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In order to improve the surface erosion resistance of titanium alloy substrate and study the effect of Cr based multilayer film on the fatigue mechanical properties of titanium alloy substrate, three kinds of Cr-CrN-Cr-CrAlN multilayer film with different thickness(3.99,6.85,9.62 μm) were deposited on the surface of TC4 titanium alloy by vacuum cathodic arc deposition technology. The axial tensile performance and axial high low cycle fatigue performance of TC4 titanium alloy substrate and the film specimens at room temperature were studied and compared mainly through tensile tests and axial loading fatigue tests. Results showed that the thicknesses of Cr-CrN-Cr-CrAlN multilayer film prepared on the surface of TC4 titanium alloy were approximately 3.99, 6.85 and 9.62 μm, respectively. Moreover, the corresponding hardnesses were 2 455, 3 024 and 3 578 HV, and the adhesion forces of film-substrate were 12.4, 15.2 and 20.1 N, respectively. After coated with multiple layers, the tensile yield strength, tensile strength and elastic modulus of TC4 titanium alloy were improved, while the elongation at break was reduced. The multilayer film with 6.85 μm decreased the axial high cycle fatigue limit of TC4 titanium alloy by 4.15%, and the film had little effect on the high cycle fatigue performance. Besides, the effect of film on the low cycle fatigue performance was significant, with a decrease of approximately 21.04% in fatigue strength corresponding to a lifespan of 50 000 cycles.

This article presents the first meta-analysis on correlations of morphological awareness (MA) with reading-related abilities in deaf and hard-of-hearing (DHH) students (k = 14, N = 556). The results showed high mean correlations of MA with all three reading-related abilities: rs = 0.610, 0.712, and 0.669 (all ps < 0.001), respectively, for word reading, vocabulary knowledge, and reading comprehension. A set of moderator analysis was conducted of language, DHH students' age/reading stage and degree of hearing loss, and task type. The correlation of MA with word reading was significantly stronger in alphabetic than in non-alphabetic languages, and for fluency than accuracy; for vocabulary knowledge, the correlation was significantly stronger for production MA tasks than for judgment tasks; for reading comprehension, derivational MA tasks showed a stronger correlation than those having a mixed focus on inflection and derivation. While no other moderator effects were significant, the correlations for subsets of effect sizes were largely high for a moderator. These findings reaffirmed the importance of morphology in DHH students' reading development. The present synthesis, while evidencing major development of research on the metalinguistic underpinnings of reading in DHH students, also showed that the literature on MA is still very limited.

This article synthesizes the roles of morphology in English reading acquisition and reports a meta-analytic structural equation modeling study (k = 107, N = 21,818) that tested the effects of morphological awareness (MA) on reading comprehension in school-aged readers. Moderator analysis was conducted through a set of subgroup comparisons based on readers' language status (monolingual vs. bilingual), age/grade (lower elementary, upper elementary, vs. middle/high school), and MA task modality (spoken vs. written). MA had significant indirect effects on reading comprehension via both word reading and vocabulary knowledge in the full sample as well as all subgroups. Its direct effect on reading comprehension, controlling for nonverbal reasoning, word reading, and vocabulary knowledge, was also significant in all subgroups except the lower elementary subgroup. Multi-group path analyses showed no significant subgroup difference in the magnitude of the direct effect of MA on reading comprehension for any moderator. However, two notable findings surfaced on the indirect effects of MA on reading comprehension: bilingual readers showed a smaller indirect effect of MA via word reading than did monolinguals; older readers showed a stronger indirect effect via vocabulary knowledge than did younger readers, whereas a converse pattern was found for the indirect effect via word reading. We conclude by pointing out the robust contribution of morphology to English reading comprehension and suggesting a strong meaning focus in morphological instruction, especially for bilingual and older school-aged readers.

This scoping review explores the causal relationship between morphological instruction and reading development in young L2 learners by synthesizing 12 primary studies published between 2004 and 2019 (N = 1,535). These studies focused on reading English as the target language and involved participants between kindergarten and Grade 12 from four countries (China, Egypt, Singapore, and the USA). Findings suggested that (a) morphological instruction led to consistent and positive gains in L2 children's morphological awareness and vocabulary knowledge, and the effect sizes (Cohen's "d"s) ranged from small to large; and (b) the relationship between morphological instruction and other outcomes such as phonological awareness, word reading accuracy, word reading fluency, spelling, and reading comprehension was inconclusive. Notably, transfer effects of L2 English morphological instruction on novel word learning in English or on reading development in an additional language were only examined and observed in four primary studies. Discussion was provided regarding future instructional and research design.

