The slow rate of extracellular electron transfer (EET) of electroactive microorganisms remains a primary bottleneck that restricts the practical applications of bioelectrochemical systems. ...Intracellular NAD(H/
) (i.e., the total level of NADH and NAD
) is a crucial source of the intracellular electron pool from which intracellular electrons are transferred to extracellular electron acceptors via EET pathways. However, how the total level of intracellular NAD(H/
) impacts the EET rate in Shewanella oneidensis has not been established. Here, we use a modular synthetic biology strategy to redirect metabolic flux towards NAD
biosynthesis via three modules: de novo, salvage, and universal biosynthesis modules in S. oneidensis MR-1. The results demonstrate that an increase in intracellular NAD(H/
) results in the transfer of more electrons from the increased oxidation of the electron donor to the EET pathways of S. oneidensis, thereby enhancing intracellular electron flux and the EET rate.
Reliable and noninvasive biomarkers for the early diagnosis of non‐small‐cell lung cancer (NSCLC) are an unmet need. This study aimed to screen and validate potential urinary biomarkers for the early ...diagnosis of NSCLC. Using protein mass spectrometry, urinary MDH2 was found to be abundant both in patients with lung cancer and lung cancer model mice compared with controls. Urine samples obtained as retrospective and prospective cohorts including 1091 NSCLC patients and 736 healthy controls were measured using ELISA. Patients with stage I NSCLC had higher urinary MDH2 compared with healthy controls. The area under the receiver‐operating characteristic curve (AUC) for the urinary MDH2 was 0.7679 and 0.7234 in retrospective and prospective cohorts to distinguish stage I cases from controls. Urinary MDH2 levels correlated with gender and smoking history. MDH2 expression levels were elevated in lung cancer tissues. MDH2 knockdown using shRNA inhibited the proliferation of lung cancer cells. Our study demonstrated that urinary MDH2 concentration was higher in early‐stage NSCLC patients compared with that in controls and that MDH2 could serve as a potential biomarker for early detection of NSCLC.
Malate dehydrogenase 2 was significantly elevated both in urine and in cancer tissues of NSCLC patients. The level of MDH2 in urine could serve as an assistant biomarker for the early diagnosis of NSCLC.
The safety issue of lithium‐ion batteries is a crucial factor limiting their large‐scale application. Therefore, it is of practical significance to evaluate the impact of their overcharge behavior ...because of the severe levels of oxygen release of cathode materials during this process. Herein, by combining a variety of in situ techniques of spectroscopy and electron microscopy, this work studies the structural degradation of LiNi0.8Co0.1Mn0.1O2 (NCM811) accompanying the oxygen release in the overcharge process. It is observed that a small amount of O2 evolves from the initial surface at ≈4.7 V. When charging to a higher voltage (≈5.5 V), a large amount of O2 evolves on the newly formed surface due to the occurrence of microcracks. Based on experimental results and theoretical calculations, it is determined that the oxygen release mainly occurs in the near‐surface regions, where the remaining oxygen vacancies accumulate to create voids. To suppress the oxygen release, single‐crystalline NCM811 with integrated structure is introduced and serves as a cathode, which can effectively inhibit morphology destruction and reduce the activation of lattice oxygen in the surface region. These findings provide a theoretical basis and effective strategy for improving the safety performance of Ni‐rich cathode materials in practical applications.
Safety issues hinder the commercialization of Ni‐rich cathode materials. Oxygen release occurs from different regions during the overcharge process as shown by several in situ spectroscopy techniques and electron microscopy. O2 appears first in the near‐surface region of secondary particles, then on the fresh surface between primary particles due to the occurrence of microcracks. Single‐crystalline NCM811 with integrated structure could reduce this phenomenon.
Computed tomography (CT) is widely used in medical diagnosis and non-destructive detection. Image reconstruction in CT aims to accurately recover pixel values from measured line integrals, i.e., the ...summed pixel values along straight lines. Provided that the acquired data satisfy the data sufficiency condition as well as other conditions regarding the view angle sampling interval and the severity of transverse data truncation, researchers have discovered many solutions to accurately reconstruct the image. However, if these conditions are violated, accurate image reconstruction from line integrals remains an intellectual challenge. In this paper, a deep learning method with a common network architecture, termed iCT-Net, was developed and trained to accurately reconstruct images for previously solved and unsolved CT reconstruction problems with high quantitative accuracy. Particularly, accurate reconstructions were achieved for the case when the sparse view reconstruction problem (i.e., compressed sensing problem) is entangled with the classical interior tomographic problems.
