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The investigation of size confinement and chain orientation within the microstructure of a polymer thin film is very important for electronic device applications and fundamental research. Here, we present single step methodology for the synthesis of solution-processable poly (3-hexylthiophene) (P3HT) nanofibers via a self-assembly process. The formation of P3HT nanofibers is confirmed by atomic force microscopy. The synthesized nanofibers are characterized by UV-visible absorption, photoluminescence, and Raman spectroscopy. The aggregation type of self-assembled P3HT is studied by both UV-visible absorbance and photoluminescence spectroscopy. The exciton bandwidth in polymer films is calculated by following the Spano's H-aggregate model and found to be 28 meV. Raman spectroscopy is used to identify the various stretching modes present in nanofibers. The structural investigation using grazing angle X-ray diffraction of nanofibers reveals the presence of alkyl chain ordering. We have fabricated organic Schottky diodes with P3HT nanofibers on indium tin oxide (ITO) coated glass with configuration Al/P3HT/ITO, and current density-voltage characteristics are subsequently used for extracting the electronic parameters of the device. We have also discussed the charge transport mechanism at the metal/polymer interface. [ABSTRACT FROM AUTHOR]

The new frontiers of sustainable cities should focus on urban planning tools and strategies that are able to integrate ecosystem services in urban development. An important step could include the design of nature-based solutions (NbSs) for introducing important ecological functions aiding human well-being and mitigating the loss of soil. In this study, we propose a methodology to analyse, in a spatial way, the effect of land use scenarios generated by urban planning in the provision of ecosystem services. The methodology analyses the variation of ecosystem services, considering the ecosystem services of the study area and their potential roles in changing the functions of planned urban actions as the starting point. One scenario of analysis includes the integration of NbSs into urban planning. The case study is that of a peri-urban area, characterized by an agroecosystem, which is intended for urban development in the municipality of Gallipoli, Southern Italy. The analysis highlights a low provision of ecosystem services by the agroecosystem, which has had the effect of important olive trees being destroyed by Xylella fastidiosa bacteria. Thus, the integration of NbSs and reducing the construction of buildings in the urban neighbourhood plan could improve the quantity of ecosystem services in the area. Moreover, the ecological design of ecosystem services could improve the typology of ecosystem services provision in the area in consideration of the starting points. Therefore, the analysis of the capacity to integrate ecosystem services in urban planning at the neighbourhood scale could be a tool of ecological urban design, useful to support the decision-making processes. [ABSTRACT FROM AUTHOR]

Objective To study the uptake of annual diabetic retinopathy screening and study the 5-year trends in the detection of screen-positive diabetic retinopathy and non-diabetes- related eye disease in a cohort of annually screened individuals. Design Retrospective retinopathy screening attendance and retinopathy grading analysis. Setting Community-based retinopathy screening centres for the Diabetic RetinaScreen Programme. Participants 171 557 were identified by the screening programme to be eligible for annual diabetic retinopathy screening. 120 048 individuals over the age of 12 consented to and attended at least one screening appointment between February 2013 to December 2018. Main Outcome Measures Detection rate per 100 000 of any retinopathy, screen-positive referrable retinopathy and nondiabetic eye disease. Results Uptake of screening had reached 67.2% in the fifth round of screening. Detection rate of screen-positive retinopathy reduced from 13 229 to 4237 per 100 000 screened over five rounds. Detection of proliferative disease had reduced from 2898 to 713 per 100 000 screened. Non-diabetic eye disease detection and referral to treatment centres increased almost eightfold from 393 in round 1 to 3225 per 100 000 screened. The majority of individuals referred to treatment centres for ophthalmologist assessment are over the age of 50 years. Conclusions Screening programme has seen a reduced detection rate both screen-positive retinopathy referral in Ireland over five rounds of screening. Management of nondiabetic eye diseases poses a significant challenge in improving visual outcomes of people living with diabetes in Ireland. [ABSTRACT FROM AUTHOR]

