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Purpose: In order to investigate the vibration reduction properties of a three-dimensional elastic metastructure with spherical cavities at low frequencies. Design/methodology/approach: The bandgap characteristics of a three-dimensional elastic metastructure with spherical cavities are studied based on analytical and numerical approaches. Findings: The results of both method revealed that the vibration of the vertexes masses is important for opening bandgaps. The fact that the big sphere cavity radius or short side length of the cube unit leads to a wider bandgap, is noteworthy. Originality/value: This research provides theoretical guidance for realizing the vibration attenuation application of EMs in practical engineering.

Accurate detection of obstructive sleep apnea (OSA) with a single-lead electrocardiogram (ECG) signal is highly desirable for the timely treating of OSA patients. However, due to the variance of apneas in appearance and size in ECG signals, it is still a very challenging task to obtain an accurate OSA apnea detection. To address this problem, this article presents a time–frequency information fusion-based CNN-Transformer model (TFFormer) for OSA detection with single-lead ECG, in which a module consisting of a deep residual shrinkage module, a multiscale convolutional attention (MSCA) module, and a multilayer convolution module is developed for time–frequency feature extraction. The purpose of this operation is to extract rich features from a short length of ECG signal sequences with a low computation cost. For time–frequency information fusion, to reduce its computation cost, a gated self-attention-based adaptive pruning time–frequency information fusion attention module is developed to prune the redundant tokens. With the attention-based adaptive pruning time–frequency information fusion module, the TFFormer is constructed for data-parallel processing and long-distance modeling. Compared with the best model in the comparative method, the accuracy of the proposed method was improved by 0.18% in the segmented case, and the mean absolute error was reduced by 0.25 per-recorded case, which demonstrates that the TFFormer model has better OSA detection performance and could provide a convenient and accurate solution for clinical OSA detection.

Supplemental Digital Content is available in the text.Quality improvement and patient safety (QIPS) are core components of graduate medical education (GME). Training programs and affiliated medical centers must partner to create an environment in which trainees can learn while meaningfully contributing to QIPS efforts, to further the shared goal of improving patient care. Numerous challenges have been identified in the literature, including lack of resources, lack of faculty expertise, and siloed QIPS programs. In this article, the authors describe a framework for integrated QIPS training for residents in the University of Washington Internal Medicine Residency Program, beginning in 2014 with the creation of a dedicated QIPS chief resident position and assistant program director for health systems position, the building of a formal curriculum, and integration with medical center QIPS efforts. The postgraduate year (PGY) 1 curriculum focused on the culture of patient safety and entering traditional patient safety event (PSE) reports. The PGY-2 curriculum highlighted QIPS methodology and how to conduct mentored PSE reviews of cases that were of educational value to trainees and a clinical priority to the medical center. Additional PGY-2/PGY-3 training focused on the active report, presentation, and evaluation of cases during morbidity and mortality conferences while on clinical services, as well as how to lead longitudinal QIPS work. Select residents led mentored QI projects as part of an additional elective. The hallmark feature of this framework was the depth of integration with medical center priorities, which maximized educational and operational value. Evaluation of the program demonstrated improved attitudes, knowledge, and behavior changes in trainees, and significant contributions to medical center QIPS work. This specialty-agnostic framework allowed for training program and medical center integration, as well as horizontal integration across GME specialties, and can be a model for other institutions.

The laser cleaning effect can be affected by many parameters, including laser power, scanning speed, laser repetition rate, and pulse duration, and the cleaning effect with these parameters is investigated. It is found that the cleaning effect is negligible for an infrared high-repetition nanosecond-pulsed laser with repetition rate from 100 to 400 kHz and pulse duration from 58 to 240 ns and is significantly related to the laser power and scanning speed. Moreover, the cleaning thresholds related to laser power and scanning speed for a soil rust layer on ceramic artifacts are measured under the step distance of 281.3 μm. The heat conduction equation and thermal stress equation are used to simulate the cleaning effect with the influence of these parameters, which is in good agreement with the experimental data.

Ferroptosis is an iron-mediated, caspase-independent pathway of cell death that is accompanied with the accumulations of reactive oxygen species (ROS) and oxygenases, as well as being involved in many other pathophysiological procedures. However, specific and rapid monitoring of ferroptosis in living cells or tissues has not been achieved so far. Herein, a quinoxalinone-based fluorescent probe (termed as Quinos-4, or QS-4) with a reactive aromatic thioether moiety was designed for ferroptosis identification. Upon exposing it to high levels of ROS and hemeoxygenase-1 (HO-1), which are considered as the biochemical characteristics of ferroptosis, QS-4 could be oxidized into a sulfoxide derivative (QSO-4) and its original aggregation-induced enhanced red fluorescence emission could be converted to green fluorescence emission sharply. On the basis of this unique reaction-induced color conversion, this molecular probe can be employed for identifying the occurrence of ferroptosis both in vitro and in vivo.

