Exploring the mechanism of lung injury induced by lunar dust simulant in rats based on metabolomic analysis.

Inflammatory response and oxidative stress are considered to be important mechanisms of lung injury induced by lunar dust. However, the pulmonary toxicological mechanism remains unclear. In the present study, Wistar rats were exposed to CLDS-i 7 days/week, 4 h/day, for 4 weeks in the mouth and nose. Lung tissue samples were collected for histopathological analysis and ultra-performance liquid chromatography-mass spectrometry analysis. Enzyme activities and expression levels of key metabolic enzymes were detected by biochemical analysis and real-time PCR. The pathological features of lung tissue showed that CLDS-i caused congestion and inflammation in the lungs, and the lung structure was severely damaged. Metabolomics analysis showed that 141 metabolites were significantly changed in the lung tissue of the CLDS-i group compared with the control group. Combined with Kegg pathway analysis, it was found that the changes of amino acid metabolites were involved in these pathways, indicating that the simulated lunar dust exposure had the most obvious effect on amino acid metabolism in the lung tissue of rats. Real-time PCR analysis showed that the mRNA expression of six key enzymes related to amino acid metabolism was changed, and the enzyme activities of these key enzymes were also changed, which were consistent with the results of qPCR. These results suggest that changes in amino acid metabolism may be closely related to the pathogenesis of lung injury induced by lunar dust, and amino acid metabolism may be a potential biomarker of lung diseases related to lunar dust exposure.

Anticoagulation Therapy for Splanchnic Vein Thrombosis Associated With Acute Pancreatitis: A Systematic Review and Meta-Analysis.

Splanchnic vein thrombosis (SVT) is not rare in patients with acute pancreatitis. It remains unclear about whether anticoagulation should be given for acute pancreatitis-associated SVT. The PubMed, EMBASE, and Cochrane Library databases were searched. Rates of SVT recanalization, any bleeding, death, intestinal ischemia, portal cavernoma, and gastroesophageal varices were pooled and compared between patients with acute pancreatitis-associated SVT who received and did not receive therapeutic anticoagulation. Pooled rates and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated. Heterogeneity among studies was evaluated. Overall, 16 studies including 698 patients with acute pancreatitis-associated SVT were eligible. After therapeutic anticoagulation, the pooled rates of SVT recanalization, any bleeding, death, intestinal ischemia, portal cavernoma, and gastroesophageal varices were 44.3% (95%CI = 32.3%-56.6%), 10.7% (95%CI = 4.9%-18.5%), 13.3% (95%CI = 6.9%-21.4%), 16.8% (95%CI = 6.9%-29.9%), 21.2% (95%CI = 7.5%-39.5%), and 29.1% (95%CI = 16.1%-44.1%), respectively. Anticoagulation therapy significantly increased the rate of SVT recanalization (RR = 1.69; 95%CI = 1.29-2.19; P < .01), and marginally increased the risk of bleeding (RR = 1.98; 95%CI = 0.93-4.22; P = .07). The rates of death (RR = 1.42; 95%CI = 0.62-3.25; P = .40), intestinal ischemia (RR = 2.55; 95%CI = 0.23-28.16; P = .45), portal cavernoma (RR = 0.51; 95%CI = 0.21-1.22; P = .13), and gastroesophageal varices (RR = 0.71; 95%CI = 0.38-1.32; P = .28) were not significantly different between patients who received and did not receive anticoagulation therapy. Heterogeneity was statistically significant in the meta-analysis of intestinal ischemia, but not in those of SVT recanalization, any bleeding, death, portal cavernoma, or gastroesophageal varices. Anticoagulation may be effective for recanalization of acute pancreatitis-associated SVT, but cannot improve the survival. Randomized controlled trials are warranted to further investigate the clinical significance of anticoagulation therapy in such patients.

Improving Thermal Conductivity and Tribological Performance of Polyimide by Filling Cu, CNT, and Graphene.

