Compressed intramolecular dispersion interactions.

The feasibility of the compression of localized virtual orbitals is explored in the context of intramolecular long-range dispersion interactions. Singular value decomposition (SVD) of coupled cluster doubles amplitudes associated with the dispersion interactions is analyzed for a number of long-chain systems, including saturated and unsaturated hydrocarbons and a silane chain. Further decomposition of the most important amplitudes obtained from these SVDs allows for the analysis of the dispersion-specific virtual orbitals that are naturally localized. Consistent with previous work on intermolecular dispersion interactions in dimers, it is found that three important geminals arise and account for the majority of dispersion interactions at the long range, even in the many body intramolecular case. Furthermore, it is shown that as few as three localized virtual orbitals per occupied orbital can be enough to capture all pairwise long-range dispersion interactions within a molecule

Fully anharmonic infrared cascade spectra of polycyclic aromatic hydrocarbons

The infrared (IR) emission of polycyclic aromatic hydrocarbons (PAHs) permeates our universe; astronomers have detected the IR signatures of PAHs around many interstellar objects. The IR emission of interstellar PAHs differs from their emission as seen under conditions on Earth, as they emit through a collisionless cascade down through their excited vibrational states from high internal energies. The difficulty in reproducing interstellar conditions in the laboratory results in a reliance on theoretical techniques. However, the size and complexity of PAHs requires careful consideration when producing the theoretical spectra. In this work we outline the theoretical methods necessary to lead to a fully theoretical IR cascade spectra of PAHs including: an anharmonic second order vibrational perturbation theory (VPT2) treatment; the inclusion of Fermi resonances through polyads; and the calculation of anharmonic temperature band shifts and broadenings (including resonances) through a Wang--Landau approach. We also suggest a simplified scheme to calculate vibrational emission spectra that retains the essential characteristics of the full IR cascade treatment and can directly transform low temperature absorption spectra in IR cascade spectra. Additionally we show that past astronomical models were in error in assuming a 15 cm$^{-1}$ correction was needed to account for anharmonic emission effects

Differential subcellular recruitment of monoacylglycerol lipase generates spatial specificity of 2-arachidonoyl glycerol signaling during axonal pathfinding

Peer reviewedPublisher PD

Adjuvant interferon alpha 2b in high risk melanoma – the Scottish study

In 1989, the Scottish melanoma group initiated a randomized trial, comparing observation alone with 6 months' therapy with low dose interferon α (given subcutaneously 3 MU day–1, thrice weekly), for patients with primary melanomas of at least 3 mm Breslow thickness, or with evidence of regional node involvement. The trial was closed in 1993 with only 95 eligible patients randomized. There were no toxic deaths, and no patient failed to complete the treatment for reasons of toxicity. 6 months' treatment with low-dose interferon-α resulted in a statistically significant improved disease-free survival for up to 24 months after randomization (P< 0.05). However, at a median follow-up of over 6 years, although there was an apparent improvement in disease-free survival (from 9 to 22 months), and overall survival (from 27 to 39 months), consistent with larger studies powered to detect such differences, these differences were not statistically significant. The data therefore suggest that 6 months of low-dose interferon is active, and confirm the importance of the large randomized studies, such as the UKCCCR AIM-High and EORTC trials, that seek to confirm a possible survival advantage for low or intermediate dose interferon. © 2001 Cancer Research Campaign http://www.bjcancer.co

The RoboCOS Study : Development of an international core outcome set for the comprehensive evaluation of patient, surgeon, organisational and population level impacts of robotic assisted surgery

ACKNOWLEDGEMENTS We would like to thank sincerely all those who contributed to the interviews, the focus group, the Delphi survey and the consensus meeting, and Paul Manson (Health Services Research Unit, University of Aberdeen) for helping to retrieve full text copies of reports identified by the literature search. We also thank HSRU (Health Services Research Unit) at University of Aberdeen for providing support for this work. Funding: The study was funded from NHS Grampian Endowment Fund and the University of Aberdeen. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Copyright: © 2023 Robertson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Peer reviewedPublisher PD

'I've got to get something out of it. And so do they': experiences of people with aphasia and university students participating in a communication partner training programme for healthcare professionals

Communication partner training (CPT) has been used to support communication partners to interact successfully with people with aphasia (PWA). Through successful CPT interaction PWA's accessibility to healthcare is notably improved. The present study sought to build on prior studies by investigating the experiences of individuals with aphasia and healthcare providers to ascertain what they deemed to be beneficial from CPT and what could be refined or improved, dependent on the setting and skill set of those participating.To gain an understanding of the experiences of PWA involved in the provision of CPT to health professional (HP) students. Also to investigate the experiences of HP students who participated in the CPT programme.Eight PWA and 77 HP students who had completed a CPT programme participated in a focus group/semi-structured interview (PWA) and feedback session (HP students) moderated by two speech-language pathologists (SLPs). These sessions were recorded (audio and video), transcribed verbatim, including non-verbal communication, and analyzed using qualitative content analysis.Overall, the study sought to understand experiences of the training. Both the PWA and HP students reported positive experiences of CPT. PWA discussed their perception that CPT improved HPs and HP students' understanding and interactions conversing with them and emphasized the need for training and education for all health related professions. HP students enjoyed the opportunity to experience interacting with PWA, without being 'assessed' and felt it consolidated their learning based on lecture content.Inclusive and accessible healthcare is paramount to ensure the engagement of patients and providers. Based on the experiences and feedback of the participants in this current study, CPT offers a salient and practical training method with potential to improve practice. Participants perceived CPT to be beneficial and validated the need for the training to support PWA accessing healthcare

Methane output of rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus) fed a hay-only diet: Implications for the scaling of methane production with body mass in non-ruminant mammalian herbivores

It is assumed that small herbivores produce negligible amounts of methane, but it is unclear whether this is a physiological peculiarity, or simply a scaling effect. A respiratory chamber experiment was conducted with six rabbits (Oryctolagus cuniculus, 1.57 ± 0.31 kg body mass) and six guinea pigs (Cavia porcellus, 0.79 ± 0.07 kg) offered grass hay ad libitum. Daily dry matter (DM) intake and DM digestibility were 50 ± 6 g kg–0.75 d–1 and 55 ± 6 % in rabbits and 59 ± 11 g kg–0.75 d–1 and 61 ± 3 % in guinea pigs, respectively. Methane production was similar for both species (0.20 ± 0.10 L d–1 and 0.22 ± 0.08 L d–1) and represented 0.69 ± 0.32 and 1.03 ± 0.29 % of gross energy intake in rabbits and guinea pigs, respectively. In relation to body mass (BM) guinea pigs produced significantly more methane. The data on methane per unit of BM obtained in this study and from literature on methane output of elephant, wallabies and hyraxes all lay close to a regression line derived from roughage-fed horses, showing an increase in methane output with BM. The regression including all data was nearly identical to that based on the horse data only (methane production in horses [L d–1] = 0.18 body mass [kg]0.97 (95%CI 0.92–1.02)) and indicates linear scaling. Because feed intake typically scales to BM0.75, linear scaling of methane output translates into increasing energetic losses at increasing BM. Accordingly, the data collection indicates that an increasing proportion of ingested gross energy is lost because relative methane production increases with BM. Different from ruminants, such losses (1-2% of gross energy) appear too small in non-ruminant herbivores to represent a physiologic constraint on body size. Nevertheless, this relationship may represent a physiological disadvantage with increasing herbivore body size