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Genetic regulatory networks (GRNs) regulate the flow of genetic information from the genome to expressed messenger RNAs (mRNAs) and thus are critical to controlling the phenotypic characteristics of cells. Numerous methods exist for profiling mRNA transcript levels and identifying protein-DNA binding interactions at the genome-wide scale. These enable researchers to determine the structure and output of transcriptional regulatory networks, but uncovering the complete structure and regulatory logic of GRNs remains a challenge. The field of GRN inference aims to meet this challenge using computational modeling to derive the structure and logic of GRNs from experimental data and to encode this knowledge in Boolean networks, Bayesian networks, ordinary differential equation (ODE) models, or other modeling frameworks. However, most existing models do not incorporate dynamic transcriptional data since it has historically been less widely available in comparison to "static" transcriptional data. We report the development of an evolutionary algorithm-based ODE modeling approach (named EA) that integrates kinetic transcription data and the theory of attractor matching to infer GRN architecture and regulatory logic. Our method outperformed six leading GRN inference methods, none of which incorporate kinetic transcriptional data, in predicting regulatory connections among TFs when applied to a small-scale engineered synthetic GRN in Saccharomyces cerevisiae. Moreover, we demonstrate the potential of our method to predict unknown transcriptional profiles that would be produced upon genetic perturbation of the GRN governing a two-state cellular phenotypic switch in Candida albicans. We established an iterative refinement strategy to facilitate candidate selection for experimentation; the experimental results in turn provide validation or improvement for the model. In this way, our GRN inference approach can expedite the development of a sophisticated mathematical model that can accurately describe the structure and dynamics of the in vivo GRN. Author summary: The establishment of distinct transcriptional programs, where specific sets of genes are activated or repressed, is fundamental to all forms of life. Sequence-specific DNA-binding proteins, often referred to as regulatory transcription factors, form interconnected gene regulatory networks (GRNs) which underlie the establishment and maintenance of specific transcriptional programs. Since their discovery, many modeling approaches have sought to understand the structure and regulatory behaviors of these GRNs. The field of GRN inference uses experimental measurements of transcript abundance to predict how regulatory transcription factors interact with their downstream target genes to establish specific transcriptional programs. However, most prior approaches have been limited by the exclusive use of "static" or steady-state measurements. We have developed a unique approach which incorporates dynamic transcriptional data into a sophisticated ordinary differential equation model to infer GRN structures that give rise to distinct transcriptional programs. Our model not only outperforms six other leading models, it also is capable of accurately predicting how changes in GRN structure will impact the resulting transcriptional programs. These notable features of our model, in conjunction with experimental validation of our predictions in real-world scenarios, contribute to an advancement in the field of gene regulatory network inference. [ABSTRACT FROM AUTHOR]

Structural color fabrication attracting significant interest for science and art is usually restricted by costly and time‐consuming structuring processes or inerasable characteristics of structures. Herein, by developing a universal, low‐cost technical solution—the nanosecond laser irradiation of ink (Solvent Black 7) layers coated on metal—laser‐induced heterogeneous permanent/erasable nanostructures (LIHPEN) are produced successfully on multiple metals, especially noble metals, without ablation damage to intrinsic surfaces. LIHPEN consist of uniform laser‐induced periodic surface structures produced by surface plasmon polariton excitation of metals and can be extended into 2D hybrid micro/nanostructures by introducing the direct laser interference patterning technique. LIHPEN technology operated under a large processing parameter window can realize space‐selective erasability of prepared structures by controlling processing parameters, which determine the ink‐layer carbonization degree and thus the permanent or erasable characteristic. Because ink layers can be coated manually, in addition to realizing digital scanning patterns, LIHPEN technology can be integrated with traditional artistic techniques to solidify and color artworks without risk of information loss and leakage in digital copying. LIHPEN with good durability can exhibit vivid structural colors on metals, demonstrating its great potential in fields of artwork iridescent coloring, encryption, and anti‐counterfeiting, particularly those requiring customization, personalization, and rewritability. [ABSTRACT FROM AUTHOR]

Ferroptosis has been implicated in the pathogenesis of secondary brain injury following intracerebral hemorrhage (ICH), and regulating this process is considered a potential therapy for alleviating further brain injury. A previous study showed that CDGSH iron sulfur domain 2 (CISD2) can inhibit ferroptosis in cancer. Thus, we investigated the effects of CISD2 on ferroptosis and the mechanisms underlying its neuroprotective role in mice after ICH. CISD2 expression markedly increased after ICH. CISD2 over‐expression significantly decreased the number of Fluoro‐Jade C‐positive neurons and alleviated brain edema and neurobehavioral deficits at 24 h after ICH. In addition, CISD2 over‐expression up‐regulated the expression of p‐AKT, p‐mTOR, ferritin heavy chain 1, glutathione peroxidase 4, ferroportin, glutathione, and glutathione peroxidase activity, which are markers of ferroptosis. Additionally, CISD2 over‐expression down‐regulated the levels of malonaldehyde, iron content, acyl‐CoA synthetase long‐chain family member 4, transferrin receptor 1, and cyclooxygenase‐2 at 24 h after ICH. It also alleviated mitochondrial shrinkage and decreased the density of the mitochondrial membrane. Furthermore, CISD2 over‐expression increased the number of GPX4‐positive neurons following ICH induction. Conversely, knockdown of CISD2 aggravated neurobehavioral deficits, brain edema, and neuronal ferroptosis. Mechanistically, MK2206, an AKT inhibitor, suppressed p‐AKT and p‐mTOR and reversed the effects of CISD2 over‐expression on markers of neuronal ferroptosis and acute neurological outcome. Taken together, CISD2 over‐expression alleviated neuronal ferroptosis and improved neurological performance, which may be mediated through the AKT/mTOR pathway after ICH. Thus, CISD2 may be a potential target to mitigate brain injury via the anti‐ferroptosis effect after ICH. [ABSTRACT FROM AUTHOR]

The strong thermal effect is an important factor that hinders the application of nanosecond laser in the fabrication of uniform laser-induced periodic surface structures (LIPSS), though it offers the advantages of low cost and high efficiency. In this study, we show that regular microstructures consisting of LIPSS ribbons can be generated on chromium (Cr) metal via the two-beam interference scanning (TBIS) of a 1064-nm nanosecond laser, whereas LIPSS induced by the single-beam scanning (SBS) of the same laser has poor regularity due to excessive heat accumulation. Compared with SBS, TBIS is beneficial to minimize the undesirable thermal effects in the processing via the periodic intensity modulation, thus to generate homogenous LIPSS on Cr—we propose that the periodic intensity modulation derived from two-beam interference would lead to higher peak intensity that would form desired structures with a smaller effective pulse number, localize the heat-affected zones to benefit the positive grating-coupling feedback, and constrain the randomness of material redeposition during the TBIS processing. The results demonstrate that TBIS of nanosecond laser may provide an alternative way to efficiently fabricate uniform structures on various materials. [ABSTRACT FROM AUTHOR]

