Vibrational Exciton Density of States in Solid Benzene

Computer‐aided calculations, based on experimentally‐fitted pairwise interaction terms, give the complete exciton density‐of‐states profile for the entire Brillouin zone. The restricted Frenkel model, with short‐range interactions, is the key assumption. Results are given and discussed for the out‐of‐plane a2ua2u normal mode ν11ν11(C6H6 and C6D6), for ν12(b1u)ν12(b1u), and for ν15(b2u)ν15(b2u). The wide range of parameters used makes this investigation pertinent to other vibrational and electronic exciton bands of benzene and any other molecular crystal with the same interchange symmetry. Also, Van Hove singularities are found to be more important for symmetry‐based critical points than for “accidental” critical points. Present‐day experimental and theoretical intermolecular excitation exchange interaction terms are compared.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71006/2/JCPSA6-53-9-3674-1.pd

Evaluation of a Technology-Based Survivor Care Plan for Breast Cancer Survivors: Pre-Post Pilot Study.

BACKGROUND: As of 2016, almost 16 million individuals were cancer survivors, including over 3.5 million survivors of breast cancer. Because cancer survivors are living longer and have unique health care needs, the Institute of Medicine proposed a survivor care plan as a way to alleviate the many medical, emotional, and care coordination problems of survivors. OBJECTIVE: This pilot study for breast cancer survivors was undertaken to: (1) examine self-reported changes in knowledge, confidence, and activation from before receipt to after receipt of a survivor care plan; and (2) describe survivor preferences for, and satisfaction with, a technology-based survivor care plan. METHODS: A single group pretest-posttest design was used to study breast cancer survivors in an academic cancer center and a community cancer center during their medical visit after they completed chemotherapy. The intervention was a technology-based survivor care plan. Measures were taken before, immediately after, and 1 month after receipt of the survivor care plan. RESULTS: A total of 38 breast cancer survivors agreed to participate in the study. Compared to baseline levels before receipt of the survivor care plan, participants reported increased knowledge both immediately after its receipt at the academic center (P\u3c.001) and the community center (P\u3c.001) as well as one month later at the academic center (P=.002) and the community center (P\u3c.001). Participants also reported increased confidence immediately following receipt of the survivor care plan at the academic center (P=.63) and the community center (P=.003) and one month later at both the academic center (P=.63) and the community center (P\u3c.001). Activation was increased from baseline to post-survivor care plan at both the academic center (P=.05) and community center (P\u3c.001) as well as from baseline to 1-month follow-up at the academic center (P=.56) and the community center (P\u3c.001). Overall, community center participants had lower knowledge, confidence, and activation at baseline compared with academic center participants. Overall, 22/38 (58%) participants chose the fully functional electronic survivor care plan. However, 12/23 (52%) in the community center group chose the paper version compared to 4/15 (27%) in the academic center group. Satisfaction with the format (38/38 participants) and the content (37/38 participants) of the survivor care plan was high for both groups. CONCLUSIONS: This study provides evidence that knowledge, confidence, and activation of survivors were associated with implementation of the survivor care plan. This research agrees with previous research showing that cancer survivors found the technology-based survivor care plan to be acceptable. More research is needed to determine the optimal approach to survivor care planning to ensure that all cancer survivors can benefit from it

Development of tuneable Fabry-Perot sensors for parallelised photoacoustic signal acquisition

Fabry-Pérot (FP) sensors have enabled high resolution 3D photoacoustic (PA) imaging in backward mode. However, raster-scanning of the interrogation laser beam across the sensor can result in slow 3D image acquisition. To overcome this limitation, parallelized PA signal acquisition can be used for which FP sensors with uniform optical thickness are required. In this work, the optical thickness is tuned a) irreversibly through the use of a photopolymer host matrix and b) actively using embedded electro-optic (EO) chromophores. Polymer spacers (5 μm) were deposited using spin coating and sandwiched between two dielectric mirrors and transparent ITO electrodes. The employed polymer guest-host system consists of an EO chromophore (2-methyl-4-nitroaniline) and poly(vinyl cinnamate). EO tuneability was induced using contact poling and a tuneability of 68 pm was demonstrated. The optical thickness was homogenised by raster scanning a UV beam whilst varying the exposure time across a 4 mm2 detection aperture

