Chloride-induced corrosion of steel in concrete-insights from bimodal neutron and X-ray microtomography combined with ex-situ microscopy.

The steel-concrete interface (SCI) is known to play a major role in corrosion of steel in concrete, but a fundamental understanding is still lacking. One reason is that concrete's opacity complicates the study of internal processes. Here, we report on the application of bimodal X-ray and neutron microtomography as in-situ imaging techniques to elucidate the mechanism of steel corrosion in concrete. The study demonstrates that the segmentation of the specimen components of relevance-steel, cementitious matrix, aggregates, voids, corrosion products-obtained through bimodal X-ray and neutron imaging is more reliable than that based on the results of each of the two techniques separately. Further, we suggest the combination of tomographic in-situ imaging with ex-situ SEM analysis of targeted sections, selected based on the segmented tomograms. These in-situ and ex-situ characterization techniques were applied to study localized corrosion in a very early stage under laboratory chloride-exposure conditions, using reinforced concrete cores retrieved from a concrete bridge. Several interesting observations were made. First, the acquired images revealed the formation of several corrosion sites close to each other. Second, the morphology of the corrosion pits was relatively shallow. Finally, only about half of the total 31 corrosion initiation spots were in close proximity to interfacial macroscopic air voids, and > 90% of the more than 160 interfacial macroscopic air voids were free from corrosion. The findings have implications for the mechanistic understanding of corrosion of steel in concrete and suggest that multimodal in-situ imaging is a valuable technique for further related studies. Supplementary Information: The online version contains supplementary material available at 10.1617/s11527-024-02337-7.

Bio-medical imaging (X-ray, CT, ultrasound, ECG), genome sequences applications of deep neural network and machine learning in diagnosis, detection, classification, and segmentation of COVID-19: a Meta-analysis & systematic review.

This review investigates how Deep Machine Learning (DML) has dealt with the Covid-19 epidemic and provides recommendations for future Covid-19 research. Despite the fact that vaccines for this epidemic have been developed, DL methods have proven to be a valuable asset in radiologists' arsenals for the automated assessment of Covid-19. This detailed review debates the techniques and applications developed for Covid-19 findings using DL systems. It also provides insights into notable datasets used to train neural networks, data partitioning, and various performance measurement metrics. The PRISMA taxonomy has been formed based on pretrained(45 systems) and hybrid/custom(17 systems) models with radiography modalities. A total of 62 systems with respect to X-ray(32), CT(19), ultrasound(7), ECG(2), and genome sequence(2) based modalities as taxonomy are selected from the studied articles. We originate by valuing the present phase of DL and conclude with significant limitations. The restrictions contain incomprehensibility, simplification measures, learning from incomplete labeled data, and data secrecy. Moreover, DML can be utilized to detect and classify Covid-19 from other COPD illnesses. The proposed literature review has found many DL-based systems to fight against Covid19. We expect this article will assist in speeding up the procedure of DL for Covid-19 researchers, including medical, radiology technicians, and data engineers.

Point-of-care ultrasound compared with conventional radiographic evaluation in children with suspected distal forearm fractures in the Netherlands: a diagnostic accuracy study.

BACKGROUND: Distal forearm fractures are common in children. The reference standard to diagnose these fractures is by conventional radiography, which exposes these patients to harmful radiation. Ultrasound (US) seems to be a good alternative. However, emergency physicians (EPs) in the Netherlands have limited experience in using US for diagnosing fractures in children. OBJECTIVE: The primary objective was to determine the accuracy of US, performed by a Dutch EP, compared with conventional radiography, in diagnosing distal forearm fractures in children. As a secondary objective, differences in pain scores during the performance of both US and plain radiography were determined. METHODS: Children, aged between 0 and 14 years old, suspected of having a distal forearm fracture were enrolled at the Emergency Department. US and radiographic findings were compared. Statistics for accuracy were calculated. Pain scores were recorded during US and radiography and compared as well. All participating operators received an hour-long pretrial training. RESULTS: 100 patients were enrolled. The mean age was 9.5 years (SD, 3.6), and 50% were women. Overall diagnostic accuracy was 92% (95% CI 85%-96%). The sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios for US were 95% (95% CI 87% to 99%), 86% (95% CI 71% to 95%), 92% (95% CI 83% to 97%), 91% (95% CI 76% to 98%), 6.86 (95% CI 3.04 to 15.51) and 0.05 (95% CI 0.02 to 0.17), respectively. The pain scores during US and radiographic imaging were 3.3 and 4.6, respectively (p<0.01). CONCLUSIONS: In this study, we showed that US is an accurate method for diagnosing distal forearm fractures in children. The main advantages are that it is radiation-free and rapidly practicable, and that patients experience it as less painful than radiography. Moreover, this study has proven that with minimal experience in US, good diagnostic accuracy can be achieved after brief training.