Since there are several limitations in cancer treatment for traditional chemotherapy, such as side effects, poor prognosis and drug resistance, developing new combined therapy is urgently needed. In this work, a biocompatible, simple and tumor microenvironment-responsive nanotheranostics (PCN-Oxpt/PEG) was built to favor the chemotherapy/ferroptosis/immunomodulation synergism in cancer. This nanotheranostics is constructed by modifying oxaliplatin prodrug and PEG on Fe(III) − porphyrin metal-organic frameworks (PCN(Fe) MOFs). After intravenous injection, the cloak of PEG leads to long circulation, and the Fe(III)-porphyrin MOFs enables dual-model guidance with fluorescence (FL) and magnetic resonance imaging (MRI). Inside the tumor, the intracellular H 2 O 2 would be transferred into hydroxyl radicals (•OH) by iron ions released from MOFs, which could trigger the lethal ferroptosis to cancer cells. Meanwhile, oxaliplatin(II) transformed from the loaded oxaliplatin prodrug would result in the chemotherapy, as well as immunogenic cell death (ICD), and the prodrug strategy could also avoid the occurring of liver damage by the direct administration of oxaliplatin(II). It was noticed that the ferroptosis effect was enhanced by triple-assistance during the combined therapy, as followed: (1) glutathione (GSH) would be consumed in the process of oxaliplatin(II) generation from oxaliplatin prodrug; (2) the increased CD8+ T cells induced by ICD were able to produce interferon-γ (IFN-γ), which could inhibit the transport of cystine by tumor cells, and impair the activation of glutathione peroxidase 4 (GPX4); (3) the amount of H 2 O 2 could be increased by the internalized oxaliplatin and thus further promote the Fenton reaction and ferroptosis. Both in vivo and in vitro results revealed that tumor growing was significantly inhibited by PCN-Oxpt/PEG, taken together, the concomitant of oxaliplatin-mediated chemotherapy and ICD with triple-enhanced ferroptosis offer great prospect in the clinical treatment of cancer. [Display omitted] • A novel nanoplatform (PCN-Oxpt/PEG) was designed for eliminating tumor with combined therapy. • The designed nanoplatform enables dual-model imaging (FL and MRI) to guide antitumor therapy. • Immunosuppressive tumor micro-environment could be remodeled by PCN-Oxpt/PEG, which would enhance ferroptosis efficiently. [ABSTRACT FROM AUTHOR]

• A SLM-assisted ns-laser processing technique is proposed for fabricating large-area, uniform, and well-arranged periodic structures on Cr films. • 2. For 1000-nm thick Cr films, the processed surface exhibits hybrid periodic microstructures comprised by modulated grating (MG) and laser induced periodic surface structures (LIPSS), that is, MG-LIPSS, which displays vivid anisotropic structural colors. • 3. For 200-nm thick Cr films, the processed hybrid structures are a combination of MG and cracks, that is, MGC, which can be utilized as a transmission grating with diffraction effects. An effective technique for preparing different hybrid periodic structures on chromium (Cr) films of different thicknesses using a 1064-nm nanosecond laser assisted by spatial light modulator (SLM) is proposed. For 1000-nm Cr films, by combining periodic modulated grating (MG) patterned by SLM with laser-induced periodic surface structures (LIPSS), regular dual-scale MG-LIPSS can be fabricated, with the morphological characteristics controlled by laser fluence, effective pulse number, and MG period. Due to diffraction effects of MG and LIPSS, MG-LIPSS patterned surfaces exhibit vivid anisotropic structural colors. In contract to MG-LIPSS, complex periodic structures consisting of MG and cracks (MGC) are fabricated on 200-nm Cr films due to the more significant thermal stress of a thinner film. Although the cracks of MGC distributed randomly, MGC show a long-range order characteristic with a certain transmittance, which can be utilized as a transmission grating with diffraction effects. These results demonstrate that optical field modulated laser machining based on SLM offers an efficient, cost-effective, and controllable method for fabricating large-area periodic structures on Cr films. Moreover, variations in film thickness can be employed to explore hybrid microstructures with specific properties, and thus utilized in diverse applications, such as optical components and anti-counterfeiting measures. [ABSTRACT FROM AUTHOR]

Supramolecular electronics provide opportunities to integrate molecular building blocks into electronic circuits, and investigations of the mechanical properties of the non‐covalent interactions are necessary to understand the role of the assembly configuration in the electronic coupling among different assembly blocks. However, the mechanical characterization of supramolecular interactions remains experimentally challenging. We investigated the strain distribution of the supramolecular interactions through a series of single‐stacking junctions. The alpha values exhibit a clear odd‐even effect versus the numbers of thiophene rings. The theoretical calculations demonstrated that a larger rotational barrier of the single‐stacking junctions with an even number of thiophene rings leads to limited torsional freedom and thus a smaller strain distribution. These results provide new insights into the control of supramolecular interactions by the design of the basic molecular building blocks. [ABSTRACT FROM AUTHOR]

Supramolecular electronics provide opportunities to integrate molecular building blocks into electronic circuits, and investigations of the mechanical properties of the non‐covalent interactions are necessary to understand the role of the assembly configuration in the electronic coupling among different assembly blocks. However, the mechanical characterization of supramolecular interactions remains experimentally challenging. We investigated the strain distribution of the supramolecular interactions through a series of single‐stacking junctions. The alpha values exhibit a clear odd‐even effect versus the numbers of thiophene rings. The theoretical calculations demonstrated that a larger rotational barrier of the single‐stacking junctions with an even number of thiophene rings leads to limited torsional freedom and thus a smaller strain distribution. These results provide new insights into the control of supramolecular interactions by the design of the basic molecular building blocks. [ABSTRACT FROM AUTHOR]

