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Nonlinear energy sinks (NES) have been shown to have broadband absorption for multiple modes. Furthermore, linear dynamic absorbers (LDA) often only operate effectively within located frequency ranges and are unable to achieve broadband absorption. Therefore, this manuscript first proposed using a hybrid LDA and NES to design the circular ring absorption system. Compared with LDA, broadband absorption could be achieved through configuring and tuning linear stiffness. Both the linear and nonlinear stiffnesses are introduced by adding vertical and horizontal springs. The linear and nonlinear stiffness effects on the circular ring absorption system are investigated simultaneously. The dynamic model of the circular ring absorption system with hybrid LDA and NES is constructed, and the approximate analytical solution is obtained using the harmonic balance analysis. The expressions of frequency response and force transmissibility are given, and the analytical results are verified numerically. By comparing the amplitude-frequency response curves of the circular ring with LDA only, NES only, and a hybrid LDA and NES, it is confirmed that a hybrid LDA and NES can better control the forced vibration of the circular ring absorption system. Hybrid LDA and NES were shown to suppress main resonance peaks of the circular ring absorption system, making the device resistant to misalignments. In a linear system, this can only be achieved by resonance matching, so a hybrid LDA and NES have the same effect as adding multiple linear absorbers. Some properties of damping, nonlinear stiffness, and mass ratios in a hybrid LDA and NES are investigated. These parameters determine the specific shape of the force transmissibility curve of the ring absorption system. It is found that a proper increase in the mass ratio of the hybrid LDA and NES can obtain a better vibration reduction effect; adjusting the damping ratio and nonlinear stiffness ratio of the hybrid LDA and NES can improve the vibration reduction effect to a certain extent. Based on the analysis of the parameters effects of hybrid LDA and NES on vibration control, the parameters of hybrid LDA and NES are compared. The analysis of the results demonstrates that by selecting reasonable damping, nonlinear stiffness, and mass ratios, the frequency band of the circular ring absorption system can be broadened. Finally, an experiment is performed to validate the correctness of the proposed method. [ABSTRACT FROM AUTHOR]

Nonbenzenoid polycyclic arenes have attracted great attention because of their unique topological structures and appealing properties; however, they are generally considered as poor luminescent materials due to the ring puckering behavior of the nonhexagons. Acepleiadylene (APD), a nonbenzenoid isomer of pyrene, has been demonstrated as an excellent building block for optoelectronic applications, but its poor photoluminescence quantum yield (PLQY) has hampered its application in luminescent materials. Considering that the ring puckering character can be suppressed by increasing the rigidity of the nonhexagon rings, herein, we propose a novel strategy for enhancing the aromaticity of the nonhexagons to improve the PLQYs of APD derivatives. Electron-withdrawing cyano groups are introduced on the five-membered ring of APD to enhance the charge-separated character and thus the aromaticity of the nonhexagons, endowing the cyano-substituted APDs (CNAPD and 2CNAPD) with better rigidity. Therefore, the cyano substitution successfully suppresses the nonradiative energy dissipation caused by the ring puckering, improving the PLQY from 2.4% for APD to 14% for CNAPD, and to 63% for 2CNAPD. In addition, the enhanced rigidity also suppresses the vibration sideband of the photoluminescence spectra, leading to an ultra-narrowband emission from 2CNAPD with a full-width at half-maximum (FWHM) of 13 nm (47 meV), which is a new record in organic molecules. These results demonstrate that APD derivatives have great potential in highly efficient luminescent materials with high color purity via the aromaticity regulation strategy, which provides a novel concept for designing nonbenzenoid luminescent materials. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) tumours carry multiple gene mutations and respond poorly to treatments. There is currently an unmet need for drug carriers that can deliver multiple gene cargoes to target high solid tumour burden like PDAC. Here, we report a dual targeted extracellular vesicle (dtEV) carrying high loads of therapeutic RNA that effectively suppresses large PDAC tumours in mice. The EV surface contains a CD64 protein that has a tissue targeting peptide and a humanized monoclonal antibody. Cells sequentially transfected with plasmid DNAs encoding for the RNA and protein of interest by Transwell®-based asymmetric cell electroporation release abundant targeted EVs with high RNA loading. Together with a low dose chemotherapy drug, Gemcitabine, dtEVs suppress large orthotopic PANC-1 and patient derived xenograft tumours and metastasis in mice and extended animal survival. Our work presents a clinically accessible and scalable way to produce abundant EVs for delivering multiple gene cargoes to large solid tumours. KRASG12D mutations frequently co-occur with mutated TP53 tumour suppressor in patients with pancreatic ductal adenocarcinoma (PDAC). Here the authors report the design of dual targeted therapeutic extracellular vesicles containing high copy numbers of TP53 mRNA and siKRASG12D, showing anti-tumor activity in PDAC preclinical models. [ABSTRACT FROM AUTHOR]

