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Self-direction skill (SDS) is an essential 21st-century skill that can help learners be independent and organized in their quest for knowledge acquisition. While some studies considered learners from higher education levels as the target audience, providing opportunities to start the SDS practice by K12 learners is still rare. Further, practicing such skills requires a concrete context and scaffolding during the skill acquisition. This article introduces the Goal Oriented Active Learner (GOAL) system that facilitates SDS acquisition in learners utilizing daily activities as context. The GOAL architecture integrates learning logs from online environments and physical activity logs from wearable trackers to provide a data-rich environment for the learners to acquire and practice their SDS. The GOAL users follow DAPER, a five-phase process model, to utilize the affordances in the system while practicing SDS. We implemented the GOAL system at a K12 public institution in Japan in 2019. Learners used the online environments for extensive reading and smartwatches for tracking walking and sleeping activities. This study analyzes detailed interaction patterns in GOAL while learners planned and monitored their self-directed actions. The results illustrate the strategies for DAPER behaviors that emerge in different activity contexts. We discuss the potentials and challenges of this technology ecosystem that connects learners’ learning logs and physical activity logs, specifically in the K12 context in Japan and, more generally, from the learning analytics research perspective to provide a context to practice SDS.

Maize is one of the most successful crops in utilizing heterosis which significantly improves maize stresses resistance and yield. Drought is a destructive abiotic stress that significantly reduces crop yield, particularly in maize. Drought stress and re-watering frequently occur during the growth and development of maize; however, the molecular mechanisms of heterosis under drought stress and re-watering have rarely been systematically investigated. Zhengdan7137 and Zhengdan7153 are two maize hybrid varieties with robust heterosis, and separately belongs to the SS×NSS and Reid×Tangsipingtou heterotic groups. 54 transcriptomes of these two hybrids and their parental inbred lines were analyzed under well-watering (WW), water-deficit (WD), and re-watering (RW) conditions using RNA-Seq. In this study, we identified 3,411 conserved drought response genes (CDRGs) and 3,133 conserved re-watering response genes (CRRGs) between Zhengdan7137 and Zhengdan7153. When comparing CDRGs and CRRGs to overdominance and underdominance genes, we identified 303 and 252 conservative drought response overdominance genes (DODGs) and underdominance genes (DUDGs), respectively, and 165 and 267 conservative re-watering response overdominance genes (RODGs) and underdominance genes (RUDGs), respectively. DODGs are involved in stress response-related processes, such as L-phenylalanine metabolism, carbohydrate metabolism, and heat response, whereas DUDGs are associated with glucose metabolism, pentose-phosphate shunt, and starch metabolism. RODGs and RUDGs contribute to the recovery of hybrids from drought stress by upregulating cell propagation and photosynthesis processes, and repressing stress response processes, respectively. It indicated overdominant and underdominant genes conservatively contributed to hybrid heterosis under drought stress. These results deepen our understanding of the molecular mechanisms of drought resistance, uncover conservative molecular mechanisms of heterosis under drought stress and re-watering, and provide potential targets for improving drought resistance in maize.

RNA interference (RNAi) is a specific post-transcriptional gene-silencing phenomenon, which plays an important role in the regulation of gene expression and the protection from transposable elements in eukaryotic organisms. In Drosophila melanogaster, RNAi can be induced by microRNA (miRNA), endogenous small interfering RNA (siRNA), or exogenous siRNA. However, the biogenesis of miRNA and siRNA in these RNAi pathways is aided by the double-stranded RNA binding proteins (dsRBPs) Loquacious (Loqs)-PB, Loqs-PD or R2D2. In this study, we identified three alternative splicing variants of Loqs, namely Loqs-PA, -PB, and -PC in the orthopteran Locusta migratoria. We performed in vitro and in vivo experiments to study the roles of the three Loqs variants in the miRNA- and siRNA-mediated RNAi pathways. Our results show that Loqs-PB assists the binding of pre-miRNA to Dicer−1 to lead to the cleavage of pre-miRNA to yield matured miRNA in the miRNA-mediated RNAi pathway. In contrast, different Loqs proteins participate in different siRNA-mediated RNAi pathways. In exogenous siRNA-mediated RNAi pathway, binding of Loqs-PA or LmLoqs-PB to exogenous dsRNA facilitates the cleavage of dsRNA by Dicer−2, whereas in endogenous siRNA-mediated RNAi pathway, binding of Loqs-PB or Loqs-PC to endogenous dsRNA facilitates the cleavage of dsRNA by Dicer−2. Our findings provide new insights into the functional importance of different Loqs proteins derived from alternative splicing variants of Loqs in achieving high RNAi efficiency in different RNAi pathways in insects.

Abstract The development of technology enables diverse learning experiences nowadays, which shows the importance of learners’ self-regulated skills at the same time. Particularly, the ability to allocate time properly becomes an issue for learners since time is a resource owned by all of them. However, they tend to struggle to manage their time well due to the lack of awareness of its existence. This study, hence, aims to reveal how learners allocate their time and evaluate the effectiveness of the time allocation by examining its effects on learners’ performance. We collect the learning logs of 116 seventh-graders from the online learning system implemented in a Japanese public junior high school. We look at the data in the time window of 34 days before the regular exam. Even though clustering techniques as a Learning Analytics method help identify different groups of learners, it is seldom applied to group students’ learning patterns with different levels of indicators extracted from their learning process data. In this study, we adopt the method to cluster students’ patterns of time allocation and find that better performance can result from the consistency of study time throughout the exam preparation period. Practical suggestions are then proposed for different roles involved in digital learning environments to facilitate students’ time management. Collectively, this study is expected to make contributions to smart learning environments supporting self-regulated learning in the digital era.

