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Although the field of artificial intelligence (AI) has rapidly developed, there has been little research to review, describe, and analyse the trends and development of empirical research on AI-supported language learning. This paper selected and analysed 25 empirical research papers on AI-supported language learning published in the last 15 years. These empirical studies were analysed using the activity theory from seven constituents: tool, subject, object, rules, community, division of labour, and outcome. A key contribution of this paper is the use of activity theory to illustrate the dynamic interactions and contradictions between the seven elements. AI-supported technology as a mediating tool demonstrated some effectiveness in language learning but needs further improvement in the use of language for communication and collaborative design. We argue that teachers’ intervention and configuration of AI-supported language learning in the pedagogical design plays an important role in the effectiveness of learning. More research is needed to explore the use of AI-supported language learning in the classroom or the real-life learning context. Implications for practice or policy: Research on AI-supported language learning should view teacher and students as active agents in interacting with technology and making transformations in real life learning situations. More research should focus on productive dialogue and communication in AI-supported language learning with collaborative design. A mixed module of AI-supported language learning and formal teacher instruction should be incorporated in pedagogical design.

Synthesis of a specific As(iii)-ion-imprinted polymer for oxidation liquid phase color detection of As(iii) ions in aqueous system.

Based on the deformation and damage characteristics of the surrounding rock in a large-section gob-side entry retaining and combined with field observations and an analysis of the dominant factors, an overall deformation control plan is formulated. The plan mainly includes a structure of high strength, high stiffness and high ductility for roadside support; the reinforcement of the roadway-in support; and the setup entry hydraulic fracturing pressure release mechanism and advanced long, horizontal borehole “fracturing-jet” pressure relief technology. Industrial field tests were completed taking Tangan coal mine as the engineering background. The research shows that the large-section gob-side entry retaining has the typical “asymmetric” overall deformation and damage characteristics, including top coal sinking along the inner side of the roadside support, the whole roadside support structure skewing, and even splitting damage; floor heaving; and the coal-side bolt support structure basically losing support ability and bulging out from the coal side. The dominant factors of deformation damage are disintegration of the floor mudstone by water and deflection deformation under horizontal stress, splitting damage in the concrete roadside support under asymmetric load, damage and expansion due to the insufficient strength of the coal side support, strong dynamic pressure on the roof, and the mutual influence of support and pressure relief. The industrial test shows that the deformation control scheme optimizes the stress environment of the gob-side entry retaining space, the deformation control effect is remarkable, and the roadside fully meets the reuse requirements.

Currently, Luzhou in the Sichuan Basin is a focal point for shale-gas exploration and development in China. However, a lack of detailed research on the mineral composition of the Wufeng Formation-Longmaxi Formation (WF-LF) shale is hindering the extraction of deep-buried shale gas in the Luzhou shale play. Herein, a field emission scanning electron microscope (FESEM) equipped with the Advanced Mineral Identification and Characterization System (AMICS) software was employed to analyze the mineral composition of the WF-LF shale from six wells in Luzhou. Quartz was the dominant mineral type, (16.9–87.21%, average 51.33%), followed by illite, calcite, dolomite, and pyrite. Our study revealed that (1) quartz content showed a moderate positive correlation with the total organic carbon (TOC) content, indicating that the quartz found in the shale is mostly of biological origin; and (2) the sum content of siliceous minerals and carbonaceous minerals was moderately positively correlated with the brittleness index (BRIT) in well SS1H2-7 and in the well group of RS8 and RS5, indicating that the siliceous minerals and carbonaceous minerals had an active effect on reservoir compressibility. Finally, according to the mineralogical features of each sublayer, we identified four types of reservoirs to determine their scope for exploration.

