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We combine ab initio molecular electronic Hamiltonians with a cavity quantum electrodynamics model for dissipative photonic modes and apply mean-field theories to the ground- and excited-states of resulting polaritonic systems. In particular, we develop a non-Hermitian configuration interaction singles theory for mean-field ground- and excited-states of the molecular system strongly interacting with a photonic mode and apply these methods to elucidating the phenomenology of paradigmatic polaritonic systems. We leverage the Psi4Numpy framework to yield open-source and accessible reference implementations of these methods.

The influence of external dielectric environments is well understood for 2D semiconductor materials but is overlooked for colloidally-grown II-VI nanoplatelets (NPLs). In this work, we synthesize MX (M=Cd, Hg; X= Se, Te) NPLs of varying thicknesses, and apply a modified Elliott model to fit excitonic absorption features and report exciton binding energies for cadmium telluride and mercury chalcogenides for the first time. Our observations indicate that the exciton binding energy is modulated by the dielectric screening of semiconductor material by the external ligand environment. Furthermore, NPL binding energies show a dependence on the number of monolayers consistent with relative effect of internal vs. external dielectric. To describe this, we derive an analytical electrostatic model, reinforcing the hypothesis that the external environment increases the exciton binding energy relative to the bulk—due to the distortion of the Coulombic potential across the NPL surface. We further confirm this effect by decreasing and recovering the exciton binding energy of HgTe NPLs through washing in polarizable solvents. Our results illustrate that NPLs are colloidal analogues of Van der Waals 2D semiconductors and point to surface modification as an approach to control photophysics and device properties.

We present a non-Hermitian formulation of the polaritonic structure of azobenzene strongly coupled to a photonic mode that explicitly accounts for the fleeting nature of the photon-molecule interaction. This formalism reveals that the polaritonic non-adiabatic couplings that facilitate the cis-trans isomerization can be dramatically modified by the inclusion of the photonic dissipation into the polaritonic Hamiltonian. We perform Fewest-Switches Surface Hopping dynamics on the surfaces that derive from our non-Hermitian formalism and find that the polaritonic isomerization rates are strongly suppressed for moderate to large photon dissipation rates. These findings highlight the important role that the nite lifetime of photonic degrees of freedom play in polaritonic chemistry.

Photographs of a handful of the 46 million specimens in the archives of the California Academy of Sciences. Jonathan Foley argues that museums like the Academy have a responsibility to curate and preserve collections in order to document and understand the changing nature of life on Earth, and to help build the tools we need to ultimately sustain the wonderful creatures and ecosystems that share our planet.

This paper reviews the effect of a primary care financing scheme introduced in New Zealand as a component of the New Zealand Primary Health Care Strategy, a comprehensive reform of the way that primary healthcare was governed, financed and delivered. The population-based funding formulae incorporated an area-based measure of social deprivation and ethnicity in an explicit attempt to improve access to care for certain population groups and fund social interventions aimed at addressing conditions that lead to improved health outcomes. The New Zealand experience shows that introducing a nationwide, comprehensive program to improve access and reduce health disparities is possible. However, the effect of this effort on reducing health disparities is not entirely clear because success ultimately relies on local implementation of a complex set of interventions that need to be evaluated more rigorously. In addition, the partial subsidies for first contact care that came with the Strategy have been shown to improve access, but, the success of this approach relies on compliance by private-practising general practitioners with a fee reduction regimen, which is subject to local variation.

A set of 723 high-quality human core promoter sequences were compiled and analyzed for overrepresented motifs. Beside the two well-characterized core promoter motifs (TATA and Inr), several known motifs (YY1, Sp1, NRF-1, NRF-2, CAAT, and CREB) and one potentially new motif (motif8) were found. Interestingly, YY1 and motif8 mostly reside immediately downstream from the TSS. In particular, the YY1 motif occurs primarily in genes with 5′-UTRs shorter than 40 base pairs (bp) and its locations coincide with the translation start site. We verified that the YY1 motif is bound by YY1 in vitro. We then performed detailed analysis on YY1 chromatin immunoprecipitation data with a whole-genome human promoter microarray (ChIP-chip) and revealed that the thus identified promoters in HeLa cells were highly enriched with the YY1 motif. Moreover, the motif overlapped with the translation start sites on the plus strand of a group of genes, many with short 5′-UTRs, and with the transcription start sites on the minus strand of another distinct group of genes; together, the two groups of genes accounted for the majority of the YY1-bound promoters in the ChIP-chip data. Furthermore, the first group of genes was highly enriched in the functional categories of ribosomal proteins and nuclear-encoded mitochondria proteins. We suggest that the YY1 motif plays a dual role in both transcription and translation initiation of these genes. We also discuss the evolutionary advantages of housing a transcriptional element inside the transcript in terms of the migration of these genes in the human genome.

ObjectiveTo investigate whether an intensive early rheumatoid arthritis (RA) treat-to-target (T2T) strategy could be improved through the use of musculoskeletal ultrasound (MSUS) assessment of disease activity.Methods111 newly diagnosed patients with RA or undifferentiated arthritis (symptom duration ResultsGroups were matched for baseline clinical, demographic and radiographic features. The intervention group received more intensive DMARD therapy. Both groups demonstrated significant improvements in DAS44 (mean change: control −2.58, intervention −2.69; 95% CI difference between groups −0.70 to 0.48; p=0.72). There were no significant between-group differences for any ACR core-set variables, except DAS44 remission after 18 months (control 43%, intervention 66%; p=0.03). There was minimal progression of MRI and radiographic erosions and no difference in imaging outcomes or serious adverse event rates.ConclusionsIn early RA, a MSUS-driven T2T strategy led to more intensive treatment, but was not associated with significantly better clinical or imaging outcomes than a DAS28-driven strategy.Trial registration numberNCT00920478.