Grammatical and vocabulary knowledge (i.e., breadth and depth) are widely acknowledged as key predictors of reading comprehension in a second language (L2). However, it remains unclear how different aspects of vocabulary depth may independently contribute to L2 reading comprehension and how learners' proficiency may moderate the relative contributions of vocabulary knowledge. Based on the Lexical Quality Hypothesis and the Reading Systems Framework, this study investigated 238 L2 Chinese learners who were college-level students in China, using a set of reading-related tasks. The results showed that (1) vocabulary breadth and grammatical knowledge independently contributed to L2 reading comprehension with grammatical knowledge being a more deciding factor; (2) different aspects of vocabulary depth (i.e., polysemy and synonymy), over and above vocabulary breadth and grammatical knowledge, played an independent role; and (3) more importantly, lower-proficiency learners relied more on vocabulary breadth whereas higher-proficiency learners made more use of vocabulary depth during text-level comprehension.

This study compared how distinct lexical competences, including lexical knowledge as well as processing skills at both word/lexical and sublexical/morphological levels, collectively and relatively predict reading comprehension in adult learners of English as a foreign language (EFL). The participants were 220 Arabic-speaking EFL learners in a Saudi university. A battery of paper- and computer-based tests was administered to measure the participants' lexical competences, reading comprehension ability, and working memory. Hierarchical regression analyses revealed that over and above working memory, both lexical and sublexical knowledge were significant and unique predictors of reading comprehension, and sublexical processing efficiency, as opposed to lexical processing efficiency, predicted reading comprehension significantly. In addition, among the measured lexical competences, lexical knowledge was the strongest predictor, and the two knowledge variables collectively had a far greater influence on reading comprehension than did the two processing efficiency variables. These findings are discussed in light of the lexical basis of text comprehension.

Fundus retinal blood vessel analysis and detection of exudates and bleeding points are important methods for judging the degree of diabetic retinopathy. Aiming at the problems such as poor segmentation effect of bifurcation and end points of microvessels, unclear exudate boundary, difficult segmentation of small and scattered bleeding points, an improved U-shaped network is proposed to extract more rich high-level features by improving the context extraction coding module. And in the feature encoding stage, a hybrid attention mechanism (HAM) is added to highlight the features of microvessels and lesions, and reduce the impact of background and noise. Experimental results show that the segmentation accuracy, sensitivity, specificity and AUC value of the proposed algorithm on the fundus retinal blood vessel segmentation dataset DRIVE are better than U-NET, CE-NET and other existing methods. The sensitivity is increased by 0.0146 compared with CE-Net network. On diabetic retinopathy lesion segmentation dataset DIARETDB1, the segmentation effect of exudates and bleeding points is better than U-NET, CE-NET and other existing methods, which can effectively assist doctors in diagnosis.

This study examined the crosslinguistic sharing of morphological awareness (MA) in biliteracy development. The analysis included 34 correlational studies with 41 independent samples (N = 4,104). Correlational coefficients were meta-analyzed, yielding four main findings: (a) the correlation between first language (L1) and second language (L2) MA was small (r = 0.30); (b) the interlingual correlations between L1 MA and L2 word decoding and between L1 MA and L2 reading comprehension were both small (r = 0.35, 0.39, respectively); (c) the intralingual correlations between L2 MA and L2 word decoding and between L2 MA and L2 reading comprehension were both moderate (r = 0.46, 0.52, respectively); and (d) MA measurement type and age were significant moderators. Our review suggests that there is a need for future research to align the definition and measurement of MA.

The authors examined the complexity of the simple view of reading, focusing on morphological decoding fluency in fourth-grade readers of English in Singapore. The participants were three groups of students who all learned to become bilingual and biliterate in the English language (EL) and their respective ethnic language in school but differed in the home language they used. The first group was ethnic Chinese students who used English as the dominant home language (Chinese EL1); the other two groups were ethnic Chinese and Malay students whose dominant home language was not English but Chinese (Chinese EL2) and Malay (Malay EL2), respectively. The measures included pseudoword decoding (phonemic decoding), timed decoding of derivational words (morphological decoding fluency), oral vocabulary, and passage comprehension. Path analysis showed that oral vocabulary significantly predicted reading comprehension across all three groups, yet a significant effect of morphological decoding fluency surfaced in the Chinese EL1 and Malay EL2 groups but not the Chinese EL2 group. Multigroup path analysis and commonality analysis further confirmed that morphological decoding played a larger role in the Chinese EL1 and Malay EL2 groups. These findings are discussed in light of the joint influence of target-language experience and cross-linguistic influence on second-language or bilingual reading development.

The research objectives, modeling, and tensile test strategy of fiber-reinforced asphalt concrete.