Development of a backward-mode photoacoustic microscope using a Fabry-Perot sensor

Optical-resolution photoacoustic microscopy (PAM) has been shown to enable the acquisition of high resolution (μm) functional and anatomical images. For backward-mode operation, conventional piezoelectric ultrasound transducers need to be placed far away from the signal source due to their opacity and size. This can result in reduced acoustic sensitivity. Planar Fabry-Perot polymer film interferometer (FPI) sensors have the potential to overcome this limitation since they are transparent to the excitation wavelength, can be placed immediately adjacent to the signal source for high acoustic sensitivity, and offer a broadband frequency response (0 –50 MHz). In this study, we present a high frame rate, backward-mode OR-PAM system based on a planar FPI ultrasound sensor. A ns-pulsed laser provides excitation pulses (<200 nJ, maximum pulse repetition frequency = 200 kHz, 532 nm) to generate photoacoustic waves that are detected using a planar FPI sensor interrogated at 765-781 nm. For backwardmode operation and highest acoustic sensitivity, the excitation and interrogation beams are coaxially aligned and rasterscanned. The optical transfer function of the sensor, the spatial resolution and the detection sensitivity were determined to characterise the set-up. Images of a leaf phantom and first in vivo images of zebrafish larvae were acquired. This approach will enable fast 3D OR-PAM with high resolution and high sensitivity for functional and molecular imaging applications. FPI-based ultrasound detection also has the potential to enable dual-mode optical- and acousticresolution PAM and the integration of photoacoustic imaging with purely optical modalities such as multi-photon microscopy

The exponential map for the unitary group SU(2,2)

In this article we extend our previous results for the orthogonal group, $SO(2,4)$, to its homomorphic group $SU(2,2)$. Here we present a closed, finite formula for the exponential of a $4\times 4$ traceless matrix, which can be viewed as the generator (Lie algebra elements) of the $SL(4,C)$ group. We apply this result to the $SU(2,2)$ group, which Lie algebra can be represented by the Dirac matrices, and discuss how the exponential map for $SU(2,2)$ can be written by means of the Dirac matrices.Comment: 10 page

A Cluster-Matching-Based Method for Video Face Recognition

Face recognition systems are present in many modern solutions and thousands of applications in our daily lives. However, current solutions are not easily scalable, especially when it comes to the addition of new targeted people. We propose a cluster-matching-based approach for face recognition in video. In our approach, we use unsupervised learning to cluster the faces present in both the dataset and targeted videos selected for face recognition. Moreover, we design a cluster matching heuristic to associate clusters in both sets that is also capable of identifying when a face belongs to a non-registered person. Our method has achieved a recall of 99.435% and a precision of 99.131% in the task of video face recognition. Besides performing face recognition, it can also be used to determine the video segments where each person is present.Comment: 13 page

A validation of the Oswestry Spinal Risk Index

Purpose The purpose of this study was to validate the Oswestry Spinal Risk Index (OSRI) in an external population. The OSRI predicts survival in patients with metastatic spinal cord compression (MSCC). Methods We analysed the data of 100 patients undergoing surgical intervention for MSCC at a tertiary spinal unit and recorded the primary tumour pathology and Karnofsky performance status to calculate the OSRI. Logistic regression models and survival plots were applied to the data in accordance with the original paper. Results Lower OSRI scores predicted longer survival. The OSRI score predicted survival accurately in 74% of cases (p = 0.004). Conclusions Our study has found that the OSRI is a significant predictor of survival at levels similar to those of the original authors and is a useful and simple tool in aiding complex decision making in patients presenting with MSC

