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In the realm of flexible optoelectronic devices, intrinsic flexible fully π‐conjugated polymers (FπCPs) assume a pivotal role owing to their concurrent intrinsic viscoelasticity and robust optoelectronic properties. As flexible devices are destined to encounter diverse stress environments, the selection of functional materials based on mechanical requirements becomes imperative. Here, VPERD assessment system is introduced to scrutinize the mechanical properties of side‐chain plasticizing FπCPs. The acronym VPERD encapsulates five key aspects of mechanical characteristics, namely viscidity (V), plasticity (P), elasticity (E), rigidity (R), and ductility (D). The mechanical characteristics of FπCPs are tuned through the control of flexible chain density (FCD). Enhancing FCD induces superior chain softness, favorable solubility, and heightened viscoplasticity. Through precise regulation of FCD and thoughtful structural design, freestanding FπCPs nano‐films exhibit a remarkable maximum fracture strain of ≈50%. Deep‐blue flexible polymer light‐emitting diodes (PLEDs) reveal that maintaining FCD at ≈50% achieves a balance between mechanical and optoelectronic properties. The stretched films after strain fatigue both show that mild strain is conducive to enhancing the efficiency of FπCPs films and devices. According to VPERD assessment system, the prerequisite for achieving intrinsically flexible FπCPs lies in controlling the degree of side‐chain internal plasticization through the tuning of FCD. [ABSTRACT FROM AUTHOR]

Conjugated polymers with p‐orbital overlap show intramolecular‐conformation‐dependent photophysical and electrical properties. Compared to the non‐planar segments, the planar conformation segments have a relatively long effective conjugated length and rigid backbone structure, which are beneficial for the enhancement of optoelectronic properties. Herein, the effect of film thickness on the formation capacity of planar (β) conformations in polyfluorene (poly[4‐(octyloxy)‐9,9‐diphenylfluorene‐2,7‐diyl]‐co‐[5‐(octyloxy)‐9,9‐diphenylfluorene‐2,7‐diyl], PODPF) for the fabrication of stable deep‐blue polymer light‐emitting diodes (PLEDs) is explored. Thickness‐tunable films with thicknesses ranging from 15 to 270 nm by controlling the concentration of precursor solution are prepared. The main observations are as follows. The PODPF chains in thin films are less likely to adopt the β conformations associated with the loose interchain packing in nano‐aggregates than those in thick films. Red‐shifted and well‐resolved emission spectra are observed for the annealed film with a high thickness, indicating the greater presence of β‐conformation segments. More interestingly, interchain aggregation is a necessary but not sufficient condition for the formation of β conformations. Finally, PLEDs based on β‐conformation segments have outstanding brightness, low turn‐on voltage, and stable deep‐blue electroluminescent behavior, confirming the unique advantage of planar conformation for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Green‐processable printed large‐area light‐emitting diode (LED) is the crucial component of the high quality solid lighting and flat‐panel display. Accelerating the replacement from fossil‐based solvents to sustainable ecofriendly solvent is desirable for solution‐based printed organic electronics. Herein, by simple introducing methyl to the benzene groups of polydiarylfluorene‐based polymer, this work realizes the solution processing of blue polymer light‐emitting diodes (PLEDs) with a bio‐based solvent of limonene toward large‐area printed display. Film processed from this solvent exhibits satisfactory morphology and remarkable photophysical performances, even though the polymer chains show more serious aggregation in solution. What's more, devices fabricated with spin‐coated films present higher external quantum efficiency (EQE) and better spectra repeatability. Encouraged by the good film‐forming ability of this polymer in limonene, this work realizes the fabrication of printed large‐area films (5 × 5 cm2) with uniform emission and surface morphology by blade coating. Furthermore, this work develops passive matrix (PM) PLEDs arrays with 20 × 20 pixels that can dynamically display monochrome letters and numbers, demonstrating the potential application of cost‐effective printing techniques in large‐area display. [ABSTRACT FROM AUTHOR]

