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We present a framework for simulating relaxation dynamics through a conical intersection of an open quantum system that combines methods to approximate the motion of degrees of freedom with disparate time and energy scales. In the vicinity of a conical intersection, a few degrees of freedom render the nuclear dynamics nonadiabatic with respect to the electronic degrees of freedom. We treat these strongly coupled modes by evolving their wavepacket dynamics in the absence of additional coupling exactly. The remaining weakly coupled nuclear degrees of freedom are partitioned into modes that are fast relative to the nonadiabatic coupling and those that are slow. The fast degrees of freedom can be traced out and treated with second-order perturbation theory in the form of the time-convolutionless master equation. The slow degrees of freedom are assumed to be frozen over the ultrafast relaxation, and treated as sources of static disorder. In this way, we adopt the recently developed frozen-mode extension to second-order quantum master equations. We benchmark this approach to numerically exact results in models of pyrazine internal conversion and rhodopsin photoisomerization. We use this framework to study the dependence of the quantum yield on the reorganization energy and the characteristic timescale of the bath, in a two-mode model of photoisomerization. We find that the yield is monotonically increasing with reorganization energy for a Markovian bath, but monotonically decreasing with reorganization energy for a non-Markovian bath. This reflects the subtle interplay between dissipation and decoherence in conical intersection dynamics in the condensed phase.

Using subjective information provided by manager respondents on the stance taken by the works council in company decision making, this paper investigates the association between a measure of works council dissonance or disaffection and plant closings in Germany, 2006-2015. The potential effects of worker representation on plant survivability have been little examined in the firm performance literature because of inadequate information on plant closings on the one hand and having to assume homogeneity of what are undoubtedly heterogeneous worker representation agencies on the other. Our use of two datasets serves to identify failed establishments, while the critical issue of heterogeneity is tackled via manager perceptions of works council disaffection or otherwise. The heterogeneity issue is also addressed by considering the wider collective bargaining framework within which works councils are embedded, and also by allowing for works council learning. It is reported that works council dissonance is positively associated with plant closings, although this association is not found for establishments that are covered by sectoral agreements. Taken in conjunction, both findings are consistent with the literature on the mitigation of rent seeking behavior. Less consistent with the recent empirical literature, however, is the association between plant closings and dissonance over time, that is, from the point at which works council dissonance is first observed. Although the coefficient estimate for dissonance is declining with the length of the observation window, it remains stubbornly positive and highly statistically significant. Finally, there is evidence that establishments with dissonant works councils are associated with a much higher probability of transitioning from no collective bargaining to sectoral bargaining coverage over the sample period than their counterparts with more consensual works councils.

Russia’s aggressive and unconventional actions over the past decade have reinforced NATO's fear of the threat Russia represents to European and global security. Special Operations Forces would seem to have unique applicability when defending against such hybrid tactics, but it has proven difficult for NATO and the academic community to determine the appropriate role of NATO SOF in countering hybrid threats. This is due to a combination of factors: the difficulty of clearly defining the hybrid threat, legal and organizational checks on the use of military internal to national borders, atrophy of useful capabilities due to decreased interoperability and lack of exercise, and a disconnect between developed SOF capabilities and those necessary to be effective in this arena. This thesis lays out a categorized description of observed Russian hybrid tactics. It then identifies NATO SOF's current capabilities that can be matched as counters to elements of the Russian hybrid threat. This includes inherent capabilities as well as those gained by NATO SOF through participation in the ISAF SOF mission in Afghanistan and combat operations in Iraq. Finally, it recommends the NSHQ-assisted formation of Counter Hybrid Threat Joint Interagency Task Forces within NATO member countries, with NSHQ facilitating NATO-wide connectivity and cooperation, along with additional recommendations for research and focus for organizational planning to counter the Russian hybrid threat. http://archive.org/details/counteringthehyb1094561316 Lieutenant Junior Grade, United States Navy Major, United States Army Major, Army, Norway Approved for public release; distribution is unlimited.

State-of-the-art sintering practices for metal injection molded (MIM) nickel superalloys (NiSAs) lead to fine-grain microstructures, reducing creep resistance compared to cast microstructures. MIM uses fine pre-alloyed powders which can increase prior particle boundary (PPB) carbide and oxide formation, restricting grain growth efforts. In the present work, the ability to activate grain growth in a MIM NiSA during supersolidus liquid phase sintering (SLPS) is evaluated using differential scanning calorimetry (DSC). A comparative DSC analysis technique was developed to quantify the SLPS liquid fraction with time and temperature and the grain growth behaviour of the MIM NiSA during SLPS was determined from optical microscopy. SEM-EDS of the sample microstructures revealed that the formation of refractory metal (RM)-Ta mixed MC carbides at the PPB restricts grain growth in the MIM NiSA. Time above the solidus temperature was found to dissolve the RM-Ta mixed MC carbides, enacting grain growth after a short incubation period. The results underscore the difficulty of accessing grain growth under the challenging conditions of MIM while demonstrating that SLPS can increase the grain size in the MIM NiSA.