Self-powered photodetectors have grown as inevitable members of the optoelectronic device family. However, it is still challenging to achieve self-powered photodetection with good responsivity in the visible spectrum region. Herein, we report solution-processable poly(3-hexylthiophene) (P3HT)-molybdenum disulfide (MoS2) organic–inorganic hybrid material, which can be used as the active layer in self-powered photodetectors. The morphological and structural properties of the synthesized P3HT-MoS2 hybrid material has been discussed using atomic force microscopy and transmission electron microscopy, respectively. The hybrid material loaded with 1 wt% MoS2 has shown an enhancement in the self-assembly of polymer in the form of fibrillar formation and excellent structural features in terms of π-conjugation. The self-powered photodetectors have been fabricated in indium tin oxide (ITO) coated glass/P3HT-MoS2/Al configuration. The merit of P3HT-MoS2 hybrid photodetectors is measured under the illumination of 470, 530, and 627 nm light in ambient conditions. P3HT-MoS2 photodetectors show significantly higher responsivity and detectivity. The photo responsivity and detectivity in P3HT-MoS2 devices are found to be 271.2 mA W−1 and 4.4 × 1010 jones at zero bias, respectively, for 470 nm light with the optical power density of 74.1 μW cm−2. Furthermore, the photocurrent switching behaviour at periodic illuminations of 1 Hz has also been examined for P3HT-MoS2 self-powered photodetectors. [ABSTRACT FROM AUTHOR]

Introduction: Inherited retinal degenerations (IRD) are rare genetic disorders with > 300 known genetic loci, manifesting variably progressive visual dysfunction. IRDs were historically underserved due to lack of effective interventions. Many novel therapies will require accurate diagnosis (phenotype and genotype), thus an efficient and effective pathway for assessment and management is required.Methods: Using surveys of existing practice patterns and advice from international experts, an all-Ireland IRD service (Target 5000) was designed. Detailed phenotyping was followed by next generation genetic sequencing in both a research and accredited laboratory. Unresolved pedigrees underwent further studies (whole gene/whole exome/whole genome sequencing). Novel variants were interrogated for pathogenicity (cascade screening, in silico analysis, functional studies). A multidisciplinary team (MDT; ophthalmologists, physicians, geneticists, genetic counsellors) reconciled phenotype with genotype. A bespoke care plan was created for each patient comprising supports, existing interventions, and novel therapies/clinical trials.Results and Discussion: Prior to Target 5000, a significant cohort of patients were not engaged with healthcare/support services due to lack of effective interventions. Pathogenic or likely pathogenic variants in IRD-associated genes were detected in 62.3%, with 11.6% having variants of unknown significance. The genotyping arm of Target 5000 allowed a 42.73% cost saving over independent testing, plus the value of MDT expertise/processing. Partial funding has transferred from charitable sources to government resources.Conclusion: Target 5000 demonstrates efficacious and efficient clinical/genetic diagnosis, while discovering novel IRD-implicated genes/variants and investigating mechanisms of disease and avenues of intervention. This model could be used to develop similar IRD programmes in small/medium-sized nations. [ABSTRACT FROM AUTHOR]

Aims: We aimed to determine the patient and screening-level factors that are associated with non-attendance in the Irish National Diabetic Retinal screening programme (Diabetic RetinaScreen). To accomplish this, we modelled a selection of predictors derived from the historical screening records of patients with diabetes. Methods: In this cohort study, appointment data from the national diabetic retinopathy screening programme (RetinaScreen) were extracted and augmented using publicly available meteorological and geospatial data. A total of 653,969 appointments from 158,655 patients were included for analysis. Mixed-effects models (univariable and multivariable) were used to estimate the influence of several variables on non-attendance to screening appointments. Results: All variables considered for analysis were statistically significant. Variables of note, with meaningful effect, were age (OR: 1.23 per decade away from 70; 95% CI: [1.22–1.24]), type 2 diabetes (OR: 1.10; 95% CI: [1.06–1.14]) and socio-economic deprivation (OR: 1.12; 95% CI: [1.09–1.16]). A majority (52%) of missed appointments were from patients who had missed three or more appointments. Conclusions: This study is the first to outline factors that are associated with non-attendance within the Irish national diabetic retinopathy screening service. In particular, when corrected for age and other factors, patients with type 2 diabetes had higher rates of non-attendance. Additionally, this is the first study of any diabetic screening programme to demonstrate that weather may influence attendance. This research provides unique insight to guide the implementation of an optimal and cost-effective intervention strategy to improve attendance. [ABSTRACT FROM AUTHOR]