Background: Basilar invagination (BI) is a common disease in the craniocervical junction (CVJ) area. Posterior fossa decompression with/without fixation is a controversial surgical strategy for BI type B. This study aimed to evaluate the efficacy of simple posterior fossa decompression in treating BI type B. Methods: This study retrospectively enrolled BI type B patients who underwent simple posterior fossa decompression at Huashan Hospital, Fudan University between 2014.12 and 2021.12. Patient data and images were recorded pre- and postoperatively (at the last follow-up) to evaluate the surgical outcomes and craniocervical stability. Results: A total of 18 BI type B patients (13 females), with a mean age of 44.2±7.9 years (range 37–62 years), were enrolled. The mean follow-up period was 47.7±20.6 months (range 10–81 months). All patients received simple posterior fossa decompression without any fixation. At the last follow-up, compared with preoperation, the JOA scores were significantly higher (14.2±1.5 vs. 9.9±2.0, p = 0.001); the CCA was improved (128.7±9.6° vs. 121.5±8.1° p = 0.001), and the DOCL was reduced (7.9±1.5 mm vs. 9.9±2.5 mm, p = 0.001). However, the follow-up and preoperative ADI, BAI, PR, and D/L ratio were similar. No patients had an unstable condition between the C1-2 facet joints that was observed in the follow-up CT and dynamic X-ray. Conclusions: In BI type B patients, simple posterior fossa decompression could improve neurological function and will not induce CVJ instability in BI type B patients. Simple posterior fossa decompression could be a satisfactory surgical strategy for BI type B patients, but preoperative CVJ stability assessment is crucial. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel type of polyacid corrosion inhibitor (PCI) was synthesized from the residue of 2-vinylpyridine, which could reduce the cost of hazardous waste disposal in production enterprises, and solve the environmental pollution caused by residue. Herein, the components of the residue were analyzed and a special solvent is selected to dissolve it. Then, synergistic experiments of the residual solution with different inhibitor were carried out to select the corrosion inhibitor components, and the optimal ratio of each component was determined by orthogonal experiments. The performance of PCI was estimated by weight loss method, and its electrochemical type was detected by electrochemical experiments. It indicated that the main components of 2-vinylpyridine residue are pyridine derivatives and hydrocarbons. The developed PCI is composed by four components, which could be suitable for HCl, citric acid, sulfamic acid, other acid systems, and has good corrosion inhibition effect on carbon steel, brass, and other materials. The corrosion rate of N80 carbon steel can reach to 0.5491 g m−2 h−1 at 60 ℃ in 5% HCl, which fully meets the requirements of China national standards. The electrochemical polarization curve showed that PCI is a kind of highly effective mixed inhibitor, which can inhibit both cathode and anode simultaneously. [ABSTRACT FROM AUTHOR]

Secret sharing is a widely-used security protocol and cryptographic primitive in which all people cooperate to restore encrypted information. The characteristics of a quantum field guarantee the security of information; therefore, many researchers are interested in quantum cryptography and quantum secret sharing (QSS) is an important research topic. However, most traditional QSS methods are complex and difficult to implement. In addition, most traditional QSS schemes share classical information, not quantum information which makes them inefficient to transfer and share information. In a weighted threshold QSS method, each participant has each own weight, but assigning weights usually costs multiple quantum states. Quantum state consumption will therefore increase with the weight. It is inefficient and difficult, and therefore not able to successfully build a suitable agreement. The proposed method is the first attempt to build multiparty weighted threshold QSS method using single quantum particles combine with the Chinese remainder theorem (CRT) and phase shift operation. The proposed scheme allows each participant has its own weight and the dealer can encode a quantum state with the phase shift operation. The dividing and recovery characteristics of CRT offer a simple approach to distribute partial keys. The reversibility of phase shift operation can encode and decode the secret. The proposed weighted threshold QSS scheme presents the security analysis of external attacks and internal attacks. Furthermore, the efficiency analysis shows that our method is more efficient, flexible, and simpler to implement than traditional methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim:Receptor-interacting protein 3 (RIP3) is involved in tumor necrosis factor receptor signaling, and results in NF-κB-mediated prosurvival signaling and programmed cell death. The aim of this study was to determine whether overexpression of the RIP3 gene could sensitize human breast cancer cells to parthenolide in vitro.Methods:The expression of RIP3 mRNA in human breast cancer cell lines (MCF-7, MDA-MB-231, MDA-MB-435 and T47D) was detected using RT-PCR. Both MDA-MB-231 and MCF-7 cells were transfected with RIP3 expression or blank vectors via lentivirus. Cell viability was measured with MTT assay; intracellular ROS level and cell apoptosis were analyzed using flow cytometry.Results:RIP3 mRNA expression was not detected in the four human breast cancer cell lines tested. However, the transfection induced higher levels of RIP3 protein in MCF-7 and MDA-MB-231 cells. Furthermore, overexpression of RIP3 decreased the IC50 values of parthenolide from 17.6 to 12.6 μmol/L in MCF-7 cells, and from 16.6 to 9.9 μmol/L in MDA-MB-231 cells. Moreover, overexpression of RIP3 significantly increased parthenolide-induced apoptosis and ROS accumulation in MCF-7 and MDA-MB-231 cells. Pretreatment with N-acetyl-cysteine abrogated the increased sensitivity of RIP3-transfected MCF-7 and MDA-MB-231 cells to parthenolide.Conclusion:Overexpression of RIP3 sensitizes MCF-7 and MDA-MB-231 breast cancer cells to parthenolide in vitro via intracellular ROS accumulation. [ABSTRACT FROM AUTHOR]