The accident at the Fukushima Daiichi Nuclear Power Station (FDNPS) following the Great East Japan Earthquake and the subsequent tsunami in March 2011 changed people's perceptions regarding nuclear power gene...
详细信息
The accident at the Fukushima Daiichi Nuclear Power Station (FDNPS) following the Great East Japan Earthquake and the subsequent tsunami in March 2011 changed people's perceptions regarding nuclear power generation in Japan and worldwide. The failure to prevent the accident and the response to it had an enormous impact specifically on the communities close to the site but also across Japan and globally. In this review, I discuss radiation detection technologies, their use and limits in the immediate assessment and response, and improvements since then. In particular, I examine recent developments in radiation detection and imaging systems that, in combination with the enormous advances in computer vision, provide new means to detect, map, and visualize radiation using manned and unmanned deployment platforms. In addition to smarter and more adaptable technologies to prevent and minimize the impact of such events, an important outcome of this accident is the need for informed and resilient citizens who are empowered by knowledge and technologies to make rational decisions. The accident at FDNPS leaves a legacy concerning the importance of historical information, technologies, and resilience as well as challenges regarding powerful technologies that can provide substantial benefits to human society but that are also associated with risks of which we must be aware.
Mathematical models of the human left ventricle are presented to determine the physiological response-oriented mechanical parameters of the LV, which have diagnostic significance. These parameters are (i) the rheologi...
详细信息
Mathematical models of the human left ventricle are presented to determine the physiological response-oriented mechanical parameters of the LV, which have diagnostic significance. These parameters are (i) the rheological parameters of the left ventricular muscle, namely the instantaneous values of stiffness of series elasticity, parallel elasticity, and the stress-strain rate relationship for the contractile unit that characterizes the deviatric stress-strain response of a left ventricular muscle element, (ii) the effective modulus of the LV, and (iii) the state of stress in the LV. The rheological parameters are obtained from a continuum model of the LV whose stress state equilibrates the chamber pressure and whose strain state equals the instantaneous strains in the actual LV, obtained from instantaneous changes in the geometry of the LV (as noted from cineangiocardiography); the constitutive equations for the model incorporate the known existing rheological models for the isolated cardiac muscle. The effective moduli of the LV are obtained by correlating the fundamental frequency of vibration of a spherical model of the LV with the corresponding frequencies of the second component of the first heart sound and the third heart sound; thus the values of representative moduli (and hence indices of the left ventricular stiffnesses) at systole and diastole are obtained. The stress state in the LV is obtained by utilizing single plane cineangiocardiographic information of the irregular geometry of the LV in anteroposterior projection. Plane stress finite element analysis of this planor irregular geometry of the LV is done and the resulting stresses are reduced by a factor, heuristically determined to make allowance for the actual 3-dimensional geometry of the LV; the stresses obtained thus bring out effects of irregular boundary of varying (and at times high) curvature.
Detection of weak magnetic fields arising from neuronal electrical activities using magnetic-resonance imaging (MRI) is a potentially effective method for functional imaging of the brain. The purpose of this study is ...
详细信息
The present study demonstrated the measurement of Nae/Na i in sciatic nerves by 23Na-MRS using 23Na frequency shift agent Na4 HTmDOTP. Sciatic nerves from bull frogs were submerged into the 5 mM TmDOTP solution for 12...
详细信息
Biological sensors intended for clinical use can have requirements which are quite different from those normally associated with biological research. In fact the requirements can be surprisingly severe when involved w...
详细信息
Biological sensors intended for clinical use can have requirements which are quite different from those normally associated with biological research. In fact the requirements can be surprisingly severe when involved with the diagnosis and/or treatment of the seriously ill. Such requirements, if not realized and fully understood at the beginning of development, can greatly increase the time and cost of development and can endanger the acceptance of a new instrument by the medical fraternity. I shall discuss some of these special requirements and consequent developing problems. I have chosen to limit my considerations to cardiovascular sensors partly because of time limitations and partly because they do afford succinct examples of problems involved with seriously ill patients.
暂无评论