Inner fracture zones play a decisive role in the formation of high-quality reservoirs in buried hill reservoirs in covered metamorphic rock. Based on core, sidewall core, thin section, seismic, logging and reservoir physical property data, the fracture development characteristics of the Bozhong 13-2 block buried hill reservoir are described in detail and the controlling factors and the influence on reservoir quality are discussed. The results showed: (1) three groups of tectonic fractures developed in the study area—near-EW-striking, ENE-striking and nearly N–S-striking fractures—were controlled by the early Indosinian thrusting, the late Indosinian to early Yanshanian sinistral strike-slipping and the late Yanshanian late dextral strike-slipping in the Bohai Bay Basin, respectively. The ENE- and nearly-E-W-striking fractures are the most common, and the dip angles of the fractures are mostly between 35° and 75° and thus oblique. (2) The Indosinian-early Yanshanian was the main fracture-forming period, and the dextral strike-slip action in the late Yanshanian was the key to maintaining effective fractures. Imaging logging shows that 97.87% of the fractures are effective fractures. Based on thin section observation, 14.47% of the fractures are unmodified open fractures and 80.37% of the fractures are effective fractures due to reactivation. (3) The late Yanshanian strike-slip fault transformed the deformation adjustment zone formed by the early Indosinian thrust faulting and the core of the fold structure was more conducive to fracture development. The fracture density of a single well located within the deformation adjustment zone and at the core of the fold is between 0.93–1.49 m−1, the fracture density of a single well located only at the core of the fold is between 0.67–0.75 m−1 and that of a single well located at the wing of the fold is between 0.35–0.59 m−1. Diabase dike intrusions promoted the development of local fractures. (4) Fractures promote the migration and accumulation of oil and gas, and the fracture density in the oil layer is between 0.81–2.19 m−1. That in the nonoil layer is between 0.25–1.12 m−1. In addition, fractures not only provide storage space but also effectively improve the reservoir capacity of the inner fracture zones of buried hill reservoirs by concentrating dissolution.

Stalk rot, a severe and widespread soil-borne disease in maize, globally reduces yield and quality. Recent documentation reveals that Pythium aristosporum has emerged as one of the dominant causal agents of maize stalk rot. However, a previous study of maize stalk rot disease resistance mechanisms and breeding had mainly focused on other pathogens, neglecting P. aristosporum. To mitigate crop loss, resistance breeding is the most economical and effective strategy against this disease. This study involved characterizing resistance in 295 inbred lines using the drilling inoculation method and genotyping them via sequencing. By combining with population structure, disease resistance phenotype, and genome-wide association study (GWAS), we identified 39 significant single-nucleotide polymorphisms (SNPs) associated with P. aristosporum stalk rot resistance by utilizing six statistical methods. Bioinformatics analysis of these SNPs revealed 69 potential resistance genes, among which Zm00001d051313 was finally evaluated for its roles in host defense response to P. aristosporum infection. Through virus-induced gene silencing (VIGS) verification and physiological index determination, we found that transient silencing of Zm00001d051313 promoted P. aristosporum infection, indicating a positive regulatory role of this gene in maize’s antifungal defense mechanism. Therefore, these findings will help advance our current understanding of the underlying mechanisms of maize defense to Pythium stalk rot.

Focus on the scheduling problem of distributed computing tasks in Internet of Vehicles. Firstly, based on the computing-aware network theory, a distributed computing resource model of the Internet of Vehicles is established, and the seven-dimensional QoS attributes of the computing resources in the Internet of Vehicles (reliability between computing resources, communication costs, computing speed and computing costs of the computing resources themselves , computing energy consumption, computing stability, and computing success rate) are grouped and transformed into two-dimensional comprehensive attribute priorities: computing performance priority and communication performance priority. Secondly, the weighted directed acyclic graph model of distributed computing tasks in the Internet of Vehicles and the seven-dimensional QoS attribute weighted undirected topology graph model of distributed computing resources in the Internet of Vehicles are respectively established. Moreover, a dynamic greedy algorithm-based task of loading and computing resource scheduling algorithm is proposed. Finally, the example analysis shows that the overall performance of this dynamic greedy algorithm-based task of loading and computing resource scheduling algorithm is better than the classic HEFT scheduling algorithm and round robin scheduling algorithm.

Abstract Hydrofluoroolefin HFO1234zeE (trans‐1,3,3,3‐tetrafluoroprop‐1‐ene) is an environmentally friendly gas insulating medium that has the potential to replace SF6. To clarify the decomposition paths and products of an HFO1234zeE/N2 gas mixture under partial discharge, the decomposition mechanism is explored with density functional theory. The results indicate that only HFO1234zeE molecules decompose in the range of low‐temperature plasma, and electrons with different energies interact with molecules and cause them to decompose through different paths. Then, products are generated by free radical recombination, addition reactions and internal configurational conversions of the molecule. An experimental investigation of decomposition of the HFO1234zeE/N2 gas mixture with different discharge modes is carried out, and it is found that the products calculated with density functional theory are consistent with those seen experimentally. The results show the decomposition mechanism of the insulating gas under partial discharge and provide a theoretical basis for the application of HFO1234zeE.

