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The plant leaf veins coupling feature representation and measurement method based on DeepLabV3+ is proposed to solve problems of slow segmentation, partial occlusion of leaf veins, and low measurement accuracy of leaf veins parameters. Firstly, to solve the problem of slow segmentation, the lightweight MobileNetV2 is selected as the extraction network for DeepLabV3+. On this basis, the Convex Hull-Scan method is applied to repair leaf veins. Subsequently, a refinement algorithm, Floodfill MorphologyEx Medianblur Morphological Skeleton (F-3MS), is proposed, reducing the burr phenomenon of leaf veins’ skeleton lines. Finally, leaf veins’ related parameters are measured. In this study, mean intersection over union (MIoU) and mean pixel accuracy (mPA) reach 81.50% and 92.89%, respectively, and the average segmentation speed reaches 9.81 frames per second. Furthermore, the network model parameters are compressed by 89.375%, down to 5.813M. Meanwhile, leaf veins’ length and width are measured, yielding an accuracy of 96.3642% and 96.1358%, respectively.

Ol Doinyo Lengai (ODL, Tanzania, East African Rift) is the only known volcano currently erupting carbonatite on Earth with 30 yr. cycles alternating between quiescent carbonatite effusion and explosive, compositionally-zoned silicate eruptions. We performed isothermal crystallization and thermal gradient experiments involving ODL nephelinite, Na2CO3 and H2O to understand magmatic differentiation in this system using SEM-EDS x-ray analysis, x-ray tomography, SIMS and LA-ICPMS to characterize samples. Isothermal crystallization experiments document that hydrous liquids coexist with nepheline+feldspar; as peralkalinity increases, temperatures decrease. Presence of Na2CO3 increases the solubility of water in the liquid. Experiments placing nephelinite with H2O+ Na2CO3 in a 1,000–350°C thermal gradient show that rapid reaction occurs, resulting in virtually melt-free mineral aggregates having mineral layering reflecting systematic differentiation throughout the capsule. Both types of experiments argue that a continuous interconnected melt exists over a large temperature range in alkalic magmatic systems allowing for differentiation in a reactive mush zone process. Liquid compositions change from carbonate-water bearing nephelinites at high temperature down to hydrous carbonate silicate liquids at

Abstract We explore the behaviors of the holographic entanglement entropy (HEE) in holographic superconductor models with logarithmic nonlinear electrodynamics (LNE) both in AdS soliton and in AdS black hole backgrounds. We observe that the slope of the HEE at the phase transition point behaves discontinuously for different LNE parameters b and geometry parameters $$\ell $$ ℓ , which may be a quite general feature for the second order phase transition. Moreover, at the critical point, the stronger nonlinearity of the LNE gives rise to the smaller HEE in metal/superconductor while leaves the HEE in insulator/superconductor model as is. Interestingly, the behavior of the HEE also implies a “confinement/deconfinement” phase transition in the insulator/superconductor model, and the critical width of the phase transition depends on the chemical potential and the strength of the LNE.

This article proposes a model-based method for the detection and phase location of interturn short fault (ISF) in the permanent magnet synchronous generator (PMSG). The simplified mathematical model of PMSG with ISF on dq-axis is established to analyze the fault signature. The current residuals are accurately estimated through Luenberger observer based on the expanded mathematical model of PMSG. In current residuals, the second harmonics are extracted using negative sequence park transform and angular integral filtering to construct the fault detection index. In addition, the unbalance characteristics of three-phase current after ISF can reflect the location of the fault phase, based on which the location indexes are defined. Simulation results for various operating and fault severity conditions primarily validate the effectiveness and robustness of diagnosis method in this paper.

Proteus mirabilis and Pseudomonas aeruginosa are common pathogens that often form biofilms together in catheter-associated urinary tract infections (CAUTI). However, the interactions between these two species in biofilms are largely unknown. Proteus mirabilis induces ureolytic biomineralization that substantially modifies key biofilm properties including morphology, persistence and recalcitrance to antimicrobial therapy. These processes are well known to complicate CAUTI, but the consequences for colonization and persistence of P. mirabilis in polymicrobial biofilms have not been explored. Here, we characterized the role of biomineralization in regulating the development of P. mirabilis and P. aeruginosa dual-species biofilms. Time-series observations revealed that the dominance of P. mirabilis was synchronized with mineral formation in the biofilm. After 24 h of development, the dual-species biofilm was dominated by P. mirabilis, and the distribution of P. mirabilis biomass was strongly correlated with the mineral fraction of the biofilm. Conversely, dual-species growth without biomineralization yielded strikingly different patterns in the biofilm, with P. aeruginosa dominating the biofilm biomass. These results show that biomineralization is responsible for the increased success of P. mirabilis in the polymicrobial biofilm. Since biofilm biomineralization commonly occurs in diverse clinical, natural and engineered systems, these findings imply that biomineralization could broadly influence the microbial ecology of multispecies biofilms. [ABSTRACT FROM AUTHOR]