Many metal–organic cages (MOCs) and a few hydrogen‐bonded organic cages (HOCs) have been investigated, but little is reported about cooperative self‐assembly of MOCs and HOCs. Herein, we describe an ...unprecedented MOC&HOC co‐crystal composed of tetrahedral Ti4L6 (L=embonate) cages and in‐situ‐generated (NH3)4(TIPA)4 (TIPA=tris(4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl)amine) cages. Chiral transfer is observed from the enantiopure Ti4L6 cage to enantiopure (NH3)4(TIPA)4 cage. Two homochiral supramolecular frameworks with opposite handedness (PTC‐235(Δ) and PTC‐235(Λ)) are formed. Such MOC&HOC co‐crystal features high stability in water and other solvents, affording single‐crystal‐to‐single‐crystal transformation to trap CH3CN molecules and identify disordered NH4+ cations. A tablet pressing method is developed to test the third‐order nonlinear optical property of KBr‐based PTC‐235 thin film. Such a thin film exhibits an excellent optical limiting effect.
The supramolecular self‐assembly between metal–organic cages (MOCs) and hydrogen‐bonded organic cages (HOCs) is realized in an MOC&HOC co‐crystal composed of tetrahedral Ti4L6 cages and (NH3)4(TIPA)4 cages generated in situ. The MOC&HOC co‐crystal thin film exhibits an excellent optical limiting effect.
Gasdermin E (GSDME) has an important role in inducing secondary necrosis/pyroptosis. Upon apoptotic stimulation, it can be cleaved by activated caspase-3 to generate its N-terminal fragment ...(GSDME-NT), which executes pyroptosis by perforating the plasma membrane. GSDME is expressed in many human lung cancers including A549 cells. Paclitaxel and cisplatin are two representative chemotherapeutic agents for lung cancers, which induce apoptosis via different action mechanisms. However, it remains unclear whether they can induce GSDME-mediated secondary necrosis/pyroptosis in lung A549 cancer cells. Here we showed that both paclitaxel and cisplatin evidently induced apoptosis in A549 cells as revealed by the activation of multiple apoptotic markers. Notably, some of the dying cells displayed characteristic morphology of secondary necrosis/pyroptosis, by blowing large bubbles from the cellular membrane accompanied by caspase-3 activation and GSDME-NT generation. But the ability of cisplatin to induce this phenomenon was much stronger than that of paclitaxel. Consistent with this, cisplatin triggered much higher activation of caspase-3 and generation of GSDME-NT than paclitaxel, suggesting that the levels of secondary necrosis/pyroptosis correlated with the levels of active caspase-3 and GSDME-NT. Supporting this, caspase-3 specific inhibitor (Ac-DEVD-CHO) suppressed cisplatin-induced GSDME-NT generation and concurrently reduced the secondary necrosis/pyroptosis. Besides, GSDME knockdown significantly inhibited cisplatin- but not paclitaxel-induced secondary necrosis/pyroptosis. These results indicated that cisplatin induced higher levels of secondary necrosis/pyroptosis in A549 cells than paclitaxel, suggesting that cisplatin may provide additional advantages in the treatment of lung cancers with high levels of GSDME expression.
Photosensitization associated with light absorption and energy/electron‐transfer represents the central processes for photosynthesis. However, it's still a challenge to develop a heavy‐atom‐free ...(HAF) strategy to improve the sensitizing ability of polymeric photosensitizers. Herein, we propose a new protocol to significantly improve the photosensitization by decorating mother conjugated microporous polymer (CMP‐1) with polycyclic aromatic hydrocarbons (PAHs), resulting in a series of CMPs (CMP‐2–4). Systematic study reveals that covalent modification with PAHs can transfer charge to Bodipy in CMP to further facilitate both intersystem crossing and electron‐hole separation, which can dramatically boost energy‐/electron‐transfer reactions. Remarkably, CMP‐2 as a representative CMP can efficiently drive the photosynthesis of methyl phenyl sulfoxide with 92 % yield, substantially higher than that of CMP‐1 (32 %). Experiments and theory calculations demonstrate the structure‐property‐activity relationship of these CMPs, opening a new horizon for developing HAF heterogeneous photosensitizers with highly efficient sensitizing activity by rational structure regulation at a molecular level.
