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1.
Mater Struct ; 57(4): 56, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601013

RESUMO

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.

2.
Emerg Med J ; 36(2): 77-88, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30696778

RESUMO

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.


Assuntos
Articulação do Ombro/anormalidades , Dor de Ombro/diagnóstico , Criança , Futebol Americano/lesões , Humanos , Masculino , Amplitude de Movimento Articular , Lesões do Ombro , Articulação do Ombro/fisiopatologia , Dor de Ombro/diagnóstico por imagem
3.
Emerg Med J ; 36(10): 613-616, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31530583

RESUMO

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.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Fraturas do Rádio/diagnóstico por imagem , Fraturas da Ulna/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Países Baixos , Estudos Prospectivos , Radiografia/efeitos adversos , Ultrassonografia
4.
Emerg Med J ; 34(10): 676-679, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28963377

RESUMO

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.


Assuntos
Síndrome de DiGeorge/diagnóstico , Faringe/anormalidades , Adulto , Transtornos de Deglutição/etiologia , Síndrome de DiGeorge/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Faringite/etiologia , Faringe/lesões , Violência
7.
Emerg Med J ; 32(5): 348-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25142034

RESUMO

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.


Assuntos
Pescoço/diagnóstico por imagem , Supraglotite/diagnóstico , Adulto , Serviço Hospitalar de Emergência , Feminino , Humanos , Laringoscopia , Funções Verossimilhança , Masculino , Estudos Prospectivos , Radiografia , Sensibilidade e Especificidade
9.
Emerg Med J ; 31(5): 380-3, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23397014

RESUMO

OBJECTIVE: To derive a maximally sensitive decision rule for clinical practice to rule out the need for x-ray examination after elbow injury in adults and children. METHODS: Emergency department patients with acute elbow injury were recruited. Practitioners used their usual judgement to assess whether x-ray examination was required. Radiographs were reported on by radiologists blind to clinical assessment. Patients not x-rayed were followed-up at 7 days by telephone interview, and those with ongoing pain were recalled for assessment. Recursive partitioning was used to derive a maximally sensitive decision tool. Inter-rater variability for significant discriminators was subsequently evaluated by a cohort of 20 emergency department clinicians. RESULTS: 492 patients were recruited (May 2006-November 2008): 50.4% were male; 26.8% were children; 444 (90.2%) had an x-ray; 167 (37.6%) showed abnormality. A follow-up telephone interview was conducted with 28; none were recalled. Thirteen could not be contacted, none of whom returned within 3 months. Sixteen patients with fractures were able to fully extend their elbow. The sensitivity of elbow extension alone was 84% (95% CI 77% to 88%), with specificity of 54% (95% CI 53% to 58%). A 100% sensitive (95% CI 97% to 100%) decision rule for adults (n=348) was derived based on (1) inability to fully extend the elbow, (2) tenderness over radial head, olecranon or medial epicondyle, and (3) presence of bruising (specificity 24% (95% CI 19% to 30%)). A similar rule for children could not be derived. CONCLUSIONS: A simple and highly sensitive clinical decision rule for adult elbow fracture was derived in our cohort. A validation study in a second population is now required. At present, we are unable to recommend a rule-out strategy for elbow injuries in children.


Assuntos
Técnicas de Apoio para a Decisão , Árvores de Decisões , Lesões no Cotovelo , Fraturas do Rádio/diagnóstico por imagem , Fraturas da Ulna/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Radiografia , Amplitude de Movimento Articular , Sensibilidade e Especificidade , Adulto Jovem
10.
Emerg Med J ; 31(7): 591-592, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23704755

RESUMO

OBJECTIVE: To investigate whether elderly patients, presenting following trauma and requiring immobilisation and imaging of the cervical spine, require increased use of CT and spend longer immobilised when compared to the younger population. METHODS: A retrospective chart review was undertaken of 35 adults aged 18-65 years, and 32 adults over 65 years, requiring cervical spine imaging following trauma. RESULTS: 1 of the 35 younger patients, and 16 of the 32 elderly patients, underwent CT. Elderly patients spent 1:05 h longer immobilised (p<0.005). CONCLUSIONS: Half of the elderly patients underwent CT, and they were immobilised for significantly longer than younger patients. Measures should be adopted to facilitate early diagnosis and mitigate complications of prolonged immobilisation in elderly patients with neck trauma.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/lesões , Imobilização/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Pol J Radiol ; 78(3): 48-56, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24115960

RESUMO

The first-line imaging technique for diagnosis inflammation in musculo-skeletal organs in rheumatoid arthritis (RA) is planar X-ray examination, which was for many years the first and the only single tool for RA diagnostics and response evaluation. Today, in the era of more aggressive RA treatment, ultrasound examination (US) and magnetic resonance imaging (MRI) are also frequently used. US is used to detect early signs of inflammation within the soft tissue. MRI allows to assess the soft tissue and bone marrow involvement in case of inflammation and/or infection. MRI is capable of detecting more inflammatory lesions and erosions than US, X-ray, or CT. Standard scintigraphy plays a crucial role, and data from positron emission tomography (PET) are also promising. These functional imaging techniques are used in detection of inflammation and/or infection in case of ambiguous results being obtained by other techniques or at other clinics. In patients with RA, scintigraphy plays a key role in the differential diagnosis of hip, knee, etc. endoprosthesis disorders, including mechanical or septic loosening.

12.
Multimed Tools Appl ; : 1-54, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37362676

RESUMO

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.

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