Microbial biofilms and mineral precipitation commonly co-occur in engineered water systems, such as cooling towers and water purification systems, and both decrease process performance. Microbial biofilms are extremely challenging to control and eradicate. We previously showed that in situ biomineralization and the precipitation and deposition of abiotic particles occur simultaneously in biofilms under oversaturated conditions. Both processes could potentially alter the essential properties of biofilms, including susceptibility to biocides. However, the specific interactions between mineral formation and biofilm processes remain poorly understood. Here we show that the susceptibility of biofilms to chlorination depends specifically on internal transport processes mediated by biomineralization and the accumulation of abiotic mineral deposits. Using injections of the fluorescent tracer Cy5, we show that Pseudomonas aeruginosa biofilms are more permeable to solutes after in situ calcite biomineralization and are less permeable after the deposition of abiotically precipitated calcite particles. We further show that biofilms are more susceptible to chlorine killing after biomineralization and less susceptible after particle deposition. Based on these observations, we found a strong correlation between enhanced solute transport and chlorine killing in biofilms, indicating that biomineralization and particle deposition regulate biofilm susceptibility by altering biocide penetration into the biofilm. The distinct effects of in situ biomineralization and particle deposition on biocide killing highlight the importance of understanding the mechanisms and patterns of biomineralization and scale formation to achieve successful biofilm control. [ABSTRACT FROM AUTHOR]

This study explores the paleoclimate changes around the 4 ka BP period in the central Qaidam Basin (QB), assessing the differences in spectral characteristics and organic composition of salt lake sediments under different climate change conditions. Sediment samples (10-m-depth profile) were collected from the middle of dry salt flats in East Taijinar Lake (China). Sediment organic matter (SOM) was assessed by Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS). Results showed a significant difference in the TOC content of sediments with different lithological characteristics. A lower TOC content in salt-bearing strata was attributed to the extreme sedimentary environment with minimal exogenous inputs. FTIR spectroscopy revealed that the SOM in sediments included aliphatic C, ketones and alcohols. Sediments of salt-bearing strata generally exhibited a rise in the content of ketone C=O groups and a decrease in aliphatic C, with an equal content of alcohols compared with silty sand. Therefore, exogenous OM and the content of TOC in silty sand strata are higher than in salt-bearing strata, indicating that the paleoclimate became warmer and wetter after 4 ka BP. GC-MS analysis showed a significant difference between the phenol and aldehyde content in different strata, further indicating that the paleoclimate changed from dry to relatively warm around 4 ka BP. Seven organic compound types were identified in SOM, including aldehydes, hydrocarbons, phenols, esters, ketones, alcohols, and furans. Different strata exhibited different distributions of organic compounds, with particularly high concentrations of aldehydes in salt-bearing strata and phenols in silty sand. Correlation analysis was performed between detrital minerals and OM types in all samples. Results showed a strong positive correlation between detrital minerals and phenols and a strong negative correlation between detrital minerals and aldehydes, with a negative correlation also identified between detrital minerals and ketones. Overall, the reduction in volatile organic compounds demonstrates that the paleoclimate changed from cooler and dry to wet and warm around the 4 ka BP period in the central QB, with the carbon preference index and n-alkane values further demonstrating these results. This study also confirms the importance of volatile organic compound monitoring to assess paleoclimate changes.