Based on the data associated with cores, sidewall cores, casting thin sections, reservoir physical properties, conventional logging and imaging logging, the classification schemes of vertical reservoir units are proposed for the two types of Archaeozoic buried hills (exposed and covered ones) in the Bozhong Sag, Bohai Bay Basin. The geological characteristics and storage spaces of these reservoir units are described, and their identification markers in conventional and imaging log curves are established. The Archaeozoic metamorphic buried hills can be vertically classified into two primary reservoir units: weathering crust and inner buried hill. The weathering crust contains four secondary units, i.e., the clay zone, weathered glutenite zone, leached zone, disaggregation zone; and the interiors contain two secondary units, i.e., interior fracture zone and tight zone. In particular, the inner fracture zone was further divided into cataclasite belts and dense-fracture belts. It is proposed that the favorable reservoirs of exposed Archaeozoic metamorphic buried hills are mainly developed in four parts including weathered glutenite zone, leached zone, disintegration zone superposed with the cataclasite belt and the cataclasite belt of inner fracture zone, and are controlled by both weathering and tectonic actions. Favorable reservoirs in covered Archaeozoic metamorphic buried hills are mainly developed in the weathering crust superposed with the cataclasite belts and the cataclasite belts of inner fracture zone, and are mainly controlled by tectonic actions.

Abstract Target parameter estimation is considered for the cooperative multiple‐input multiple‐output (MIMO) radar and MIMO communications system. To address the hardware limitation of the radar system, a joint transmitter selection and receiver placement (JTSRP) problem is formulated to minimise the estimation performance benchmarked by the Cramer–Rao bound (CRB), where the transmitters can be selected from a discrete set and the receivers can be deployed over a continuous region. To efficiently solve this mix‐integer non‐linear programming problem approximately, a genetic algorithm (GA)‐based method is proposed. It is shown that the result obtained by the proposed algorithm is close enough to the optimum solution of the JTSRP problem. Numerical examples are presented to analyse the performance of the cooperative system designed by the GA‐based JTSRP.

How to improve and regulate coffee bean yield and quality through split fertilization in the whole life cycle of coffee is still unclear and deserves further study. A field experiment of 5-year-old Arabica coffee trees was conducted for 2 consecutive years from 2020 to 2022. The fertilizer (750 kg ha-1 year-1, N-P2O5-K2O:20%-20%-20%) was split in three times at early flowering (FL), the berry expansion (BE), and the berry ripening (BR). Taking equal fertilization throughout the growth cycle (FL250BE250BR250) as the control check, variable fertilizations including FL150BE250BR350, FL150BE350BR250, FL250BE150BR350, FL250BE350BR150, FL350BE150BR250, and FL350BE250BR150. Leaf net photosynthetic rate (Anet), stomatal conductance (gs), transpiration rate (Tr), leaf water use efficiency (LWUE), carboxylation efficiency (CE), partial factor productivity of fertilizer (PFP), bean yield, crop water use efficiency (WUE), bean nutrients, volatile compounds and cup quality, and the correlation of nutrients with volatile compounds and cup quality was evaluated. FL350BE250BR150 had the maximum Anet and gs, followed by FL250BE350BR150. The highest dry bean yield and WUE were obtained from FL250BE350BR150, which increased by 8.86% and 8.47% compared with FL250BE250BR250 in two-year average. The ash, total sugar, fat, protein, caffeine and chlorogenic acid in FL250BE350BR150 were 6.47%, 9.48%, 3.60%, 14.02%, 4.85% and 15.42% higher than FL250BE250BR250. Cluster analysis indicated FL150BE350BR250, FL250BE350BR150, FL350BE150BR250 and FL350BE250BR150 under medium roasted degree increased pyrazines, esters, ketones and furans, FL150BE350BR250 and FL250BE350BR150 under dark roasted degree increased ketones and furans. The aroma, flavor, acidity and overall score of medium roasted coffee were higher than dark roasted coffee, while the body score of dark roasted coffee was higher than medium roasted coffee. The nutrient contents were correlated with the volatile compounds and cup quality. TOPSIS indicated that FL250BE350BR150 was the optimal fertilization mode in the xerothermic regions. The obtained optimum fertilization mode can provide a scientific basis for coffee fertilization optimization and management.

