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Two goals for security scanning of cargo and freight are the ability to determine the type of material that is being imaged, and to do so at low radiation dose. One commonly used technique to determine the effective Z of the cargo is dual-energy imaging, i.e. imaging with different x-ray energy spectra. Another technique uses the fact that the transmitted x-ray spectrum itself also depends on the effective Z. Spectroscopy is difficult because the energy of individual x rays needs to be measured in a very high count-rate environment. Typical accelerators for security applications offer large but short bursts of x-rays, suitable for current-mode integrated imaging. In order to perform x-ray spectroscopy, a new accelerator design is desired that has the following features: 1)increased duty factor in order to spread out the arrival of x-rays at the detector array over time; 2)x-ray intensitymodulation from one delivered pulse to the next by adjusting the accelerator electron beam instantaneous current so as to deliveradequate signal without saturating the spectroscopic detector; and 3)the capability to direct the (forward peaked) x-ray intensity towards high-attenuation areas in the cargo (“fan-beam-steering”). Current sources are capable of 0.1% duty factor, although usually they are operated at significantly lower duty factors (∼0.04%), but duty factors in the range 0.4-1.0% are desired. The higher duty factor can be accomplished, e.g., by moving from 300 pulses per second (pps) to 1000 pps and/or increasing the pulse duration from a typical 4 μs to 10 μs. This paper describes initial R&D to examine cost effective modifications that could be performed on a typical accelerator for these purposes, as well as R&D for fan-beam steering.

Background: General pharmacology is the backbone of therapeutic pharmacology. In general pharmacology, pharmacokinetics is a very difficult topic for undergraduate medical students. Knowledge of the kinetics and of the effects of drugs is necessary for the correct use of drugs in therapy. As in the body most of the drugs follow first order elimination kinetics, so it is necessary for all students to know about basic concept of first order kinetics. This can be easily understood by using working models. Our present study is a step in that direction. The objective of this study was planned to develop first order elimination kinetics working models to teach pharmacokinetics principle to the under graduate medical students. Methods: The current study was planned and executed by the department of pharmacology in SHKM government medical college, Mewat, Haryana, India in the first quarter of 2016. This model was developed from household waste materials like thermocol sheets, coke bottles, waste water pipe, colour etc. Results: As we know learning is better with live experimentation as compare to theoretical learning, so difficult topics such as elimination kinetics will be taught by help of working models. Conclusions: First order elimination kinetics is easily understood with the help of above working model. More and more working models could be developed for teaching difficult topics.

The central calorimeter in Fermilab experiment E760 ++ has been designed to measure the topology and energies of electrons and photons in the decay of charmonium formed in p p annihilation. The calorimeter is composed of 1280 lead-glass Cherenkov counters read out with photomultiplier tubes. This paper discusses design criteria for the calorimeter and describes how these criteria were met. Data from tests in low energy (10–84 MeV) and medium energy (1–4 GeV) beams are presented showing a spatial resolution of 9 mm, an energy resolution of (3.0 ± 0.3)% √E[ GeV ] + (1.5 ± 0.5)% , and an effective energy threshold below 10 MeV.