Bentonite colloids play an important role in the migration of radionuclides, while little is known about the difference of bentonite colloids generated at different temperature. In this research, the properties, includ surface charge, average size, sorption ability to uranium, migration ability with uranium, of bentonite colloids generated at different temperatures(20 °C, 45 °C and70 °C) are investigated. The results indicate that the higher the temperature, the smaller the average size of the colloids (from 213 nm at 20°C to 186 nm at 70°C). Besides, less content of montmorillonite is found in colloids generated at higher temperature (from 93 % at 20°C to 82 % at 70°C). To further investigate the difference of colloids generated at different temperatures, sorption and migration experiments of bentonite colloids and uranium(Ⅵ) are conducted. The result indicates that colloids generated at high temperature has high sorption ability to uranium, but with the increase of ionic strength, the sorption decreases, and more decrease is found at colloids generated at high temperature. In the system containing more than 3.5 mM NaCl, the sorption percentage of uranium onto the colloids generated at different temperatures are the same, indicating that uranium sorption onto the colloids is governed by inner-sphere and outer sphere complex, and the part of uranium sorption onto the colloids by inner sphere complex are almost the same. Migration experiments showed that uranium sorption onto the crushed granite is governed by inner-sphere complex. Bentonite colloids favored the migration of uranium, and Bentonite colloids generated at different temperatures had little difference on uranium migration at lower ionic strength. With the increase of ionic strength, the migration of bentonite colloids is hindered, leading to the decreased uranium migration. Based on the sorption mechanism, it is suggested that the uranium adsorbed onto the colloids by outer-sphere complex could desorb from the colloids and be adsorbed on the granite. The result could provide basis for modeling of bentonite colloids facilitated migration of uranium. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A universal, low-cost technique for fabricating absorbing-coating-assisted laser-induced periodic surface structures (ACA-LIPSS) on various types of solids is developed via nanosecond laser irradiation of ink coating on a solid surface. • An analytical model based on the standing-wave laser field is proposed to elucidate the different effective refractive indexes of ink layers on different substrates. • The ACA-LIPSS technique with the erasable characteristic can be employed to color both handmade artworks and digital scanning patterns. Brilliant iridescent structural color can be realized by micro-/nanostructuring of solid surfaces, but the preparation processes are usually complex and expensive. In the article, a universal, low-cost technique for fabricating absorbing-coating-assisted laser-induced periodic surface structures (ACA-LIPSS) on various types of solids including polymers, dielectrics, semiconductors, and metals, is developed via nanosecond laser irradiation of the ink (Solvent Black 7) coating on a solid surface. Because ink layers on different solid surfaces can be similarly coated manually and removed chemically, the ACA-LIPSS technique with the erasable characteristic can be employed to color both handmade artworks and digital scanning patterns on various solids universally. Moreover, an analytical model based on the standing-wave laser field is proposed to elucidate the different effective refractive indexes of ink layers on different substrates, and thus obtain the corresponding theoretical periods of ACA-LIPSS, which are in good agreement with the experimental ones with error <10%. In short, as a versatile surface micro-/nanostructuring approach, ACA-LIPSS successfully prepared on a variety of solids with high material universality, good durability, and rewritability show great application potentials in artwork creation, encryption, anti-counterfeiting, and deformation sensor. [ABSTRACT FROM AUTHOR]

Post-thrombotic syndrome (PTS) is a burdensome long-term complication of deep vein thrombosis (DVT). Recent studies have suggested that rivaroxaban may reduce PTS events compared to vitamin-K antagonists (VKAs). We, therefore, systematically reviewed available literature that compared rivaroxaban versus VKAs on the risk of PTS. We conducted a systematic review and meta-analysis using PubMed, EMBASE and Cochrane Library for all related studies from inception until March 2020. Two reviewers independently screened studies, extracted data, and appraised the quality of included studies. The primary outcome was overall risk of PTS. The secondary outcomes were risks of each PTS category (mild, moderate, severe) and venous ulcer. Seven comparative studies, comprising 2364 participants, qualified for this meta-analysis. The use of rivaroxaban for DVT treatment was associated with a lower risk of PTS compared with conventional VKAs [pooled unadjusted odds ratio (OR): 0.53, 95%CI: 0.43–0.65, P < 0.00001]. This effect was maintained after adjustment of potential confounders (pooled adjusted OR: 0.44, 95%CI: 0.35–0.56, P < 0.00001). Furthermore, rivaroxaban therapy was found to be associated with reduced risk of mild PTS (OR: 0.64, 95%CI: 0.50–0.82, P = 0.0005), moderate PTS (OR: 0.64, 95%CI: 0.45–0.91, P = 0.01), and severe PTS (OR: 0.52, 95%CI: 0.33–0.82, P = 0.005). There was also a similar trend towards reduced risk for venous ulcer, albeit not statistically significant (OR: 0.41, 95%CI: 0.15–1.08, P = 0.07). In comparison to VKAs, the use of rivaroxaban for DVT treatment has the potential to reduce PTS events. However, well-designed studies with larger sample sizes are needed to corroborate these findings. • The risk of PTS after DVT treated with rivaroxaban versus VKAs was systematically analyzed. • Compared with VKAs, rivaroxaban is associated with 47% reduced risk of PTS. • The reduced risk is observed in each of the three PTS categories, i.e. mild, moderate and severe. • Well-designed studies with larger sample sizes are needed to corroborate these findings. [ABSTRACT FROM AUTHOR]

To overcome the acquired resistance and the significant side-effects of the reported drugs, four new ruthenium(II) complexes with alkynyl (Ru1, Ru2, Ru3, Ru4) were designed and synthesized. Ru1, Ru2, Ru3 and Ru4 were characterized by ESI-MS, 1H NMR, 1H–1H COSY NMR and elemental analysis. Compared with Ru2, Ru3, Ru4 and cisplatin, the anti-tumor experiments in vitro and vivo confirmed that Ru1 could most effectively inhibit tumor growth. In the experiments of safety evaluation in vivo, Ru1 could avoid any detectable side-effects compared with cisplatin. DNA binding experiments and cell cycle experiments showed that Ru1 exhibited the strongest DNA binding ability and interfered with the cell cycle by inserting DNA to inhibit tumor growth. The study demonstrated that Ru1 had the potential to be an exciting new drug candidate for glioblastoma treatment. [ABSTRACT FROM AUTHOR]

• Developed method to fabricate dual-scale hybrid periodic structures on chromium. • Regular dual-scale periodic microstructures combining DILP and LIPSS could be fabricated. • The patterned surface exhibited vivid anisotropic structural colors. • The proposed method has great potential for use in anti-counterfeiting applications. • Alternative method to fabricate large-area hybrid periodic structures on materials. An effective method for fabricating dual-scale hybrid periodic structures on chromium (Cr) metal was developed using a 1064-nm nanosecond laser. By combining direct laser interference patterning (DLIP) and laser-induced periodic surface structures (LIPSS)—assisted by scanning technology—regular dual-scale periodic microstructures composed of orthogonal LIPSS and DLIP could be fabricated. The impact of processing parameters—including the laser fluence, effective pulse number, and scanning interval—on the formation and evolution of the orthogonally overlapping structures was investigated in detail. Moreover, the growth mechanism of the mixed structures on a chromium (Cr) surface was examined considering the heat accumulation effect. Due to the diffraction effects of DLIP and LIPSS, the patterned surface exhibited vivid anisotropic structural colors, showing potential for use in anti-counterfeiting applications. The results showed that ns-DLIP scanning techniques combined with LIPSS could provide an alternative route for fabricating large-area hybrid periodic structures on various materials. [ABSTRACT FROM AUTHOR]