BackgroundIn China, the HIV/AIDS epidemic among men who have sex with men (MSM) has been expanding in recent years. Substance abuse in MSM was not well studied as the independent risk factor for HIV and syphilis infection and other sexually transmitted diseases. The present review aimed to determine the correlation between HIV/Syphilis infections and substance abuse and other sexual risk behaviors among MSM.MethodsWe conducted a comprehensive search of PubMed, Web of Science, Embase, Scopus, Chinese National Knowledge Infrastructure, Chinese Wanfang Data, and VIP Chinese Journal Database for relevant articles of quantitative studies published between 2010 and May 31, 2022. Meta-analysis was performed using R software. Pooled estimated of the association-odds ratio, with 95% confidence intervals were calculated using random-effects models stratified by study design. Q statistics and I2 were used to measure the heterogeneity.ResultsOur meta-analysis included 61,719 Chinese MSM from 52 eligible studies. The pooled HIV prevalence rate among substance-abusing MSM was 10.0% (95% CI = 0.08–0.13). Substance abusers were more likely to have a higher prevalence of HIV (OR = 1.59) and syphilis (OR = 1.48) infections than non-substance abusers. Substance abusers were also more likely to seek sexual partners through the internet or social media applications (OR = 1.63), engage in unprotected anal intercourse (UAI) (OR = 1.69), group sex (OR = 2.78), and engage in commercial intercourse (OR = 2.04) compared to non-users. Regarding testing behaviors, substance abusers had a higher proportion of HIV or STI testing in their lifetime (OR = 1.70) compared with non-substance abusers (p < 0.05). They were also more likely to have had more sexual partners (≥2; OR = 2.31) and more likely to have consumed alcohol (OR = 1.49) in the past 6 months.ConclusionsOur study shows the correlation between substance abuse and HIV/Syphilis infection. Eliminating disparities in HIV/Syphilis infection among substance abusing men who have sex with men (MSM) can be achieved if the Chinese government and public health sectors could provide targeted knowledge popularization and diagnosis interventions among high-risk populations.

With the popularization of logistics technology and the improvement of people’s living standards, the number of chain restaurants with delivery service is increasing continuously due to the convenient service and special discounts. However, the inappropriate management mode and delivery delays often lead to high delivery cost, especially during the peak meal period. Therefore, to solve the problems, two delivery modes, Modern Delivery Mode of Chain Restaurants (MDMCR) and Improved Delivery Mode of Chain Restaurants (IDMCR) were first proposed. IDMCR is an one-stage approach to directly solve the delivery routing problem of multiple branches. Furthermore, we presented an adaptive genetic algorithm for delivery of chain restaurants (AGA-DCR) specifically for IDMCR, which adjusts adaptively the traditional crossover and mutation operations to the fitness of individual and population, therefore, local optimal is avoid. The experiments were conducted with the same dataset to compare different approaches. The results demonstrated that AGA-DCR avoided falling into the local optimal while improved the quality of the solution. Moreover, IDMCR combined with AGA-DCR achieved the best performance, reducing the delivery delay cost by 56.2% compared to MDMCR with GA. Additionally, the optimal delivery routes for chain restaurants were visualized to provide a reference solution for the practical applications.

The Western Branch of the Tanlu fault in Bohai Sea refers to the Western Branch fault of Bohai segment of the Tanlu fault, the formation and evolution of which plays an important role in controlling the distribution of pre Cenozoic strata and the development of the structure of buried hills.Based on the data of 3D seismic, drilling and experimental data, the structural characteristics, genetic evolution model of the Western Branch of the Tanlu fault in Bohai Sea and its control on the formation of buried hills are analyzed.The results show that: ①the Western Branch of Tanlu fault in Bohai Sea is characterized by multi-stage superimposed activities in Indosinian, Yanshanian and Himalayan.The activation of late Himalayan is weak, and it is concealed under Cenozoic sediments.②The Western Branch of the Tanlu fault in Bohai Sea is divided into three segments: north, middle and south by nearly EW trending fault.There are some differences in the structural deformation patterns and strength of each segment in the key geological period.③The Western Branch of the Tanlu fault in Bohai Sea was originated from strike slip transition caused by uneven N-S compression in Indosinian.④Indosinian-Yanshanian strike slip thrust and associated folds in the Western Branch of the Tanlu fault in Bohai Sea are the key factors controlling the distribution of strata buried hills and the formation 19-6 buried hill structures of Bozhong.The research results can provide a basis for oil and gas exploration in Bohai Sea.

The hydrocarbon accumulation pattern of the Mesozoic covered Archean buried hill in the Bohai Oilfield was not clarified before, which restricts the oil and gas exploration progress in this area. In recent years, reservoir development modes and reservoir prediction technologies have been researched after the structural evolution and stratigraphic distribution characteristics of the buried hill in the Bozhong sag were investigated based on new 3D seismic data and a large number of cores and logging data of newly drilling wells. Then, the hydrocarbon accumulation pattern of covered type Archean buried hill was analyzed. Finally, this pattern was applied to guide the oil and gas exploration deployment in Bozhong 13-2 structure, and a significant discovery of Bozhong 13-2 large monoblock volatile buried hill oilfield was realized. And the following research results were obtained. First, the structure in this area mainly experienced multi-period tectonic movements, such as Indosinian, Yanshanian and Himalayan, and it is characterized by compression and thrusting to form a hill during Indosinian-early Yanshanian, extension and inversion transformation during middle Yanshanian, and burial and finalization during Himalayan, forming Bozhong 13-2 Mesozoic covered Archean large buried hill trap. Second, under the effect of Mesozoic cover and the control of multi-stage stress superposition, the reservoir development in this area has the distribution characteristics of “different vertical top, internal lateral continuity”. Third, the fracture prediction technology based on smooth reflection strength filter is developed. And by means of this technology, multi-scale fractured reservoirs inside buried hills can be predicted effectively. Fourth, the hydrocarbon accumulation pattern of “overpressure injection-relay migration” for covered type buried hills is established, which provides a basis for long-distance migration and large-scale accumulation of oil and gas in covered type buried hills. In conclusion, these understandings guide the discovery of Bozhong 13-2 Oilfield, achieve a breakthrough in the oil and exploration of Mesozoic covered buried hill in the Bohai Oilfield and can be used as the reference for the oil and gas exploration in the similar covered type buried hills of the Bohai Bay Basin and other areas.

