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The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here, we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse embryos. The allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early embryos. Collectively, allele-specific epigenomic reprogramming is different in humans and mice. [ABSTRACT FROM AUTHOR]

The advancement of fluorescence microscopy techniques has opened up new opportunities for visualizing proteins and unraveling their functions in living biological systems. Small‐molecule organic dyes, which possess exceptional photophysical properties, small size, and high photostability, serve as powerful fluorescent reporters in protein imaging. However, achieving high‐contrast live‐cell labeling of target proteins with conventional organic dyes remains a considerable challenge in bioimaging and biosensing due to their inadequate cell permeability and high background signal. Over the past decade, a novel generation of fluorogenic and cell‐permeable dyes has been developed, which have substantially improved live‐cell protein labeling by fine‐tuning the reversible equilibrium between a cell‐permeable, nonfluorescent spirocyclic state (unbound) and a fluorescent zwitterion (protein‐bound) of rhodamines. In this review, we present the mechanism and design strategies of these fluorogenic and cell‐permeable rhodamines, as well as their applications in bioimaging and biosensing. [ABSTRACT FROM AUTHOR]

Taking the Madoi MS 7.4 earthquake of 21 May 2021 as an example, this paper proposes using time series prediction models to predict the outgoing long-wave radiation (OLR) anomalies and study short-term pre-earthquake signals. Five time series prediction models, including autoregressive integrated moving average (ARIMA) and long short-term memory (LSTM), were trained with the OLR time series data of the aseismic moments in the 5° × 5° spatial range around the epicenter. The model with the highest prediction accuracy was selected to retrospectively predict the OLR values during the aseismic period and before the earthquake in the area. It was found, by comparing the predicted time series values with the actual time series value, that the similarity indexes of the two time series before the earthquake were lower than the index of the aseismic period, indicating that the predicted time series before the earthquake significantly differed from the actual time series. Meanwhile, the temporal and spatial distribution characteristics of the anomalies in the 90 days before the earthquake were analyzed with a 95% confidence interval as the criterion of the anomalies, and the following was found: out of 25 grids, 18 grids showed anomalies—the anomalies of the different grids appeared on similar dates, and the anomalies of high values appeared centrally at the time of the earthquake, which supports the hypothesis that pre-earthquake signals may be associated with the earthquake. [ABSTRACT FROM AUTHOR]

Numerous scholars have used traditional thermal anomaly extraction methods and time series prediction models to study seismic anomalies based on longwave infrared radiation data. This paper selected bidirectional long short-term memory (BILSTM) as the research algorithm after analyzing and comparing the prediction performance of five time series prediction models. Based on the outgoing longwave radiation (OLR) data, the time series prediction model was used to predict the infrared longwave radiation values in the spatial area of 5° × 5° at the epicenter for 30 days before the earthquake. The confidence interval was used as the evaluation criterion to extract anomalies. The examples of earthquakes selected for study were the Yangbi Ms6.4-magnitude earthquake in Yunnan on 21 May 2021 and the Luding Ms6.8-magnitude earthquake in Sichuan on 5 September 2022. The results showed that the observed values of the Yangbi earthquake 15 to 16 days before the earthquake (5 May to 6 May) exceeded the prediction confidence interval over a wide area and to a large extent. This indicates a strong and concentrated OLR anomaly before the Yangbi earthquake. The observations at 27 days (9 August), 18 days (18 August), and 8 days (28 August) before the Luding earthquake exceeded the prediction confidence interval in a local area and by a large extent, indicating a strong and scattered OLR anomaly before the Luding earthquake. Overall, the method used in this paper extracts anomalies in both spatial and temporal dimensions and is an effective method for extracting infrared longwave radiation anomalies. [ABSTRACT FROM AUTHOR]

A Rogowski coil based sensor for current measurement in a cryogenic environment and results of its application for paralleled high temperature superconducting (HTS) coil current sharing are presented. The current sensor consists of a Rogowski coil and an integrator, where the coil output voltage is proportional to the derivative of primary current and the integrator transfers the differentiation to normal state. The Rogowski coil has promising applicability at cryogenic circumstance because its body is made of low temperature materials. The integrator ensures a large bandwidth with feasible magnitude, which is vital for dynamic current measurement during the quench of the HTS coil. The proposed current sensor is used for current sharing measurement of two paralleled Bi2223 HTS coils, and the experimental results show that the measurement precision is better than 0.5%.