Supramolecular electronics provide opportunities to integrate molecular building blocks into electronic circuits, and investigations of the mechanical properties of the non‐covalent interactions are necessary to understand the role of the assembly configuration in the electronic coupling among different assembly blocks. However, the mechanical characterization of supramolecular interactions remains experimentally challenging. We investigated the strain distribution of the supramolecular interactions through a series of single‐stacking junctions. The alpha values exhibit a clear odd‐even effect versus the numbers of thiophene rings. The theoretical calculations demonstrated that a larger rotational barrier of the single‐stacking junctions with an even number of thiophene rings leads to limited torsional freedom and thus a smaller strain distribution. These results provide new insights into the control of supramolecular interactions by the design of the basic molecular building blocks. [ABSTRACT FROM AUTHOR]

The emerging event cameras are bio-inspired sensors that can output pixel-level brightness changes at extremely high rates, and event-based visual-inertial odometry (VIO) is widely studied and used in autonomous robots. In this paper, we propose an event-based stereo VIO system, namely ESVIO. Firstly, we present a novel direct event-based VIO method, which fuses events' depth, Time-Surface images, and pre-integrated inertial measurement to estimate the camera motion and inertial measurement unit (IMU) biases in a sliding window non-linear optimization framework, effectively improving the state estimation accuracy and robustness. Secondly, we design an event-inertia semi-joint initialization method, through two steps of event-only initialization and event-inertia initial optimization, to rapidly and accurately solve the initialization parameters of the VIO system, thereby further improving the state estimation accuracy. Based on these two methods, we implement the ESVIO system and evaluate the effectiveness and robustness of ESVIO on various public datasets. The experimental results show that ESVIO achieves good performance in both accuracy and robustness when compared with other state-of-the-art event-based VIO and stereo visual odometry (VO) systems, and, at the same time, with no compromise to real-time performance. [ABSTRACT FROM AUTHOR]

Although the survival rate of hematological malignancies (HM) has increased in recent years, the unnecessary adverse effect to the body is usually generated by the traditional chemotherapy for HM due to the lack of specificity to tumor tissue. Nanodrug delivery systems have exhibited unique advantages in targetability, stability and reducing toxicity, attracting wide concern, which is expected to be the prevalent alternative for the treatment of HM. In this review, we systemically introduced the current therapeutic strategies and the categories of HM. Subsequently, five key factors including circulation, targeting, penetration, internalization and release involving in tailoring nanoparticles were demonstrated, followed by the introduction of the development of nanodrug delivery—traditional synthetic nanomaterilas, biomimetic cell membrane coating nanomaterials, cell-based nanomaterials as well as immunotherapy combined with nanodrug. Afterwards, the recent advances of nanodrug delivery system for the treatment of HM were introduced. Moreover, the challenge and prospect of nanodrug delivery system in treating HM were discussed. The promising drug delivery system will provide new therapeutic avenues for the treatment of HM. [ABSTRACT FROM AUTHOR]

Although the survival rate of hematological malignancies (HM) has increased in recent years, the unnecessary adverse effect to the body is usually generated by the traditional chemotherapy for HM due to the lack of specificity to tumor tissue. Nanodrug delivery systems have exhibited unique advantages in targetability, stability and reducing toxicity, attracting wide concern, which is expected to be the prevalent alternative for the treatment of HM. In this review, we systemically introduced the current therapeutic strategies and the categories of HM. Subsequently, five key factors including circulation, targeting, penetration, internalization and release involving in tailoring nanoparticles were demonstrated, followed by the introduction of the development of nanodrug delivery—traditional synthetic nanomaterilas, biomimetic cell membrane coating nanomaterials, cell-based nanomaterials as well as immunotherapy combined with nanodrug. Afterwards, the recent advances of nanodrug delivery system for the treatment of HM were introduced. Moreover, the challenge and prospect of nanodrug delivery system in treating HM were discussed. The promising drug delivery system will provide new therapeutic avenues for the treatment of HM. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of statins on risk of recurrent venous thromboembolism (VTE) was systematically analyzed. • Statins were associated with lower risks of recurrent VTE and its two forms, i.e. DVT and PE. • Statins were associated with a lower risk of mortality among patients with VTE. • Randomized clinical trials are warranted to corroborated these findings. Recent studies have suggested that statins may be associated with a lower risk of recurrent venous thromboembolism (VTE). We systematically searched PubMed, Web of Science and Cochrane Library from inception until May 2020 to identify any eligible studies that reported the association between statin use and the risk of recurrent VTE, and conducted a comprehensive systematic review and meta-analysis (PROSPERO registration number: CRD42020190169) on this matter. A total of 14 observational studies were included for qualitative review and 12 of them qualified for meta-analyses. The main meta-analysis found that statin use was associated with a lower risk of disease recurrence among patients with VTE (pooled adjusted HR: 0.76, 95% CI: 0.69−0.83), which was robust in sensitivity analyses and free of significant publication bias. Additionally, such association was present when restricting to periods after anticoagulation withdrawal (pooled adjusted HR: 0.78, 95% CI: 0.70−0.88) and when separately analyzing recurrent deep vein thrombosis (pooled adjusted HR: 0.71, 95% CI: 0.62−0.81) and recurrent pulmonary embolism (pooled adjusted HR: 0.80, 95% CI: 0.66−0.97; P = 0.027). Furthermore, statin use in patients with VTE was also found to be associated with a lower risk of all-cause mortality (adjusted HR: 0.65, 95% CI: 0.56−0.77), and possibly an even lower risk of bleeding (adjusted HR: 0.88, 95% CI: 0.73–1.07), albeit not statistically significant. Statins have the potential to reduce recurrent events among patient with VTE. Randomized clinical trials to better explore the effect of statins in secondary prevention of VTE are warranted. [ABSTRACT FROM AUTHOR]

