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This study aims to investigate the effect of the laser beam overlap rate on the mechanical properties of Al3003 aluminum alloy arc weldment with laser peening. To determine the optimal laser beam overlap rate for laser peening of the weldment, peening experiments were conducted on bead-welded and butt-welded specimens with varying overlap rates, and the effect of the beam overlap rate was analyzed. As the overlap rate increased, the residual stress changed from tensile to compressive, with the highest level of compressive residual stress at the overlap rate of 75%. Laser peening was performed on the aluminum weldment of the prototype, applying the optimal peening conditions identified earlier. As a result of comparing the residual stress, hardness, and tensile strength of the weld before and after laser peening, it was found that the tensile residual stress in the weldment was improved to a compressive residual stress of about −50 MPa or more. The hardness and tensile strength of the weld increased after peening, and the mechanical properties were also improved. [ABSTRACT FROM AUTHOR]

Although many studies reported the safety and efficacy of high-intensity focused ultrasound (HIFU) therapy, there are still worries about internal organ injury. However, reports of abdominal wall hernias after HIFU therapy are rare. We present three cases of abdominal wall hernias without skin injury after HIFU therapy in uterine adenomyosis or fibroids. The diagnosis was often delayed because of vague symptoms, inadequate clinical suspicion, and delayed proper image studies. Abdominal wall hernia should be recognized as a possible complication after HIFU and be suspected when the patient presents with unordinary abdominal swelling and/or pain that lasts for more than a few months after the procedure. [ABSTRACT FROM AUTHOR]

Building upon past studies of curriculum textbooks in the US, this paper presents an analytical framework that classifies curriculum texts according to their representation of reconceptualized curriculum scholarship. It uses four indicators of the representation of curriculum scholarship in the analyses of eight curriculum texts published in the USA in the 1990s: the authors stated intentions; the organization of the table of contents; the treatment of the forms of reconceptualism; and the ratio of curriculum and non-curriculum journal citations. The analysis finds that reconceptualized curriculum scholarship has been at least mentioned, if not extensively treated, in most texts since the mid-1980s, and that this approach is most comprehensively treated in books published in the 1990s. [This paper re-presents a paper by Pyeong-gook Kim and J. Dan Marshall which appeared in JCS, 37(3), pp. 291-311. As a result of errors in the production process, the tables were omitted from the previous publication of the paper. The editors and the publisher apologize to Pyeong-gook Kim and J. Dan Marshall, and the readers of JCS, for this unfortunate mistake.]

Background and Aims The diagnostic performance of diffusion-weighted imaging magnetic resonance enterography [DWI-MRE] has not been clearly established in a paediatric population. We systematically evaluated the diagnostic performance of DWI-MRE for the detection of bowel inflammation in paediatric patients with suspected or known inflammatory bowel disease [IBD]. Methods MEDLINE/PubMed, EMBASE, Web of science and the Cochrane library were searched for articles investigating the diagnostic performance of DWI-MRE for the detection of bowel inflammation in paediatric patients with suspected or known IBD up to December 31, 2020. Pooled sensitivity and specificity were calculated using a bivariate random-effects model. Pooled inter-reader agreement for the interpretation of DWI-MRE was also calculated. This study was registered as PROSPERO CRD42021228754. Results Nine studies covering 400 paediatric patients were included. The pooled sensitivity and specificity of DWI-MRE for the detection of bowel inflammation were 0.93 (95% confidence interval [CI], 0.88–0.96) and 0.96 [95% CI, 0.87–0.99], respectively. Substantial heterogeneity was noted in both sensitivity [ I 2 = 66%; p  < 0.01] and specificity [ I 2 = 94%; p  < 0.01]. Meta-regression analysis identified that the use of spasmolytics contributed to higher specificity [0.89–0.99] and that quantitative assessment with an apparent diffusion coefficient cut-off value contributed to lower sensitivity [0.93–0.85] and specificity [0.98–0.72]. The pooled coefficient of inter-reader agreement, including four studies using visual assessment, was 0.97 [95% CI, 0.78–1.00]. Conclusions DWI-MRE, especially when used with spasmolytics, is accurate for the detection of bowel inflammation in paediatric patients with suspected or known IBD. Quantitative measurement of ADC is not practical for this purpose. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the technical performance of acoustic radiation force impulse (ARFI) imaging (two‐dimensional shear wave elastography [2D‐SWE] and point shear wave elastography [p‐SWE]) for measuring renal parenchymal stiffness. Methods: EMBASE and PubMed databases were searched for studies reporting technical performance of ARFI imaging in terms of technical failure, interobserver agreement, and/or intraobserver agreement. The proportion of technical failure and intraclass correlation coefficients (ICCs) for interobserver and intraobserver agreement was pooled. The pooled estimates of native and transplanted kidneys were obtained separately. Meta‐regression and subgroup analyses were conducted to explore heterogeneity. Results: Twenty‐four studies (2993 patients) were included. The pooled proportions of technical failure were 4.3% (95% confidence interval [CI] 2.2–8.5%) and 6.6% (95% CI 4.0–10.7%) in native and transplanted kidneys, respectively. The pooled ICCs of interobserver agreement were 0.70 (95% CI 0.68–0.83) and 0.81 (95% CI 0.68–0.89), indicating moderate and good agreement in native and transplanted kidneys, respectively. The pooled ICC showed good (0.77; 95% CI 0.49–0.91) intraobserver agreement in native kidneys. Regarding interobserver agreement in transplanted kidneys, ROI location (mid pole only versus others) was a significant factor of heterogeneity (P =.04). Conclusions: The ARFI‐based SWE techniques show good technical performance for measuring renal parenchymal stiffness. The wide range of SWE protocols necessitates development of standardized guidelines on the use of renal ARFI imaging. Access the CME test here and search by article title. [ABSTRACT FROM AUTHOR]