Paediatric shoulder injury: don't get sucked in!

CLINICAL INTRODUCTION: A healthy 8-year-old boy presented to the ED with acute left shoulder pain. He had been playing football and his left arm was pulled by an opposition team member. He fell to the ground and landed on his left shoulder causing pain. On examination after analgesia, active and passive movement of the shoulder joint was possible in all directions but range of motion was limited by pain. There was no visible swelling or bruising throughout the shoulder girdle. A radiograph of the shoulder was obtained (figure 1).emermed;36/2/77/F1F1F1Figure 1Plain radiograph of the left shoulder. QUESTION: What radiographic finding is seen for this patient?Glenohumeral lipohaemarthrosis.Acromioclavicular joint disruption.Intra-articular gas.Intra-articular loose body.

A frog in the throat?

CLINICAL INTRODUCTION: A 44-year-old woman, with an unremarkable medical history, presented in the middle of the night with discomfort in her throat. She described being assaulted by an assailant who put his 'fist in her mouth', trying to suffocate her. On examination, she had normal observations and no signs of injury, other than scratch marks around her mouth; she reported no odynophagia and was able to swallow fluids readily. During examination, she complained that lying flat made her increasingly uncomfortable and was causing burgeoning dyspnoea. She had lateral soft tissue radiography of her neck as shown in figure 1.emermed;34/10/676/EMERMED2016205919F1F1EMERMED2016205919F1Figure 1Lateral neck soft tissue radiograph of the 44-year-old woman. QUESTION: What is the diagnosis? Caustic stricture of the oesophagusPharyngeal perforationPharyngeal pouchBoerhaave's syndrome.

Characterization of an indirect X-ray imaging detector by simulation and experiment.

We describe a comprehensive model of a commercial indirect X-ray imaging detector that accurately predicts the detector point spread function and its dependence on X-ray energy. The model was validated by measurements using monochromatic synchrotron radiation and extended to polychromatic X-ray sources. Our approach can be used to predict the performance of an imaging detector and can be used to optimize imaging experiments with broad-band X-ray sources.

Diagnostic accuracy of lateral neck radiography in ruling out supraglottitis: a prospective observational study.

OBJECTIVE: To assess the diagnostic accuracy of lateral neck radiographs (LNR) for acute supraglottitis in adults. DESIGN: A single centre prospective observational study. SETTING: Emergency department at Kurashiki Central Hospital, Japan. PARTICIPANTS: Adult patients who underwent LNR to detect supraglottitis. MAIN OUTCOME MEASURES: Presence of supraglottitis, based on nasopharyngeal laryngoscopy or a follow-up telephone call, 7-30 days after the visit. RESULTS: 140 patients had LNR during the study period. 35 patients were excluded from further analysis because of lack of consent. Of the 105 eligible patients, 21 patients (20%) were given the diagnosis of supraglottitis: 17 of 29 with a radiographic abnormality, and 4 of 76 patients without a radiographic abnormality. Three of the four cases where LNR was negative was grade 1, and all cases of grade 3 or higher had abnormal LNR. Sensitivity and specificity (95% CI) of LNR for supraglottitis were 81.0% (64.2 to 97.7) and 85.7% (78.2 to 93.2), respectively. The positive predictive value of LNR was 58.6% (40.7 to 76.5) and the negative predictive value was 94.7% (89.7 to 99.8). The positive likelihood ratio of LNR was 5.67 (3.27 to 9.82) and the negative likelihood ratio was 0.22 (0.10 to 0.51). CONCLUSIONS: LNR showed only moderate sensitivity and specificity for supraglottitis and would miss some cases of supraglottitis if the pre-test probability is high. LNR was very sensitive for grade 3 or higher supraglottitis, but would miss milder cases. TRIAL REGISTRATION: UMIN000011928.