The thermal conductivity, mechanical, and tribological properties of polyimide (PI) composites filled by copper (Cu), carbon nanotube (CNT), graphene nanosheet (GNS), or combination were investigated by molecular dynamics simulation (MD). The simulated results suggested that Cu can improve thermal stability and thermal conductivity, but it reduces mechanical properties and tribological properties. CNT and GNS significantly improved the thermal and tribological properties at low content, but they decreased the properties at high content. In this study, the modification mechanism, friction, and wear mechanism of different fillers on polyimide were revealed by observing the frictional interface evolution process from the atomic scale, extracting the atomic relative concentration, the temperature and velocity distribution at the friction interface, and other microscopic information.

The Response of Rocky Desertification to the Development of Road Networks in Karst Ecologically Fragile Areas.

Frequent cross-regional communication makes road networks increasingly dense and has generated prominent human interference, thus resulting in the destruction of the landscape's integrity and leading to changes in the functional processes of the habitat. In order to discuss the impacts of intense human activity brought by the road networks on the rocky desertification landscape and habitat quality in karst ecologically fragile areas, taking the road networks as the humans activity intensity factor, a quantitative analysis was conducted to analyze the impacts of road networks on the spatial evolution of the rocky desertification landscape and changes in regional habitat quality characteristics under different development modes in the study area based on a landscape pattern gradient method, spatial analysis, and INVEST model. The results showed that: (1) in the study area, due to the destruction of landscape integrity caused by the development of the road networks over the past 17 years, the landscape pattern of rocky desertification tended to be fragmented and complex, first showing an inclination for rapid fragmentation and then gradual recovery later. (2) The land-use intensity and degree of rocky desertification in the industrial areas and in the tourist areas of the study area have increased to varying degrees over the past 17 years, as is seen mainly via the expansion of construction land, cultivated land enclaves in the urban expansion areas, and new development areas. (3) Unders different regional models, the fragmentation of the rocky desertification landscape in the industrial areas was higher than that in the tourist areas, resulting in a significantly lower habitat quality and obvious degrees of degradation. The research findings provide the basis for further deepening our understanding how human activity intensity affects the evolution of the regional landscape, including the development of rocky desertification, the supply of services, and supporting habitat conservation in karst ecologically fragile areas.

Effect of Cu-Sn Addition on Corrosion Property of Pressureless Sintered Fe-Cu-Co Substrate Alloys.

Fe-Cu-Co prealloyed powder is used for bonding metal of diamond tools. In order to obtain diamond tools with good mechanical properties by pressureless sintering, it is necessary to add Cu-Sn sintering aids. The substrate also has high corrosion resistance requirements, which is conducive to the chemical erosion of diamond tools. This paper mainly studies the effects of Cu-Sn on the corrosion behavior of pressureless sintered Fe-Cu-Co substrate. The results show that the linear contraction rate and relative density of pressureless sintered Fe-Cu-Co alloy at 875 °C reach their peak when the Cu-Sn content is 8 wt.%, 15.13% and 97.5%, respectively. The substrate is mainly composed of α-Fe and Cu-rich phases, and selective corrosion occurs during electrochemical corrosion; namely, α-Fe grains are more prone to corrosion than Cu-rich grains to form porous corrosion surfaces. With the increase in Cu-Sn addition, the volume fraction of the Cu-rich phase increases, the corrosion current density and the passive current density gradually decrease, and the corrosion resistance of the alloy is improved. The amount and integrity of anodic passive film on the Fe-Cu-Co surface increases with the increase in Cu-Sn addition. The oxygen content of the anodic passivation film is lower than that of the active corrosion products of the α-Fe phase, thus reducing the oxygen concentration gradient and slowing down the corrosion. The addition of Cu-Sn is conducive to improving the corrosion resistance of Fe-Cu-Co alloy as the substrate of diamond tools.

Evolution of optical vortices in gradient media and curved spaces.