Large‐area polymer light‐emitting diodes (PLEDs) manufactured by printing are required for flat‐panel lighting and displays. Nevertheless, it remains challenging to fabricate large‐area and stable deep‐blue PLEDs with narrowband emission due to the difficulties in precisely tuning film uniformity and obtaining single‐exciton emission. Herein, efficient and stable large‐area deep‐blue PLEDs with narrowband emission are prepared from encapsulated polydiarylfluorene. Encapsulated polydiarylfluorenes presented an efficient and stable deep‐blue emission (peak: 439 nm; full width at half maximum (FWHM): 39 nm) in the solid state due to their single‐chain emission behavior without inter‐backbone chain aggregation. Large‐area uniform blade‐coated films (16 cm2) are also fabricated with excellent smoothness and morphology. Benefitting from efficient emission and excellent printed capacity, the blade‐coated PLEDs with a device area of 9 mm2 realized uniform deep‐blue emission (FWHM: 38 nm; CIE: 0.153, 0.067), with a corresponding maximum external quantum efficiency and the brightness comparable to those of devices based on spin‐coated films. Finally, considering the essential role of deep‐blue LEDs, a preliminary patterned PLED array with a pixel size of 800 × 1000 µm2 and a monochrome display is fabricated, highlighting potential full‐color display applications. [ABSTRACT FROM AUTHOR]

Control of the secondary conformational behavior of light‐emitting conjugated polymers (LCPs) is essential to obtain deep‐blue emission with a narrowband and stable color purity. Naturally π–π interactions induced by the planar aromatic segments may be easily observed in liner‐type LCPs, which lead to reduced emission efficiency, color purity, and energy bandgap. Herein, an alternating copolymerization strategy is proposed to obtain the singlet exciton behavior of a planar conformational segment from polydiarylfluorenes‐copolymers (P7‐6DPF, P7‐8DPF, and P7‐9DPF) toward deep‐blue polymer light‐emitting diodes (PLEDs). Compared to the highly crystalline capacity of P7DPF, P7‐8DPF, and P8DPF, alternative P7‐6DPF and P7‐9DPF present a feature and well‐resolved emission from a planar conformational segment of polyfluorene without obvious polaron features and charge transfer states. More interestingly, P7‐6DPF and P7‐9DPF show thickness‐independent electroluminescence (EL) behavior with a stable deep‐blue color purity, which is the precondition to fabricate large‐scale and high‐quality PLEDs. Finally, compared to control devices, PLEDs based on the P7‐6DPF and P7‐9DPF planar (β) conformational films present a well‐resolved and narrowband emission, stable EL spectra, high brightness (two‐ to threefold), and high current efficiency (1.3‐fold). Therefore, optimizing hierarchical structure via alternating copolymerization is an effective strategy to improve the performance and stability of deep‐blue PLEDs. [ABSTRACT FROM AUTHOR]

The outbreak of coronavirus disease 2019 (COVID‐19) has globally strained medical resources and caused significant mortality. This study was aimed to develop and validate a prediction model based on clinical features to estimate the risk of patients with COVID‐19 at admission progressing to critical patients. Patients admitted to the hospital between January 16, 2020, and March 10, 2020, were retrospectively enrolled, and they were observed for at least 14 days after admission to determine whether they developed into severe pneumonia. According to the clinical symptoms, all patients were divided into four groups: mild, normal, severe, and critical. A total of 390 patients with COVID‐19 pneumonia were identified, including 212 severe patients and 178 nonsevere patients. The least absolute shrinkage and selection operator (LASSO) regression reduced the variables in the model to 6, which are age, number of comorbidities, computed tomography severity score, lymphocyte count, aspartate aminotransferase, and albumin. The area under curve of the model in the training set is 0.898, and the specificity and sensitivity were 89.7% and 75.5%. The prediction model, nomogram might be useful to access the onset of severe and critical illness among COVID‐19 patients at admission, which is instructive for clinical diagnosis. [ABSTRACT FROM AUTHOR]