Visual–inertial odometry (VIO) is widely studied and used in autonomous robots. This article proposes a novel tightly coupled monocular VIO system based on point-line constraints (PLC-VIO). In the front end, PLC-VIO presents a line segment extraction and merging algorithm based on the EDLines method and achieves real-time feature tracking based on the geometric constraints between feature points and lines. In the back end, PLC-VIO reconstructs new 3-D landmarks of feature lines through points on the line and optimizes the states by minimizing a cost function that combines the preintegrated inertial measurement unit (IMU) error term together with the point and line reprojection error terms in a sliding window optimization framework. A loop closure module is also integrated, which enables relocalization and drift elimination. The corresponding experimental evaluations are conducted using public datasets to validate the effectiveness and robustness of the proposed system, and the results show that PLC-VIO can achieve good performance when compared with other state-of-the-art systems and, at the same time, with no compromise to real-time performance. Note to Practitioners—Visual–inertial odometry (VIO) can estimate the states of the rigid body (including position, attitude, and velocity) that is widely used in robotic navigation, autonomous driving, virtual reality (VR), and augmented reality (AR). Aiming at the problem of estimating the states of autonomous robots in the GPS-denied environment, this article proposes a novel VIO system based on the point-line constraints (PLC-VIO). PLC-VIO can not only achieve accurate pose estimation for robots due to the introduction of the line features but also make no concession to real-time performance. Furthermore, PLC-VIO can also enrich the texture features of the environment during the 3-D mapping construction. The corresponding experiments are implemented in public datasets to evaluate the effectiveness, efficiency, and robustness of the proposed system. We believe that PLC-VIO can be widely used in robotic navigation and AR/VR fields to provide accurate position and environment information in real time. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Charge transport characterization of single‐molecule junctions is essential for the fundamental research of single‐molecule physical chemistry and the development towards single‐molecule electronic devices and circuits. Among the single‐molecule conductance characterization techniques, the single‐molecule break junction technique is widely used in tens of worldwide research laboratories which can generate a large amount of experimental data from thousands of individual measurement cycles. However, data interpretation is a challenging task for researchers with different research backgrounds, and the different data analysis approaches sometimes lead to the misunderstanding of the measurement data and even reproducibility issues of the measurement. It is thus a necessity to develop a user‐friendly all‐in‐one data analysis tool that automatizes the basic data analysis in a standard and widely accepted way. In this work, we present the XMe Code (Xiamen Molecular Electronics Code), an intelligent all‐in‐one data analysis tool for the comprehensive analysis of single‐molecule break junction data. XMe code provides end‐to‐end data analysis that takes in the original experimental data and returns electronic characteristics and even charge transport mechanisms. We believe that XMe Code will promote the transparency of the data analysis in single‐molecule electronics and the collaborations among scientists with different research backgrounds. [ABSTRACT FROM AUTHOR]

Human bone marrow-derived mesenchymal stem cells (hBMSCs) are promising candidates for stem cell therapy in clinical trials. Applications of hBMSCs in clinical therapy are limited by cellular senescence due to long-term ex vivo expansion. Metformin, an oral hypoglycemic drug for type 2 diabetes, has been shown to have antiaging effects. However, the mechanisms of metformin in antiaging treatment remain controversial. Here, we used D-galactose (D-gal) to establish an appropriate model of senescent hBMSCs to explore the antiaging effects of metformin. Following metformin treatment with a low concentration range, senescence phenotypes induced by D-gal significantly changed, including generation of reactive oxygen species (ROS), loss of mitochondrial membrane potential (MMP), and cell cycle arrest. In contrast, no apparent change was found in unsenescent hBMSCs. Furthermore, the results show that activation of 5 ′ AMP-activated protein kinase (AMPK) by metformin enhances cell autophagy in senescent hBMSCs. These findings suggest that metformin exerts antiaging function within the low concentration range by enhancing autophagy and exhibits potential benefits for clinical stem cell therapy by ameliorating the ex vivo replicative senescence of hBMSCs. [ABSTRACT FROM AUTHOR]

The therapeutic application of chemodynamic therapy (CDT) is severely limited by the insufficient intracellular H 2 O 2 and acidity in tumor. Herein, an acid-sensitive nanoplatform (ZIF67-ICG/TAM@GOx) to promote H 2 O 2 and acidity enhancement through intracellular cyclic amplification for enhanced CDT is rationally designed. Notably, the acidic conditions of the tumor microenvironment (TME) can turn on the switch of the nanoplatform, setting free the loaded tamoxifen (TAM) and indocyanine green (ICG). The mitochondrial respiration inhibitor TAM and the superoxide dismutase-mimicking ZIF67 synergistically lead to an increase in the content of O 2 and H 2 O 2 , accelerating the depletion of β- d -glucose by GOx to generate gluconate and H 2 O 2. The gluconate in turn boosts the acidity to facilitate the collapse of nanoparticles, further significantly promoting the accumulation of intracellular H 2 O 2 through a positive circulation. Consequently, the amplificated endogenous H 2 O 2 is catalyzed by Co2+ to liberate hydroxyl radicals (•OH). Besides, ICG-mediated photothermal therapy (PTT) and GOx-induced starvation therapy along with CDT realize the synergistic cancer treatment. Importantly, in vitro and in vivo experiments verified that the nanoplatform performed superior specificity and excellent therapeutic responses. The smart nanoplatform overcomes H 2 O 2 and acidity deficiency simultaneously for intensive CDT, providing new prospects for the development of biocompatible cancer synergistic therapy strategies. In the tumor microenvironment, the released TAM, GOx and ZIF67 synergistically lead to a positive circulation for self-amplified CDT, cooperating with PTT and starvation to realize the synergistic cancer treatment. [Display omitted] • An acidic sensitive nanoplatform (ZIF67-ICG/TAM@GOx) is constructed for specific tumor therapy. • The combination of TAM, ZIF67 and GOx enabled positive circulation to accumulate H 2 O 2 and acidity for boosting CDT. • The disruption of H 2 O 2 homeostasis made the approach of "expanding source and cost-saving" for the increase of H 2 O 2. • The self-amplified CDT along with PTT, GOx-induced starvation realized a novel synergistic cancer therapy strategy. [ABSTRACT FROM AUTHOR]

As an iron dependent regulatory cell death process driven by excessive lipid peroxides (LPO), ferroptosis is recognized as a powerful weapon for pancreatic cancer (PC) therapy. However, the tumor microenvironment (TME) with hypoxia and elevated glutathione (GSH) expression not only inhibits LPO production, but also induces glutathione peroxidase 4 (GPX4) mediated LPO clearance, which greatly compromise the therapeutic outcomes of ferroptosis. To address these issues, herein, a novel triple-enhanced ferroptosis amplifier (denoted as Zal@HM-PTBC) is rationally designed. After intravenous injection, the overexpressed H 2 O 2 /GSH in TME induces the collapse of Zal@HM-PTBC and triggers the production of oxygen and reactive oxygen species (ROS), which synergistically amplify the degree of lipid peroxidation (broaden sources). Concurrently, GSH consumption because of the degradation of the hollow manganese dioxide (HM) significantly weakens the activity of GPX4, resulting in a decrease in LPO clearance (reduce expenditure). Moreover, the loading and site-directed release of zalcitabine further promotes autophagy-dependent LPO accumulation (enhance effectiveness). Both in vitro and in vivo results validated that the ferroptosis amplifier demonstrated superior specificity and favorable therapeutic responses. Overall, this triple-enhanced LPO accumulation strategy demonstrates the ability to facilitate the efficacy of ferroptosis, injecting vigorous vitality into the treatment of PC. [Display omitted] • Zal@HM-PTBC was designed to facilitate ferroptosis by triple-enhanced LPO accumulation strategy. • TME induced the collapse of Zal@HM-PTBC and triggered the production of O 2 /ROS , which synergistically amplify LPO level. • The degradation of Zal@HM-PTBC consumed GSH in TME and attenuated "detoxification effect" on LPO by inactivating of GPX4. • The release of zalcitabine effectively led to autophagy dependent LPO accumulation. [ABSTRACT FROM AUTHOR]

