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This paper introduces the design concept of a dual-functional molecular dyad tailored specifically for solution-processable organic light-emitting diodes (OLEDs). Cy-tmCPBN, characterized by an asymmetric molecular dyad structure, integrates a host unit (tmCP) and a multiple-resonance (MR) emitter (CzBN) via a non-conjugated cyclohexane linker. Cy-tmCPBN exhibited efficient intramolecular energy transfers (EnTs) from tmCP to the CzBN unit, as confirmed by time-resolved fluorescence experiments. The fluorescence lifetime of the tmCP unit was approximately three times shorter in a highly diluted solution of Cy-tmCPBN than in a mixed solution of Cy-tmCP and Cy-CzBN. In addition, Cy-tmCPBN exhibited excellent solubility and film-forming ability, making it suitable for solution processing. Notably, OLEDs utilizing Cy-tmCPBN achieved over twice the brightness and improved external quantum efficiency of 12.3% compared to OLEDs using Cy-CzBN with the same concentration of CzBN in the emitting layer. The improved OLED performance can be explained by the increased EnT efficiency from Cy-tmCP to Cy-tmCPBN and the intramolecular EnT within Cy-tmCPBN. In our dual-functional dyad, incorporating both host and emitter units in an asymmetric molecular dyad structure, we induced a positive synergy effect with the host moiety, enhancing OLED performance through intramolecular EnT., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objectives: The COVID-19 is a global health issue with widespread impact around the world, and many countries initiated lockdowns as part of their preventive measures. We aim to quantify the duration of delay in discharge to community from Community Hospitals, as well as quantify adverse patient outcomes post discharge pre and during lockdown period., Design and Methods: We conducted a before-after study comparing the length of stay in Community Hospitals, unscheduled readmissions or Emergency Department attendance, patients' quality of life using EQ5D-5l, number and severity of falls, in patients admitted and discharged before and during lockdown period., Results: The average length of stay in the lockdown group (27.77 days) were significantly longer than that of the pre-lockdown group (23.76 days), p  = 0.003. There were similar proportions of patients with self-reported falls post discharge between both groups. Patients in the pre-lockdown group had slightly better EQ-5D-5l Index score at 0.55, compared to the lockdown study group at 0.49. Half of the patients in both groups were referred to Community Care Services on discharge., Conclusion: Our study would help in developing a future systematic preparedness guideline and contingency plans in times of disease outbreak and other similar public health emergencies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Chia, Xia, Kwan, Lim, Tan, Low, Xu, Loo, Kong, Koh, Towle, Lim, Yoon, Seah and Low.)

Introduction: The COVID-19 pandemic affects the process of care transition for patients with underlying chronic conditions. This study aims to explore the impact of the pandemic measures on discharge planning and continuum of care for vulnerable older patients from multi-stakeholder perspectives., Methods: We conducted focus group discussions and individual interviews with healthcare workers, community partners, government officials and family caregivers in Singapore. All interviews were audio-recorded, transcribed verbatim and thematically analysed., Results: A total of 53 individuals participated in the study. Discharge planning and care continuity in the community were affected primarily by the limited step-down care options and remote assessment of discharge needs. Participants felt a need to revisit the decision of 'essential' community services through engagement of all stakeholders to enhance care community.To improve better care transition, participants suggested the need for clearer communication of guidelines, improved intersectoral collaboration, shared responsibility of patient care through community engagement and employment of novel models of care., Conclusion: The pandemic measures generated challenges of safe discharge of patients and care continuity in the community. Findings shed light on the need to proactively assess care pathways and catalyse novel models to improve care transition beyond the pandemic., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2022 The Author(s).)