Abstract Self-direction skill is considered a vital skill for twenty-first-century learners in both the learning context and physical activity context. Analysis skill for self-directed activities requires the students to analyze their own activity data for understanding their status in that activity. It is an important phase that determines whether an appropriate plan can be set or not. This research presents a framework designed to foster students’ analysis skill in self-directed activities, which aims (1) to build a technology-enabled learning system allowing students to practice analyzing data from their own daily contexts, (2) to propose an approach to model student’s analysis skill acquisition level and process, and (3) to provide automated support and feedback for analysis skill development tasks. The analysis module based on the proposed framework was implemented in the GOAL system which synchronized data from learners’ physical and reading activities. A study was conducted with 51 undergraduate students to find reliable indicators for the model to then measure students’ analysis skills. By further analyzing students’ actual usage of the GOAL system, we found the actual activity levels and their preferences regarding analysis varied for the chosen contexts (learning and physical activity). The different context preference groups were almost equal, highlighting the utility of a system that integrates data from multiple contexts. Such a system can potentially respond to students’ individual preferences to execute and acquire self-direction skill.

With the widespread access of flexible loads and renewable energy, the power flow often exceeds the limit of line, resulting in the blockage of distribution network. Virtual power plant (VPP) can not only integrate multiple forms of energy, but also improve the penetration proportion of renewable energy sources. In view of the excellent ability of VPP in power market, a two-stage congestion management (CM) model involving virtual power plant (VPP) with cascade hydro-photovoltaic-pumped storage hybrid generators is established in this paper. The first stage is congestion management of ISO (Independent System Operator), which aims at minimizing congestion cost and is solved by genetic algorithm. The second stage is power correction model of virtual power plant, which is a multi-objective problem considering water and light curtailment, navigation and ecological needs. An improved hybrid non-dominated sorting genetic algorithm-II (HNSGA-II) is proposed to solve the two-stage model. Case studies show that the participation of virtual power plants in congestion management has certain economic value to power system. The joint dispatch of cascade hydro-photovoltaic-pumped storage hybrid generation in the virtual power plant can make flexible decisions according to the needs of energy saving, navigation and ecology. The improved HNSGA-II algorithm is superior to the traditional NSGA-II algorithm in convergence, uniformity and extensity.

Spatial heterogeneity in composition and organisation of the primary cell wall affects the mechanics of cellular morphogenesis. However, directly correlating cell wall composition, organisation and mechanics has been challenging. To overcome this barrier, we applied atomic force microscopy coupled with infrared (AFM-IR) spectroscopy to generate spatially correlated maps of chemical and mechanical properties for paraformaldehyde-fixed, intact Arabidopsis thaliana epidermal cell walls. AFM-IR spectra were deconvoluted by non-negative matrix factorisation (NMF) into a linear combination of IR spectral factors representing sets of chemical groups comprising different cell wall components. This approach enables quantification of chemical composition from IR spectral signatures and visualisation of chemical heterogeneity at nanometer resolution. Cross-correlation analysis of the spatial distribution of NMFs and mechanical properties suggests that the carbohydrate composition of cell wall junctions correlates with increased local stiffness. Together, our work establishes new methodology to use AFM-IR for the mechanochemical analysis of intact plant primary cell walls.

The BZ19-6 deep buried-hill structural belt in the southwest of Bozhong Sag, Bohai Bay Basin, is a newly discovered super-giant oil and gas bearing area. The study on its reservoirs is still in the early stage, and the characteristics and control factors of reservoir development are not understood deeply. In this paper, cores, sidewall cores, rock sections were analyzed and described. Then, based on regional structural setting, mud logging and logging data, the buried-hill reservoirs in this area were analyzed from the aspects of petrological characteristics, reservoir space types and physical properties, the inherent factors influencing the development of the reservoirs were discussed, and distribution laws of the reservoirs were investigated. And the following research results were obtained. First, the deep buried-hill reservoirs of this belt are a pan-buried hill reservoir system composed of the Palaeocene–Eocene Kongdian Fm glutenite in the upper part and the Archean buried-hill metamorphic granite in the lower part. A multi-layer reservoir structure of glutenite pore zone, weathering crust dissolution fracture zone and inner fracture zone is formed. These reservoirs are complex in genesis and diverse in type. Second, the Archean buried-hill metamorphic granite reservoir can be vertically divided into weathering crust, inner fracture zone and tight zone, and it presents the dual characteristics of porous and fractured media. Third, the buried-hill weathering crust is mainly affected by strong dissolution and leaching superimposed with fracturing, forming fractured-porous reservoir space. The reservoir of inner fracture zone is mainly controlled by the superimposition of three-phrase fractures, which forms the main development period of buried-hill fractures since the Yanshanian. Fourth, the glutenite of Kongdian Fm is a typical sieve deposit and it is mainly controlled by the late dissolution. Fifth, migmatization and supercritical fluid cryptoexplosion play a constructive role in the development of the reservoirs. In conclusion, the understanding of buried-hill glutenite and metamorphic reservoir system developed in this belt is conductive to determining the target and direction of next oil and gas exploration in this area. Keywords: Bohai bay basin, Bohai sea area, BZ19-6 deep buried-hill structural belt, Archean, Deep metamorphic granite reservoir, Paleogene, Glutenite reservoir, Dissolution, Structural fracture