The application of reinforcement learning (RL) methods of artificial intelligence for penetration testing (PT) provides a solution to the current problems of high labour costs and high reliance on expert knowledge for manual PT. In order to improve the efficiency of RL algorithms for PT, existing research has considered bringing in the knowledge of PT experts and combining it with the use of imitative learning methods to guide the agent in its decision-making. However, the disadvantage of using imitation learning is also obvious; that is, the performance of the strategies learned by the agent hardly exceeds the demonstrated behaviour of the expert and it can also cause expert knowledge overfitting. At the same time, the expert knowledge in the currently proposed method is poorly interpretable and highly scenario-dependent. The expert knowledge used in these methods is not universal. To address these issues, we propose an intelligent PT framework named DQfD-AIPT. The framework encompasses the process of collecting and using expert knowledge and provides a rational definition of the structure of expert knowledge. To solve the overfitting problem, we perform PT path planning based on the deep Q-learning from demonstrations (DQfD) algorithm. DQfD combines the benefits of RL and imitation learning to effectively improve the PT strategy and performance of agents while avoiding overfitting. Finally, we conducted experiments in a simulated network scenario containing honeypots. The experimental results proved the effectiveness of expert knowledge incorporation. In addition, the DQfD algorithm can improve the efficiency of penetration testing more effectively than that by the classical deep reinforcement learning (DRL) method and can obtain a higher cumulative reward. Not only that, due to the incorporation of expert knowledge, in scenarios with honeypots, the DQfD method can effectively reduce the probability of interacting with honeypots compared to the classical DRL method. [ABSTRACT FROM AUTHOR]

In a cryogenic liquid medium, shock waves will be formed by the expansion of compressed gas that has been vaporized due to the injection of a large amount of energy. This may severely threaten the reliability of high- T c superconducting (HTS) apparatus. Several studies have documented the destructive forces of evaporating nitrogen produced by arc energy. However, the properties of and propagation mechanisms relating to pressure waves in liquid nitrogen have yet to be understood. The aim of this study was to clarify the evolution of pressure waves within an enclosed pipeline and reveal the effects of several factors such as the pipe size and the injected energy on the shock-wave impact using explosion dynamics simulations. The results provide evidence for the strengthening of shock waves due to multiple reflection and superposition. In addition, analysis of the pressure impulse and effective strain reveals that, in the case of moderate injected energy, the overall shape of the inside wall of the pipe will remain unchanged except at the points closest to the explosion center; in contrast, the ends of the pipeline may suffer from more severe deformation. Finally, the calculations suggest that the shock-wave impact increases almost linearly with the injected energy, and in logarithmic coordinates, the pressure is inversely proportional to the explosion distance. These findings provide a better understanding of the characteristics and propagation patterns of shock waves in liquid nitrogen, and they lay a foundation for evaluating the safety of HTS cables and energy pipelines. [ABSTRACT FROM AUTHOR]

The penetration test has many repetitive operations and requires advanced expert knowledge, therefore, the manual penetration test is inefficient. With the development of reinforcement learning, the intelligent penetration test has been a research hotspot. However, the existing intelligent penetration test simulation environments only focus on the exploits of target hosts by the penetration tester agent's actions while ignoring the important role of social engineering in the penetration test in reality. In addition, the construction of the existing penetration test simulation environment is based on the traditional network graph model without integrating security factors and attributes, and it is difficult to express the interaction between the penetration tester and the target network. This paper constructs an improved network graph model for penetration test (NMPT), which integrates the relevant security attributes of the penetration test. The NMPT model lays the foundation for extending the penetration tester's social engineering actions. Then, we propose an intelligent penetration test method that incorporates social engineering factors (SE-AIPT) based on the Markov Decision Process. We adopt several mainstream reinforcement learning algorithms to train attack agents. The experiments show that the SE-AIPT method could vividly model the penetration tester agent's social engineering actions, which effectively improves the reality of the simulation environment. Moreover, the penetration tester agent shows superior effects in the attack path discovery in the intelligent penetration test simulation environment constructed by the SE-AIPT method. [ABSTRACT FROM AUTHOR]