Background and Aims Evidence is limited regarding clinical course and magnetic resonance imaging [MRI] features of perianal fistula [PAF] in Korean children with Crohn's disease [CD]. We investigated MRI features of PAF and associations with long-term outcomes. Methods We retrospectively analysed 243 patients with pelvic MRI for diagnosis of CD. Incidence of clinically evident PAF at diagnosis was determined, as were the proportions of patients with clinical failure [failure to achieve fistula healing within 1 year] and recurrence [new/recurrent PAF after fistula healing within 1 year]. Associations between outcomes and MRI features, specified in modified Van Assche index and MAGNIFI-CD, were evaluated. Associations between later development of clinically evident PAF and subclinical PAF detected on MRI at diagnosis were evaluated. Results Among 243 included patients, 108 [44.4%] and 76 [31.3%] had clinically evident and subclinical PAF at diagnosis, respectively; 66.4% of the patients with clinically evident PAF achieved fistula healing within 1 year, and 32.7% of those patients developed recurrence. Fistula length and dominant features of the tracts were associated with clinical failure, and fistula length was associated with recurrence. Clinically evident PAF developed in 17.0% of the patients without clinically evident PAF at diagnosis. We did not find statistically significant association between subclinical PAF and later development of clinically evident PAF [adjusted hazard ratio, 2.438; p = 0.15]. Conclusions A considerable proportion of Korean paediatric CD patients had clinically evident and subclinical PAF. Fistula length and dominant feature of the tract on MRI are useful predictors of outcomes. [ABSTRACT FROM AUTHOR]

Stent migration is a significant obstacle to successful stent placement. There has been no investigation of the effect and quantitative interpretation of flaps attached to a plastic stent (PS) on antimigration. The antimigration effects of the number of flaps on a PS in a 3D-printed pancreatic phantom (3DP) and extracted porcine pancreas (EPP) were investigated. Four PS types were used in this study: stent without flaps (type 1), stent with two flaps (type 2), stent with four horizontally made flaps (type 3), and stent with four vertically made flaps (type 4). The stents were measured and compared for antimigration force (AMF) in the 3DP and EPP using a customized measuring method and an integrated measuring device. The mean maximum AMFs (MAMFs) in types 2, 3, and 4 were significantly higher than that in type 1 (all p < 0.001). Moreover, the mean MAMFs in types 3 and 4 were significantly higher than that in type 2 (all p < 0.001). When the flaps were removed from the pancreatic duct, the AMF decreased rapidly. As the number of flaps increased, the antimigration effects significantly increased in the 3DP and EPP. However, the direction of the flaps did not affect the MAMF. The position of the flaps attached to the surface of the stent affected the AMF. [ABSTRACT FROM AUTHOR]

Background: The development of deep learning (DL) algorithms is a three-step process—training, tuning, and testing. Studies are inconsistent in the use of the term "validation", with some using it to refer to tuning and others testing, which hinders accurate delivery of information and may inadvertently exaggerate the performance of DL algorithms. We investigated the extent of inconsistency in usage of the term "validation" in studies on the accuracy of DL algorithms in providing diagnosis from medical imaging. Methods and findings: We analyzed the full texts of research papers cited in two recent systematic reviews. The papers were categorized according to whether the term "validation" was used to refer to tuning alone, both tuning and testing, or testing alone. We analyzed whether paper characteristics (i.e., journal category, field of study, year of print publication, journal impact factor [JIF], and nature of test data) were associated with the usage of the terminology using multivariable logistic regression analysis with generalized estimating equations. Of 201 papers published in 125 journals, 118 (58.7%), 9 (4.5%), and 74 (36.8%) used the term to refer to tuning alone, both tuning and testing, and testing alone, respectively. A weak association was noted between higher JIF and using the term to refer to testing (i.e., testing alone or both tuning and testing) instead of tuning alone (vs. JIF <5; JIF 5 to 10: adjusted odds ratio 2.11, P = 0.042; JIF >10: adjusted odds ratio 2.41, P = 0.089). Journal category, field of study, year of print publication, and nature of test data were not significantly associated with the terminology usage. Conclusions: Existing literature has a significant degree of inconsistency in using the term "validation" when referring to the steps in DL algorithm development. Efforts are needed to improve the accuracy and clarity in the terminology usage. [ABSTRACT FROM AUTHOR]