The constant false-alarm-rate (CFAR) target detection is an important research direction for synthetic aperture radar (SAR) image application. The traditional pixel-level CFAR method has great shortcomings in eliminating the false-alarm targets and keeping the complete information of the targets. Thus, the superpixel-level CFAR has become an important topic in research in recent years. However, the current superpixel-level CFAR methods have not considered or built a superpixel clutter-distribution model. Therefore, an improved CFAR based on superpixel modeling is proposed in this letter. A superpixel-level compound Gamma distribution was built to describe the clutter statistical model, which can obtain a more accurate fitting than the pixel-level Gamma distribution. The experiments on the SAR images verified that the proposed method can effectively suppress the influence of the background clutter to reduce the false alarms and can keep the complete shape information of the targets. As a result, the proposed method outperforms the traditional pixel-level CFAR and the current superpixel-level CFAR methods.

An ultra-sensitive and selective electrochemical sensor was proposed through the combination of carbon disulfide-functionalized graphene oxide (GOCS) composite with high conductivity and cadmium ion-imprinted polymer (IIP). Using pyrrole as the functional monomer and Cd

To investigate the diagnostic accuracy of subtraction coronary computed tomographic angiography (CCTAIn this study, 180 patients with coronary calcified plaques who underwent both coronary CT angiography and invasive coronary angiography (ICA) were prospectively enrolled at five centers. Patients were divided into three groups according to the Agatston score: group A (low to moderate,400), group B (high, 400-999), and group C (very high, ≥ 1000). Diagnostic accuracies estimated by area under the receiver operating characteristic curve (AUC) were compared between conventional CCTA (CCTAThere were 86 patients in group A, 44 in group B, and 50 in group C. In identifying ≥ 70% coronary stenosis, subtraction improved the diagnostic accuracies on a per-segment basis in group B (AUC: 0.80 vs 0.92, p = 0.001) and group C (AUC: 0.75 vs 0.84, p = 0.001) after subtraction. When identifying ≥ 50% coronary stenosis, the per-segment AUC of CCTASubtraction achieved better diagnostic accuracy in patients with Agatston score ≥ 400, both in identifying ≥ 50% and ≥ 70% coronary stenosis, which was instructive for the application of subtraction in clinical practice.

Although the role of emotions in preservice teacher agency in innovation is well acknowledged, little is known about how emotions relate to their epistemic agency. This study explores the link betw...

A novel hydrophilic As(V) ion-imprinted cryogel (IIC) was green prepared by cryogelation in aqueous environment which was coincident with the adsorption condition and can improve the specific recognition performance. The methacrylamido propyl trimethyl ammonium chloride (MPTAC) was selected as the functional monomer and the saturated adsorption capacity of the prepared IIC and NIC were 55.0 mg/g and 29.4 mg/g, and with high imprinting factor of 1.87. Additionally, the prepared IIC showed admirable reusability and high selectivity, and the recovery was in the range 81.2-97.9% with RSD range of 1.9-4.3%, which was similar to the value obtained by hydride generation atomic absorption spectrometry. IIC can be used as solid material for colorimetric detection at the ultraviolet wavelength of 858 nm without color interference of material matrix, in the range 5-200 μg/L (R

We theoretically and experimentally investigate a phase-modulated frequency-shifting loop (PM-FSL) that includes an electro-optic phase modulator (EOPM) and a gain element, and is seeded by a single-frequency laser. By slightly detuning the modulation frequency of the EOPM off an integer multiple of the fundamental loop frequency, we generate an output waveform that exhibits a series of pulse doublets modulated at radio frequency (RF). We prove that the series consists of sinusoidal frequency-modulated (SFM) pulse doublets whose repetition rate and bandwidth are easily reconfigurable. We report the generation of the SFM waveforms with bandwidth above 7 GHz (limited by the detection bandwidth) by simply tuning the input RF tone over a span of a few kHz in the vicinity of 14.58 MHz (the round-trip frequency). The system is modeled using a time-delayed interference model that accounts for the modulation function of the EOPM, the loop delay time, and the detuning parameter. The model explains the formation of SFM pulse doublets and effectively reproduces all the experimental waveforms. This well-defined waveform may find applications in RF-optical signal processing and radar systems.

This research investigated Australian community languages school (CLS) teachers’ emerging pedagogical habitus, focussing specifically on key dynamics effecting the adaptation in their pedagogical u...