Air plasma is commonly used to treat water for activation or purification, and plasma-activated water (PAW) is a promising green disinfectant that has attracted much attention in recent years. However, either the O3 discharge mode or the NO x discharge mode of air plasma lacks efficiency for water activation, mainly due to the low solubility of O3, NO and NO2. The transition process between those two modes could produce high-valence NO x such as N2O5 which should be more efficient for water activation, but this process is not easily controlled and water activation by N2O5 has rarely been reported before. In this letter, N2O5 is found to be produced effectively and stably by mixing the effluent gases of a NO x mode air plasma, produced by gliding arc discharge, and an O3 mode air plasma, produced by dielectric barrier discharge. The mixed gas rich in N2O5 is found to be very efficient for water activation. A colony-forming unit reduction of nearly 6 logs was achieved for a methicillin-resistant Staphylococcus aureus suspension by using PAW treated by the mixed gas, and the high bactericidal effect of the PAW could persist for more than 1 h after the plasma activation. The main reactive species for the bactericidal effect in the PAW are discussed, and the chemical pathways for N2O5 production and its usage for water activation are illustrated. [ABSTRACT FROM AUTHOR]

Cutaneous melanoma (CM) is attracting increasing attention due to high mortality. In response to this, we synthetically analyze the CM dataset from the TCGA database and explore microenvironment-related genes that effectively predict patient prognosis. Immune/stromal scores of cases are calculated using the ESTIMATE algorithm and are significantly associated with overall patient survival. Then, differentially expressed genes are identified by comparing the immune score and stromal score, also prognostic genes are subsequently screened. Functional analysis shows that these genes are enriched in different activities of immune system. Moreover, 19 prognosis-related hub genes are extracted from the protein-protein interaction network, of which four unreported genes (IL7R, FLT3, C1QC, and HLA-DRB5) are chosen for validation. A significant negative relationship is found between the expression levels of the 4 genes and pathological stages, notably T grade. Furthermore, the K-M plots and TIMER results show that these genes have favorable value for CM prognosis. In conclusion, these results give a novel insight into CM and identify IL7R, FLT3, C1QC, and HLA-DRB5 as crucial roles for the diagnosis and treatment of CM. [ABSTRACT FROM AUTHOR]

Plasma‐activated media (PAM), the product of cold atmospheric plasma (CAP) acting on aqueous media, has similarly strong biological activity and some unique advantages compared with CAP for biomedical targets. However, no reliable PAM‐preparing device with high safety for medical uses has yet been developed, limiting the advancement of PAM clinical trials. Herein, an integrated device for PAM preparation with a maximum yield of 4.8 L/hr is reported in detail. A large‐area CAP is generated by the plasma‐generating module based on the surface dielectric barrier discharge. Several sensors and controllers are applied in this device to stabilize the discharge environment and PAM consistency. In the in vitro experiments, PAM prepared in this device exhibits the bactericidal property of up to 6 logs reduction against various clinical pathogens with multi‐drug resistance. The high bactericidal effect of PAM can be preserved for ∼10 min. After constructing the mice model by cecal ligation and puncture, it is found that the abdominal injection of PAM can effectively relieve sepsis‐induced systemic toxicity and maintain homeostasis, which is mainly attributed to the anti‐infective efficacy of PAM. The third‐party testing confirms that the soaking bactericidal rates of PAM to S. aureus and E. coli are respectively higher than 99.99% and 99.999%, while the acute oral toxicity, skin irritation, and oral genotoxicity of PAM are negligible. This study provides a practical approach for preparing PAM with high reliability, which shows an excellent prospect of clinical applications and commercialization. [ABSTRACT FROM AUTHOR]