User authentication and verification by gait data based on smartphones’ inertial sensors has gradually attracted increasing attention due to their compact size, portability and affordability. However, the existing approaches often require users to walk on a specific road at a normal walking speed to improve recognition accuracy. In order to recognize gaits under unconstrained conditions on where and how users walk, we proposed a Hybrid Deep Learning Network (HDLN), which combined the advantages of a long short-term memory (LSTM) network and a convolutional neural network (CNN) to reliably extract discriminative features from complex smartphone inertial data. The convergence layer of HDLN was optimized through a spatial pyramid pooling and attention mechanism. The former ensured that the gait features were extracted from more dimensions, and the latter ensured that only important gait information was processed while ignoring unimportant data. Furthermore, we developed an APP that can achieve real-time gait recognition. The experimental results showed that HDLN achieved better performance improvements than CNN, LSTM, DeepConvLSTM and CNN+LSTM by 1.9%, 2.8%, 2.0% and 1.3%, respectively. Furthermore, the experimental results indicated our model’s high scalability and strong suitability in real application scenes.

Abstract The aim of this research is to measure self-regulated behavior and identify significant behavioral indicators in computer-assisted language learning courses. The behavioral measures were based on log data from 2454 freshman university students from Art and Science departments for 1 year. These measures reflected the degree of self-regulation, including anti-procrastination, irregularity of study interval, and pacing. Clustering analysis was conducted to identify typical patterns of learning pace, and hierarchical regression analysis was performed to examine significant behavioral indicators in the online course. The results of learning pace clustering analysis revealed that the final course point average in different clusters increased with the number of completed quizzes, and students who had procrastination behavior were more likely to achieve lower final course points. Furthermore, the number of completed quizzes and study interval irregularity were strong predictors of course performance in the regression model. It clearly indicated the importance of self-regulation skill, in particular completion of assigned tasks and regular learning.

Kernel length, kernel width, and kernel thickness are important traits affecting grain yield and product quality. Here, the genetic architecture of the three kernel size traits was dissected in an association panel of 309 maize inbred lines using four statistical methods. Forty-two significant single nucleotide polymorphisms (SNPs; p < 1.72E-05) and 70 genes for the three traits were identified under five environments. One and eight SNPs were co-detected in two environments and by at least two methods, respectively, and they explained 5.87–9.59% of the phenotypic variation. Comparing the transcriptomes of two inbred lines with contrasting seed size, three and eight genes identified in the association panel showed significantly differential expression between the two genotypes at 15 and 39 days after pollination, respectively. Ten and 17 genes identified by a genome-wide association study were significantly differentially expressed between the two development stages in the two genotypes. Combining environment−/method-stable SNPs and differential expression analysis, ribosomal protein L7, jasmonate-regulated gene 21, serine/threonine-protein kinase RUNKEL, AP2-EREBP-transcription factor 16, and Zm00001d035222 (cell wall protein IFF6-like) were important candidate genes for maize kernel size and development.

Malignant gliomas are the most prevalent and deadly primary brain tumors. The life expectancy of people with gliomas only slightly increases through surgical procedures, radiation, and chemotherapy. Magnetic nanocarriers must be developed to enable drug delivery using a magnetic field. A utilized to fabricate holmium ferrite nanoparticles is described herein. β -Cyclodextrin-polyethylene glycol (PEG) conjugate is used as a coat for the holmium ferrite nanoparticles. X-ray diffraction, energy dispersive x-ray spectroscopy, and x-ray photoelectron spectroscopy are all used to study the nanoparticles. This size range of nanoparticles is optimal for efficient drug delivery. The in vitro cytotoxicity of the fabricated nanoparticles was examined using U87MG and LN229 glioma cancer cells. The acridine orange/ethidium bromide and nuclear staining methods examined the morphological changes in the U87MG and LN229 glioma cells. The mode of cell death mechanism was investigated by Annexin V-FITC/PI flow cytometry methods. The possibility for successful SN38 delivery for the treatment of glioma cancer exists with the SN38@HF- β -CD-PEG.

Space-time adaptive processing (STAP) is supposed to be a crucial technique for improving target detection performance in a strong clutter background for airborne phased array radar systems. In this paper, we consider the extremely heterogeneous case, i.e., the number of available training samples is limited to one. The sparse recovery (SR) technique is first utilized to obtaining the independent clutter patches. Contrary to traditional SR STAP which estimates the clutter covariance matrix (CCM) with these clutter patches, the proposed approach will estimate the `clutter ridge' based on linear regression by making use of these clutter patches. With the prior knowledge of number of receiver elements, a more accurate estimation of CCM is obtained. From the simulation results, the proposed approach can achieve a great performance enhancement of clutter suppression with only one training sample compared with conventional SR based STAP algorithms. Even for the cases where amplitude and phase errors are consider, the proposed approach can be superior to traditional SR STAP about 5~10 dB.