Light propagation in gradient media and curved spaces induce intriguing phenomena, such as focusing and self-imaging, thus delivering a wide range of applications. However, these systems are limited to excitations without orbital angular momentum, which may produce unforeseen results. Here, we demonstrate the reconstructions (or called imaging to some extent) of optical vortices (OVs) in two-dimensional (2D) gradient media and three-dimensional (3D) curved spaces. We present the evolution of OVs in two types of generalized Maxwell fisheye (GMFE) lenses from the perspective of geometrical and wave optics, and use coherent perfect absorbers (CPAs) to better recover the OVs in the converging position. Furthermore, we also demonstrate such phenomena in two types of 3D compact closed manifolds-sphere and spindle-which are also called geodesic lenses. Surprisingly, the results we obtained in 3D curved spaces can be seen as a strong verification of the Poincaré-Hopf theorem. Our work provides a new, to the best of our knowledge, platform to investigate the evolution of OVs on curved surfaces.

Efficacy and safety of thrombolytic therapy for portal venous system thrombosis: A systematic review and meta-analysis.

BACKGROUND AND AIMS: The role of thrombolytic therapy in patients with portal venous system thrombosis (PVST) remains ambiguous. This study aimed to systematically collect available evidence and evaluate the efficacy and safety of thrombolysis for PVST. METHODS: Eligible studies were searched via PubMed, EMBASE, and Cochrane Library databases. Among the cohort studies, meta-analyses were performed to assess the outcomes of PVST patients receiving thrombolysis. Pooled proportions were calculated. Among the case reports and case series, logistic regression analyses were performed to identify the risk factors for outcomes of PVST patients receiving thrombolysis. Odds ratios (ORs) were calculated. RESULTS: Among the 2134 papers initially identified, 29 cohort studies and 131 case reports or case series were included. Based on the cohort studies, the pooled rates of overall response to thrombolytic therapy, complete recanalization of PVST, bleeding events during thrombolysis, further bowel resection, thrombosis recurrence, and 30-day mortality were 93%, 58%, 18%, 3%, 1%, and 4%, respectively. Based on the case reports and case series, acute pancreatitis (OR = 0.084), history of liver transplantation (OR = 13.346), and interval between onset of symptoms and initiation of thrombolysis ≤14 days (OR = 3.105) were significantly associated with complete recanalization of PVST; acute pancreatitis (OR = 6.556) was significantly associated with further bowel resection; but no factors associated with the overall response to thrombolytic therapy, bleeding events during thrombolysis, thrombosis recurrence, and 30-day mortality were identified or could be calculated. CONCLUSION: Early initiation of thrombolysis should be effective for the treatment of PVST. But its benefits for PVST secondary to acute pancreatitis are weakened.

Ecological Quality Evolution and Its Driving Factors in Yunnan Karst Rocky Desertification Areas.

Rocky desertification is a key element affecting regional ecological quality. Rocky desertification in Southwest China directly affects the ecological security of the Yangtze River and Pearl River basins and also restricts regional economic and social development. In order to clarify the evolution laws and key influencing factors of ecological quality in Yunnan karst rocky desertification areas, a quantitative analysis based on the remote sensing-based ecological index (RSEI) model was conducted to explore the overall evolution characteristics and change laws of ecological quality in Yunnan karst rocky desertification areas in the past 30 years. The correlation between RSEI, rock outcrop rate (Fr), and driving factors was determined by redundancy analysis. The results showed the following: (1) RSEI in Yunnan karst rocky desertification areas generally showed a decreasing trend, with a fluctuation in the mid-term, followed by a tendency to recover. It fell into three stages: decline, trough, and recovery, with fitting coefficients of -0.121, -0.057, and 0.157, respectively. In contrast, Fr showed an opposite tendency, illustrating the inverse relationship between RSEI and Fr, and the rate of sequential succession was much faster than that of the reverse succession under human measures of intervention. (2) The mean value of RSEI of Yunnan karst rocky desertification areas was generally lower than that of the total Yunnan Province land areas and Yunnan non-karst rocky desertification areas, but the mean value of Fr was generally more than that of both the above-mentioned areas. In addition, the RSEI and Fr of Yunnan karst rocky desertification areas both showed lower stability values than those of both the above-mentioned areas. This generally suggested a low ecological quality and a high degree of desertification under a low stability in Yunnan karst rocky desertification areas. (3) The correlation of RSEI and Fr with driving factors followed the order of topographic factors, soil factors > water factors > anthropogenic factors. Anthropogenic factors were the driving force changing the state of rocky desertification, geological factors such as topography and soil to a larger extent determined the original macroscopic ecological relationship of rocky desertification, and water factors lay between the above two. The findings of this research will provide theoretical support and a basis for the improvement of ecological quality and comprehensive control of karst rocky desertification in Yunnan Province.