The oxidation behavior of a fine Ni superalloy (NiSA) powder, Inconel 625, within an alumina support powder during heating has been determined using combined thermogravimetry (TG) and evolved gas analysis (EGA). A gas chromatographic-mass spectrometer (GCMS) was used for EGA. The GCMS was able to semi-quantitatively measure the rate at which air was removed from the furnace due to a He purge, where no pre-evacuation was used. It also was able to measure the effectiveness of a three cycle evacuation and He purge in reducing the oxygen content in the furnace and identify an important alumina off-gassing process that exposed the NiSA powder to H2O and CO2. The parallel use of the TG signal was able to quantitatively determine the relationship between NiSA oxidation and relative concentrations of the oxidizing gases created by the differing furnace pre-conditions and the alumina powder off-gassing process. It was concluded that the developed TG-GCMS method can be widely applied to quantitatively study oxygen pick-up in metal powders under industrially relevant processing conditions.

Master sintering curves (MSCs) were constructed for tape cast NiO, YSZ and NiO/YSZ composite materials using apparent activation energies obtained through dilatometry experiments. A rule of mixtures approach was demonstrated to be a useful analysis tool in understanding the activation energy of the NiO/YSZ composites since NiO and YSZ do not affect the sintering of the other phase. Prediction of the 48 vol% NiO composite was less accurate because of competing sintering modes near the percolation threshold.

Many early adolescents experience peer victimization, but little research has examined how they respond to aggression by peers. Thus, in a large sample of early adolescents (N = 648; M age = 12.96; SD = 0.30; 52.0% female), we examined (1) the associations between peer-reported victimization and self-reported responses to peer provocation, and (2) whether these associations were moderated by peer-reported aggression. In particular, we predicted that the reported use of assertion, a strategy generally viewed as socially skillful, would be associated with less victimization, but only for youth low on peer-reported aggression. Results were consistent with this hypothesis. Moreover, seeking adult intervention was associated with greater victimization for youth high on peer-reported aggression. Implications for research and practice are discussed.

Current data show that patients with haematological malignancies receive 15–20% of the total red blood cells (RBC) transfused annually. The increasing life expectancy and improved treatment and supportive options are changing the demographics of haematology patients receiving transfusions from those that are on chemotherapy to those that require a regular transfusion programme for chronic bone marrow failure, especially myelodysplastic syndromes (MDS).

Linear response approximations are central to our understanding and simulations of nonequilibrium statistical mechanics. Despite the success of these approaches in predicting nonequilibrium dynamics, open questions remain. Laird and Thompson [J. Chem. Phys. 126, 211104 (2007)] previously formalized, in the context of solvation dynamics, the connection between the static linear-response approximation and the assumption of Gaussian statistics. The Gaussian statistics perspective is useful in understanding why linear response approximations are still accurate for perturbations much larger than thermal energies. In this paper, we use this approach to address three outstanding issues in the context of the "dipole-flip" model, which is known to exhibit nonlinear response. First, we demonstrate how non-Gaussian statistics can be predicted from purely equilibrium molecular dynamics (MD) simulations (i.e., without resort to a full nonequilibrium MD as is the current practice). Second, we show that the Gaussian statistics approximation may also be used to identify the physical origins of nonlinear response residing in a small number of coordinates. Third, we explore an approach for correcting the Gaussian statistics approximation for nonlinear response effects using the same equilibrium simulation. The results are discussed in the context of several other examples of nonlinear responses throughout the literature.

This paper discusses the development of a testbed for real-time experimental studies of time-modulated arrays. The proposed architectural design will be described, and the current state of progress will be presented through simulation and over-the-air tests conducted in a lab. The TMA antennas and radios are designed to operate at about 2.3 GHz for a target application of passive radar using XM Radio, in which the TMA capabilities will be targeted at multibeaming and interference suppression.

