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Background: Fracture healing complications remain a major problem in trauma monitoring. An open wedge osteotomy of the distal radius provides a unique way of evaluating fracture healing. Since the introduction of cone-beam computed tomography (CBCT) at our institution, it has become the method of choice for assessing hand and wrist bones. To date, CT volumetry has been validated for multidetector CT (MDCT) but not for CBCT. Purpose: To assess osteotomy healing using CBCT volumetry and to evaluate two different segmentation techniques. Material and Methods: A total of 36 patients were surgically treated for malunited distal radius fractures with open-wedge osteotomy either leaving the void empty (open wedge empty [OWE]) or filled with bone graft substitutes (BGS). They were scanned using CBCT and MDCT postoperatively and after 3, 6, and 12 months. Segmentation was performed both manually and semi-automatically for volumetric measurement. Inter- and intra-observer reliability were assessed using intraclass correlation (ICC). Results: The median osteotomy volume in the OWE group postoperatively was 0.87 cm3 (range=0.42–2.72). At 3 months, all but one of the OWE volumes had diminished to half or less of their initial volume. In the BGS group, the median postoperative volume was 1.30 cm3 (range=0.73–1.81) and at 12 months, 76% of the initial volume remained. Reliability between CBCT and MDCT volumetry expressed as ICC was ≥0.96. ICC for the two segmentation techniques was ≥0.99 and ICC for inter-observer reliability ≥0.97. Conclusion: CBCT volumetry is a reliable tool and comparable to MDCT to quantify bone healing of an osteotomy. [ABSTRACT FROM AUTHOR]

Although language depends on storage and composition, just what is stored or (de)composed remains unclear. We leveraged working memory load limitations to test for composition, hypothesizing that decomposed forms should particularly tax working memory. We focused on a well-studied paradigm, English inflectional morphology. We predicted that (compositional) regulars should be harder to maintain in working memory than (non-compositional) irregulars, using a 3-back production task. Frequency, phonology, orthography, and other potentially confounding factors were controlled for. Compared to irregulars, regulars and their accompanying − s / −ing -affixed filler items yielded more errors. Underscoring the decomposition of only regulars, regulars yielded more bare-stem (e.g., walk) and stem affixation errors (walks / walking) than irregulars, whereas irregulars yielded more past-tense-form affixation errors (broughts / tolded). In line with previous evidence that regulars can be stored under certain conditions, the regular-irregular difference held specifically for phonologically consistent (not inconsistent) regulars, in particular for both low and high frequency consistent regulars in males, but only for low frequency consistent regulars in females. Sensitivity analyses suggested the findings were robust. The study further elucidates the computation of inflected forms, and introduces a simple diagnostic for linguistic composition. • Our method leverages working memory limitations to test for composition in language. • Decomposed forms should tax working memory more than non-decomposed forms. • A 3-back production task revealed more errors for regular than irregular past tenses. • Further analyses revealed that the pattern was reliable and robust. • This simple diagnostic may be broadly useful to test for composition. [ABSTRACT FROM AUTHOR]

A large body of evidence suggests that people spontaneously and implicitly learn about regularities present in the visual input. Although theorized as critical for reading, this ability has been demonstrated mostly with pseudo-fonts or highly atypical artificial words. We tested whether local statistical regularities are extracted from materials that more closely resemble one's native language. In two experiments, Italian speakers saw a set of letter strings modelled on the Italian lexicon and guessed which of these strings were words in a fictitious language and which were foils. Unknown to participants, words could be distinguished from foils based on their average bigram frequency. Surprisingly, in both experiments, we found no evidence that participants relied on this regularity. Instead, lexical decisions were guided by minimal bigram frequency, a cue rooted in participants' native language. We discuss the implications of these findings for accounts of statistical learning and visual word processing. [ABSTRACT FROM AUTHOR]

