMP2) and (BMP4), immunoregulatory cytokine disturbance in the mammary gland, EGFR-STAT3 pathway, FOXA1 in ER-breast cancer cells, enhancer of zeste homolog 2 (EZH2), and epigenetic changes. Thus, the aforementioned alterations cause undesired gene stimulation or repression that increase risk of developing breast cancer. So, restricting exposure to BPA should be considered to aid in lowering the risk of developing breast cancer.

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Radial thrust in a single volute centrifugal pump, which is a result of pressure variation in the volute casing, is investigated in order to avoid failures caused by this thrust force. Two ideas are introduced to avoid or to minimize this thrust force, the first is a double volute, and the second is a triple volute. A complete centrifugal pump design was manufactured. The volute was designed such that partition vanes could be added to change the number of volutes. Experiments were performed on single volute centrifugal pump, double volute centrifugal pump and triple volute centrifugal pump at 500, 800, and 900 rpm for each case. The thrust values of the double volute pump are always lower than that of the single volute pump specially when operating far from the best efficiency point where, the radial thrust is reduced by more than 55% at shut off and more than 40% at high discharges, while the thrust values of the triple volute are always lower than that of the single volute and double volute pumps specially when operating far from the best efficiency point where, the radial thrust is reduced by more than 70% at shut off and more than 50% at high discharges comparing to single volute and the radial thrust is reduced by more than 40% at shut off and more than 20% at high discharges comparing to double volute. However, it is to be mentioned that the best pump efficiency is always obtained for the single volute pump, compared with the other alternatives.

Radial thrust in a single volute centrifugal pump, which is a result of pressure variation in the volute casing, is investigated in order to avoid failures caused by this thrust force. Two ideas are introduced to avoid or to minimize this thrust force, the first is a double volute, and the second is a triple volute. A complete centrifugal pump design was manufactured. The volute was designed such that partition vanes could be added to change the number of volutes. Experiments were performed on single, double, triple volutes centrifugal pump at 500, 800, and 900 rpm for each case. The performances of the three pumps as seen on a non-dimensional plot, are nearly the same in the three casing types (Single, double and triple volutes). However, the values of the efficiency reveal an improvement associated with the presence of the volute(s) On the other hand, the use of multiple volutes reduced the radial thrust force. These reductions were pronounced as the departure from the BEP was increased. At shut off for instance, the radial thrusts for the double volutes and triple volutes were reduced by 55% and 70%, respectively, below the thrust of a single volute pump.