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The design and optimization of laser-Compton x-ray systems based on compact distributed charge accelerator structures can enable micron-scale imaging of disease and the concomitant production of beams of Very High Energy Electrons (VHEEs) capable of producing FLASH-relevant dose rates. The physics of laser-Compton x-ray scattering ensures that the scattered x-rays follow exactly the trajectory of the incident electrons, thus providing a route to image-guided, VHEE FLASH radiotherapy. The keys to a compact architecture capable of producing both laser-Compton x-rays and VHEEs are the use of X-band RF accelerator structures which have been demonstrated to operate with over 100 MeV/m acceleration gradients. The operation of these structures in a distributed charge mode in which each radiofrequency (RF) cycle of the drive RF pulse is filled with a low-charge, high-brightness electron bunch is enabled by the illumination of a high-brightness photogun with a train of UV laser pulses synchronized to the frequency of the underlying accelerator system. The UV pulse trains are created by a patented pulse synthesis approach which utilizes the RF clock of the accelerator to phase and amplitude modulate a narrow band continuous wave (CW) seed laser. In this way it is possible to produce up to 10 μA of average beam current from the accelerator. Such high current from a compact accelerator enables production of sufficient x-rays via laser-Compton scattering for clinical imaging and does so from a machine of "clinical" footprint. At the same time, the production of 1000 or greater individual micro-bunches per RF pulse enables > 10 nC of charge to be produced in a macrobunch of < 100 ns. The design, construction, and test of the 100-MeV class prototype system in Irvine, CA is also presented.

Enthalpies and free energies were calculated for different monomolecular dissociations of sulfur mustard using G2(MP2) theory. The results indicate that it may not be viable for this chemical warfare agent to undergo noncatalytic thermal destruction at temperatures up to at least 1800 K. More appropriate high-temperature decomposition pathways involve C-C an C-S bond cleavages. Operating conditions exceeding 2000 K appear to be a requirement for environmentally robust decomposition/destruction.

Maurice Merlau-Ponty follows Hegel's philosophy of history to some extent, but he also criticizes Hegel and develops his own conception of history. Merleau-Ponty agrees with Hegel's idea of history as rational. His criticisms concern Hegel's reification of reason, his methodological attempt to go beyond the limits of human understanding, and his belief in historical necessity. Merleau-Ponty instead suggests that events are radically contingent.

Catalytic extraction processing is an innovative technology for the conversion of potentially hazardous organic, organometallic, inorganic and ash waste streams into useful and marketable commercial products. It has been validated by the EPA as a technology that meets and even surpasses its waste treatment standards. The technology involves the injection of feed materials into a molten metal bath where dissociation of molecular entities to their elements and product formation occur.

Antimicrobial resistance is a growing global concern in human and veterinary medicine, with an ever-increasing void in the arsenal of clinicians. Novel classes of compounds including carbon monoxoide-releasing molecules (CORMs), for example the light-activated metal complex [Mn(CO)3(tpa-κ3N)]Br, could be used as alternatives/to supplement traditional antibacterials. Avian pathogenic Escherichia coli (APEC) represent a large reservoir of antibiotic resistance and can cause serious clinical disease in poultry, with potential as zoonotic pathogens, due to shared serotypes and virulence factors with human pathogenic E. coli. The in vitro activity of [Mn(CO)3(tpa-κ3N)]Br against multidrug-resistant APECs was assessed via broth microtitre dilution assays and synergy testing with colistin performed using checkerboard and time-kill assays. In vivo antibacterial activity of [Mn(CO)3(tpa-κ3N)]Br alone and in combination with colistin was determined using the Galleria mellonella wax moth larvae model. Animals were monitored for life/death, melanisation and bacterial numbers enumerated from larval haemolymph. In vitro testing produced relatively high [Mn(CO)3(tpa-κ3N)]Br minimum inhibitory concentrations (MICs) of 1024 mg/L. However, its activity was significantly increased with the addition of colistin, bringing MICs down to ≤32 mg/L. This synergy was confirmed in time-kill assays. In vivo assays showed that the combination of [Mn(CO)3(tpa-κ3N)]Br with colistin produced superior bacterial killing and significantly increased larval survival. In both in vitro and in vivo assays light activation was not required for antibacterial activity. This data supports further evaluation of [Mn(CO)3(tpa-κ3N)]Br as a potential agent for treatment of systemic infections in humans and animals, when used with permeabilising agents such as colistin. [ABSTRACT FROM AUTHOR]

The article features the black widow spiders of the genus Latrodectus of the cobweb spider family Theridildae of suborder Araneomorphae. It provides a characteristic description of the venomous genus, distinguishing it from spiders of the genus Steatoda or false black widows. It notes that keeping venomous spiders including Latrodectus is illegal in some places. It offers advice on captive maintenance including housing materials, environment and diet. It details the habitat of some species, breeding behavior, and venom and bite symptoms.