Germinal matrix hemorrhage (GMH) is a devasting neurological disease in premature newborns. After GMH, brain iron overload associated with hemoglobin degradation contributed to oxidative stress, causing disruption of the already vulnerable blood-brain barrier (BBB). Mitochondrial ferritin (FTMT), a novel mitochondrial outer membrane protein, is crucial in maintaining cellular iron homeostasis. We aimed to investigate the effect of FTMT upregulation on oxidative stress and BBB disruption associated with brain iron overload in rats. A total of 222 Sprague-Dawley neonatal rat pups (7 days old) were used to establish a collagenase-induced GMH model and an iron-overload model of intracerebral FeCl 2 injection. Deferiprone was administered via gastric lavage 1 h after GMH and given daily until euthanasia. FTMT CRISPR Knockout and adenovirus (Ad)-FTMT were administered intracerebroventricularly 48 h before GMH and FeCl 2 injection, respectively. Neurobehavioral tests, immunofluorescence, Western blot, Malondialdehyde measurement, and brain water content were performed to evaluate neurobehavior deficits, oxidative stress, and BBB disruption, respectively. The results demonstrated that brain expressions of iron exporter Ferroportin (FPN) and antioxidant glutathione peroxidase 4 (GPX4) as well as BBB tight junction proteins including Claudin-5 and Zona Occulta (ZO)-1 were found to be decreased at 72 h after GMH. FTMT agonist Deferiprone attenuated oxidative stress and preserved BBB tight junction proteins after GMH. These effects were partially reversed by FTMT CRISPR Knockout. Iron overload by FeCl 2 injection resulted in oxidative stress and BBB disruption, which were improved by Ad-FTMT mediated FTMT overexpression. Collectively, FTMT upregulation is neuroprotective against brain injury associated with iron overload. Deferiprone reduced oxidative stress and BBB disruption by maintaining cellular iron homeostasis partially by the upregulating of FTMT after GMH. Deferiprone may be an effective treatment for patients with GMH. [Display omitted] • FTMT agonism Deferiprone reduced oxidative stress and BBB disruption after GMH. • FTMT upregulation improved neurobehavior deficits induced by iron overload. • FTMT upregulation attenuated oxidative stress and BBB disruption induced by iron overload. • FTMT upregulation decreased brain injury by maintaining cellular iron homeostasis. [ABSTRACT FROM AUTHOR]

Background: Chemodynamic therapy (CDT), employing Fenton or Fenton-like catalysts to convert hydrogen peroxide (H2O2) into toxic hydroxyl radicals (·OH) to kill cancer cells, holds great promise in tumor therapy due to its high selectivity. However, the therapeutic effect is significantly limited by insufficient intracellular H2O2 level in tumor cells. Fortunately, β-Lapachone (Lapa) that can exert H2O2-supplementing functionality under the catalysis of nicotinamide adenine dinucleotide (phosphate) NAD(P)H: quinone oxidoreductase-1 (NQO1) enzyme offers a new idea to solve this problem. However, extensive DNA damage caused by high levels of reactive oxygen species can trigger the "hyperactivation" of poly(ADP-ribose) polymerase (PARP), which results in the severe interruption of H2O2 supply and further the reduced efficacy of CDT. Herein, we report a self-amplified nanocatalytic system (ZIF67/Ola/Lapa) to co-deliver the PARP inhibitor Olaparib (Ola) and NQO1-bioactivatable drug Lapa for sustainable H2O2 production and augmented CDT ("1 + 1 + 1 > 3"). Results: The effective inhibition of PARP by Ola can synergize Lapa to enhance H2O2 formation due to the continuous NQO1 redox cycling. In turn, the high levels of H2O2 further react with Co2+ to produce the highly toxic ·OH by Fenton-like reaction, dramatically improving CDT. Both in vitro and in vivo studies demonstrate the excellent antitumor activity of ZIF67/Ola/Lapa in NQO1 overexpressed MDA-MB-231 tumor cells. Importantly, the nanocomposite presents minimal systemic toxicity in normal tissues due to the low NQO1 expression. Conclusions: This design of nanocatalytic system offers a new paradigm for combing PARP inhibitor, NQO1-bioactivatable drug and Fenton-reagents to obtain sustained H2O2 generation for tumor-specific self-amplified CDT. [ABSTRACT FROM AUTHOR]

Background: Lactose malabsorption occurs in around 68% of the world's population, causing lactose intolerance (LI) symptoms, such as abdominal pain, bloating, and diarrhea. To alleviate LI, previous studies have mainly focused on strengthening intestinal β-galactosidase activity while neglecting the inconspicuous drop in the colon pH caused by the fermentation of non-hydrolyzed lactose by the gut microbes. A drop in colon pH will reduce the intestinal β-galactosidase activity and influence intestinal homeostasis. Results: Here, we synthesized a tri-stable-switch circuit equipped with high β-galactosidase activity and pH rescue ability. This circuit can switch in functionality between the expression of β-galactosidase and expression of L-lactate dehydrogenase in response to an intestinal lactose signal and intestinal pH signal, respectively. We confirmed that the circuit functionality was efficient in bacterial cultures at a range of pH levels, and in preventing a drop in pH and β-galactosidase activity after lactose administration to mice. An impact of the circuit on gut microbiota composition was also indicated. Conclusions: Due to its ability to flexibly adapt to environmental variation, in particular to stabilize colon pH and maintain β-galactosidase activity after lactose influx, the tri-stable-switch circuit can serve as a promising prototype for the relief of lactose intolerance. [ABSTRACT FROM AUTHOR]

Herein, a multi-functional nanoplatform (PDA-DTC/Cu–MnO2) was established, which has been employed for MR imaging-guided multi-therapy (CDT, PTT and chemotherapy) for cancer treatment. The in vitro and in vivo results confirmed that the biocompatible nanoplatform could significantly induce tumor cell death and inhibit tumor growth. [ABSTRACT FROM AUTHOR]

