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In this paper we report a combined experimental and theoretical study on the dynamics of the prototype insertion reaction C1D H2. Product angular and velocity distributions have been obtained in crossed beam experiments at two collision energies of 7.8 and 16.0 kJ mol−1. Quasiclassical trajectory QCT and quantum mechanical QM scattering calculations have been carried out on a recent accurate ab initiopotential energy surface at the energies of the experiments. The molecular beam results have been simulated using the theoretical calculations. Reasonably good agreement between experiment and theory is found.

Ototoxicity continues to be a major dose-limiting side effect of cis-diamminedichloroplatinum(II) (cisplatin). With an ongoing need to develop pharmaceutical protection strategies for cisplatin’s ototoxicity, there is also a need to develop stable in-vivo mammalian models of cisplatin ototoxicity. The current study examined the difference in ototoxicity of a cumulative 12 mg/kg dose of cisplatin in the Fischer 344/NHsd rat when administered over four different dosing protocols. Hearing sensitivity was measured using free-field auditory brainstem response thresholds under anesthesia. Rats were divided into four groups. The first group was administered 12 mg/kg of cisplatin in a single bolus infusion. The second group was administered two 6 mg/kg infusions separated by 7 days. The third group was administered 3 mg/kg injections once per day for 4 consecutive days. The fourth group was administered 3 mg/kg injections in four injections separated by 3 days each. Hearing thresholds and body weights were measured at 3 and 7 days after the final cisplatin exposure. Postmortem sensory cell counts were used to confirm injury to the auditory system. The 4 consecutive days of 3 mg/kg induced a greater mortality rate and greater hearing loss at day 3 than the other experimental protocols. The 3 mg/kg administered every 3 days induced less sensory cell loss than the other conditions. The findings indicate that 4 consecutive days of 3 mg/kg cisplatin is not a viable ototoxicity model in the Fischer 344/NHsd rat, but that the other models are all effective in inducing comparable cochlear injuries.

The Florida mottled duck (Anas fulvigula fulvigula) is threatened by introgression through hybridization with feral mallards (A. platyrhynchos). An essential component in managing this threat is the ability to accurately distinguish mottled ducks from mallards and hybrids in the wild. We provide a genetically cross‐validated phenotype key that accurately identifies mottled ducks. We collected data on structural and plumage traits from museum specimens of Florida, USA, mottled ducks and mallards to identify morphological traits useful in this process. We performed extensive comparisons and discriminant function analysis to identify traits informative in distinguishing the 2 species. We used these traits to preliminarily assign 168 contemporary birds as putative mottled duck, mallard, or hybrid. We collected tissue samples from each contemporary specimen and amplified and genotyped associated DNA. We used microsatellite markers to determine posteriorprobability species assignments for the 168 specimens. We then performed recursive partitioning of phenotypic traits and posteriorgenotype assignments to create identification keys based on the most informative traits separating mottled ducks from mallards and hybrids. Finally, we cross‐validated the keys by comparing assignments made using the key to those from genotyping for 339 wild ducks. The keys were >90% accurate, which suggests that their adoption will increase the ability of managers to address the threat of hybridization by mallards by allowing mottled ducks to be distinguished from other ducks in Florida. Our research provides a methodology to develop genetically cross‐validated identification keys for other species threatened by genetic introgression. © 2016 The Wildlife Society.

Porous back-end dielectric materials with porosity ranging from 8% to 25% have been characterized in terms of their resistive switching behavior. The porous dielectric is sandwiched between Cu and W or Pt electrodes. Some metal-insulator-metal structures have a 2 nm SiCN diffusion barrier at either electrode or at both electrodes. 90% of samples are intrinsically conductive due to strong Cu doping of the dielectric. About 10% of the samples display resistive switching behavior, of which devices with two SiCN barriers can be switched repeatedly, demonstrating that resistive switching in porous dielectrics is feasible. The forming voltage of the filaments increases with increasing porosity of the dielectric. Depending on the voltage polarity, Cu and oxygen vacancy conductive filaments can be formed. The properties of resistive switching established in this work provide a solid basis for further improvement of ReRAM devices based on porous dielectrics compatible with CMOS backend.

Porous back-end dielectric materials with porosity from 8% to 25%, sandwiched between Cu and W/Pt electrodes, have been investigated in terms of Cu diffusivity and mobility. In nonporous materials the diffusivity D and mobility m of charged particles such as an ion is related by the Einstein relation: u=D q/kT. Here, we present evidence that in porous materials the diffusivity and mobility are decoupled on a global scale, even though the Einstein relation still holds locally. In porous materials, the voids lying in the path of the ion present an impenetrable barrier for ion migration. Voids can be only overcome by a detour around the obstacle by virtue of diffusion. We propose a modified relation between diffusivity and mobility in porous materials by u=fp[?]D q/kT where a porosity-tortuosity factor fp <1 is introduced. The factor fp depends on porosity and tortuosity of the porous material.

La maladie des griffes du chat est une affection polymorphe, pouvant se manifester par des atteintes ophtalmologiques isolées. Nous rapportons les observations cliniques de sept cas, ayant présenté une atteinte ophtalmologique postérieure de la maladie des griffes du chat.

Letters to the editor are presented in response to articles in the September 2015 issue that include "Velociraptor," "Mudskippers," and "Quiet Storm."

The effects of oxygen plasma treatment on molecular structures at low-korganosilicate (SiCOH) film surfaces and buried interfaces were investigated using sum frequency generation (SFG) vibrational spectroscopy and Raman spectroscopy. SFG and Raman spectra were acquired from pristine and plasma-treated low-kSiCOH films to characterize the interfacial and bulk molecular structures of the films before and after plasma treatment. Two SiCOH films with similar molecular structures but different porosities were investigated to correlate the effects of plasma treatment to the porosity of low-kfilms. SFG spectra indicated that the surface molecular structure of dense SiCOH films was more resistant to plasma damage than the surface molecular structure of porous SiCOH films. Furthermore, the ratio of SFG peak intensities before and after plasma treatment enabled quantification of methyl depletion at the surface of SiCOH films after plasma treatment. The molecular structure at buried Si/SiCOH interfaces was characterized by simulating SFG spectra from pristine and plasma-treated SiCOH films. SFG spectra from plasma-treated low-kfilms were simulated by adjusting the methyl orientation and number density parameters at the low-k/air interface to match experimental results. Simulated SFG spectra indicated that methyl groups at the buried interface of both dense and porous SiCOH films were oriented with a high tilt angle before and after plasma treatment. The developed methodology is general and can be extended to characterize the effects of many different plasma treatments, wet chemical treatments, and surface repair treatments on the interfacial molecular structures of many polymer or organic films.