Many investigations of detonation-based combustors have identified reactant mixture inhomogeneity as having a leading-order impact on wave dynamics and combustion efficiency. To examine this phenomenon in a simplified context, an array of two- and three-dimensional channel detonation simulations are conducted in the present work. The reactant mixture consists of stratified fuel and air, wherein the randomly distributed equivalence ratio field features a characteristic stratification length scale. Detailed chemical kinetics are implemented in an adaptive mesh refinement solution framework where the region near the shock front is resolved with O (100) cells per representative ZND induction length. The results show that in comparison to baseline cases with uniform reactant mixtures, reactant stratification has a marked impact on the detonation structure. Increasing the stratification length scale increases the size and irregularity of the detonation cells, yielding larger variations in wave speed. Triple point collisions in fuel-rich regions lead to local wave speeds above the notional mean CJ speed, but wave passage through inert regions causes the local wave speed and strength to diminish. Conditional statistics show that increasing the stratification length scale increases the variance in pressure and temperature in the primary reaction zone, as well as the variance in heat release over a range of mixture conditions. In addition to the reactant mixture, the impact of the boundary condition behind the detonation is also investigated. The results show that an inflow boundary condition acts to over-drive the wave, leading to higher peak pressures, smaller detonation cells, and increased reactant consumption. On the other hand, cases with a wall behind the wave exhibit weaker waves with lower peak pressures and heat release rates, as well as greater variance in conditional quantities. Comparisons between complementary two- and three-dimensional simulations show reasonable qualitative agreement in wave structure, speed, and conditional statistics. Novelty and significance statement: The present work considers two- and three-dimensional simulations of detonations propagating through stratified reactant mixtures using detailed chemical kinetics with O (100) cells per representative ZND induction length. To the authors' knowledge, it is the first study to analyze this type of configuration at this resolution and detail, as well as the first to compare two- and three-dimensional simulations of this configuration. The results have implications for the detonation wave behavior observed in practical propulsion and power-generating applications, such as rotating detonation engines. [ABSTRACT FROM AUTHOR]

Purpose: This study examined procedural and declarative learning and consolidation abilities in adults with developmental language disorder (DLD) relative to their typical language (TD) peers. Method: A total of 100 young adults (age 18-24 years) with (n = 21) and without (n = 79) DLD participated across two sites. Performance measures on a recognition memory task and a serial reaction time task were used to assess declarative and procedural memory, respectively. Performance was measured shortly after learning (8 a.m.) and again after a 12-hr, overnight delay (8 a.m.). Results: Linear mixed-effects modeling was used to examine the effects of time and group membership on task performance. For the serial reaction time task, there were significant effects of group (TD > DLD) and time (Day 1 > Day 2), but no interaction between them. For the recognition memory task, there was a significant interaction between group and time, driven by overnight gains in the TD group, combined with stable performance across days by those with DLD. Conclusions: In procedural memory, adults with DLD demonstrate a learning deficit relative to adults without DLD, but appear to have comparable retention of learned information. In declarative memory, adults with DLD demonstrate a deficit in the overnight enhancement of memory retrieval, despite typical-like learning exhibited when tested shortly after encoding. [ABSTRACT FROM AUTHOR]

Second language (L2) grammar learning is difficult. Two frameworks—the psycholinguistic lexical bottleneck hypothesis and the neurocognitive declarative/procedural model—predict that faster L2 lexical processing should facilitate L2 incidental grammar learning. We tested these predictions in a pretest–posttest syntactic adaptation study of English relative‐clause attachment preferences. First‐language German speakers listened to relative clauses disambiguated to the English low‐attachment preference (secretaries of the professor who is/naps at home)—via either a copula (e.g., is), which should be processed rapidly (copula group; n = 48), or a lexical verb (e.g., naps), which should be processed more slowly (lexical group; n = 48). Only the copula group showed significant pretest‐to‐posttest learning. Moreover, the amount of learning was predicted by procedural learning abilities in the copula group, but by vocabulary size in the lexical group. The results, which are consistent with both frameworks, show that the L2 lexicon impacts L2 grammar learning, and reveal moderating psycholinguistic and neurocognitive variables. [ABSTRACT FROM AUTHOR]