Observation of Topological p-Orbital Disclination States in Non-Euclidean Acoustic Metamaterials.

Disclinations-topological defects ubiquitously existing in various materials-can reveal the intrinsic band topology of the hosting material through the bulk-disclination correspondence. In low-dimensional materials and nanostructure such as graphene and fullerenes, disclinations yield curved surfaces and emergent non-Euclidean geometries that are crucial in understanding the properties of these materials. However, the bulk-disclination correspondence has never been studied in non-Euclidean geometry, nor in systems with p-orbital physics. Here, by creating p-orbital topological acoustic metamaterials with disclination-induced conic and hyperbolic surfaces, we demonstrate the rich emergent bound states arising from the interplay among the real-space geometry, the bulk band topology, and the p-orbital physics. This phenomenon is confirmed by clear experimental evidence that is consistent with theory and simulations. Our experiment paves the way toward topological phenomena in non-Euclidean geometries and will stimulate interesting research on, e.g., topological phenomena for electrons in nanomaterials with curved surfaces.

Improving the prediction of DNA-protein binding by integrating multi-scale dense convolutional network with fault-tolerant coding.

Accurate prediction of DNA-protein binding (DPB) is of great biological significance for studying the regulatory mechanism of gene expression. In recent years, with the rapid development of deep learning techniques, advanced deep neural networks have been introduced into the field and shown to significantly improve the prediction performance of DPB. However, these methods are primarily based on the DNA sequences measured by the ChIP-seq technology, failing to consider the possible partial variations of the motif sequences and errors of the sequencing technology itself. To address this, we propose a novel computational method, termed MSDenseNet, which combines a new fault-tolerant coding (FTC) scheme with the dense connectional deep neural networks. Three important factors can be attributed to the success of MSDenseNet: First, MSDenseNet utilizes a powerful feature representation approach, which transforms the raw DNA sequence into fusion coding using the fault-tolerant feature sequence; Second, in terms of network structure, MSDenseNet uses a multi-scale convolution within the dense layer and the multi-scale convolution preceding the dense block. This is shown to be able to significantly improve the network performance and accelerate the network convergence speed, and third, building upon the advanced deep neural network, MSDenseNet is capable of effectively mining the hidden complex relationship between the internal attributes of fusion sequence features to enhance the prediction of DPB. Benchmarking experiments on 690 ChIP-seq datasets show that MSDenseNet achieves an average AUC of 0.933 and outperforms the state-of-the-art method. The source code of MSDenseNet is available at https://github.com/csbio-njust-edu/msdensenet. The results show that MSDenseNet can effectively predict DPB. We anticipate that MSDenseNet will be exploited as a powerful tool to facilitate a more exhaustive understanding of DNA-binding proteins and help toward their functional characterization.

Colorectal cancer: Metabolic interactions reshape the tumor microenvironment.