This study aims to explore the clinical effect of Arbidol (ARB) combined with adjuvant therapy on patients with coronavirus disease 2019 (COVID‐19). The study included 62 patients with COVID‐19 admitted to the First Hospital of Jiaxing from January to March 2020, and all patients were divided into the test group and the control group according to whether they received ARB during hospitalization. Various indexes in the two groups before and after treatment were observed and recorded, including fever, cough, hypodynamia, nasal obstruction, nasal discharge, diarrhea, C‐reactive protein (CRP), procalcitonin (PCT), blood routine indexes, blood biochemical indexes, time to achieve negative virus nucleic acid, and so on. The fever and cough in the test group were relieved markedly faster than those in the control group (P <.05); there was no obvious difference between the two groups concerning the percentage of patients with abnormal CRP, PCT, blood routine indexes, aspartate aminotransferase, and alanine aminotransferase (P >.05); the time for two consecutive negative nucleic acid tests in the test group were shorter than that in the control group; the hospitalization period of the patients in the test group and control group were (16.5 ± 7.14) days and (18.55 ± 7.52) days, respectively. ARB combined with adjuvant therapy might be able to relieve the fever of COVID‐19 sufferers faster and accelerate the cure time to some degree, hence it's recommended for further research clinically. Research Highlights: 1.Arbidol combined with adjuvant therapy could shorten the course of patient's basic symptoms;2.Arbidol combined with adjuvant therapy could normalize patient's temperature faster;3.Viral nucleic acid of patients treated with Arbidol combined with adjuvant therapy could turn negative within a shorter time. [ABSTRACT FROM AUTHOR]

In regression problems where there is no known true underlying model, conformal prediction methods enable prediction intervals to be constructed without any assumptions on the distribution of the underlying data, except that the training and test data are assumed to be exchangeable. However, these methods bear a heavy computational cost—and, to be carried out exactly, the regression algorithm would need to be fitted infinitely many times. In practice, the conformal prediction method is run by simply considering only a finite grid of finely spaced values for the response variable. This paper develops discretized conformal prediction algorithms that are guaranteed to cover the target value with the desired probability and that offer a trade‐off between computational cost and prediction accuracy. Copyright © 2018 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

As a Gram-negative anaerobic bacterium, Akkermansia muciniphila (AKK) participates in the immune response in many cancers. Our study focused on the factors and molecular mechanisms of AKK affecting immune escape in lung adenocarcinoma (LUAD). We cultured AKK bacteria, prepared AKK outer membrane protein Amuc&#95;1100 and constructed a subcutaneous graft tumour mouse model. A549, NCI-H1395 cells and mice were respectively treated with inactivated AKK, Amuc&#95;1100, Ruxolitinib (JAK inhibitor) and RO8191 (JAK activator). CD8 + T cells that penetrated the membrane were counted in the Transwell assay. The toxicity of CD8 + T cells was evaluated by lactate dehydrogenase assay. Western blot was applied to determine JAK/STAT-related protein and PD-L1 expression, whilst CCL5, granzyme B and INF-γ expression were assessed through enzyme-linked immunosorbent assay (ELISA). The proportion of tumour-infiltrating CD8 + T cells and the levels of granzyme B and INF-γ were determined by flow cytometry. AKK markedly accelerated A549 and NCI-H1395 recruiting CD8 + T cells and enhanced CD8 + T cell toxicity. Amuc&#95;1100 purified from AKK exerted the same promoting effects. Besides, Amuc&#95;1100 dramatically suppressed PD-L1, p-STAT and p-JAK expression and enhanced CCL5, granzyme B and INF-γ expression. Treatment with Ruxolitinib accelerated A549 and NCI-H1395 cells recruiting CD8 + T cells, enhanced CD8 + T cell toxicity, CCL5, granzyme B and INF-γ expression, and inhibited PD-L1 expression. In contrast, the RO8191 treatment slowed down the changes induced by Amuc&#95;1100. Animal experiments showed that Amuc&#95;1100 was found to increase the number of tumour-infiltrating CD8 + T cells, increase the levels of granzyme B and INF-γ and significantly inhibit the expression of PD-L1, p-STAT and p-JAK, which exerted an antitumour effect in vivo. In conclusion, through inhibiting the JAK/STAT signalling pathway, AKK outer membrane protein facilitated the recruitment of CD8 + T cells in LUAD and suppressed the immune escape of cells., (© 2024 The Author(s). Microbial Biotechnology published by John Wiley & Sons Ltd.)