Passive multiple-input multiple-output radar is studied for the problem of joint estimation of target location and velocity. A general case is considered, where the signals of opportunity may be non-orthogonal and the clutter-plus-noise may be correlated. The maximum likelihood estimate is provided and the Cramer-Rao bound is derived. The authors show the performance gain obtained from coherent processing and analyse the performance variation induced by the effects of signal non-orthogonality and the correlation of the clutter-plus-noise components.

Carnosic acid (CA) has been reported to exhibit a variety of bioactivities including antioxidation, neuroprotection, and anti-inflammation; however, the impact of CA on subarachnoid hemorrhage (SAH) has never been elucidated. The current study was undertaken to explore the role of CA in early brain injury (EBI) secondary to SAH and the underlying mechanisms. Adult male Sprague-Dawley rats were perforated to mimic a clinical aneurysm with SAH. CA or vehicle was administered intravenously immediately after the SAH occurred. Mortality, SAH grade, neurologic function scores, brain water content, Evans blue extravasation, and the levels of reactive oxygen species (ROS) levels in the ipsilateral cortex were determined 24 h after the SAH occurred. Western blot, immunofluorescence, Fluoro-Jade C (FJC) and TUNEL staining were also performed. Our results showed that CA decreased ROS levels, alleviated brain edema and blood-brain barrier permeability, reduced neuronal cell death, and promoted neurologic function improvement. To probe into the potential mechanisms. We showed that CA increased SIRT1, MnSOD, and Bcl-2 expression, as well as decreased p66shc, Bax, and cleaved caspase-3 expression. Interestingly, sirtinol, a selective inhibitor of SIRT1, abolished the anti-apoptotic effects of CA. Taken together, these data revealed that CA has a neuroprotective role in EBI secondary to SAH. The potential mechanism may involve suppression of neuronal apoptosis through the SIRT1/p66shc signaling pathway. CA may provide a promising therapeutic regimen for management of SAH.

China Rail Express (CRE) is the international container train line that runs between China and Europe. Since the implementation of China’s Belt and Road initiative, CRE has developed rapidly. As most CRE trains travel directly from source to destination without load consolidation, CRE faces issues such as an insufficient cargo supply, a low load factor, and a low profit margin. To address these problems, we analyzed the selection of potential consolidation centers and the optimization of consolidation routes to these centers from the perspective of complex network evolution. First, we constructed rules for generation and evolution of the complex network. Next, we generated logistics connection topology networks for CRE from 2013 to 2017 using those rules. We then optimized the consolidation routes based on the network structures formed from those rules. Chongqing, Xi’an, Chengdu, Zhengzhou, Shenyang, Lanzhou, Urumqi, and Tianjin were selected as potential consolidation centers. We conclude with a sensitivity analyses and a discussion of management implications for CRE.

Self-directed learning (SDL) requires students to take initiative to learn and control their own learning process. Literature highlights the importance of SDL for lifelong learning. Yet, little understanding is known regarding how to support SDL at the school level, specifically for out-of-class learning context. To fill up this gap, this research developed a learning dashboard and integrated SDL process management in GOAL system. It was implemented to provide support for out-of-class online self-directed extensive reading (SDER) at a high school level. A two-group study conducted during a three-week spring vacation found the experimental group (N = 35, with SDL support) achieved significantly more reading outcomes than the control group (N = 12, without SDL support). Detailed GOAL interaction behavior analysis of the experimental group showed that viewing learning dashboard was significantly correlated with reading outcomes as well as interactions related to SDL process management. These findings highlights positive effect of SDL support in GOAL on students' out-of-class SDER outcomes as well as their SDL behaviors. The study provided implications for research related to extensive reading and SDL support for out-of-class learning.

The ERA (E. coli RAS-like protein)-related GTPase (ERG) is a nuclear-encoded GTPase with two conserved domains: a GTPase domain and a K Homology (KH) domain. ERG plays a vital role in early seed development in Antirrhinum majus. However, the mechanism that regulates seed development remains unclear. Blasting the genome sequence revealed two homologies of ERG, AtERG1, and AtERG2 in Arabidopsis. In this study, we found that AtERG2 is localized in the mitochondria and binds mitochondrial 18S RNA. Promoter and transcript analyses indicated that AtERG2 was mainly expressed in the leaf vein, trichome, and ovule. The T-DNA insertion lines of AtERG2 showed silique shortage, early seed abortion, and sporophytic maternal effects (SME), in which some seeds arrested in the zygotic stage at 1.5 days after pollination (DAP) and aborted at 2.0 DAP in aterg2-1 +/−. We further showed that the ovules of these arrested seeds presented unusual tissue degradation inside the embryo sacs. Reactive oxygen species (ROS) accumulated at 1.0 and 1.5 DAP in the arrested seeds, and the transcription of several ROS-responsive genes, WRKY40, ANAC017, and AOX1a, was up-regulated in the aterg2-1 +/− arrested seeds at 1.5 and 2.0 DAP, but not in wild-type (WT) and aterg2-1 +/− developed seeds. The cell death-related gene BAG6 was also transcriptionally activated in aterg2-1 +/− seeds arrested at 2.0 DAP. Additionally, the protein level of mitochondria protein ATPase Subunit 6 was lower in 2-DAP siliques of aterg2-1 +/− than it was in those of WT. These results suggested that AtERG2 promotes early seed development by affecting the maturation of the mitochondria ribosome small subunit and mitochondrial protein translation in Arabidopsis.