Recent years have witnessed the great contributions that drug combination therapy has made for enhanced cancer therapy. However, because of the complicated pharmacokinetics of combined drug formulations, the majority of combination strategies show severe adverse effects at high dosage and poor biodistribution in vivo. To overcome these deficiencies and achieve enhanced cancer therapy, we put forward a method to construct a smart albumin-based nanoplatform, denoted as K237-HSA-DC, for codelivery of cyclooxygenase-2 (COX-2) inhibitor (celecoxib) and chemotherapeutic agent (doxorubicin, DOX). Both in vitroand in vivostudies indicate that K237-HSA-DC exhibits the best therapeutic efficacy on tumor cells compared with all the other formulations. Moreover, K237-HSA-DC shows fewer side effects on normal organs in contrast to other formulations. To understand the reasons behind the improved drug efficacy in depth, we performed a cell metabonomics-based mechanism study and found that celecoxib could enhance the inhibitory effect of DOX on the transport of glucose into cells and then lead to subsequent significant energy metabolism inhibition. Considering the above-mentioned advantages of K237-HSA-DC, we believe the smart albumin-based nanoplatform can serve as a promising drug delivery system for enhanced cancer therapy.

Polyethylene glycol (PEG) is widely used in the biomedical field due to its outstanding properties. There are plenty of reports on the safety of PEG, but they are mostly restricted to its pharmacokinetic behaviour and pathological effect in vivo, and fail to elucidate its biological effects on cells at the molecular level. Consequently, here we illuminate the biological effect of PEG on a specific cellular pathway. We found that PEG could induce short-term urea cycle inhibition in rat liver cells in vitrowithout damaging the mitochondria and cells, which was proven to be an adaptive and reversible response to PEG at the molecular level. PEG could also induce a transient hepatic stress response in vivo, which was closely related with the urea cycle disorder. As a mechanistic study on the interactions between a synthetic biomedical polymer and cells at the molecular level, our work provides novel insights into the biological effects of polymers on a cellular system and is fundamental to the development of biomedical polymers.

Nanoscale drug delivery systems (DDSs) are generally considered to be an effective alternative to small molecular chemotherapeutics due to improved accumulation in the tumor site and enhanced retention in blood. Nevertheless, most DDSs have low loading efficiency or even pose a high threat to normal organs from severe side effects. Ideally, a supramolecular drug–drug delivery system (SDDDS) composed of pure drugs via supramolecular interaction provides a hopeful approach for cancer treatment. Herein we propose a facile method to construct SDDDS via coassembly of gefitinib (GEF) and tripeptide tyroservatide (YSV), two kinds of chemotherapeutic pharmaceuticals for non-small-cell lung cancer (NSCLC) via multiple intermolecular interactions, including hydrogen bonding and π–π stacking. As shown through transmission electron microscopy (TEM) and dynamic light scattering (DLS), GEF and YSV self-assemble into nanoparticles with regular morphology and uniform size, which facilitates the delivery of both drugs. In vitro studies demonstrate that the SDDDS is much more efficient in entering cancer cells and inhibiting the proliferation of cancer cells compared with single GEF, YSV, or GEF/YSV drug mixture. In vivo experiments show that the SDDDS can selectively accumulate in tumor tissue, resulting in much better drug efficacy without evident side effects. Considering the advantages of the SDDDS, we believe this strategy provides a promising route for enhanced anticancer therapy in nanomedicine.

Background: As it is known that the access network is very sensitive to the cost, and the number of remote nodes (RNs) is large in metro-access network. RN cost occupies the main part of the whole network cost. Objective: Therefore, reducing the cost of RN is the key to improve the cost efficiency of the whole network. Method: In this paper, we only use some conventional optical components, such as optical switches, circulators and couplers, to design a simple low-cost structure of remote node (RN) for large-scale metro- access network based on dual-fiber ring. Results: By adopting symmetrical structure of RN in this design, the network cannot only carry out mutual protections between dual fibers, but also further decreases its operation and maintenance costs. In addition, the RN based on the structure has also the function of broadcasting services. Conclusion: Finally, feasibility of the structure has been demonstrated by simulation and analysis.

AbstractIn this paper, the general structural models of single-fiber bidirectional wavelength division multiplexing passive optical network with star topology and ring topology are proposed. The performances of the two general structural models including network scale, construction cost and system reliability, are analyzed and compared numerically. In particular, link failure and node failure are considered as two different types of failures and discussed separately in the context. The characteristics of the two models, which are concluded in the end of this paper, can be the guide in the deployment of WDM-PON.