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Data analysis knowledge is an indispensable aspect of teachers’ data literacy, which not only has a profound impact on the cultivation of students’ data analysis ability, but also is related to reasonable decision-makings in education. Based on the analyses of teachers’ data literacy and data analysis ability, this study constructed a cognitive model of teachers’ data analysis knowledge and developed an instrument for measuring teachers’ data analysis knowledge. Meanwhile, from a data-driven approach, G-DINA package in software R was used to select a well-fitted GDM Model from a series of cognitive diagnostic models such as DINA, DINO, RRUM, ACDM, LLM, G-DINA and Mixed Model for parameter assessment of cognitive diagnosis, and the reliability and model fit of the instrument were analyzed afterwards. By analyzing the pre-service dataset of 531 Chinese teachers, it made the conclusion that teachers with the same attributes have differences in attribute mastery and knowledge status, and teachers show a main learning path of A8 → A4 → A1 → A3 → A7 → A5 → A2 → A6 in terms of data analysis knowledge. It provided a systematic case study for the assessment of pre-service teachers’ knowledge of data analysis, and also provides a new perspective in assessing other knowledges and abilities.

Delamination damages limit the application potential of Fiber metal laminates, hence improving the interlaminar mechanical properties has always been a research focus and challenge in this field. The toughening effect of two fillers, i.e., nano-aramid fibers (ANFs) and short-aramid fibers (ASFs), which are used at the interface of glass fiber-aluminum laminates, have been investigated. Chemical pretreatments of aluminum alloy surface were conducted to ensure the better adherence between the fiber composites and metal sheets. Results revealed that Mode-I and Mode-II fracture toughness of the laminates could be simultaneously improved when using the two fillers at the interface of glass fiber-aluminum laminates. Attributed to the better dispersion of ANFs in epoxy matrix, the toughening performance of ANFs is better than that of ASFs in this case. The mechanism of interlaminar toughening was revealed with electron microscopic observation of fracture morphology. Meanwhile, the finite element analysis based on bilinear cohesive zone model was adopted to predict the increased interlaminar tensile and shear strength.

Initiated by the Program for International Student Assessment (PISA), Mathematical Key Competencies (MKCs), which integrate into the process of solving situational problems, becomes a typical example of Mathematical Key Competencies assessment. Cognitive Diagnostic Assessment, as a new generation of measurement theory, integrates the measurement objectives into the cognitive process model via cognitive analysis, and helps increase understanding of students’ mastery over fine-grained knowledge points. This paper analyzed 12 PISA test items and calibrated their attributes, thus forming a cognitive model based on six PISA’s MKCs, which were namely Mathematical Abstraction, Logical Reasoning, Intuitive Imagination, Mathematical Modeling, Mathematical Operation and Data Analysis. Through the comparison of models fit for DINA, DINO, RRUM, ACDM, GDM, LCDM, LLM, G-DINA and Mixed Model, the LCDM with a good model fit was selected to analyze the data of 19, 454 students in eight countries, and comparisons of the six MKCs among these countries were obtained. Through analyzing the knowledge states, combing the prerequisite relationships between the attributes, and exploring the learning trajectories of students’ MKCs in different countries, we found that the students’ performance in China was the best among all countries for each of the six MKCs. In all other countries, the students’ performance in Logical Reasoning and Intuitive Imagination were weaker than the other attributes. An analysis of learning trajectories found that Russia, Singapore, Australia and Finland had very similar main learning trajectories (highlighted in red), and the main learning trajectories of Russia and Singapore are the same; however, there exist distinct differences in learning trajectories between China and the United States, where the learning trajectories in China is complicated with varied branches, while the ones in the United States is relatively simple with fewer branches.

Non-ST-segment-elevation acute coronary syndrome (NSTE-ACS) patients with normal left ventricular (LV) ejection fraction (LVEF) and wall motion require a non-invasive tool to detect LV risk areas. This study utilized non-invasive LV pressure–strain loops to evaluate territorial myocardial work efficiency (WE) for identifying obstructive coronary artery stenosis, in patients with non-obstructive or obstructive coronary artery stenosis NSTE-ACS, the latter with or without occlusion. Global and territorial longitudinal strain (LS) analyses were performed via speckle-tracking imaging before coronary angiography. LV pressure–strain loops estimated global and territorial myocardial work index (MWI), constructive work (CW), wasted work (WW), and WE. Receiver operating characteristic curve analysis was used to determine the optimal cutoff value of independent parameters to detect obstructive coronary artery stenosis. Compared with non-obstructive, obstructive coronary artery stenosis showed significantly lower global and territorial LS, MWI, CW, and WE, and higher WW. Territorial LS, MWI, CW, and WE were significantly worse in territories of coronary occlusion. Territorial WE was the best parameter for predicting obstructive coronary artery stenosis (AUC 0.80, cutoff