A proof‐of‐concept strategy to trigger charge transfer for improving photosensitization is the covalent modification of conjugated microporous polymers (CMPs) with polycyclic aromatic hydrocarbons (PAHs). Charge transfer from the PAH donor to the Bodipy acceptor in CMPs can facilitate both intersystem crossing and electron–hole separation, leading to excellent performance for both energy‐ and electron‐transfer reactions.
Despite their advantageous morphological attributes and attractive physicochemical properties, mesoporous silica nanoparticles (MSNs) are merely supported as carriers or vectors for a reason. ...Incorporating various metal species in the confined nanospaces of MSNs (M‐MSNs) significantly enriches their mesoporous architecture and diverse functionalities, bringing exciting potentials to this burgeoning field of research. These incorporated guest species offer enormous benefits to the MSN hosts concerning the reduction of their eventual size and the enhancement of their performance and stability, among other benefits. Substantially, the guest species act through contributing to reduced aggregation, augmented durability, ease of long‐term storage, and reduced toxicity, attributes that are of particular interest in diverse fields of biomedicine. In this review, the first aim is to discuss the current advancements and latest breakthroughs in the fabrication of M‐MSNs, emphasizing the pros and cons, the confinement of various metal species in the nanospaces of MSNs, and various factors influencing the encapsulation of metal species in MSNs. Further, an emphasis on potential applications of M‐MSNs in various fields, including in adsorption, catalysis, photoluminescence, and biomedicine, among others, along with a set of examples is provided. Finally, the advances in M‐MSNs with perspectives are summarized.
Despite their captivating physicochemical properties, mesoporous silica nanoparticles are only supported as carriers. To enrich their performance, various metal species are encapsulated in their nanospaces for diverse functionalities. This review provides an overview highlighting the attractive features of these innovative constructs and a synopsis of the current advancements and latest breakthroughs in their potential catalytic and various biomedical applications.
Separable nonlinear least-squares (SNLLS) problems arise frequently in many research fields, such as system identification and machine learning. The variable projection (VP) method is a very powerful ...tool for solving such problems. In this paper, we consider the regularization of ill-conditioned SNLLS problems based on the VP method. Selecting an appropriate regularization parameter is difficult because of the nonlinear optimization procedure. We propose to determine the regularization parameter using the weighted generalized cross-validation method at every iteration. This makes the original objective function changing during the optimization procedure. To circumvent this problem, we use an inequation to produce a consistent demand of decreasing at successive iterations. The approximation of the Jacobian of the regularized problem is also discussed. The proposed regularized VP algorithm is tested by the parameter estimation problem of several statistical models. Numerical results demonstrate the effectiveness of the proposed algorithm.
Trace Analysis Model of Muzzle Smoke Yan, Chen‐guang; Zhang, Ming‐xing; Li, Yan ...
Propellants, explosives, pyrotechnics,
July 2022, 2022-07-00, 20220701, Letnik:
47, Številka:
7
Journal Article
Recenzirano
Quantitative assessment of the harmful phenomenon of medium and large‐caliber muzzle smoke provides crucial support for the development of advanced propellants. Based on the current maximum area ...method and integration method of transmittance curve of examining muzzle smoke, the Trace Analysis Model of Muzzle Smoke (TAMMS) is proposed. First, based on the characteristics of few mass exchanges and relatively fixed expansion center of muzzle smoke cloud formed by high‐pressure release with the slow‐release zone, a muzzle smoke characteristic quantity model refers to the area and the concentration corresponding to each other was established. Secondly, a test system was built to experimentally verify the smoke characteristic quantity model, and the test error analysis was carried out. The research results show that the Trace Analysis Model of Muzzle Smoke takes into account the relationship between smoke area and transmittance over time and can more ideally characterize the muzzle smoke volume. The results of parallel testing and analysis of 7 sets of traditional 35 mm guns show good reproducibility, with a measurement uncertainty less than 0.5 dB.
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