For the interconnected power system with large-scale wind power, the problem of the small signal stability has become the bottleneck of restricting the sending-out of wind power as well as the security and stability of the whole power system. Around this issue, this paper establishes a small signal stability region boundary model of the interconnected power system with large-scale wind power based on catastrophe theory, providing a new method for analyzing the small signal stability. Firstly, we analyzed the typical characteristics and the mathematic model of the interconnected power system with wind power and pointed out that conventional methods can’t directly identify the topological properties of small signal stability region boundaries. For this problem, adopting catastrophe theory, we established a small signal stability region boundary model of the interconnected power system with large-scale wind power in two-dimensional power injection space and extended it to multiple dimensions to obtain the boundary model in multidimensional power injection space. Thirdly, we analyzed qualitatively the topological property’s changes of the small signal stability region boundary caused by large-scale wind power integration. Finally, we built simulation models by DIgSILENT/PowerFactory software and the final simulation results verified the correctness and effectiveness of the proposed model.

Graphene has been recently proposed as a promising alternative to support surface plasmons with its superior performances in terahertz and mid-infrared range. Here, we propose a graphene-coated elliptical nanowire (GCENW) structure for subwavelength terahertz waveguiding. The mode properties and their dependence on frequency, nanowire size, permittivity and chemical potential of graphene are studied in detail by using a finite element method, they are also compared with the graphene-coated circular nanowires (GCCNWs). Results showed that the ratio of the long and short axes (b/a) of the elliptical nanowire had significant influence on mode properties, they also showed that a propagation length over 200 μm and a normalized mode area of approximately 10−4~10−3 could be obtained. Increasing b/a could simultaneously achieve both long propagation length and very small full width at half maximum (FWHM) of the focal spots. When b/a = 10, a pair of focal spots about 40 nm could be obtained. Results also showed that the GCENW had a better waveguiding performance when compared with the corresponding GCCNWs. The manipulation of Terahertz (THz) waves at a subwavelength scale using graphene plasmon (GP) may lead to applications in tunable THz components, imaging, and nanophotonics.

Zhengdan958 and Anyu5 are two elite maize hybrids of China, which manifest similar paternal lines (Chang7-2) but different maternal lines (Zheng58 and Ye478). Zhengdan958 has a 10-15% yield advantage over Anyu5. In this study, we applied digital gene expression technology to analyze transcriptomes of mature embryos from the two hybrids and their parents, aimed to investigate molecular mechanism of heterosis and genetic effects of maternal lines. Results showed that 71.66% and 49.70% of differentially expressed genes exhibited non-additive expression in Zhengdan958 and Anyu5, respectively. The number of non-additive genes involved in abiotic and biotic stress responses in Zhengdan958 was higher than that in Anyu5, which was in agreement with their phenotypic performance. Furthermore, common over-dominance and under-dominance genes (137 and 162, respectively) between the two hybrids focused on plant development and abiotic stress response. Zhengdan958 contained 97 maternal expression-level dominance (maternal-ELD) genes, and the number was higher than that of Anyu5 (45). Common up-regulated maternal-ELD genes were significantly enriched in meristem and shoot development while common down-regulated maternal-ELD genes were involved in pyruvate metabolic process, negative regulation of catalytic activity and response to stress. Therefore, non-additive genes mainly contribute to heterosis in Zhengdan958, including many genes for plant development, abiotic and biotic stress responses. Maternal effects may play important roles in maize heterosis.

The signal integrity of the circuit, as one of the important design issues in high-speed digital system, is usually seriously affected by the signal reflection due to impedance mismatch in the DDR3 bus. In this paper, a novel optimization method is proposed to optimize impedance mismatch and reduce the signal refection. Specifically, by applying the via parasitic, an equivalent model of DDR3 high-speed signal transmission, which bases on the match between the on-die-termination (ODT) value of DDR3 and the characteristic impedance of the transmission line, is established. Additionally, an improved particle swarm optimization algorithm with adaptive perturbation is presented to solve the impedance mismatch problem (IPSO-IMp) based on the above model. The algorithm dynamically judges particles’ state and introduces perturbation strategy for local aggregation, from which the local optimum is avoided and the ability of optimization-searching is activated. IPSO-IMp achieves higher accuracy than the standard algorithm, and the speed increases nearly 33% as well. Finally, the simulation results verify that the solution obviously decreases the signal reflection, with the signal transmission quality increasing by 1.3 dB compared with the existing method.

It is of vital importance to exactly estimate the unknown parameters of chaotic systems in chaos control and synchronization. In this paper, we present a method for estimating one-dimensional discrete chaotic system based on mean value method (MVM). It is proposed by exploiting the ergodic and synchronization features of chaos. It can effectively estimate the parameter value, and it is more exact than MVM. Finally, numerical simulations on Chebyshev map and Tent map show that the proposed method has better performance of parameter estimation than MVM.