Wilderness therapy is a specialized approach to adolescent substance use and mental health treatment. While empirical evidence of positive outcomes grows to support this approach, qualitative understandings are lacking in the literature, thereby limiting theoretical explanations. Additionally, the voice of adolescent clients is hardly present, and was therefore the focus for this research. A sample of 148 adolescent wilderness therapy clients at one Canadian residential treatment program for addictive behaviour and mental health issues participated in the study. A realist approach utilizing thematic analysis of written open-ended responses produced six major themes; three depicting participant experiences (social dynamics, wilderness, catalyst for change) and three for perceived outcomes (skill development, self-concept, health). These findings are discussed in relationship to the development of a clinical model of wilderness therapy and the potential of wilderness interventions in adolescent residential treatment. Recommendations for practice and future research are discussed.

We present a theory and accompanying importance sampling method for computing rate constants in spatially inhomogenious systems. Using the relationship between rate constants and path space partition functions, we illustrate that the relative change in the rate of a rare event through space is isomorphic to the calculation of a free energy difference, albeit in a trajectory ensemble. Like equilibrium free energies, relative rate constants can be estimated by importance sampling. An extension to transition path sampling is proposed that combines biased path ensembles and weighted histogram analysis to accomplish this estimate. We show that rate constants can also be decomposed into different contributions, including relative changes in stability, barrier height and flux. This decomposition provides a means of interpretation and insight into rare processes in complex environments. We verify these ideas with a simple model of diffusion with spatially varying diffusivity and illustrate their utility in an atomistic model of ion pair dissociation near an electrochemical interface., 5 pages 2 Figures; Small revisions, to appear in JCP 2019

We present a method to study rare nonadiabatic dynamics in open quantum systems using transition path sampling and quantum jump trajectories. As with applications of transition path sampling to classical dynamics, the method does not rely on prior knowledge of transition states or reactive pathways, and thus can provide mechanistic insight into ultrafast relaxation processes in addition to their associated rates. In particular, we formulate a quantum path ensemble using the stochastic realizations of an unravelled quantum master equation, which results in trajectories that can be conditioned on starting and ending in particular quantum states. Because the dynamics rigorously obeys detailed balance, rate constants can be evaluated from reversible work calculations in this conditioned ensemble, allowing for branching ratios and yields to be computed in an unbiased manner. We illustrate the utility of this method with three examples: energy transfer in a donor-bridge-acceptor model, and models of photo-induced proton-coupled electron transfer and thermally activated electron transfer. These examples demonstrate the efficacy of path ensemble methods and pave the way for their use in studying of complex reactive quantum dynamics.

Owing to the outstanding near-infrared (NIR) optical properties, phthalocyanines (Pc) have promising potential as theranostic agents for fluorescence image-guided drug delivery and noninvasive treatment of deep tumors by photodynamic therapy (PDT). Nevertheless, clinical application of phthalocyanines is substantially limited by poor water solubility, aggregation and insufficient selectivity for cancer cells. To address these issues, we have developed a novel dendrimer-based theranostic platform for tumor-targeted delivery of phthalocyanines. The preparation procedure involved the modification of the Pc molecule with a hydrophobic linker, which significantly enhances physical encapsulation of the hydrophobic drug into a generation 4 polypropylenimine (PPI G4) dendrimer. In order to improve biocompatibility and tumor-targeted delivery, the surface of the resulting Pc-PPIG4 complexes was additionally modified with poly(ethylene glycol) (PEG) and luteinizing hormone-releasing hormone (LHRH) peptide, respectively. The developed nanocarriers have an average diameter of 62.3 nm and narrow size distribution with a polydispersity index of 0.100. The drug encapsulation efficiency was 20% w/w, and the synthesized phthalocyanine derivative entrapped in the dendrimer-based nanocarrier exhibits a distinct NIR absorption (700 nm) and fluorescence emission (710 and 815 nm), required for an efficient PDT and fluorescence imaging. It was demonstrated that subcellular localization in vitro and organ distribution in vivo of the developed nanocarrier can be determined based on the intrinsic fluorescence properties of encapsulated phthalocyanine, validating its role as an imaging agent. The imaging experiments revealed that the LHRH targeted nanocarrier is capable of an efficient internalization into cancer cells as well as tumor accumulation when intravenously administered into mice. Finally, the prepared formulation exhibited low dark cytotoxicity (IC50=28 μg/mL) while light irradiation of the cancer cells transfected with the developed theranostic agents resulted in significant PDT effects (IC50=0.9 μg/mL) through excessive generation of toxic reactive oxygen species. Thus, the obtained results demonstrated significant potential of the designed dendrimer-based nanocarrier as an efficient NIR theranostic agent.