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Coupling together the ferroelectric, pyroelectric, and photovoltaic characteristics within a single material is a novel way to improve the performance of photodetectors. In this work, we take advantage of the triple multifunctionality shown by 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BCZT), as demonstrated in an Al/Si/SiOx/BCZT/ITO thin-film device. The Si/SiOx acts as an n-type layer to form a metal–ferroelectric–insulator–semiconductor heterostructure with the BCZT, and with Al and ITO as electrodes. The photo-response of the device, with excitation from a violet laser (405 nm wavelength), is carefully investigated, and it is shown that the photodetector performance is invariant with the chopper frequency owing to the pyro-phototronic effect, which corresponds to the coupling together of the pyroelectric and photovoltaic responses. However, the photodetector performance was significantly better than that of the devices operating based only on the pyro-phototronic effect by a factor of 4, due to the presence of ferroelectricity in the system. Thus, after a poling voltage of −15 V, for a laser power density of 230 mW/cm2 and at a chopper frequency of 400 Hz, optimized responsivity, detectivity, and sensitivity values of 13.1 mA/W, 1.7 × 1010 Jones, and 26.9, respectively, are achieved. Furthermore, ultrafast rise and fall times of 2.4 and 1.5 µs, respectively, are obtained, which are 35,000 and 36,000 times faster rise and fall responses, respectively, than previous reports of devices with the ferro–pyro–phototronic effect. This is understood based on the much faster ferroelectric switching in ferroelectric thin films owing to the predominant 180° domains in a single direction out of plane., This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding Contracts UIDB/04650/2020. This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 958174 (M-ERA-NET3/0003/2021—NanOx4EStor). The authors would also like to thank engineer José Santos for technical support at the Thin Film Laboratory. J. L. M.-D. and R. L. Z. H. are grateful for EPSRC CAM-IES grant EP/P007767/. R. L. Z. H. also acknowledges support from the Royal Academy of Engineering under the Research Fellowships scheme (No.: RF\201718\1701). J. L. M.-D. acknowledges support from the Royal Academy of Engineering Chair in Emerging Technologies scheme (No.: CIET1819_24) and the ERC grant EROS, EU-H2020-ERC-ADG # 882929.

Missing not at random (MNAR) data poses key challenges for statistical inference because the model of interest is typically not identifiable without imposing further (e.g., distributional) assumptions. Sample selection models have been routinely used for handling MNAR by jointly modelling the outcome and selection variables assuming that these follow a bivariate normal distribution. Recent studies have advocated parametric selection model approaches, for example estimated by multiple imputation and maximum likelihood, that are more robust to departures from the normality assumption. However, the proposed methods have been mostly restricted to a specific joint distribution (e.g., bivariate t-distribution). This paper discusses a flexible copula-based selection approach (which accommodates a wide range of non-Gaussian outcome distributions and offers great flexibility in the choice of functional form specifications for both the outcome and selection equations) and proposes a flexible imputation procedure that generates plausible imputed values from the copula selection model. A simulation study characterises the relative performance of the copula model compared with the most commonly used selection models for estimating average treatment effects with MNAR data. We illustrate the methods in the REFLUX study, which evaluates the causal effect of laparoscopic surgery compared to usual medical management on long-term quality of life in patients with reflux disease. We provide software code for implementing the proposed copula framework using the R package GJRM.

ObjectiveRecent research indicates considerable heterogeneity in the provision of memory assessment services (MAS). However, little is known on the extent of variation in the costs of the services MAS provide. We investigated the costs of supporting patients with suspected dementia, including assessment and support over the following six months. MethodsClinic costs were estimated on the basis of an organisational survey reporting staff roll, grade and activities. Costs of primary health and social care were estimated from questionnaire data reported by carers of patients at baseline, three and six months after referral.ResultsMean monthly staff costs at MAS were £73,000. Imaging at assessment cost an additional £3,500 per month. Monthly clinic cost per new patient assessed varied from £320 to £5,400 across clinics. Additional primary health and social care costs of £130-220 a month between baseline and six months were reported by carers. Costs of pharmacological and non-pharmacological treatments reported by carers were small. Informal care costs dwarfed health and social care costs when valued at a modest unit cost. The overall mean cost of supporting a patient for six months varied from £1,600 to £2,500 dependent on assumptions regarding the proportion of MAS intervention and review costs accrued at six months. ConclusionsThere is considerable variation in the intensity and associated costs of services provided by MAS. Further research should ascertain to what extent such variation is associated with differences in patient outcomes.