A study of compliance post-OFT infringement action

This article considers compliance with competition law among a particular sub-set of UK companies. The research was principally motivated by the reform of UK competition law in the late 1990's and the introduction of new investigatory and fining powers for the UK competition authorities, with potentially very serious consequences for companies in breach of competition law. There has been fairly extensive research into competition law compliance in Australia, and in particular, a Report based on a recent ACCC Enforcement and Compliance Survey noted that:- 'Those who have interacted with or been investigated by the ACCC generally report themselves to be more compliant.' Accordingly, in this research we sought to ascertain the extent to which an infringement finding by the OFT altered awareness of, attitudes to, and methods of compliance with competition law. This was undertaken by forwarding a questionnaire to all parties which were the subject of an infringement decision by the OFT under the Competition Act 1998. The research considers the extent to which competition law compliance, and the motivations for instituting an effective compliance programme, have been affected by enforcement action by the Office of Fair Trading under the Competition Act 1998

Glacial controls on redox-sensitive trace element cycling in Arctic fjord sediments (Spitsbergen, Svalbard)

Glacial meltwater is an important source of bioessential trace elements to high latitude oceans. Upon delivery to coastal waters, glacially sourced particulate trace elements are processed during early diagenesis in sediments and may be sequestered or recycled back to the water column depending on local biogeochemical conditions. In the glaciated fjords of Svalbard, large amounts of reactive Fe and Mn (oxyhydr)oxides are delivered to the sediment by glacial discharge, resulting in pronounced Fe and Mn cycling concurrent with microbial sulfate reduction. In order to investigate the diagenetic cycling of selected trace elements (As, Co, Cu, Mo, Ni, and U) in this system, we collected sediment cores from two Svalbard fjords, Van Keulenfjorden and Van Mijenfjorden, in a transect along the head-to-mouth fjord axis and analyzed aqueous and solid phase geochemistry with respect to trace elements, sulfur, and carbon along with sulfate reduction rates. We found that Co and Ni associate with Fe and Mn (oxyhydr)oxides and enter the pore water upon reductive metal oxide dissolution. Copper is enriched in the solid phase where sulfate reduction rates are high, likely due to reactions with H2S and the formation of sulfide minerals. Uranium accumulates in the solid phase likely following reduction by both Fe- and sulfate-reducing bacteria, while Mo adsorbs to Fe and Mn (oxyhydr)oxides in the surface sediment and is removed from the pore water at depth where sulfidization makes it particle-reactive. Arsenic is tightly coupled to Fe redox cycling and its partitioning between solid and dissolved phases is influenced by competition with FeS for adsorption sites on crystalline Fe oxides. Differences in trace element cycling between the two fjords suggest delivery of varying amount and composition of tidewater glacier (Van Keulenfjorden) and meltwater stream (Van Mijenfjorden) material, likely related to oxidative processes occurring in meltwater streams. This processing produces a partially weathered, more reactive sediment that is subject to stronger redox cycling of Fe, Mn, S, and associated trace elements upon delivery to Van Mijenfjorden. With climate warming, the patterns of trace element cycling observed in Van Mijenfjorden may also become more prevalent in other Svalbard fjords as tidewater glaciers retreat into meltwater stream valleys

Differential Forms on Log Canonical Spaces

The present paper is concerned with differential forms on log canonical varieties. It is shown that any p-form defined on the smooth locus of a variety with canonical or klt singularities extends regularly to any resolution of singularities. In fact, a much more general theorem for log canonical pairs is established. The proof relies on vanishing theorems for log canonical varieties and on methods of the minimal model program. In addition, a theory of differential forms on dlt pairs is developed. It is shown that many of the fundamental theorems and techniques known for sheaves of logarithmic differentials on smooth varieties also hold in the dlt setting. Immediate applications include the existence of a pull-back map for reflexive differentials, generalisations of Bogomolov-Sommese type vanishing results, and a positive answer to the Lipman-Zariski conjecture for klt spaces.Comment: 72 pages, 6 figures. A shortened version of this paper has appeared in Publications math\'ematiques de l'IH\'ES. The final publication is available at http://www.springerlink.co