Mammography screenings are effective and generate a 17% reduction in breast cancer mortality in women 39-49 years of age. The quality of the trials varies, and providers should inform women in this age group about the positive and negative aspects of mammography screenings.

In this paper, an integrated distributed fiber optic sensing technology, which includes Raman optical time-domain reflectometry (ROTDR), Brillouin optical time-domain analysis (BOTDA), and fiber Bragg grating (FBG) sensing technologies, is adopted to monitor the temperature and the stress/strain variations of a reinforced concrete pound lock structure during the construction process. The Raman optical time-domain reflectometry was used to monitor the internal temperature variation throughout the concrete curing process when concrete hydration heat was released in the base plate of the lock head. The FBG temperature sensors were adopted to measure the surface temperature of the concrete, and the temperature data were used to compensate the results that are measured by BOTDA sensing technology to get the real concrete strain of the base plate. To better understand the stress/strain state of the base plate before and after filling water in the lock, the BOTDA sensing cable and FBG temperature sensors monitoring continued throughout the whole construction process. The observation provided a positive indication that the proposed integrated distributed fiber optic sensing technology may have great potential in performance monitoring of hydraulic structures.

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Vacuum preloading combined with prefabricated vertical drains (PVDs) system has been widely used to improve the soft clay with high water content. Clogging is usually formed around the PVDs during the vacuum preloading, impeding the propagation of the vacuum pressure and slowing down the consolidation process. In order to understand the forming mechanism of the clogging, particle image velocimetry (PIV) technique and particle tracking velocimetry (PTV) technique were adopted in the model test of vacuum preloading test. Through this study, three stages can be identified from the results of water volume discharge rate and maximum displacements versus time. In the first stage, the soil around the PVD is horizontal consolidated, which leads to the rapid formation of clogging. In the second stage, the formation of clogging slows down due to the loss of vacuum pressure, which further reduces the drainage. In the third stage, the clogging tends to be stable, and the drainage consolidation rate is significantly reduced. PTV results show that there is difference in the displacement of large and small particles during improvement. Two methods were proposed to estimate the thickness of clogging zone, reflecting a growing layer of clogging zone compressed around the PVD. This study provides new insights to investigate the formation mechanism of clogging during vacuum preloading test.

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