Wenwei Nong,1,* Liping Ma,2,* Biyang Lan,1 Ning Liu,1 Hongzhi Yang,1 Xiaoxia Lao,2 Qiaomei Deng,2 Zhihu Huang2 1Department of General Surgery, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, People’s Republic of China; 2Department of Clinical Laboratory, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zhihu HuangAffiliated Minzu Hospital of Guangxi Medical University, Nanning, People’s Republic of ChinaEmail hoftiger@126.comBackground: Hepatitis B virus infection co-occurs in 33% of individuals with hepatocellular carcinoma worldwide. However, the molecular link between hepatitis B virus and hepatocellular carcinoma is unknown. Thus, we aimed to elucidate molecular linkages underlying pathogenesis through in-depth data mining analysis.Materials and Methods: Differentially expressed genes were identified from patients with chronic hepatitis B virus infection, hepatocellular carcinoma, or both. Gene set enrichment analysis revealed signaling pathways involving differentially expressed genes. Protein-protein interaction networks, protein crosstalk, and enrichment were analyzed to determine whether differentially expressed gene products might serve as a bridge from hepatitis B virus infection to hepatocellular carcinoma pathogenesis. Prognostic potential and transcriptional and post-transcriptional regulators of bridge genes were also examined.Results: We identified vital bridge factors in hepatitis B virus infection-associated hepatocellular carcinoma. Differentially expressed genes were clustered into modules based on relative protein function. Signaling pathways associated with cancer, inflammation, immune system, and microenvironment showed significant crosstalk between modules. Thirty-two genes were dysregulated in hepatitis B virus infection-mediated hepatocellular carcinoma. CPEB3, RAB26, SLCO1B1, ST3GAL6 and XK had higher connectivity in the modular network, suggesting significant associations with survival. CDC20 and NUP107 were identified as driver genes as well as markers of poor prognosis.Conclusion: Our results suggest that the sustained inflammatory environment created by hepatitis B virus infection is a risk factor for hepatocellular carcinoma. The identification of hepatitis B virus infection-related hepatocellular carcinoma bridge genes provides testable hypotheses about the pathogenesis of hepatocellular carcinoma.Keywords: signaling pathways, molecular processes, protein-protein interactions, chronic hepatitis B virus infection, hepatocellular carcinoma

An appropriate well spacing plan is critical for the economic development of shale gas reservoirs. The biggest challenge for well spacing optimization is interpreting the subsurface uncertainties associated with hydraulic and natural fractures. Another challenge is the existence of complex natural fractures. This work applied an integrated well spacing optimization workflow in shale gas reservoirs of the Sichuan Basin in China with both hydraulic and natural fractures. The workflow consists of five components: data preparation, reservoir simulation, estimated ultimate recovery (EUR) analysis, economic calculation, and well spacing optimization. Firstly, the multiple realizations of thirteen uncertain parameters of matrix and fractures, including matrix permeability and porosity, three relative permeability parameters, hydraulic fracture height, half-length, width, conductivity, water saturation, and natural fracture number, length, and conductivity, were captured by the assisted history matching (AHM). The fractures were modeled by the embedded discrete fracture model (EDFM) accurately and efficiently. Then, 84 AHM solutions combining with five well spacing scenarios from 517 ft to 1550 ft would generate 420 simulation cases. After reservoir simulation of these 420 cases, we forecasted the long-term gas production for each well spacing scenario. Gas EUR degradation and well interference would imply the critical well spacing. The net present value (NPV) for all scenarios would be calculated and trained by K -nearest neighbors (KNN) proxy to better understand the relationship between well spacing and NPV. In this study, the optimum well spacing was determined as 793 ft, corresponding with a maximum NPV of 18 million USD, with the contribution of hydraulic fractures and natural fractures.