Lithium ore deposits are divided into pegmatite and brine deposits. The Puna Plateau and the Qinghai–Tibetan Plateau (QTP) are home to the most abundant brine lithium deposits worldwide. Very few studies have investigated the chronology of brine lithium deposits. This paper reports the Optically Stimulated Luminescence (OSL) dating measurements for typical brine lithium deposits at QTP, including East Taijnar Salt Lake, West Taijnar Salt Lake, and Yiliping Salt Lake in the central Qaidam Basin. Combining the results of OSL dating with previous studies and mineral composition obtained by X-ray diffraction analysis (XRD), this study summarizes the age and characteristics of the climatic environment during the formation of brine lithium deposits in the Qaidam Basin. The main results are: 1) Brine lithium deposits in the Qaidam Basin began to form since 40 ka. Brine lithium deposits in South America formed during the middle Pleistocene and late Pleistocene, and are older than the deposits in the Qaidam Basin. The lithium deposits of Tibet formed around 4 ka, are the youngest. 2) The climate in East Taijnar Salt Lake and West Taijnar Salt Lake was extremely cold and dry during 27–4.6 ka, with a relatively humid climatic condition at ∼10 ka. After 4.6 ka, the environment was comparatively more humid around both lakes. Yiliping Salt Lake had a dry climate since 38.09 ka, and the climate in the Three Lakes area is mainly controlled by the westerlies in the Holocene; and 3) East Taijnar Salt Lake, West Taijnar Salt Lake and Yiliping Salt Lake were located in the same secondary basin during the late Pleistocene. However, tectonic activity around 40 ka led to the evolution of Yiliping Salt Lake into an independent basin. East Taijnar Salt Lake and West Taijnar Salt Lake separated around 27 ka, and then deposited the lower salt layers until the Holocene. The substantial amount of detrital minerals that the Nalinggele River brought during the Holocene led to a brief desalination of East Taijnar Salt Lake. The upper salt layer was deposited in East Taijnar Salt Lake and West Taijnar Salt Lake during this period due to the extremely dry climate.

Abstract Background Sarocladium brachiariae is a newly identified endophytic fungus isolated from Brachiaria brizantha. A previous study indicated that S. brachiariae had antifungal activity; however, limited genomic information restrains further study. Therefore, we sequenced the genome of S. brachiariae and compared it with the genome of S. oryzae to identify differences between a Sarocladium plant pathogen and an endophyte. Results In this study, we reported a gapless genome sequence of a newly identified endophytic fungus Sarocladium brachiariae isolated from Brachiaria brizantha. The genome of S. brachiariae is 31.86 Mb, with a contig N50 of 3.27 Mb and 9903 protein coding genes. Phylogenomic analysis based on single copy orthologous genes provided insights into the evolutionary relationships of S. brachiariae and its closest species was identified as S. oryzae. Comparative genomics analysis revealed that S. brachiaria has 14.9% more plant cell wall degradation related CAZymes to S. oryzae, and 33.3% more fungal cell wall degradation related CAZymes, which could explain the antifungal activity of S. brachiaria. Based on Antibiotics & Secondary Metabolite Analysis Shell (antiSMASH) analysis, we identified a contact helvolic acid biosynthetic gene cluster (BGC) for the first time in S. oryzae. However, S. brachiaria had seven fewer terpene gene clusters, including helvolic acid BGC, compared with S. oryzae and this may be associated with adaptation to an endophytic lifestyle. Synteny analysis of polyketide synthases (PKS), non-ribosomal peptide synthetases (NRPS), and hybrid (PKS-NRPS) gene clusters between S. brachiariae and S. oryzae revealed that just 37.5% of tested clusters have good synteny, while 63.5% have no or poor synteny. This indicated that the S. brachiariae could potentially synthesize a variety of unknown-function secondary metabolites, which may play an important role in adaptation to its endophytic lifestyle and antifungal activity. Conclusions The data provided a better understanding of the Sarocladium brachiariae genome. Further comparative genomic analysis provided insight into the genomic basis of its endophytic lifestyle and antifungal activity.

A knowledge graph can structure heterogeneous knowledge in the field of power faults, construct the correlation between different pieces of knowledge, and solve the diversification, complexity, and island of fault data. There are many kinds of entities in power fault defect text, the relationship between entities is complex, and the data are often mixed with noise. It is necessary to research how to effectively mine the target data and separate the salient knowledge from the noise. Moreover, the traditional entity and relationship extraction methods used in the construction of a power fault knowledge graph cannot fully understand the text semantics, and the response accuracy is low. The Log system usually contains all kinds of information related to faults and a log analysis helps us collect fault information and perform association analysis. Therefore, a Bidirectional Sliced GRU with Gated Attention mechanism (BiSGRU-GA) model is proposed to detect the anomalous logs in the power system, this enriches the fault knowledge base and provides a good data resource for the construction of the knowledge graph. A new Bidirectional GRU with Gated Attention mechanism and Conditional Random Fields and a BERT input layer (BBiGRU-GA-CRF) model is proposed by introducing a BERT layer and Attention Mechanism into the Bidirectional GRU (BiGRU) model to more fully understand the context information of fault sentences and improve the accuracy of entity recognition of fault sentences. Aiming to solve the problems of large calculation cost and propagation error which occur in the traditional relationship extraction model, an improved Bidirectional Gated Recurrent Unit neural network with fewer parameters and the Gated Attention Mechanism (BiGRU-GA) model is proposed. This new model introduces an improved Gated Attention Mechanism to achieve better effects in relationship extraction. Compared with Bidirectional Long Short-Term Memory with Attention Mechanism (BiLSTM-Attention), the accuracy, recall, and F-measure of the model were improved by 1.79%, 13.83%, and 0.30% respectively, and the time cost is reduced by about 16%. The experimental results show that the BiGRU-GA model can capture local features, reduce the training time cost, and improve the model recognition effect.

