The 3D printing technology has evolved impressively over the last decade in its ability to fabricate structures with complex architectures at the micro- and macroscale. 3D printing of high explosive ...would reduce the unnecessary process for excessive handling, post-processing, and stockpiling confers benefits to safety, cost, waste, and flexibility. To truly take advantage of direct writing technology, materials and inks are allowed for fast and reliable deposition. Herein, 3D printable ink based on CL-20/HTPB was designed and printed. The explosive ink exhibited high performance, validating the potential of fully 3D printed structures with high performance of combustion. The method can print complex geometries with well-defined dimensions. To achieve high-quality printing with continuous ink, the uniformities were further optimized by tuning the concentrations of the CL-20, and the binder rate to curing agent. With the aid of 3D printing, various novel applications and functionalities became accessible, which is beyond the limits of conventional charge process (press loading and casting curing). This approach makes printing of diverse patterns possible, which open new avenues to fabricate gradient structure explosive and propellant with tunable safe combustion and detonation properties.
Organic field‐effect transistors and near‐infrared (NIR) organic phototransistors (OPTs) have attracted world's attention in many fields in the past decades. In general, the sensitivity, ...distinguishing the signal from noise, is the key parameter to evaluate the performance of NIR OPTs, which is decided by responsivity and dark current. 2D single crystal films of organic semiconductors (2DCOS) are promising functional materials due to their long‐range order in spite of only few molecular layers. Herein, for the first time, air‐stable 2DCOS of n‐type organic semiconductors (a furan‐thiophene quinoidal compound, TFT‐CN) with strong absorbance around 830 nm, by the facile drop‐casting method on the surface of water are successfully prepared. Almost millimeter‐sized TFT‐CN 2DCOS are obtained and their thickness is below 5 nm. A competitive field‐effect electron mobility (1.36 cm2 V−1 s−1) and high on/off ratio (up to 108) are obtained in air. Impressively, the ultrasensitive NIR phototransistors operating at the off‐state exhibit a very low dark current of ≈0.3 pA and an ultrahigh detectivity (D*) exceeding 6 × 1014 Jones because the devices can operate in full depletion at the off‐state, superior to the majority of the reported organic‐based NIR phototransistors.
High‐performance organic field‐effect transistors and near‐infrared phototransistors with n‐type two‐dimensional organic single crystals are successfully fabricated. A field‐effect electron mobility (1.36 cm2 V−1 s−1) and high on/off ratio (108) are obtained. Impressively, the ultrasensitive near‐infrared phototransistors exhibit an ultrahigh detectivity exceeding 6 × 1014 Jones, superior to the majority of the reported organic‐based near‐infrared phototransistors.
The furan–thiophene‐based quinoidal organic semiconductor, TFT‐CN, is designed and synthesized. TFT‐CN displays a high electron mobility of 7.7 cm2 V−1 s−1, two orders of magnitude higher than the ...corresponding thiophene‐based derivative.
Aldehyde dehydrogenase 7 family member A1 (ALDH7A1) is an enzyme catalyzing lipid peroxidation of fatty aldehydes. It plays a critical role in sustaining high oxygen consumption rate (OCR) and ATP ...production in pancreatic ductal adenocarcinoma (PADC). However, why PADC cells maintain a relatively high level of ALDH7A1 concentration is still not well understood. In the current study, we explored the interplay between epidermal growth factor receptor kinase substrate 8 (EPS8) and ALDH7A1 in PADC cells. PADC cell lines MIA PaCa-2 and AsPANC-1 were used for in vitro and in vivo studies. The co-IP assay showed mutual interactions between Flag-EPS8 and Myc-ALDH7A1 in both MIA PaCa-2 and AsPANC-1 cells. EPS8 knockdown resulted in decreased ALDH7A1 protein levels and increased poly-ubiquitination. An interaction was observed between ALDH7A1 and BMI1 but not between BMI1 and EPS8. BMI1 knockdown reduced ALDH7A1 poly-ubiquitination and degradation caused by EPS8 knockdown. Dual EPS8 and ALDH7A1 knockdown had a synergistic effect on suppressing PADC cell proliferation in vitro and in vivo. In conclusion, this study revealed that EPS8 supports PADC growth by interacting with ALDH7A1 and inhibiting BMI1 mediated proteasomal degradation of ALDH7A1.
Signal transducer and activator of transcription 3 (STAT3) and nuclear factor erythroid-derived 2-like 2 (NRF2, also known as NFE2L2), are two of the most complicated transcription regulators, which ...participate in a variety of physiological processes. Numerous studies have shown that they are overactivated in multiple types of tumors. Interestingly, STAT3 and NRF2 can also interact with each other to regulate tumor progression. Hence, these two important transcription factors are considered key targets for developing a new class of antitumor drugs. This review summarizes the pivotal roles of the two transcription regulators and their interactions in the tumor microenvironment to identify potential antitumor drug targets and, ultimately, improve patients' health and survival.
