There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

An emerging field of plasma medicine is discussed, where non-equilibrium plasmas are shown to be able to initiate, promote, control, and catalyze various complex behaviors and responses in biological systems. More importantly, it will be shown that plasma can be tuned to achieve the desired medical effect, especially in medical sterilization and treatment of different kind of skin diseases. Wound healing and tissue regeneration can be achieved following various types of plasma treatment in a multitude of wound pathologies. Non-equilibrium plasmas will be shown to be non-destructive to tissue, safe, and effective in inactivation of various parasites and foreign organisms.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppap.200700154

Applied Plasma Medicine

At 6.3 billion solar masses, the central black hole in the supergiant elliptical galaxy M87 has been regarded as the most massive known black hole in the Universe for more than three decades. This paper reports two galaxies containing black holes that exceed that figure. NGC 3842 has a central black hole of 9.7 billion solar masses, and NGC 4889 has one of comparable or greater mass. Indications of such massive black holes have existed in the early Universe from luminous quasars but have eluded our detection; these results are the first to connect these early massive black holes to host galaxies in the nearby Universe.

/pdf/two-ten-billion-solar-mass-black-holes-at-the-centres-of-3a2svxmz8m.pdf

Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies

소형 안테나 ( Small Antennas )

Disclosed are therapeutic methods for the treatment of diseased, disease-causing, or undesirable tissue or material that involve the administration of a thermotherpeutic magnetic composition, which contains single-domain magnetic particles attached to a target-specific ligand, to a patient and the application of an alternating magnetic field to inductively heat the thermotherapeutic magnetic composition. Also disclosed are methods for administration of the thermotherapeutic magnetic composition. These therapeutic methods may be used where the predetermined target is associated with a disease, such as cancer, diseases of the immune system, pathogen-borne diseases, obesity, hormone-related diseases, Alzheimer's disease, disease precursor, and undesirable materials, such as undesirable adipose tissue, reactions to organ transplants, HIV infected cells, polypeptides receptors, blood clots, and low density lipoproteins.

Thermotherapy via targeted delivery of nanoscale magnetic particles

High-power electromagnetic pulses are of importance in a variety of applications such as transient radar and particle accelerators and when investigating the effect of strong radio-frequency impulses on electronic systems. With all these possibilities in mind, a compact and portable source has been developed by the Plasma and Pulsed Power Group, Loughborough University, U.K., in collaboration with the Defense Science and Technology Laboratory, U.K. The source is based on a pulsed resonant Tesla transformer that produces nanosecond rise-time pulses at voltages exceeding 0.5 MV. In addition to the Tesla transformer, the other major components include a pulse forming line, a high-voltage fast spark gap switch, and a half-wavelength dipole antenna. The pulsed radiated electric field measured at 10 m from the source has a peak amplitude of 12.4 kV/m

A Compact Battery-Powered Half-Megavolt Transformer System for EMP Generation

This paper describes the development of a very efficient computer model for the design and performance prediction of explosive-driven helical generators. The model is based on simple theoretical considerations. Validation of the model is achieved by comparing the theoretical and measured performances of existing both high- and low-energy generators. It is shown that, although the basic model predicts accurately the load current history of high-energy generators, a somewhat more elaborate model is needed for low-energy devices. The model has been used in the design of a simple 1 MJ generator with an eight-section stator coil, intended for use as a current source in an investigation of high-current conditioning systems. A description is given of the construction and testing of this device. Experimental results are in accordance with predictions from the design code and establish that, when primed with 40 kJ at 50 kA from a capacitor bank and using 15 kg of high explosive, the generator is capable of delivering an output of 1 MJ at 7 MA to a coaxial load.

http://iopscience.iop.org/article/10.1088/0022-3727/28/4/027/pdf

Design, construction and testing of explosive-driven helical generators

This paper presents a detailed two-dimensional model for high-voltage air-cored pulse transformers of two quite different designs. A filamentary technique takes magnetic diffusion fully into account and enables the resistances and self and mutual inductances that are effective under fast transient conditions to be calculated. Very good agreement between calculated and measured results for typical transformers has been obtained in several cases, and the model is now regularly used in the design of compact high-power sources.

Fast and accurate two-dimensional modelling of high-current, high-voltage air-cored transformers

This paper describes exploding foil opening and closing switch techniques for use in capacitor bank and flux compressor output conditioning circuits. A simple approach was evolved during an extensive experimental programme, aimed at producing a current pulse with a rise time of a few nanoseconds from the output of a flux compressor (or flux compression generator). Capacitor-based experiments provide data for an empirical model for copper foils, used subsequently in a computer program to predict the results of experiments in which exploding foils are used as both opening and closing switches. The switches operate automatically, thus avoiding the problems of triggering between stages of a conditioning circuit. Data from a 1 MJ flux-compressor exploding-foil opening-switch experiment with a run time of 160 mu s are presented and analysed using the theoretical model.

Fast exploding-foil switch techniques for capacitor bank and flux compressor output conditioning

In this letter, the authors present the inactivation kinetics of cells of Escherichia coli and its mutants following treatment with high-intensity electrical pulses of 700 and 32ns durations. Their experimental results suggest that bacterial inactivation by 700ns pulses is consistent with a mechanism of reversible electroporation, whereas inactivation by 32ns pulses may occur as a result of damage to intracellular components. They believe that their results represent a first step towards elucidating the mechanism of lethality of submicrosecond pulses of different durations in prokaryotes.

Bucur M. Novac

Papers

A Compact Battery-Powered Half-Megavolt Transformer System for EMP Generation

Design, construction and testing of explosive-driven helical generators

Fast and accurate two-dimensional modelling of high-current, high-voltage air-cored transformers

Fast exploding-foil switch techniques for capacitor bank and flux compressor output conditioning

Lethality mechanisms in Escherichia coli induced by intense sub-microsecond electrical pulses