Microbially catalyzed precipitation of carbonate minerals is an important process in diverse biological, geological, and engineered systems. However, the processes that regulate carbonate biomineralization and their impacts on biofilms are largely unexplored, mainly because of the inability of current methods to directly observe biomineralization within biofilms. Here, we present a method for in situ, real-time imaging of biomineralization in biofilms and use it to show that Pseudomonas aeruginosa biofilms produce morphologically distinct carbonate deposits that substantially modify biofilm structures. The patterns of carbonate biomineralization produced in situ were substantially different from those caused by accumulation of particles produced by abiotic precipitation. Contrary to the common expectation that mineral precipitation should occur at the biofilm surface, we found that biomineralization started at the base of the biofilm. The carbonate deposits grew over time, detaching biofilm-resident cells and deforming the biofilm morphology. These findings indicate that biomineralization is a general regulator of biofilm architecture and properties. [ABSTRACT FROM AUTHOR]

Abstract We probe the $$\kappa $$ κ -deformation of spacetime using a two-level atom as a detector coupled to a $$\kappa $$ κ -deformed massless scalar field which is invariant under a $$\kappa $$ κ -Poincaré algebra and written in commutative spacetime. To address the quantum bound to the estimability of the deformation parameter $$\kappa $$ κ , we perform measurements on the two-level detector and maximize the value of quantum Fisher information over all possible detector preparations. We prove that the population measurement is the optimal measurement in the estimation of the deformation parameter $$\kappa $$ κ . In particular, we show that the relativistic motion of the detector affects the precision in the estimation of the parameter $$\kappa $$ κ , which can effectively improve this precision comparing to that of the static detector case by many orders of magnitude.

Using density functional theory calculations, we compute the edge energies and stresses for edges of SiC and BN nanoribbons, and the boundary energies and stresses for domain boundaries of graphene-BN superlattices. SiC and BN armchair nanoribbons show pronounced edge relaxations, which obliterate the threefold oscillatory behavior of the edge stress reported for graphene. Our calculations show small boundary stresses in graphene-BN superlattices, suggesting that such domain boundaries will not experience severe deformation. We have also found that the C-terminated and Si-terminated zigzag edges in SiC nanoribbons have different compressive stresses which results in different rippling behavior of these edges. [ABSTRACT FROM AUTHOR]

This study examines presentations of the distributive property (DP) in two widely used U.S. elementary text series and one main Chinese text series along three dimensions: problem contexts, typical problem types within each problem context, and variability in using the DP. In general, the two U.S. texts were found to resemble each other but to differ considerably from the Chinese text series. Both U.S. texts are computation-dominated, presenting various strategies centering on “breaking apart a factor to perform multiplication.” These strategies limit the use of the DP mainly with whole numbers and in a regular direction. The underlying principle of these strategies is seldom made explicit. In contrast, the Chinese text approaches focus on the underlying principle and are well aligned with cognitive research suggestions. Multiple-step word problems with particular structures are used in a systematic and hierarchic manner across grades to help students learn and transfer the DP. The Chinese texts also tend to ask students to “compute in convenient ways” involving various numbers (e.g., whole numbers, decimals, fractions, and percents) and using the DP in both regular and opposite directions. The introduction of repeated variables is a timely application of the DP, which provides an entry to algebra (e.g., expressions and equations with repeated variables). The Chinese approaches (e.g., contextual interferences, spaced practice, and encoding variability) suggest alternative insights into developing U.S. students' understanding of the DP and readying them for algebra. [ABSTRACT FROM AUTHOR]