In this work, the Metal-rich phase Chromium Aluminum (CrAl)/Ceramic phase Chromium Aluminum Nitride (CrAlN) multi-layer coatings were prepared by Arc Ion Plating (AIP). The micro-structure and phase composition of CrAl/CrAlN multi-layer coatings were characterized, and the microstructure, mechanical properties, residual stress and fracture toughness of the coating were emphatically analyzed. It has been found out that the residual stress of the multi-layer coating was only −0.932 ± 0.065 GPa, which was significantly lower than that of the mono-layer coating for −1.569 ± 0.093 GPa. At the same time, it was also found that the preferred growth orientation of the coating changed from a mono-layer (111) to a multi-layer (200) crystal plane. The hardness of the multi-layer (22.74 ± 0.57 GPa) is slightly lower than that of the mono-layer (24.92 ± 0.5 GPa), and the adhesion strength (46.2 ± 3.8 N) is obviously higher than that of the mono-layer (37.4 ± 2.4 N), and the fracture toughness is also higher (8.7 ± 0.8 MPa m1/2). In addition, the mechanism of crack initiation and propagation in stress-induced coatings was studied in detail on the basis of the structure of micro-nano CrAl/CrAlN multi-layer coatings.

Development of conceptually novel and practically useful bioconjugation reactions has been an intense pursuit of chemical biology research. Herein, we report an unprecedented bioconjugation reaction that hinges on a chemical trigger-enabled inverse-electron-demand Diels–Alder (IEDDA) cycloaddition of trans-cycloheptene (TCH) with tetrazine. Unlike the conventional strain-promoted bioconjugation reactions that utilize built-in strained alkenes as reactants, the current one features a “trigger-release-conjugate” reaction model, in which a highly strained TCH species is released from a bench-stable bicyclic N-nitrosourea (BNU) derivative upon treatment with an external stimulus. It is noteworthy that the reactivity–stability balance of BNU derivatives could be tuned by manipulating their N-1 substituents. As a proof-of-concept case, this new chemical trigger-enabled IEDDA reaction has been applied to in vitro protein labeling and pretargeted cell imaging. This work opens a new avenue to utilize BNU derivatives as a new class of chemical reporters in bioconjugate chemistry.

The nutrition and functionality of Chenopodium quinoa Willd are closely related to its components; however, these properties vary widely in different varieties of C. quinoa Willd from different origins. Using ultrahigh-performance liquid chromatography coupled with high-field quadrupole-orbitrap high-resolution mass spectrometry (UHPLC-QE HF HRMS) for metabolomics analysis, we performed nontargeted metabolomics analysis of C. quinoa Willd of different color varieties and origins and evaluated the texture characteristics after cooking. Both the variety and origin significantly affected the metabolic characteristics of C. quinoa Willd. The differences in the composition and texture properties were closely related to the lipid, amino acid, and polyphenol contents. The contents of kaempferol, catechol, myricetin 7-(6'-galloside), tyrosine, prostaglandin I2, and glutathione in white, red, and black quinoa significantly differed, and the variety had a greater effect on the lipid content than on the polyphenol and amino acid contents. At the same processing level, the texture properties of white and red quinoa were better than those of black quinoa. Furthermore, the contents of differential polyphenols and amino acids in Gansu white quinoa were higher than those in quinoa from the other three producing areas. The contents of differential polyphenols and terpenoids in Inner Mongolia white quinoa were relatively low, whereas in Shanxi white quinoa, the contents of differential amino acids were relatively low and those of differential terpenoids were relatively high. The levels of quercetin and its derivatives, kaempferol and its derivatives, 9-HODE, azelaic acid, sebacic acid, elaidic acid, linoleic acid, prostaglandin H2, glutathione, 5-aminovaleric acid, and other compounds significantly differed in quinoa from different origins; thus, these compounds can be used as metabolic markers to identify the origin of quinoa. The texture properties of white quinoa from Qinghai and Inner Mongolia were better than those of white quinoa from Gansu and Shanxi. Although C. quinoa Willd can tolerate harsh environments, its grain quality varies widely. Cultivating C. quinoa Willd varieties according to local conditions is important for improving their yield and quality.