The performance of π-conjugated polymer based electronic devices is directly governed by the molecular morphology of polymer aggregation, the extent to which a molecule is electronically coupled (self ordered and interacted) to neighboring molecules, and orientation. The well electronic coupled and crystalline/ordered polymer films have the potential to enhance the charge transport properties up to a benchmark. However, there is insufficient knowledge about the direct formation of large area, oriented, crystalline, and smooth films. In this study, we have presented Langmuir Schaefer technique to obtain the large area, oriented, crystalline, and smooth film of Poly (3,3'''- dialkylquarterthiophene) (PQT-12) polymer. The effect of self ordering and orientation of PQT-12 polymer on optical, morphological, and charge transport properties has been investigated. The prepared films have been characterized by UV-vis spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM), selected area diffractions pattern (SAED), and atomic force micros- copy (AFM) techniques. UV-vis spectra, TEM, SAED, and AFM images of monolayer films reveal the formation of well ordered and electronically coupled polymer domains. Layer by layer deposited films reveal the change in the orientation, which is confirmed by Raman spectra. Electronic properties and layer dependent charge transport properties are investigated using sandwiched structure Al/PQT-12/ITO Schottky configuration with perpendicular to the deposited films. It is observed that the charge transport properties and device electronic parameters (ideality factor and turn on voltage) are significantly changing with increasing the number of PQT-12 layers. Our study also demonstrates the charge transport between polymer crystallites and cause of deviation of ideal behavior of organic Schottky diodes. It may be further explored for improving the performance of other organic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The climatic and non-climatic stresses impacted adversely to the functioning and productivity of the forests, resulting in disturbing the existing carbon flow in the atmosphere. Cedrus deodara occurs in pure forest stands throughout the Western Himalayas and has high biomass and soil carbon sequestration potential. The present study aims to provide the contribution of the Cedrus deodara forests under the current stresses for climate mitigation by analysing the three elevation ranges of the Dhanaulti forest division of Garhwal Himalaya, India. The results report that soil organic carbon (SOC) was adversely and bulk density favourably related with elevation. Moreover, SOC as CO2eq also decreased significantly with an increase in soil depths. Biomass carbon for various parts of the plant was also estimated for the three elevations of the Cedrus deodara forests. The trend in total carbon stock (bole, branch, twig, foliage and soil) decreased significantly with an increase in altitude. The carbon stock of Cedrus deodara forests was maximum (545 t ha−1) at upper altitude (2350 m.a.s.l) and minimum (330 t ha−1) at a lower altitude (2050 m.a.s.l). The difference in litter production between the seasons is significant with maximum production in summer followed by rainy and winter seasons. This study provides inputs for greenhouse gas (GHG) estimation for national communication to various platforms. The information on the soil is crucial for understanding about the ecology of the forests assisting prediction of functioning and productivity of forests. [ABSTRACT FROM AUTHOR]

Ordering and alignment of π-conjugated polymer chains are highly desirable for high performance and long life organic electronic devices. We report here self assembly of ordered and aligned solution processible Poly(3,3″′-dialkylquaterthiophene) (PQT-12) polymer at macroscopic level using Floating Film Transfer Method (FTM). PQT-12 polymer film is formed over solution of ethylene glycol and glycerol at different temperatures viz. 22, 26, 33, and 38 °C. PQT-12 films formed by FTM technique are further characterized for optical and morphological properties. UV-vis absorption (for polarize and unpolarize light) and surface topography/phase imaging are carried out by using UV-vis spectrometer and atomic force microscope (AFM), respectively. UV-vis spectra show the polymer chains alignment perpendicular to the film propagation direction and it is well supported by AFM images. The effect of temperature on ordering and alignment of PQT-12 shows 33 °C as an optimum temperature for alignment of polymer chains (a little compromise in ordering). The heating of polymer films at 110 °C for 2 h in ambient causes significant changes in UV-vis absorbance spectra, optical anisotropy, and AFM topography/phase imaging. Our studies provide better understanding of ordering and alignment of PQT-12 chains and also disordering on heating. This work further provides a facile and user-friendly technique for the long range ordered self assembly of PQT-12, which shows enormous potential for various electronic applications. [ABSTRACT FROM AUTHOR]