Hydraulic conductivity identification remains a challenging inverse problem in ground water modeling because of the inherent nonuniqueness and lack of flexibility in parameterization methods. This study introduces maximum weighted log-likelihood estimation (MWLLE) along with multiple generalized parameterization (GP) methods to identify hydraulic conductivity and to address nonuniqueness and inflexibility problems in parameterization. A scaling factor for information criteria is suggested to obtain reasonable weights of parameterization methods for the MWLLE and model averaging method. The scaling factor is a statistical parameter relating to a desired significance level in Occam’s window and the variance of the chi-squares distribution of the fitting error. Through model averaging with multiple GP methods, the conditional estimate of hydraulic conductivity and its total conditional covariances are calculated. A numerical example illustrates the issue arising from Occam’s window in estimating model weights and shows the usefulness of the scaling factor to obtain reasonable model weights. Moreover, the numerical example demonstrates the advantage of using multiple GP methods over the zonation and interpolation methods because GP provides better models in the model averaging method. The methodology is applied to the Alamitos Gap area, California, to identify the hydraulic conductivity field. The results show that the use of the scaling factor is necessary in order to incorporate good parameterization methods and to avoid a dominant parameterization method. [ABSTRACT FROM AUTHOR]

The authors examined the extent to which teacher interventions focused on students' mathematical thinking in naturalistic cooperative-learning mathematics classroom settings. The authors also observed 6 videotapes about the same teaching content using similar curriculum from 2 states. They created 2 instruments for coding the quality of teacher intervention length, choice and frequency, and intervention. The results show the differences of teacher interventions to improve students' cognitive performance. The authors explained how to balance peer resource and students' independent thinking and how to use peer resource to improve students' thinking. Finally, the authors suggest detailed techniques to address students' thinking, such as identify, diversify, and deepen their thinking. [ABSTRACT FROM AUTHOR]

A novel neural network sliding mode control based on multicommunity bidirectional drive collaborative search algorithm (M-CBDCS) is proposed to design a flight controller for performing the attitude tracking control of a quad tilt rotors aircraft (QTRA). Firstly, the attitude dynamic model of the QTRA concerning propeller tension, channel arm, and moment of inertia is formulated, and the equivalent sliding mode control law is stated. Secondly, an adaptive control algorithm is presented to eliminate the approximation error, where a radial basis function (RBF) neural network is used to online regulate the equivalent sliding mode control law, and the novel M-CBDCS algorithm is developed to uniformly update the unknown neural network weights and essential model parameters adaptively. The nonlinear approximation error is obtained and serves as a novel leakage term in the adaptations to guarantee the sliding surface convergence and eliminate the chattering phenomenon, which benefit the overall attitude control performance for QTRA. Finally, the appropriate comparisons among the novel adaptive neural network sliding mode control, the classical neural network sliding mode control, and the dynamic inverse PID control are examined, and comparative simulations are included to verify the efficacy of the proposed control method.

This study examined students' conceptions about the equal sign in light of historical findings with an international comparison group. Textbooks for preparation of students as mathematics teachers were examined. Participants were sixth-grade students from the USA (n= 105) and China (n= 145). About 98% of the Chinese children correctly answered all items by providing conceptually accurate explanations, but only 28% of the U.S. sample did. Textbooks for education majors who would teach in the USA rarely discussed the equal sign as equivalence while the Chinese texts introduced the "equal sign" in a context of relationships and discussed it as "balance," "sameness," or "equivalence." [ABSTRACT FROM AUTHOR]

The hit probability model is an essential performance measure for anti-air missiles, aircraft, and guided targets in different combat situations and environments. A combination of analytical and numerical fitting methods is proposed to meet the requirements of war game systems including being real-time and accurate. In this approach, a dynamically corrected hit probability model is obtained for the anti-air missiles for which the corrections are made on the distance, speed, and maneuverability correction for the aircraft target. With this method, corrections are also made on the penetrating altitude of the aircraft and guided targets, countering azimuth angle for the guided targets, and terminal maneuverability and echo or infrared signal characteristics correction for the guided targets. After that, war game case analyses show that the proposed hit probability correction method are successfully operated in real-time with a model accuracy which is 6% higher than that of existing models. [ABSTRACT FROM AUTHOR]

The article reviews relevant studies on the effect of class size reduction on student achievement, including its possible effects on classroom instruction and classroom management practices of East Asian teachers. It shows that different cultures have different values for good students and good lessons. Thus, the article believes that it is necessary to ensure that "quality changes" occur in classroom teaching and learning.

The reaction between the ligand N-(2-carboxy­benzometh­yl)-β-alanine (H2cbal), obtained by reducing the Schiff base N-(2-carboxy­benzoimine)-β-alanine, and copper(II) perchlorate afforded a copper(II) complex, {[Cu2(C11H11NO4)2(CH3CN)2](ClO4)2·2CH3CN} n, with an extended three-dimensional framework. The copper(II) ions are in a distorted square-pyramidal geometry in an O4N coordination environment. There is a centre of inversion at the mid-point of the Cu⋯Cu vector. [ABSTRACT FROM AUTHOR]