On (not) deriving the entropy of barocaloric phase transitions from crystallography and neutron spectroscopy

We review well-known signatures of disorder in crystallographic and inelastic neutron scattering data. We show that these can arise from different types of disorder, corresponding to different values of the system entropy. Correlating the entropy of a material with its atomistic structure and dynamics is in general a difficult problem that requires correlating information between multiple experimental techniques including crystallography, spectroscopy, and calorimetry. These comments are illustrated with particular reference to barocalorics, but are relevant to a broad range of calorics and other disordered crystalline materials.Comment: 11 pages, 3 figure

Effectiveness and cost-effectiveness of a universal parenting skills programme in deprived communities : multicentre randomised controlled trial

Objective: To evaluate the effectiveness and cost utility of a universally provided early years parenting programme. Design: Multicentre randomised controlled trial with cost-effectiveness analysis. Setting: Early years centres in four deprived areas of South Wales. Participants: Families with children aged between 2 and 4 years. 286 families were recruited and randomly allocated to the intervention or waiting list control. Intervention: The Family Links Nurturing Programme (FLNP), a 10-week course with weekly 2 h facilitated group sessions. Main outcome measures: Negative and supportive parenting, child and parental well-being and costs assessed before the intervention, following the course (3 months) and at 9 months using standardised measures. Results: There were no significant differences in primary or secondary outcomes between trial arms at 3 or 9 months. With ‘+’ indicating improvement, difference in change in negative parenting score at 9 months was +0.90 (95%CI −1.90 to 3.69); in supportive parenting, +0.17 (95%CI −0.61 to 0.94); and 12 of the 17 secondary outcomes showed a non-significant positive effect in the FLNP arm. Based on changes in parental well-being (SF-12), the cost per quality-adjusted life year (QALY) gained was estimated to be £34 913 (range 21 485–46 578) over 5 years and £18 954 (range 11 664–25 287) over 10 years. Probability of cost per QALY gained below £30 000 was 47% at 5 years and 57% at 10 years. Attendance was low: 34% of intervention families attended no sessions (n=48); only 47% completed the course (n=68). Also, 19% of control families attended a parenting programme before 9-month follow-up. Conclusions: Our trial has not found evidence of clinical or cost utility for the FLNP in a universal setting. However, low levels of exposure and contamination mean that uncertainty remains. Trial registration: The trial is registered with Current Controlled Trials ISRCTN13919732

Dynamics in the ordered and disordered phases of barocaloric adamantane

High-entropy order-disorder phase transitions can be used for efficient and eco-friendly barocaloric solid-state cooling. Here the barocaloric effect is reported in an archetypal plastic crystal, adamantane. Adamantane has a colossal isothermally reversible entropy change of 106 J K-1 kg-1 . Extremely low hysteresis means that this can be accessed at pressure differences less than 200 bar. Configurational entropy can only account for about 40% of the total entropy change; the remainder is due to vibrational effects. Using neutron spectroscopy and supercell lattice dynamics calculations, it is found that this vibrational entropy change is mainly caused by softening in the high-entropy phase of acoustic modes that correspond to molecular rotations. We attribute this behaviour to the contrast between an 'interlocked' state in the low-entropy phase and sphere-like behaviour in the high-entropy phase. Although adamantane is a simple van der Waals solid with near-spherical molecules, this approach can be leveraged for the design of more complex barocaloric molecular crystals. Moreover, this study shows that supercell lattice dynamics calculations can accurately map the effect of orientational disorder on the phonon spectrum, paving the way for studying the vibrational entropy, thermal conductivity, and other thermodynamic effects in more complex materials.Comment: 14 pages, 6 figure

Evaluating the association of TRPA1 gene polymorphisms with pain sensitivity:a protocol for an adaptive recall by genotype study