The vulnerability of weapon and ammunition has been attracting more and more researcher’s attention in order to improve their system survival in battlefield and security of production, transport and ...service management, and to adapt to the harsh battlefield environment. One of potential directions of explosive research and development is to reduce its vulnerability through charging structures. RDX-based high aluminized gradient structures explosives are constructed via direct ink writing. SEM and DSC demonstrated good compatibility of the gradient explosives and no significant gaps at the interface of the filaments, which leads to good thermal stability and suppressed hot spot formation within the gradient explosive. The critical dimension of detonation indicates that the critical size of explosive with gradient structure is greatly increased. This attractive integration of structural and functional advantages achieved by 3D printing gradient structure process offers new insights into the design of robust munitions.
Nanothermites and high-energy explosives have significantly improved the performance of high-energy composites and have broad application prospects. Therefore, in this study, RDX/F2311/Fe2O3/Al ...composite hollow microspheres were successfully prepared utilizing the electrospray method using F2311 as a binder between components. The results show that the combustion time of the composite hollow microspheres is shortened from 2400 ms to 950 ms, the combustion process is more stable, and the energy release is more concentrated. The H50 of the composite hollow microspheres increased from 14.49 cm to 24.57 cm, the explosion percentage decreased from 84% to 72%, and the sensitivity of the composite samples decreased significantly. This is mainly the result of the combination of homogeneous composition and synergistic reactions. The combustion results show that F2311 as a binder affects the tightness of the contact between the components. By adjusting its content, the combustion time and the intensity of the combustion of the composite microspheres can be adjusted, which provides a feasible direction for its practical application.
Many species of bats rely on echoes to forage and navigate in densely vegetated environments. Foliage echoes in some cases can help bats gather information about the environment, whereas in others ...may generate clutter that can mask prey echoes during foraging. It is therefore important to study foliage echoes and their role in bat's sensory ecology. In our prior work, a foliage echo simulator has been developed; simulated echoes has been compared with field recordings using a biomimetic sonar head. In this work, we improve the existing simulator by allowing more flexible experimental setups and enabling a closer match with the experiments. Specifically, we add additional features into the simulator including separate directivity patterns for emitter and receiver, the ability to place emitter and receiver at distinct locations, and multiple options to orient the foliage to mimic natural conditions like strong wind. To study how accurately the simulator can replicate the real echo-generating process, we compare simulated echoes with experimental echoes measured by ensonifying a single leaf across four different species of trees. We further extend the prior work on estimating foliage parameters to estimating a map of the environment.
Abstract
Depression has become one of the most common mental illnesses in the world. For better prediction and diagnosis, methods of automatic depression recognition based on speech signal are ...constantly proposed and updated, with a transition from the early traditional methods based on hand‐crafted features to the application of architectures of deep learning. This paper systematically and precisely outlines the most prominent and up‐to‐date research of automatic depression recognition by intelligent speech signal processing so far. Furthermore, methods for acoustic feature extraction, algorithms for classification and regression, as well as end to end deep models are investigated and analysed. Finally, general trends are summarised and key unresolved issues are identified to be considered in future studies of automatic speech depression recognition.
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•CoMn-alginate/AP composite was successfully prepared by a facile approach.•CoMn-alginate had a 3D network structure with pores and some thin nanosheets.•As temperature rising, ...CoMn-alginate was decomposed into in-situ grown nanoparticle.•The thermal decomposition temperature of AP was significantly reduced by 122.9 ℃.•Possible synergistic mechanism for the thermal decomposition of AP was proposed.
An excellent material for thermal decomposition of ammonium perchlorate (AP) is urgently required. Herein, inspired by natural biopolymer, we prepared CoMn–alginate/AP composite by air atomization method. The results clearly indicated that the bimetallic CoMn–alginate had a 3D network structure consisting of pores and some thin nanosheets. With increasing temperature, the bimetallic CoMn–alginate was decomposed and formed MnCo2O4 nanoparticles by in situ growth. These MnCo2O4 nanoparticles had better catalytic activity for thermal decomposition of AP. In addition, we investigated the effect of using different mass ratios of AP and sodium alginate (SA) and different molar ratios of Co(NO3)2 and Mn(NO3)2 on catalytic thermal decomposition of AP. Notably, the thermal decomposition temperature was decreased by 122.9 °C. Furthermore, we also proposed a possible synergistic mechanism. All the results indicated that the bimetallic CoMn–alginate had a greater synergistic effect on thermal decomposition of AP.
