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Gradual switching between multiple resistance levels is desirable for analog in-memory computing using resistive random-access memory (RRAM). However, the filamentary switching of HfOx-based conventional RRAM often yields only two stable memory states instead of gradual switching between multiple resistance states. Here, we demonstrate that a thermal barrier of Ge2Sb2Te5 (GST) between HfOx and the bottom electrode (TiN) enables wider and weaker filaments, by promoting heat spreading laterally inside the HfOx. Scanning thermal microscopy suggests that HfOx + GST devices have a wider heating region than control devices with only HfOx, indicating the formation of a wider filament. Such wider filaments can have multiple stable conduction paths, resulting in a memory device with more gradual and linear switching. The thermally enhanced HfOx + GST devices also have higher on/off ratio (>103) than control devices (<102) and a median set voltage lower by approximately 1 V (∼35%), with a corresponding reduction of the switching power. Our HfOx + GST RRAM shows 2× gradual switching range using fast (∼ns) identical pulse trains with amplitude less than 2 V. [ABSTRACT FROM AUTHOR]

Background: Arthroscopic rotator cuff surgery is an effective treatment for rotator cuff tears with the considered use of double-row repair techniques becoming popular in the last decade. We aim to compare the effects of double- and single-row arthroscopic rotator cuff repairs (ARCR) on repair integrity (RI) and acromiohumeral distance (AHD)., Methods: In this observational study, we retrospectively identified 98 patients with degenerative rotator cuff tear treated with arthroscopic rotator cuff repair between 2016 and 2019. We excluded 22 patients with partial-thickness tears, 15 with associated subscapularis or SLAP tears, 13 with massive tears, and 5 patients lost to follow-up; we included 43 patients who had ARCR for full-thickness cuff tear and clinical, radiologic follow-up. Of these 43 patients, 23 are grouped as double-row repair group (DRG) and 20 as single-row repair group (SRG). A minimum of 12 months after the surgery, bilateral shoulder MRIs were obtained. Contralateral shoulders without asymptomatic rotator cuff tears served as a control group (CG). The operating surgeon and two other surgeons experienced in arthroscopy blindly measured the AHD and determined the RI at the control MRIs in all groups. Functional assessments relied on UCLA and qDASH Scores., Results: The mean age was 57.89 (45-78) years, and the mean follow-up time was 28,65 (21-43) months. The mean AHD of the CG was 9.7 ± 0.96 mm, the preoperative AHD of DRG was 8.62 ± 1.45 mm, and SRG was 9.71 ± 0.95 mm. The postoperative mean AHD of DRG 9.61 ± 1.83 mm and SRG was 10.21 ± 1.97 mm. AHD differences between the preoperative and postoperative groups were significant (P=0.009). The increase of the AHD in the double-row group was significantly higher than the single-row group (P=0.004). There was a high correlation between the RI and DASH scores (P=0.005). RI did not correlate with the repair method (P=0.580)., Conclusion: Although double-row repairs can maintain greater AHD than single-row repairs in the clinical setting, this difference did not affect functional results. Regardless of the surgical intervention, functional results are favourable if RI is achieved., Level of Evidence: Level III, Retrospective Cohort Study.

Objective: This study aimed to compare the clinical and radiological findings of radical reduction (open reduction and Salter innominate osteotomy combined with femoral osteotomy) for children of walking age, younger and older than 4 years in the treatment of with developmental dysplasia of the hip (DDH)., Methods: In this retrospective study, children of walking age with DDH who underwent radical reduction between 2008 and 2014 were identified. They were then divided into 2 groups according to the age at which the surgery was performed: before and after the age of 4 years. Improvement in the acetabular index was examined on follow-up radiographs. The presence of avascular necrosis (AVN) was determined and classified on the basis of the Kalamchi-MacEwen classification on final follow-up radiographs. Clinical assessment was performed with the modified McKay criteria at the final follow-up appointment., Results: A total of 19 children (14 girls, 5 boys; mean age=37.5±21 months) (25 hips) were included. Their mean age was 27.9±4.9 and 63.3±19.7 months in children operated before and after the age of 4 years, respectively. The mean follow-up time was 29.9±19 and 19.6±5 months in children operated before and after the age of 4 years, respectively. No significant difference was observed in improvements in the acetabular index between children younger than 4 years (24±6.9°) and those older than 4 years (20.7±6.7°) (p=0.25). According to the modified McKay criteria, all the children younger than 4 years exhibited excellent or good clinical results compared with those operated after the age of 4 years (67%) (p=0.013). At the final follow-up, 64% of all patients demonstrated no radiographical sign of AVN. The rates of AVN were significantly higher in children operated after the age of 4 years (33%) than in those operated before the age of 4 years (19%) (p=0.049)., Conclusion: Better clinical and radiographical results can be expected from radical reduction in children undergoing surgery before the age of 4 years., Level of Evidence: level III, Therapeutic Study.

Introduction Distal radius fractures are the most frequent fractures seen in pediatric population and usually treated with closed reduction and casting. However, there is a risk of reduction loss and/or angulations in distal radial metaphyseal fractures. The purpose of this study is to evaluate the radiological and functional results of pediatric patients with distal radius metaphyseal fractures in which excessive displacement and/or angulations were accepted and to question upper acceptable limits in light of current literature. Methods Patients between five and 15 years of age with displaced distal radius fractures who were treated conservatively with significant angulation or translation were included in this study. Patients' demographic data were gathered from hospital's digital database. Clinical and radiological evaluations of all patients were done prospectively based on the last outpatient clinic control. Range of motion of wrist and elbow joint was measured with a goniometry, neurovascular status was documented, muscle strength was assessed and finally existing deformity measurements were performed clinically. Radiological evaluation was performed on pre-reduction, post-reduction, cast removal, 6th and 12th months and final examination radiographs. All measured values were compared with uninjured side. Radiologically, the percentage of translation, the amount of angulations, the distance from the fracture to the epiphyseal line, and the radius lengths were measured. Radial inclination and palmar tilt angles as well as ulnar variance and residual angulation were measured in both antero-posterior (AP) and lateral forearm radiographs. The Mann-Whitney U test was used to compare the variables in SPSS version 21. p < 0.05 was considered statistically significant. Results Twenty-nine patients with a mean age of 8.8 ± 3.1 years were included in this study. The mean follow-up duration was 17.4 ± 6.7 months. Compared to the uninjured side, in 24 (83%) patients, there were no limitations on wrist movements except five patients in forearm pronation clinically. In patients with re-displacement, the mean displacement occurrence time was 13.3 ± 4.9 (7-21) days. The translational and/or angulations in AP and lateral radiographs fully remodeled at the end of 6th month. Conclusion This study demonstrates that radial and dorsal angular deformities up to 39° and 22° volar angulation and complete displacement correct fully in children up to 10 years old. In children between 10 and 15 years, the dorsal angulation up to 38°, radial angulation up to 23°, and volar angulation up to 16° are acceptable for remodeling capacity of the child., Competing Interests: The authors have declared that no competing interests exist.