Background: The coronavirus disease-19 (COVID-19) pandemic has cost lives and economic hardships globally. Various studies have found a number of different factors, such as hyperinflammation and exhausted/suppressed T cell responses to the etiological SARS coronavirus-2 (SARS-CoV-2), being associated with severe COVID-19. However, sieving the causative from associative factors of respiratory dysfunction has remained rudimentary., Methods: We postulated that the host responses causative of respiratory dysfunction would track most closely with disease progression and resolution and thus be differentiated from other factors that are statistically associated with but not causative of severe COVID-19. To track the temporal dynamics of the host responses involved, we examined the changes in gene expression in whole blood of 6 severe and 4 non-severe COVID-19 patients across 15 different timepoints spanning the nadir of respiratory function., Findings: We found that neutrophil activation but not type I interferon signaling transcripts tracked most closely with disease progression and resolution. Moreover, transcripts encoding for protein phosphorylation, particularly the serine-threonine kinases, many of which have known T cell proliferation and activation functions, were increased after and may thus contribute to the upswing of respiratory function. Notably, these associative genes were targeted by dexamethasone, but not methylprednisolone, which is consistent with efficacy outcomes in clinical trials., Interpretation: Our findings suggest neutrophil activation as a critical factor of respiratory dysfunction in COVID-19. Drugs that target this pathway could be potentially repurposed for the treatment of severe COVID-19., Funding: This study was sponsored in part by a generous gift from The Hour Glass. EEO and JGL are funded by the National Medical Research Council of Singapore, through the Clinician Scientist Awards awarded by the National Research Foundation of Singapore., Competing Interests: Declaration of Competing Interests Dr Eng Eong Ooi reports grants from National Medical Research Council, Singapore, during the conduct of the study; personal fees from Tychan Private Limited, outside the submitted work; the other authors declare no competing interests., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Photostability of small-molecule (SM)-based organic photovoltaics (SM-OPVs) is greatly improved by utilizing a ternary photo-active layer incorporating a small amount of a conjugated polymer (CP). Semi-crystalline poly[(2,5-bis(2-hexyldecyloxy)phenylene)- alt -(5,6-difluoro-4,7-di(thiophen-2-yl)benzo[ c ][1,2,5]thiadiazole)] (PPDT2FBT) and amorphous poly[(2,5-bis(2-decyltetradecyloxy)phenylene)- alt -(5,6-dicyano-4,7-di(thiophen-2-yl)benzo[ c ][1,2,5]thiadiazole)] (PPDT2CNBT) with similar chemical structures were used for preparing SM:fullerene:CP ternary photo-active layers. The power conversion efficiency (PCE) of the ternary device with PPDT2FBT (Ternary-F) was higher than those of the ternary device with PPDT2CNBT (Ternary-CN) and a binary SM-OPV device (Binary) by 15% and 17%, respectively. The photostability of the SM-OPV was considerably improved by the addition of the crystalline CP, PPDT2FBT. Ternary-F retained 76% of its initial PCE after 1500 h of light soaking, whereas Ternary-CN and Binary retained only 38% and 17% of their initial PCEs, respectively. The electrical and morphological analyses of the SM-OPV devices revealed that the addition of the semi-crystalline CP led to the formation of percolation pathways for charge transport without disturbing the optimized bulk heterojunction morphology. The CP also suppressed trap-assisted recombination and enhanced the hole mobility in Ternary-F. The percolation pathways enabled the hole mobility of Ternary-F to remain constant during the light-soaking test. The photostability of Ternary-CN did not improve because the addition of the amorphous CP inhibited the formation of ordered SM domains.

Subwavelength gratings have been of great interest recently due to their ability to eliminate multiple orders. However, high index contrast ( Δ n ∼ 3 ) is typically achieved using metals or high-index dielectrics surrounded by vacuum in order to maintain good optical selectivity. Here, we theoretically propose and experimentally realize a selective subwavelength grating using an index contrast of Δ n ∼ 1.2 without vacuum. Despite its low index contrast, our simulation and experiments show that good optical selectivity is achieved using the same physics as subwavelength gratings made of high-index contrast. Such polymer-based encapsulated gratings are easier to scale up for use in large-area applications such as photovoltaics and lighting.

Highly efficient nonfullerene polymer solar cells (PSCs) are developed based on two new phthalimide-based polymers phthalimide-difluorobenzothiadiazole (PhI-ffBT) and fluorinated phthalimide-ffBT (ffPhI-ffBT). Compared to all high-performance polymers reported, which are exclusively based on benzo[1,2- b :4,5- b ']dithiophene (BDT), both PhI-ffBT and ffPhI-ffBT are BDT-free and feature a D-A 1 -D-A 2 type backbone. Incorporating a second acceptor unit difluorobenzothiadiazole leads to polymers with low-lying highest occupied molecular orbital levels (≈-5.6 eV) and a complementary absorption with the narrow bandgap nonfullerene acceptor IT-4F. Moreover, these BDT-free polymers show substantially higher hole mobilities than BDT-based polymers, which are beneficial to charge transport and extraction in solar cells. The PSCs containing difluorinated phthalimide-based polymer ffPhI-ffBT achieve a substantial PCE of 12.74% and a large V oc of 0.94 V, and the PSCs containing phthalimide-based polymer PhI-ffBT show a further increased PCE of 13.31% with a higher J sc of 19.41 mA cm -2 and a larger fill factor of 0.76. The 13.31% PCE is the highest value except the widely studied BDT-based polymers and is also the highest among all benzothiadiazole-based polymers. The results demonstrate that phthalimides are excellent building blocks for enabling donor polymers with the state-of-the-art performance in nonfullerene PSCs and the BDT is not necessary for constructing such donor polymers.

