Todd H. Rider

A general critique of inertial-electrostatic confinement fusion systems

The suitability of various implementations of inertial‐electrostatic confinement (IEC) systems for use as D–T, D–D, D–3He, 3He–3He, p–11B, and p–6Li reactors has been examined, and several fundamental flaws in the concept have been discovered. Bremsstrahlung losses for all of these fuels have been calculated in a general fashion which applies not only to IEC systems but also to most other fusion schemes; these calculations indicate that bremsstrahlung losses will be prohibitively large for 3He–3He, p–11B, and p–6Li reactors and will be a considerable fraction of the fusion power for D–3He and D–D reactors. Further calculations show that it does not appear possible for the dense central region of a reactor‐grade IEC device to maintain significantly non‐Maxwellian ion distributions or to keep two different ion species at significantly different temperatures, in contradiction with earlier claims made about such systems. Since the ions form a Maxwellian distribution with a mean energy not very much smaller th...

Broad-Spectrum Antiviral Therapeutics

Currently there are relatively few antiviral therapeutics, and most which do exist are highly pathogen-specific or have other disadvantages. We have developed a new broad-spectrum antiviral approach, dubbed Double-stranded RNA (dsRNA) Activated Caspase Oligomerizer (DRACO) that selectively induces apoptosis in cells containing viral dsRNA, rapidly killing infected cells without harming uninfected cells. We have created DRACOs and shown that they are nontoxic in 11 mammalian cell types and effective against 15 different viruses, including dengue flavivirus, Amapari and Tacaribe arenaviruses, Guama bunyavirus, and H1N1 influenza. We have also demonstrated that DRACOs can rescue mice challenged with H1N1 influenza. DRACOs have the potential to be effective therapeutics or prophylactics for numerous clinical and priority viruses, due to the broad-spectrum sensitivity of the dsRNA detection domain, the potent activity of the apoptosis induction domain, and the novel direct linkage between the two which viruses have never encountered.

Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium

Analytical Fokker–Planck calculations are used to accurately determine the minimum power that must be recycled in order to maintain a plasma out of thermodynamic equilibrium despite collisions. For virtually all possible types of fusion reactors in which the major particle species are significantly non-Maxwellian or are at radically different mean energies, this minimum recirculating power is substantially larger than the fusion power. Barring the discovery of methods for recycling the power at exceedingly high efficiencies, grossly nonequilibrium reactors will not be able to produce net power.

Effects of path-length errors on external-cavity semiconductor laser arrays

The frequency locking range of a laser diode array was experimentally determined. A one-dimensional array of seven lasers was phase-locked by placing it in an external optical cavity to establish coupling between the lasers. It was found that the experimental frequency locking range was four times greater than the theoretical locking range. The large experimental locking range demonstrates that there appears to be a greater tolerance of path-length errors in phase-locked laser arrays than the theory had earlier implied.

Modification of classical Spitzer ion–electron energy transfer rate for large ratios of ion to electron temperatures

Corrections to the classical Spitzer heat transfer rate between ions and electrons are calculated for the case when the ion temperature Ti is significantly higher than the electron temperature Te. It is found that slow electrons are partially depleted by their interactions with the ions, resulting in a decrease in the heat transfer in comparison with the Spitzer rate, which assumes perfectly Maxwellian electrons. The heat transfer steadily decreases from the classical value as Ti/Te increases; for Ti/Te values of several hundred, the heat transfer rate drops to around 60%–80% of the Spitzer result. A useful expression for the heat transfer correction factor in the case when all of the ion species are at the temperature Ti is found to be Pie/(Pie)Spitzer ≊[1+(me/mi)(Ti/Te)]3/2 exp{−[3.5∑i (Z2ini/ne)(me/mi) (Ti/Te)]2/3}. This expression is quite accurate for values of ∑i (Z2ini/ne)(mp/mi)(Ti/Te) less than about 50 (where mp is the proton mass), although it underestimates the heat transfer rate for larger va...