Colorectal cancer (CRC) is one of the most common cancers worldwide, which ranks third in terms of incidence and the second leading cause of cancer-related mortality. Metabolic reprogramming within the tumor microenvironment (TME) has been proved intimately involved in the initiation and malignant progression of CRC. Signal messengers, including cytokines, metabolites, and exosomes among others, derived from cancer cells can be utilized by the surrounding cells within the TME to induce metabolic alteration and cancer-associated transformation. In turn, the cargos secreted from cancer-associate cells further provide the nutrition and energy supply for cancer cells, supporting their metabolic reprogramming to promote proliferation, migration, metastasis, and radiochemoresistance. In this review, we focus on the main cellular components in the TME: CAFs, TAMs, lymphocytes and neutrophils, and enumerate and integrate how the metabolic interactions between these components and cancer cells reshape TME to foster CRC malignancy.

Small Object Detection in Traffic Scenes Based on Attention Feature Fusion.

There are many small objects in traffic scenes, but due to their low resolution and limited information, their detection is still a challenge. Small object detection is very important for the understanding of traffic scene environments. To improve the detection accuracy of small objects in traffic scenes, we propose a small object detection method in traffic scenes based on attention feature fusion. First, a multi-scale channel attention block (MS-CAB) is designed, which uses local and global scales to aggregate the effective information of the feature maps. Based on this block, an attention feature fusion block (AFFB) is proposed, which can better integrate contextual information from different layers. Finally, the AFFB is used to replace the linear fusion module in the object detection network and obtain the final network structure. The experimental results show that, compared to the benchmark model YOLOv5s, this method has achieved a higher mean Average Precison (mAP) under the premise of ensuring real-time performance. It increases the mAP of all objects by 0.9 percentage points on the validation set of the traffic scene dataset BDD100K, and at the same time, increases the mAP of small objects by 3.5%.

Multiple drains in generalized Maxwell's fisheye lenses.

The subwavelength imaging phenomenon in Maxwell's fisheye lens with one drain has been reported previously. In this paper, we theoretically find that coherent perfect absorbers (CPAs) perform well in generalized Maxwell's fisheye (GMFE) lenses. Such CPAs are embedded inside the GMFE lenses to absorb the incoming coherent waves. They can be served as drains and dramatically improve the resolution of images in the GMFE lenses. In particular, they can be applied to realize the subwavelength imaging. We also study the multiple imaging characteristics of GMFE lenses with several CPAs in wave optics. Full-wave simulations were performed to verify the imaging functionalities.

Solution-Processable 2D Polymer/Graphene Oxide Heterostructure for Intrinsic Low-Current Memory Device.

Suppressing the operating current in resistive memory devices is an effective strategy to minimize their power consumption. Herein, we present an intrinsic low-current memory based on two-dimensional (2D) hybrid heterostructures consisting of partly reduced graphene oxide (p-rGO) and conjugated microporous polymer (CMP) with the merits of being solution-processed, large-scale, and well patterned. The device with the heterostructure of p-rGO/CMP sandwiched between highly reduced graphene oxide (h-rGO) and aluminum electrodes exhibited rewritable and nonvolatile memory behavior with an ultralow operating current (∼1 µA) and efficient power consumption (∼2.9 µW). Moreover, the on/off current ratio is over 103, and the retention time is up to 8 × 103 s, indicating the low misreading rate and high stability of data storage. So far, the value of power is about 10 times lower than those of the previous GO-based memories. The bilayer architecture provides a promising approach to construct intrinsic low-power resistive memory devices.

Multifunctional Polymer Memory via Bi-Interfacial Topography for Pressure Perception Recognition.

