Search

Background: This study aims to construct a model predicting the probability of RF in AECOPD patients upon hospital admission. Methods: This study retrospectively extracted data from MIMIC-IV database, ultimately including 3776 AECOPD patients. The patients were randomly divided into a training set (n = 2643) and a validation set (n = 1133) in a 7:3 ratio. First, LASSO regression analysis was used to optimize variable selection by running a tenfold k-cyclic coordinate descent. Subsequently, a multifactorial Cox regression analysis was employed to establish a predictive model. Thirdly, the model was validated using ROC curves, Harrell's C-index, calibration plots, DCA, and K-M curve. Result: Eight predictive indicators were selected, including blood urea nitrogen, prothrombin time, white blood cell count, heart rate, the presence of comorbid interstitial lung disease, heart failure, and the use of antibiotics and bronchodilators. The model constructed with these 8 predictors demonstrated good predictive capabilities, with ROC curve areas under the curve (AUC) of 0.858 (0.836–0.881), 0.773 (0.746–0.799), 0.736 (0.701–0.771) within 3, 7, and 14 days in the training set, respectively and the C-index was 0.743 (0.723–0.763). Additionally, calibration plots indicated strong consistency between predicted and observed values. DCA analysis demonstrated favorable clinical utility. The K-M curve indicated the model's good reliability, revealed a significantly higher RF occurrence probability in the high-risk group than that in the low-risk group (P < 0.0001). Conclusion: The nomogram can provide valuable guidance for clinical practitioners to early predict the probability of RF occurrence in AECOPD patients, take relevant measures, prevent RF, and improve patient outcomes. [ABSTRACT FROM AUTHOR]

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]

The trajectory of the near space hypersonic target interceptor is designed and verified. Firstly, this paper discusses the necessity of the trajectory design of the near space hypersonic target interceptor. Taking the high throw-reentry-glide trajectory scheme of the near space hypersonic as the reference trajectory, the whole trajectory is divided into active phase and glide phase. Secondly, the active phase takes the longest range as the performance index, and the glide phase takes the maximum terminal velocity as the performance index. According to the constraints of flight process analysis, it establishes the optimal control model of trajectory optimization. Lastly, the Gauss pseudo-spectral method is used to plan the trajectory of the active and gliding phases. The simulation results show that the obtained trajectory characteristics are consistent with the high-throw-reentry-glide trajectory scheme, and the flight parameters satisfy the constraints. This study can provide some reference for the trajectory planning of the near-space interceptor.

This paper examines factors of payment decision as well as the role each factor plays in casual configurations leading to high payment intention under systematic and heuristic information processing routes.

Chemodynamic therapy (CDT) generating hydroxyl radicals (•OH) by utilizing metal ions reacting with hydrogen peroxide (H2O2) is a highly encouraging strategy for cancer treatment. However, highly expressed GSH in tumor cells severely limits the efficacy of CDT, and CDT alone is also not sufficient to produce excellent antitumor efficiency. Herein, a dual GSH depletion nanosystem (MnO2@PDA@PEG@DOX) was designed and synthesized to achieve synergistic cancer treatment under ultrasound (US) irritation. To achieve an acidic response, dopamine (DA) was loaded onto manganese dioxide, and the water solubility and stability were greatly improved after PEG modification; finally, the loading of doxorubicin (DOX) achieved the combinational therapy. When the nanoparticles arrived at the tumor site, the acidic and high expression of GSH in the tumor microenvironment prompted the degrading of the nanosystem, followed by the release of MnO2 and DOX. The released MnO2 can react with intracellular GSH to produce Mn2+, which realizes chemodynamic therapy by catalyzing H2O2 to generate highly toxic hydroxyl radicals (•OH) at the tumor site; also, the depletion of GSH will significantly promote the level of •OH, improving the efficiency of CDT simultaneously. Moreover, the release of DOX could be boosted by US irradiation, thus enhancing the effect of chemotherapy on DOX and achieving sonodynamic therapy (SDT). Therefore, strategies to enhance CDT efficiency by dual GSH depletion and combining chemotherapy and sonodynamic therapy modalities can provide more ideas and approaches for combination therapy in cancer treatment. [ABSTRACT FROM AUTHOR]