Background. Vascular adventitia contains progenitor cells and is shown to participate in vascular remolding. Progenitor cells are recruited into the venous thrombi in mice to promote neovascularization. We hypothesized that the adventitial progenitor cells of human great saphenous vein (HGSV-AdPC) enhance the resolution of venous thrombosis via neovascularization. Methods. Human great saphenous vein (HGSV) was harvested from the patients with great saphenous vein varicose and sectioned for immunohistochemistry, or minced for progenitor cell primary culture, or placed in sodium dodecyl sulfate solution for decellularization. Human venous thrombi were collected from patients with great saphenous vein varicose and superficial thrombophlebitis. Infrarenal abdominal aorta of New Zealand white rabbits was replaced with interposing decellularized vessel, and the patency of the grafts was confirmed by ultrasonic examination. Animal venous thrombi in the left infrarenal vena cava of mice were produced with Prolene suture ligation and ophthalmic force clipping of this portion. After HGSVs were digested by collagenase, the CD34+CD117+ HGSV-AdPC were isolated on FACS system, labelled with CM-Dil, and transplanted into the adventitia of infrarenal vena cava of nude mice. The percentage of thrombus organization area to the thrombus area was calculated as the organization rate. The thrombus cell, endothelial cells, and macrophages in the thrombi were counted in sections. Cell smears and frozen sections of human saphenous veins and venous thrombi were labeled with Sca1, CD34, CD117, Flk1, CD31, and F4/80 antibodies. The CD34+CD117+ HGSV-AdPC were cultured in endothelial growth medium with vascular endothelial growth factor (VEGF) to induce endothelial cell differentiation and analyzed with real time-PCR, Western blotting, and tube formation assays. Results. Immunohistochemical staining showed that the CD34+CD117+ cells were located within the adventitia of HGSVs, and many CD34+ and CD117+ cells have emerged in the human venous thrombi. The number of progenitor cells within the marginal area of 7 days mice thrombi was shown to be Sca1+ ≈21%, CD34+ ≈12%, CD117+ ≈9%, and Flk1+ ≈5%. Many CD34+adventitial progenitor cells have migrated into the decellularized vessels. FACS showed that the number of CD34+CD117+ HGSV-AdPC in primary cultured cells as 1.2 ± 0.07 %. After CD34+CD117+HGSV-AdPC were transplanted into the adventitia of nude mice vena cava with venous thrombi, the organization rate, nucleate cell count, endothelial cells, and macrophage cells of thrombi were shown to be significantly increased. The transplanted CD34+CD117+ HGSV-AdPC at the adventitia have crossed the vein wall, entered the venous thrombi, and differentiated into endothelial cells. The CD34+CD117+ HGSV-AdPC in the culture medium in the presence of VEGF-promoted gene and protein expression of endothelial cell markers in vitro and induced tube formation. Conclusions. HGSV-AdPC could cross the vein wall and migrate from the adventitia into the venous thrombi. Increased HGSV-AdPC in the adventitia has enhanced the resolution of venous thrombi via differentiating into endothelial cells of neovascularization. [ABSTRACT FROM AUTHOR]

Hot-core heavy reduction rolling (HHR2) is an innovative thermomechanical technology whereby steel castings are directly rolled and heavily reduced at the solidification endpoint. HHR2 can effectively eliminate shrinkage porosities without the risk of internal cracking, as the centre deformation temperature has avoided the solidification brittleness temperature range. However, the risk of surface cracks is especially concerning because the lower surface temperature is associated with increased brittleness as compared to the centre. In this study, the EH47 was selected as the research material, which was a crack-sensitive steel with microalloy element Nb. Finite element model (FEM) analysis was used to predict surface ductile fracturing during HHR2. Hot compression tests were performed on specially designed specimens to develop the ductile fracture criterion for the FEM simulation. Pilot plant trials of HHR2 were carried out to verify the accuracy of the FEM calculations. The FEM results revealed that the centreline of a steel casting lateral face was the position where a fracture was most likely to take place. Moreover, the cracking risk itself rises with an increase in the reduction ratio, and the critical reduction ratio was about 59 %. The investigation also revealed that the cracking risk reduced with an increase in the work roll diameter. [ABSTRACT FROM AUTHOR]

To explore solvent gating of single-molecule electrical conductance due to solvent-molecule interactions, charge transport through single-molecule junctions with different anchoring groups in various solvent environments was measured by using the mechanically controllable break junction technique. We found that the conductance of single-molecule junctions can be tuned by nearly an order of magnitude by varying the polarity of solvent. Furthermore, gating efficiency due to solvent–molecule interactions was found to be dependent on the choice of the anchor group. Theoretical calculations revealed that the polar solvent shifted the molecular-orbital energies, based on the coupling strength of the anchor groups. For weakly coupled molecular junctions, the polar solvent–molecule interaction was observed to reduce the energy gap between the molecular orbital and the Fermi level of the electrode and shifted the molecular orbitals. This resulted in a more significant gating effect than that of the strongly coupled molecules. This study suggested that solvent–molecule interaction can significantly affect the charge transport through single-molecule junctions. [ABSTRACT FROM AUTHOR]

Together with the more intuitive and commonly recognized conductance mechanisms of charge‐hopping and tunneling, quantum‐interference (QI) phenomena have been identified as important factors affecting charge transport through molecules. Consequently, establishing simple and flexible molecular‐design strategies to understand, control, and exploit QI in molecular junctions poses an exciting challenge. Here we demonstrate that destructive quantum interference (DQI) in meta‐substituted phenylene ethylene‐type oligomers (m‐OPE) can be tuned by changing the position and conformation of methoxy (OMe) substituents at the central phenylene ring. These substituents play the role of molecular‐scale taps, which can be switched on or off to control the current flow through a molecule. Our experimental results conclusively verify recently postulated magic‐ratio and orbital‐product rules, and highlight a novel chemical design strategy for tuning and gating DQI features to create single‐molecule devices with desirable electronic functions. [ABSTRACT FROM AUTHOR]

Together with the more intuitive and commonly recognized conductance mechanisms of charge‐hopping and tunneling, quantum‐interference (QI) phenomena have been identified as important factors affecting charge transport through molecules. Consequently, establishing simple and flexible molecular‐design strategies to understand, control, and exploit QI in molecular junctions poses an exciting challenge. Here we demonstrate that destructive quantum interference (DQI) in meta‐substituted phenylene ethylene‐type oligomers (m‐OPE) can be tuned by changing the position and conformation of methoxy (OMe) substituents at the central phenylene ring. These substituents play the role of molecular‐scale taps, which can be switched on or off to control the current flow through a molecule. Our experimental results conclusively verify recently postulated magic‐ratio and orbital‐product rules, and highlight a novel chemical design strategy for tuning and gating DQI features to create single‐molecule devices with desirable electronic functions. [ABSTRACT FROM AUTHOR]