Fluorescent light‐up RNA aptamers (FLAPs) have become promising tools for visualizing RNAs in living cells. Specific binding of FLAPs to their non‐fluorescent cognate ligands results in a dramatic fluorescence increase, thereby allowing RNA imaging. Here, we present a color‐shifting aptamer‐fluorophore system, where the free dye is cyan fluorescent and the aptamer‐dye complex is near‐infrared (NIR) fluorescent. Unlike other reported FLAPs, this system enables ratiometric RNA imaging. To design the color‐shifting system, we synthesized a series of environmentally sensitive benzopyrylium‐coumarin hybrid fluorophores which exist in equilibrium between a cyan fluorescent spirocyclic form and a NIR fluorescent zwitterionic form. As an RNA tag, we evolved a 38‐nucleotide aptamer that selectively binds the zwitterionic forms with nanomolar affinity. We used this system as a light‐up RNA marker to image mRNAs in the NIR region and demonstrated its utility in ratiometric analysis of target RNAs expressed at different levels in single cells. [ABSTRACT FROM AUTHOR]

In this article, a general scheme of a 40-kV/2-kA resistive type dc superconducting fault current limiter (SFCL) is suggested, which could be utilized to suppress the surge current caused by short-circuit faults in voltage-source-converter HVdc (VSC-HVdc) power grids. This dc SFCL is designed and fabricated with 6 coil modules in parallel and 4 in series. In order to investigate the current-limiting performance of the dc SFCL under the rapidly rising fault current, the SFCL is tested on the platform with a pulsed dc impact generator. Besides the property of current limitation, the current capacity, insulation and quench recovery performance of such SFCL are also tested. Results indicate that the critical current of SFCL is larger than 2050 A at 69 K, and the dc withstand voltage is larger than 74 kV in 2 h. During the 9-kV dc impact test, the short-circuit current could be limited to 8842 A, and the quench recovery time is less than 200 ms. [ABSTRACT FROM AUTHOR]

We develop an electric internal heating method based on a Ni-foam structured catalyst for CO2 methanation, in which the Joule heat generated by electric current passing through the catalyst drives the reaction. Compared with the conventional external heating method, EIH significantly enhances the catalytic activity and anti-poisoning ability of the catalyst. [ABSTRACT FROM AUTHOR]

Metastasis accounts for the vast majority of cancer deaths. To minimize metastasis-associated mortality, it is crucially important to evaluate the metastatic potential (M.P.), that is, defined as a tendency of a primary tumor to colonize a distant organ. Dysregulated pH in solid tumors, especially the acidification of extracellular pH (pHe) promotes dormant metastasis by driving protease-mediated digestion, disrupting cell-matrix interaction and increasing migration of cancer cells. Therefore, imaging intratumoral acidosis creates a unique opportunity to evaluate the M.P. In this work, a novel pH activatable probe was developed, in which two near-infrared (NIR) fluorophores were conjugated via a flexible and acid liable linkage. While the fluorescence of this probe is quenched due to intramolecular dimeric aggregate under neutral environment, the cleavage of pH liable linkage with the concomitant disruption of aggregates in acidic tumor microenvironment results in a remarkable fluorescence enhancement. This probe not only visualized the primary tumors with high target to background (T/B) signal ratio in vivo, but also revealed the correlation between the M.P. and acidosis distribution pattern in tumor. While the acidosis locate dispersedly at tumor periphery in highly metastatic tumor, it distribute more widely in lowly metastatic tumor and the acidification degree increases substantially from the margin to core areas. This pH activatable NIR fluorescent probe holds the potential to evaluate the M.P., monitor the therapeutic response and predict the prognosis by delineating acidosis in tumors. [ABSTRACT FROM AUTHOR]

An HTS magnet was designed for the 1 MJ/0.5 MVA SMES with Bi2223/Ag tapes. According to the design, it consists of 44 double pancakes with an inductance of 6.28 H, and the rated operating current is 565 A, the maximum magnetic field is up to 5.72 T. In this paper, the insulation of the tapes and the magnet, the fabrication and tests of the 44 double pancakes, the joints among double pancakes and the assemblage of the magnet are described in detail. And then, the fundamental performances testing of the magnet were carried out at liquid nitrogen and helium, respectively. With zero helium vaporization, the 1 MJ HTS magnet was dip in liquid helium and cooled with four G-M cryocoolers. After the whole 1 MJ/0.5 MVA SMES were field installed and tested, it had been put into operation since Feb. 16 of 2011 at a 10.5 kV superconducting power substation locating in Baiyin, Gansu Province of China. [ABSTRACT FROM PUBLISHER]