BACKGROUND: Pain is a complex polygenic trait whose common genetic underpinnings are relatively ill-defined due in part to challenges in measuring pain as a phenotype. Pain sensitivity can be quantified, but this is difficult to perform at the scale required for genome wide association studies (GWAS). Existing GWAS of pain have identified surprisingly few loci involved in nociceptor function which contrasts strongly with rare monogenic pain states. This suggests a lack of resolution with current techniques. We propose an adaptive methodology within a recall-by-genotype (RbG) framework using detailed phenotyping to screen minor alleles in a candidate ‘nociceptor’ gene in an attempt to estimate their genetic contribution to pain. METHODS/DESIGN: Participants of the Avon Longitudinal Study of Parents and Children will be recalled on the basis of genotype at five common non-synonomous SNPs in the ‘nociceptor’ gene transient receptor potential ankylin 1 (TRPA1). Those homozygous for the common alleles at each of the five SNPs will represent a control group. Individuals homozygous for the minor alleles will then be recruited in a series of three sequential test groups. The outcome of a pre-planned early assessment (interim) of the current test group will determine whether to continue recruitment or switch to the next test group. Pain sensitivity will be assessed using quantitative sensory testing (QST) before and after topical application of 10% cinnamaldehyde (a TRPA1 agonist). DISCUSSION: The design of this adaptive RbG study offers efficiency in the assessment of associations between genetic variation at TRPA1 and detailed pain phenotypes. The possibility to change the test group in response to preliminary data increases the likelihood to observe smaller effect sizes relative to a conventional multi-armed design, as well as reducing futile testing of participants where an effect is unlikely to be observed. This specific adaptive RbG design aims to uncover the influence of common TRPA1 variants on pain sensation but can be applied to any hypothesis-led genotype study where costly and time intensive investigation is required and / or where there is large uncertainty around the expected effect size. Trial registration: ISRCTN, ISRCTN16294731. Retrospectively registered 25th November 2021. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12920-022-01156-5

Difference in Postoperative Outcomes and Perioperative Resource Utilization Between General Surgeons and Pediatric Surgeons: A Systematic Review

Background: Both general surgeons (GS) and pediatric surgeons (PS) perform a high volume of appendectomies in pediatric patients, but there is a paucity of data on these outcomes based on surgeon training. We performed a systematic review and meta-analysis to compare postoperative outcomes and perioperative resource utilization for pediatric appendectomies.Methods: We searched PubMed to identify articles examining the association between surgeon specialization and outcomes for pediatric patients undergoing appendectomies. Study selection, data extraction, risk of bias assessment, and quality assessment were performed by one reviewer, with another reviewer to resolve discrepancies.Results: We identified 4799 articles, with 98.4% (4724/2799) concordance after initial review. Following resolution of discrepancies, 16 studies met inclusion criteria. Of the studies that reported each outcome, GS and PS demonstrated similar rates of readmission within 30 days (pooled RR 1.61 95% CI 0.66, 2.55) wound infections (pooled RR 1.07, 95% CI .55, 1.60), use of laparoscopic surgery (pooled RR 1.87, 95% CI .21, 3.53), postoperative complications (pooled RR 1.40, 95% CI .83, 1.97), use of preoperative imaging (pooled RR .98,95% CI .90, 1.05), and intra-abdominal abscesses (pooled RR .80, 95% CI .03, 1.58). Patients treated by GS did have a significantly higher risk of negative appendectomies (pooled RR 1.47, 95% CI 1.10, 1.84) when compared to PS.Discussion: This is the first meta-analysis to compare outcomes for pediatric appendectomies performed by GS compared to PS. Patient outcomes and resource utilization were similar among PS and GS, except for negative appendectomies were significantly more likely with GS

Effects of the reaction cavity on metastable optical excitation in ruthenium-sulfur dioxide complexes

We report photoexcited-state crystal structures for two new members of the [Ru(SO_2)(NH_3)_4X]Y family: 1:X=H2O, Y=(+/-)-camphorsulfonate_2; 2:X=isonicotinamide, Y=tosylate_2. The excited states are metastable at 100 K, with a photoconversion fraction of 11.1(7)% achieved in 1, and 22.1(10)% and 26.9(10)% at the two distinct sites in 2.We further show using solid-state density-functional-theory calculations that the excited-state geometries achieved are strongly influenced by the local crystal environment. This result is relevant to attempts to rationally design related photoexcitation systems for optical data-storage applications.Comment: 6 pages, 5 figure