Head-to-head linked bithiophenes with planar backbones hold distinctive advantages for constructing organic semiconductors, such as good solubilizing capability, enabling narrow bandgap, and effective tuning of frontier molecular orbital (FMO) levels using minimal thiophene numbers. In order to realize planar backbone, alkoxy chains are typically installed on thiophene head positions, owing to the small van der Waals radius of oxygen atom and accompanying noncovalent S⋯O interaction. However, the strong electron donating alkoxy chains on the electron-rich thiophenes lead to elevated FMO levels, which are detrimental to material stability and device performance. Thus, a new design approach is needed to counterbalance the strong electron donating property of alkoxy chains to bring down the FMOs. In this study, we designed and synthesized a new head-to-head linked building block, 4-alkoxy-5-(3-alkylthiophen-2-yl)thiazole (TRTzOR), using an electron-deficient thiazole to replace the electron-rich thiophene. Compared to previously reported 3-alkoxy-3'-alkyl-2,2'-bithiophene (TRTOR), TRTzOR is a weaker electron donor, which considerably lowers FMOs and maintains planar backbone through the noncovalent S⋯O interaction. The new TRTzOR was copolymerized with benzothiadiazoles with distinct F numbers to yield a series of polymer semiconductors. Compared to TRTOR-based analogous polymers, these TRTzOR-based polymers have broader absorption up to 950 nm with lower-lying FMOs by 0.2-0.3 eV, and blending these polymers with PC 71 BM leads to polymer solar cells (PSCs) with improved open-circuit voltage ( V oc ) by ca. 0.1 V and a much smaller energy loss ( E loss ) as low as 0.59 eV. These results demonstrate that thiazole substitution is an effective approach to tune FMO levels for realizing higher V oc s in PSCs and the small E loss renders TRTzOR a promising building block for developing high-performance organic semiconductors., Competing Interests: There are no conflicts of interest to declare, (This journal is © The Royal Society of Chemistry.)

p16 is a negative regulator of cell proliferation and is considered a tumor suppressor protein. Alterations in p16 protein expression are associated with tumor development and progression. However, the p16 expression status in the peritumoral stroma has not been investigated in the endometrium. Therefore, we evaluated stromal p16 expression in different types of endometrial lesions using immunohistochemistry. Differences in the p16 expression status according to the degree of malignancy and histological type were analyzed. This study included 62, 26, and 36 cases of benign, precancerous, and malignant endometrial lesions, respectively. Most benign lesions showed negative or weak expression, whereas precancerous lesions showed a variable degree of staining proportion and intensity. Atypical hyperplasia/endometrial intraepithelial neoplasia (AH/EIN) and serous endometrial intraepithelial carcinoma (SEIC) had significantly higher stromal p16 expression levels than benign lesions. Endometrioid carcinoma (EC), serous carcinoma (SC), and carcinosarcoma showed significantly elevated stromal p16 expression levels compared with benign and precancerous lesions. In addition, there were significant differences in stromal p16 expression between AH/EIN and SEIC and between EC and SC. In contrast, differences in stromal p16 expression among nonpathological endometrium, atrophic endometrium, endometrial polyp, and hyperplasia without atypia were not statistically significant. Our observations suggest that stromal p16 expression is involved in the development and progression of endometrial carcinoma, and raise the possibility that p16 overexpression in the peritumoral stroma is associated with aggressive oncogenic behavior of endometrial SC.

Determining the viral etiology of respiratory tract infections (RTI) has been limited for the most part to specific primer PCR-based methods due to their increased sensitivity and specificity compared to other methods, such as tissue culture. However, specific primer approaches have limited the ability to fully understand the diversity of infecting pathogens. A pathogen chip system (PathChip), developed at the Genome Institute of Singapore (GIS), using a random-tagged PCR coupled to a chip with over 170,000 probes, has the potential to recognize all known human viral pathogens. We tested 290 nasal wash specimens from Filipino children <2 years of age with respiratory tract infections using culture and 3 PCR methods-EraGen, Luminex, and the GIS PathChip. The PathChip had good diagnostic accuracy, ranging from 85.9% (95% confidence interval [CI], 81.3 to 89.7%) for rhinovirus/enteroviruses to 98.6% (95% CI, 96.5 to 99.6%) for PIV 2, compared to the other methods and additionally identified a number of viruses not detected by these methods.

In April 2009, a new influenza A (H1N1 2009) virus emerged that rapidly spread around the world. While current variants of this virus have caused widespread disease, particularly in vulnerable groups, there remains the possibility that future variants may cause increased virulence, drug resistance or vaccine escape. Early detection of these virus variants may offer the chance for increased containment and potentially prevention of the virus spread. We have developed and field-tested a resequencing kit that is capable of interrogating all eight segments of the 2009 influenza A(H1N1) virus genome and its variants, with added focus on critical regions such as drug-binding sites, structural components and mutation hotspots. The accompanying base-calling software (EvolSTAR) introduces novel methods that utilize neighbourhood hybridization intensity profiles and substitution bias of probes on the microarray for mutation confirmation and recovery of ambiguous base queries. Our results demonstrate that EvolSTAR is highly accurate and has a much improved call rate. The high throughput and short turn-around time from sample to sequence and analysis results (30 h for 24 samples) makes this kit an efficient large-scale evolutionary biosurveillance tool.