As a type of nanomaterials with enzyme-mimetic catalytic properties, nanozymes have attracted wide concern in biological detection. H 2 O 2 was the characteristic product of diverse biological reactions, and the quantitative analysis for H 2 O 2 was an important way to detect disease biomarkers, such as acetylcholine, cholesterol, uric acid and glucose. Therefore, there is of great significance for developing a simple and sensitive nanozyme to detect H 2 O 2 and disease biomarkers by combining with corresponding enzyme. In this work, Fe-TCPP MOFs were successfully prepared by the coordination between iron ions and porphyrin ligands (TCPP). In addition, the peroxidase (POD) activity of Fe-TCPP was proved, in detail, Fe-TCPP could catalyze H 2 O 2 to produce ·OH. Herein, glucose oxidase (GOx) was chosen as the model to build cascade reaction by combining Fe-TCPP to detect glucose. The results indicated glucose could be detected by this cascade system selectively and sensitively, and the limit of detection of glucose was achieved to 0.12 μM. Furthermore, a portable hydrogel (Fe-TCPP@GEL) was further established, which encapsulated Fe-TCPP MOFs, GOx and TMB in one system. This functional hydrogel could be applied for colorimetric detection of glucose by coupling with a smartphone easily. Nanozyme of Fe-TCPP and corresponding hydrogel were constructed, and they were further developed to detect glucose. [Display omitted] • A simple and efficient nanozyme for the detection of glucose is reported. • A universal hydrogel system containing both natural enzymes and nanozymes is developed. • Fe-TCPP@GEL could carry out the quantitative analysis of glucose by coupling with a smartphone easily. [ABSTRACT FROM AUTHOR]

Photoresponsive molecular systems are essential for molecular optoelectronic devices, but most molecular building blocks are non‐photoresponsive. Employed here is a photoinduced proton transfer (PIPT) strategy to control charge transport through single‐molecule azulene junctions with visible light under ambient conditions, which leads to a reversible and controllable photoresponsive molecular device based on non‐photoresponsive molecules and a photoacid. Also demonstrated is the application of PIPT in two single‐molecule AND gate and OR gate devices with electrical signal as outputs. Out of the blue: By using a photoinduced proton‐transfer (PIPT) strategy, a non‐photoresponsive 1,3‐azulene derivative can be modulated in single‐molecule junctions by blue light, with conductance variation by almost one order of magnitude. This behavior can lead to potential applications in single‐molecule logic gate devices with electrical outputs. [ABSTRACT FROM AUTHOR]

Photoresponsive molecular systems are essential for molecular optoelectronic devices, but most molecular building blocks are non‐photoresponsive. Employed here is a photoinduced proton transfer (PIPT) strategy to control charge transport through single‐molecule azulene junctions with visible light under ambient conditions, which leads to a reversible and controllable photoresponsive molecular device based on non‐photoresponsive molecules and a photoacid. Also demonstrated is the application of PIPT in two single‐molecule AND gate and OR gate devices with electrical signal as outputs. [ABSTRACT FROM AUTHOR]

We studied the single-molecule conductance through an acid oxidant triggered phenothiazine (PTZ-) based radical junction using the mechanically controllable break junction technique. The electrical conductance of the radical state was enhanced by up to 200 times compared to the neutral state, with high stability lasting for at least two months and high junction formation probability at room-temperature. Theoretical studies revealed that the conductance increase is due to a significant decrease of the HOMO-LUMO gap and also the enhanced transmission close to the HOMO orbital when the radical forms. The large conductance enhancement induced by the formation of the stable PTZ radical molecule will lead to promising applications in single-molecule electronics and spintronics. [ABSTRACT FROM AUTHOR]

We studied the single-molecule conductance through an acid oxidant triggered phenothiazine (PTZ-) based radical junction using the mechanically controllable break junction technique. The electrical conductance of the radical state was enhanced by up to 200 times compared to the neutral state, with high stability lasting for at least two months and high junction formation probability at room-temperature. Theoretical studies revealed that the conductance increase is due to a significant decrease of the HOMO-LUMO gap and also the enhanced transmission close to the HOMO orbital when the radical forms. The large conductance enhancement induced by the formation of the stable PTZ radical molecule will lead to promising applications in single-molecule electronics and spintronics. [ABSTRACT FROM AUTHOR]

The cracks formed in the hot deformation are typical defects caused by plastic capacity limitations. For tested steels, the fracture behavior is associated with temperature, strain rate, and stress state. In this study, a highly crack-sensitive steel with Nb micro-alloying is selected as the research material to establish the fracture criterion considering the above factors comprehensively. First, compression and tension experiments are performed, and various specimen geometries are designed to produce different stress states in the tests at different temperatures and strain rates. Second, the critical stroke of these tests is extracted, and corresponding calculations are completed using the finite element method (FEM). The loading paths of stress states are independent of temperature and strain rate; however, they differ when distinct specimen shapes are considered in the tests. Third, a high–temperature Mohr–Coulomb criterion, which is applicable at elevated temperatures, is established by considering the effects of temperature, strain rate, and stress states on fracture. Finally, some examples of compressive and tensile tests are employed for verifying the formulated fracture criterion. By comparing the FEM and experimental results, it is found that the fracture criterion could accurately describe the fracture behavior during hot deformation with distinct stress paths. • Various stress states and stress paths are used in the tests for modeling at elevated temperatures. • In-situ observation of fracture based on CLSM. • A modified Mohr–Coulomb criterion is established by considering the influences of stress state, temperature, and strain rate. • Fracture analysis and model validation are accomplished based on the combined experimental and FEM results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Temperature and cooling time affect the generation of hollow silver nanoparticles. • Cavity formation in the silver nanoparticle occurs at temperatures of 2000 K to 3000 K. • A fast cooling time is essential for the formation of a complete cavity. • The physical mechanisms are pressure relaxation and uneven diffusion of Ag atoms. • Energy dissipation from an Ag particle to fused silica has a timescale of 20–30 ps. We used classical molecular dynamics with a two-temperature model to investigate the cavity-formation process of silver nanoparticles under ultrafast laser irradiation. We investigated two different scenarios. The first scenario involved a single silver nanoparticle and the second involved a silver nanosphere embedded in fused silica. For the former, simulation results indicated that the peak temperature and cooling time are two key factors affecting the formation of stable hollow nanostructures in silver nanoparticles. When the temperature was below 2000 K, there was no cavity formation in the particle. In contrast, when the temperature exceeded 3000 K, the silver nanoparticle exhibited an irregular structure, namely, that of a spherical shell with small perforations. The cooling time, which represents the duration for energy from a nanoparticle to dissipate into the surrounding matrix, is also crucial. The results revealed that a stable hollow nanostructure could only form when the cooling time was <180 ps. By analyzing the local pressure and root–mean–square displacement of the atoms, we observed that these two parameters were responsible for the formation of an inner cavity. In the second case, we demonstrated the dynamic transformation of a solid silver nanoparticle embedded in fused silica into a hollow nanostructure under ultrafast laser irradiation. The results from this case indicated the time range for dissipation of energy from a silver nanoparticle into the fused silica to be between 20 and 30 ps. [ABSTRACT FROM AUTHOR]