Geological disasters damage highways and disrupt traffic, which reduces the service level of roads. We collected 15,435 geohazards in Guangxi Province. The geohazards within 1km of the highway buffer were selected to study its spatial distribution characteristics and risk assessment methods. Geohazard intensity index and sensitivity index are proposed to establish the highway geohazards assessment model. Based on the weights of evidence (WOE) method, the influencing factors of the sensitivity index and the weight of each factor are obtained. By analyzing the spatial distribution characteristics of geohazards, collapses, landslides, ground collapse and unstable slopes are identified as major geohazards along the highway. Based on the Getis-Ord Gi* statistic methods, the hotspot map of four disasters was drawn, and the intensity index along the highway was calculated. The relationship between slope, aspect, topographic relief, annual average rainfall, land use, lithology type and geohazards was analyzed. The sensitivity index was calculated using the WOE method. The intensity index and the sensitivity index were superimposed to obtain the geohazard index, and the geohazard risk of the highway is divided into five levels. The model accuracy-test based on the receiver operating characteristic (ROC) curve shows that Area Under Curve (AUC) equals 0.71, indicating high reliability for the risk assessment.

The NiCoCrAlYTa coating deposited on Ni-based superalloy using arc ion plating (AIP) technology was subjected to isothermal oxidation in air at 1050°C for up to 200 h. The microstructure, oxides sc...

Background No guideline recommends antiviral therapy for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients with persistently normal alanine aminotransferase levels and a high hepatitis B virus (HBV) DNA viral load. Aim To evaluate the feasibility and safety of a Chinese herbal formula as a therapeutic option for chronic HBV infection. Methods In total, 395 patients (30-65 years old) with confirmed HBeAg-positive chronic hepatitis B infection and persistently normal alanine aminotransferase were randomized to receive either Chinese herbal formula or placebo for 96 wk. Endpoints to evaluate therapeutic efficacy included: (1) HBV DNA levels decreased to less than 4 log10 IU/mL at weeks 48 and 96; and (2) HBeAg clearance and seroconversion rates at weeks 48 and 96. Results HBV DNA levels ≤ 4 log10 IU/mL were 10.05% at week 48 and 18.59% at week 96 in the treatment group. The HBeAg clearance and conversion rates were 8.54% and 8.04% at week 48 and 16.08% and 14.57% at week 96, respectively. However, HBV DNA levels ≤ 4 log10 IU/mL were 2.55% and 2.55% at weeks 48 and 96, respectively, and the HBeAg clearance rates were 3.06% and 5.61% at weeks 48 and 96, respectively, in the control group. The quantitative hepatitis B surface antigen and HBeAg levels at baseline and changes during the treatment period as well as the alanine aminotransferase elevation at weeks 12 and 24 were strong predictors of HBeAg clearance. Conclusion High rates of HBV DNA reduction, HBeAg clearance and seroconversion could be achieved with Chinese herbal formula treatments, and the treatments were relatively safe for HBeAg-positive chronic hepatitis B-infected patients with persistently normal alanine aminotransferase. The ability of the compound to modulate host immune function probably contributed to this effect.

Anaerobic digestion of cattle manure has a low efficiency due to the high hydraulic retention time (HRT) required to degrade the abundant degradation-resistant compositions, co-digestion with food waste is effective at improving the methane production. Lowering the HRT can therefore increase the methanogenic efficiency during co-digestion. This study considered the effects of different HRTs (25, 20, 15, 10, 7, 5, and 4 days) on cattle manure and food waste co-digestion. The highest methane production was achieved at 1.48 L/L/d with an HRT of 5 days. The maximum methane yields (236–257 mL/g-VS) were attained at HRT ≥15 days and decreasing the HRT to 10-5 days resulted in low methane yields and complete process failure at HRT 4 days, due to volatile fatty acids accumulated and microorganisms washed out. From a high HRT of 20 days to a low HRTs of 5 days, Bacteroidetes and Firmicutes were the dominant bacteria and the percentage of syntrophic acetate oxidizing bacteria (mainly Pelotomaculum and Pseudothermotoga) clearly increased. The dominant methanogen changed from the acetotrophic Methanosaeta to the hydrogenophilic Methanobrevibacter. These results enable biogas plants to utilize surplus amounts of cow manure and food waste in a sustainable manner with high process capacity and methane recovery.