Emerging memory devices, that can provide programmable information recording with tunable resistive switching under external stimuli, hold great potential for applications in data storage, logic circuits, and artificial synapses. Realization of multifunctional manipulation within individual memory devices is particularly important in the More-than-Moore era, yet remains a challenge. Here, both rewritable and nonerasable memory are demonstrated in a single stimuli-responsive polymer diode, based on a nanohole-nanowrinkle bi-interfacial structure. Such synergic nanostructure is constructed from interfacing a nanowrinkled bottom graphene electrode and top polymer matrix with nanoholes; and it can be easily prepared by spin coating, which is a low-cost and high-yield production method. Furthermore, the resulting device, with ternary and low-power operation under varied external stimuli, can enable both reversible and irreversible biomimetic pressure recognition memories using a device-to-system framework. This work offers both a general guideline to fabricate multifunctional memory devices via interfacial nanostructure engineering and a smart information storage basis for future artificial intelligence.

Hierarchical Hollow-Pore Nanostructure Bilayer Heterojunction Comprising Conjugated Polymers for High-Performance Flash Memory.

We report the design and preparation of hierarchical hollow-pore nanostructure bilayer conjugated polymer films for high-performance resistive memory devices. By taking the merits of chemical and structural stabilities of a two-dimensional conjugated microporous polymer (2D CMP), a poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) film with a hollow surface was spin-coated onto 2D CMP nanofilm directly, constructing a bilayer heterojunction. A two-terminal diode with a configuration of indium tin oxide/2D CMP/hollow MEH-PPV/Al was fabricated by employing the prepared bilayer heterojunction. The device poses flash feature with a high on/off ratio (>105) and a long retention time (>3.0 × 104 s), which is higher than that of most of the reported conjugated polymers memories. Our work offers a general guideline to construct high on/off ratio polymer memories via hierarchical nanostructure engineering in memristive layer.

Electrostatically assembled carbon dots/boron nitride nanosheet hybrid nanostructures for thermal quenching-resistant white phosphors.

Carbon dots (C-dots) are promising and widely applied carbon fluorescent materials for next-generation white light-emitting diodes (WLEDs). However, nonnegligible thermal quenching issues induced by high working temperature of high-power WLEDs severely limit the further development of C-dot phosphors. In this paper, we report an efficient strategy to improve thermal dissipation within C-dot phosphors to solve the thermal quenching problem. C-dots/hexagonal boron nitride nanosheet (BNNS) hybrid nanostructures have been firstly prepared through an electrostatic assembly method. Owing to the effective heat transfer channels established by C-dots/BNNS in a polymer matrix, heat could be dissipated efficiently and the working temperature of WLEDs is reduced by 29 °C, suggesting excellent thermal quenching-resistance properties. Particularly, the hybrids show thermally stable emission without obvious emission loss up to 100 °C. Moreover, the C-dots/BNNS-WLEDs still maintain a high color rendering index of Ra > 89, revealing that the present strategy could promote the exploration of carbon phosphors with thermal quenching resistance for high-quality LED applications.

Ultrasensitive detection of transcription factors with a highly-efficient diaminoterephthalate fluorophore via an electrogenerated chemiluminescence strategy.

Herein, we apply an electrogenerated chemiluminescence (ECL) based method employing a diaminoterephthalate analogue as an ECL emitter and hairpin DNA as an amplification strategy, for the sensitive assay of transcription factors, which has enormous potential in actual biological detection.

Quench-resistant and stable nanocarbon dot/sheet emitters with tunable solid-state fluorescence via aggregation-induced color switching.

Nanocarbon fluorescence materials are promising color converters for multicolor emission via phosphor-coated light emitting devices (LEDs). Herein, a facile time-controlled solvothermal route was developed to prepare solid-state multicolor nanocarbon emitters comprising dot/sheet nanohybrids. The nanocarbons demonstrate an aggregation-induced color switching behavior, leading to tunable light emission from blue to yellow by modulating the solvothermal reaction time. Particularly, these emitters show outstanding film-forming ability directly and a high production yield (∼40%). Moreover, the nanocarbon-coated ultraviolet LEDs exhibit high quality multicolor light emission and excellent color stability at high voltages, impelling the development of emerging carbon phosphors in fundamental research studies and practical applications.