The present study investigated the changes of biventricular mechanics at rest and during exercise and examined the association between exercise capacity and biventricular mechanics and functional reserve in nonobstructive hypertrophic cardiomyopathy (NHCM) patients. A total of 50 NHCM patients and 25 controls were consecutively recruited for this study. Using echocardiography and two-dimensional speckle-tracking imaging, an experienced echocardiographer determined the following indices: RV free wall longitudinal strain (RVFWLS), LV global longitudinal strain (LVGLS), strain rate (SR), and functional reserve of strain values. We also investigated the relationships between biventricular mechanics and exercise capacity using metabolic equivalents (METs). NHCM patients had lower RVFWLS, LVGLS, systolic SR, early diastolic SR, and systolic and diastolic reserve during exercise compared to controls. An association of biventricular mechanics (LVGLS, RVFWLS) with exercise capacity at rest and during exercise was established. Multivariable logistic regression revealed that RVFWLS and LVE/e' during exercise (RVFWLS-exe, E/e'-exe) were independent predictors of exercise intolerance. Receiver operating characteristic curve analysis indicated that LVE/e'-exe had a higher area under the curve for predicting exercise intolerance in NHCM patients. In hierarchical analysis, RVFWLS-exe provided an incremental predictive value of exercise intolerance over LVGLS during exercise (LVGLS-exe) and LVE/e'-exe. LVE/e'-exe also changed incrementally compared to LVGLS-exe and RVFWLS-exe. NHCM patients have decreased biventricular mechanics at rest and during exercise and impaired biventricular functional reserve, and biventricular mechanics are associated with functional capacity. We propose that simultaneous evaluation of biventricular function should provide incremental predictive value for exercise intolerance.

Pulmonary arterial hypertension (PAH) is more prevalent in females. Paradoxically, female patients have better right ventricular (RV) function and higher survival rates than males. However, the effects of 17β-estradiol (E2) on RV function in PAH has not been studied. Twenty-four male rats were exposed to monocrotaline (MCT) to induce experimental PAH, while treated with E2 or vehicle respectively. Together with eight control rats, thirty-two rats were examined by echocardiography 4 weeks after drug administration. Echocardiographic measurement of RV function included: tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), RV fractional area change (RVFAC) and tricuspid annular systolic velocity (s′). RV free wall longitudinal strain (RVLSFW) and RV longitudinal shortening fraction (RVLSF) were also used to quantify RV function. RV morphology was determined by echocardiographic and histological analysis. TAPSE, RVFAC and s′ were reduced, and RIMP was elevated in the MCT-treated group and vehicle-treated group, when compared with control group (P

The aim of this paper is to study anchor handling vessel (AHV) thrust capacity during anchor deployment, especially in a deep water situation when high external forces are expected. The focus is on obtaining realistic external forces and evaluating the positioning capability of an AHV. Wind, wave and current loads on the AHV are considered. Current load on the mooring line, which is usually excluded in practice, is included in the model as well. The thrust utilisation plot, a concept widely used in the Dynamic Positioning system, is proposed to illustrate the positioning capability of an AHV. The Bourbon Dolphin accident was investigated as a case study using the proposed model and methodology. First, load analysis was performed. The results indicated the importance of applying a reasonable current profile and taking the mooring line effect into account. Then, thrust utilisation plots for normal and accident conditions were compared. The comparison showed that the Bourbon Dolphin might have been in the most unfavourable weather direction in terms of position capability during the accident event. Finally, the effect of mooring line configuration was studied. The results signified that a very long mooring line might challenge the propeller thrust capacity and the propeller thrust loss due to lateral thrust usage needs to be considered. Such an analysis and documentation prior to the commencement of the operation can be used for defining vessel specific limitations and selecting the proper vessel for a specific task.

A novel antibiotic 210-A, named as (6S,8aS,9S,11S,12aR)-6-hydroxy-9,10-dimethyldecahydrobenzo[d]azecine-2,4,12(3H)-trione, was isolated from the fermentation broth of Streptomyces noursei Da07210, its structure was unambiguously established by spectral analyses and chemical comparison with related cycloheximide. Experiments demonstrated that 210-A bore strong activity against Fusarium oxysporum f. sp. cubense race four (Foc race four), which also showed antitumor activity against SMMC-7721 human hepatocarcinoma cells and S180 murine sarcoma, and the IC(50) values were 0.77 and 0.74 microg/ml, respectively.

Strain AM105 was separated from mangrove sediment in the South China Sea in this research. The morphological and genomic data showed that the strain merits description as a novel species, proposed as Micromonospora rifamycinica. From the acetate ethyl extract of its fermentation broth, two antibiotics against Gram-positive bacteria (including MRSA), rifamycin S and its geometric isomer were isolated. Their structures were elucidated on the basis of spectroscopic analyzes. (1)H and (13)C NMR data of the isomer of rifamycin S were first described in this paper.