An unprecedented photoinduced azide–alkene cycloaddition has been developed, the key elements of which include the photoisomerization of cis-cycloheptenone to trans-cycloheptenone, strain-promoted 1,3-dipolar cycloaddition of trans-cycloheptenone with azide, and aerobic oxidative aromatization of the resulting 1,2,3-triazoline. The newly developed photoclick reactions display several appealing features including high overall efficiency, broad substrate scope, environmentally benign conditions, and operational simplicity, which provide an enabling tool for accessing structurally diverse 1,2,3-triazoles. In addition, the photoisomerization–cycloaddition strategy could also be extended to the 1,3-dipolar cycloadditions of trans-cyclooctenone with azide and trans-cycloheptenone with nitrile oxide. More appealingly, the title reaction has been successfully applied as a bioconjugation tool for in vitro protein labeling.

The nonanesthetic noble gas helium (He) can protect many organs against ischemia and reperfusion injury, such as liver and heart. However, the role of He on cardiac dysfunction during sepsis is not clear. In this study, we established a lipopolysaccharide (LPS)-induced cardiac dysfunction mouse model to examine the influence of He on the impaired cardiac function, and further investigated the possible innate immune mechanisms that may be involved. LPS induced left ventricular dysfunction and cavity enlargement, as indicated by decreased percent ejection fraction, percent fractional shortening, left ventricular anterior wall thickness in systole, and left ventricular posterior wall thickness in systole, while increased left ventricular end-systolic diameter and left ventricular end-systolic volume. He improved the impaired left ventricular function and cavity enlargement in a dose-dependent manner, and it was beneficial at 1.0 mL/100 g. Mechanistically, He inhibited toll-like receptor 4 (TLR4) expression, reduced the phosphorylation of nuclear factor κB (NF-κB), and subsequently alleviated tumor necrosis factor-alpha (TNF-α) and interleukin-18 (IL-18) expression in heart. Therefore, He protects against LPS-induced cardiac dysfunction in mice partially via inhibiting myocardial TLR4-NF-κB-TNF-α/IL-18 signaling.

The disturbance of the highway construction to the terrain and the natural environmental factors are the main causes of the geohazards along the highway. We collected geohazards along the highway in Shandong Province and put forward the comprehensive geohazard index to reflect the risk of geohazards along the highway. The index consists of an intensity index describing the development of geohazards and a sensitivity index describing the potential risk of geohazards. The article uses an incomplete additive language matrix to calculate the weight of each index and factor. Based on the Getis-Ord Gi* statistic tool, the spatial distribution of landslides and collapses, debris flows, ground collapses, and unstable slopes are analyzed, and the geohazard intensity index is calculated by spatial superposition. The relationship between slope gradient, rainfall, vegetation coverage, rock type and geohazards is analyzed, and the geohazard sensitivity index is calculated by spatial superposition. Based on the comprehensive geohazard index and geomorphological characteristics, Shandong Province is divided into 4 geohazard first-level regions and 11 geohazard second-level regions, providing a basis for highway planning and construction.

Plakortin-type polyketides represent a growing family of sponge-derived marine natural products that display notable structural and biological diversity. In particular, a series of polycyclic plakortin polyketides, namely hippolachnin A and gracilioethers, have been identified in recent years, which attract immense interest from the synthetic community owing to their unique molecular architectures and promising biomedical potential. A number of elegant total syntheses of these targets and some synthetic studies have been performed through either bio-inspired or rationally designed strategies. This focused review aims to provide an up-to-date summary of the progress in the chemical synthesis of plakortin polyketides, with an emphasis on the key synthetic elements enabling the rapid assembly of their core skeletons.