The present study evaluates the relationships of pulmonary volumes and flows and the anthropometric variables of standing height, sitting height, and arm span in 100 6-10-year-old children. To be included in the study, all children were required to be healthy and above the 3rd percentile of the curve of Tanner et al. (Arch Dis Child 1966;41:454-471; Arch Dis Child 1966;41:613-635) for height and weight. Standing height, sitting height, and arm span were measured according to standard protocol. The pulmonary function measurements were: tidal volume, minute respiratory volume, respiratory rate, expiratory reserve volume, inspiratory capacity, vital capacity, residual volume (RV), functional residual capacity, total lung capacity (TLC), forced vital capacity (FVC), forced expiratory volume in 1 sec of FVC (FEV(1)), forced expiratory flow measured between 25-75% of FVC, and FEV(1)/FVC and RV/TLC ratios. Simple linear regression best expressed the correlation between pulmonary function and the anthropometric variables. Significant correlations between anthropometric and pulmonary function measurements were observed, with FVC and FEV(1) showing the highest and RV the lowest r(2) values. There was a significant positive correlation between standing height and arm span according to linear regression and Bland-Altman comparison (Bland and Altman, Lancet 1968;8:307-310). Our results suggest that when an accurate determination of standing height cannot be obtained, arm span could be used interchangeably, using the same regression equation. However, for patients with limb deformities, regression equations of pulmonary function measurements in relation to sitting height may be a better choice for estimating pulmonary function.

Carrageenans are highly sulphated galactans, well-known for their thermogelation properties which have been extensively exploited in food and cosmetics industry but poorly explored in the biomedicine field. In this study we have assessed thein vitroandin vivobiocompatibility of κ-carrageenan hydrogels that have been explored for regenerative medicine and tissue engineering applications. Thein vitrocytotoxicity of the materials using a L929 mouse fibroblast cell line was evaluated, and next the effect of κ-carrageenan hydrogels on the activation of human polymorphonuclear neutrophils cells (hPMNs) by the quantification of reactive oxygen species (ROS) by chemiluminescence. Subsequently it was studied the inflammatory/immune reaction to κ-carrageenan hydrogels upon subcutaneous implantation in rats. Explants were retrieved after 1 and 2 weeks of implantation, for histological and RT-PCR analysis. The cytotoxicity screening revealed that κ-carrageenan hydrogels did not significantly affect L929 metabolic activity. Moreover, hPMNs contact with κ-carrageenan resulted in a reduced and a neglectable signal regarding the detection of superoxide and hydroxyl anions, respectively. The results from thein vivoexperiments indicated that κ-carrageenan induce a low inflammatory response. Overall, the data obtained suggests that κ-carrageenan hydrogels are biocompatible and thus can be further studied for their use in target biomedical applications., Contract grant sponsor: Portuguese Foundation for Science and Technology; contract grant number: SFRH/BD/64070/2009 (PhD grant to E.G.P.)Contract grant sponsor: Project MIT-Portugal Program; contract grant number: MIT/ECE/0047/2009

Primary lung tumors are rare in children, and mucoepidermoid carcinoma (MEC) represents less than 10% of them. Additionally, MEC arising from bronchogenic cysts (BC) is particularly unusual. We describe the clinical and genetic findings on a MEC occurring within a previous location of a BC in an adolescent. This particular association has not been previously reported. The lesion revealed normal karyotype without the typical t(11;19)(q21;p13) translocation. Cyclin D1 overexpression (165-fold increase) was demonstrated by real-time PCR although FISH assessment showed normal hybridization at 11q13. Information on these unusual clinical presentations may present relevant insight on tumorigenesis of infrequent pediatric pulmonary tumors.

In this work, we report on the electrical characterization of Ge nanoparticles (NPs) produced by pulsed laser deposition (PLD) at room temperature (RT) in Ar gas inert atmosphere using a shadowed off-axis deposition geometry. Our results show that functional thin films of crystalline Ge NPs embedded between thin alumina films can be obtained on p-type Si(100) substrates following a low temperature and short rapid thermal annealing (RTA) treatment. Metal–oxide–semiconductor (MOS) structures with and without Ge NPs embedded in the alumina were prepared for the electrical measurements. The results indicate a strong memory effect at relatively low programming voltages (±4 V) due to the presence of Ge NPs., Fundação para a Ciência e a Tecnologia (FCT) - PTDC/FIS/70194/2006, SFRH/BPD/64850/2009 (FCT grant), COMPETE, COST MP0901-NanoTP Action, Cooperation program (FCT-CNRST)-2010/2012, Ref. 441.00

Submitted by Armando Silvestre (armsil@ua.pt) on 2012-01-07T17:59:10Z No. of bitstreams: 1 J. Polym. Sci. A Chem., 2011, 49, 3759–3768.PDF: 196203 bytes, checksum: 1b502ccdd35f5bc35f1b775a88c93076 (MD5) Made available in DSpace on 2012-01-27T13:36:09Z (GMT). No. of bitstreams: 1 J. Polym. Sci. A Chem., 2011, 49, 3759–3768.PDF: 196203 bytes, checksum: 1b502ccdd35f5bc35f1b775a88c93076 (MD5) Previous issue date: 2011 FCT - 101058/2008/PTDC/QUI-QUI/