Copy number variation (CNV) is one of the main structural variations in the human genome and accounts for a considerable proportion of variations. As CNVs can directly or indirectly cause cancer, mental illness, and genetic disease in humans, their effective detection in humans is of great interest in the fields of oncogene discovery, clinical decision-making, bioinformatics, and drug discovery. The advent of next-generation sequencing data makes CNV detection possible, and a large number of CNV detection tools are based on next-generation sequencing data. Due to the complexity (e.g., bias, noise, alignment errors) of next-generation sequencing data and CNV structures, the accuracy of existing methods in detecting CNVs remains low. In this work, we design a new CNV detection approach, called shortest path-based Copy number variation (SPCNV), to improve the detection accuracy of CNVs. SPCNV calculates the k nearest neighbors of each read depth and defines the shortest path, shortest path relation, and shortest path cost sets based on which further calculates the mean shortest path cost of each read depth and its k nearest neighbors. We utilize the ratio between the mean shortest path cost for each read depth and the mean of the mean shortest path cost of its k nearest neighbors to construct a relative shortest path score formula that is able to determine a score for each read depth. Based on the score profile, a boxplot is then applied to predict CNVs. The performance of the proposed method is verified by simulation data experiments and compared against several popular methods of the same type. Experimental results show that the proposed method achieves the best balance between recall and precision in each set of simulated samples. To further verify the performance of the proposed method in real application scenarios, we then select real sample data from the 1,000 Genomes Project to conduct experiments. The proposed method achieves the best F1-scores in almost all samples. Therefore, the proposed method can be used as a more reliable tool for the routine detection of CNVs.

Reliable estimates of hydraulic fracture geometry help reduce the uncertainty associated with estimated ultimate recovery (EUR) forecasts and optimize field developing planning in unconventional reservoirs. For these reasons, operators gather information from different sources with the objective to calibrate their hydraulic fracture models. Microseismic data is commonly acquired by operators to estimate hydraulic fracture geometry and to optimize well completion designs. However, relying solely on estimates derived from microseismic information may lead to inaccurate estimates of hydraulic fracture geometry. The objective of this study is to efficiently calibrate hydraulic fracture geometry by using microseismic data, physics-based fracture propagation models, and the embedded discrete fracture model (EDFM). We first obtain preliminary estimates of fracture geometry based on microseismic events’ spatial location and density with respect to the perforation cluster location. We then tune key completion parameters using an in-house fracture propagation model to provide hydraulic fracture geometries that are constrained by the microseismic cloud. In the history matching process, we included the effect of natural fractures, using the microseismic events location as natural fracture initiation points. Finally, we used cutoff coefficients to further reduce hydraulic fracture geometries to match production data. The results of this work showed a fast and flexible method to estimate fracture half-lengths and fracture heights, resulting in a direct indicator of the completion design. Additionally, hydraulic-natural fracture interactions were assessed. We concluded that the inclusion of cutoff coefficients as history matching parameters allows to derive realistic hydraulic and natural fracture models calibrated with microseismic and production data in unconventional reservoirs.

Photonic processing of microwave signals may offer higher bandwidth than conventional electronic methods [1] . Among various functions achievable by optical means, optical real-time Fourier transformation (RTFT) has received special attention because of its high processing speed, which is far beyond conventional digital signal processing methods. In this respect, the frequency-shifting loop (FSL) shows high performance, as compared to dispersion-based methods, by analyzing MHz-range bandwidth signals with a frequency resolution of a few kHz [2] . FSLs up to now mainly rely on the use of acousto-optic frequency shifters, with inherent limitations in efficiency when seeking a high bandwidth. To overcome this limitation, the use of electro-optic modulators inside FSLs was theoretically studied [3] . It was shown that phase modulators could be an alternative for realizing RF-photonic frequency-to-time mapping (FTM). Here we give some experimental support to the predictions of Ref. [3] , opening a new route to fully integrated microwave-photonic signal analyzers.

To a certain extent, building a personalized learning recommendation system based on learner differences and user needs as the center helps learners to acquire knowledge more efficiently and conveniently. The user model is the core part of the personalized learning recommendation system. It describes the learner’s personalized characteristics and different learning goals, and is the basis for the system to call domain resources and select push strategies. This article starts from the perspective of learners, based on the CELTS.11 learner model specification, combined with the characteristics of Chinese Bridge Chinese learners, and selects learner characteristics such as the user’s basic personal information, learning style, and knowledge level to reflect the differences between learners.. The user model researched and designed in this paper has certain applicable value, and has guiding significance for the follow-up improvement of the personalized learning recommendation system.