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Objectives: To compare the effectiveness of visual examination, radiographic examination and fluorescence-aided caries excavation (FACE) in detecting occlusal caries in first permanent molars in 150 children aged 6–14 years with intact occlusal surface with caries lesions without cavitation, or with darkened or deep fissures that had no clear diagnosis. Study design: Two dentists independently performed a visual oral examination, FACE and bitewing radiography. The inter-rater reliability of each detection method was determined and their specificity and sensitivity. Results: All caries detection methods showed high inter-rater reliability with absolute agreement between raters above 90%. Most caries lesions were detected by visual (75.8%) and FACE (79.1%), while only 28.8% of lesions were detected by radiography. Detection by visual examination was strongly correlated with detection by FACE (X2=37.9, Phi=0.498, p

A new experimental setup to continuously and automatically measure ultrasonic elastic wave velocities, X-ray radiography, and X-ray diffraction in large volume press is developed to explore structu...

In situ synchrotron x-ray radiography studies on the solidification sequences of non-refined and refined Al-20Zn alloys were carried out. The dendrite growth, porosity evolution, grain densities and growth rates were measured. Without and with 0.05% grain refiner, the solidification sequences appear as columnar dendrite. The average columnar dendrite growth rate of non-refined Al-20Zn alloy is larger than refined by 0.05% grain refiner. The burst growth is happened in columnar dendrite which is the first report and the time interval was about 1.2s. The columnar interdendritic region is prone to form porosities with solidification progress. The equivalent diameter of porosity with time is well fitted by Gaussian function, and the growth velocities of porosities of all sequences are faster in the first seven seconds and fluctuated with time. When the addition level of grain refiner is larger than 0.1%, the solidification sequences appear as equiaxed dendrite. The accumulation of grains of refined Al-20Zn alloys is well fitted by logistic function. The porosities disappeared during solidification with equiaxed grains. The equiaxed dendritic growth velocity, which is ~16μm/s at a cooling rate of 8K/min, is much lower than columnar.

This article presents the results of a study conducted on The Feast of Dionysius I, a previously unknown painting attributed to Henryk Siemiradzki (1843–1902), one of the most prominent Polish pain...

In general, a flux is used to braze a copper alloy. In many cases, when the molten brazing filler metal spreads in the set joint gap, vaporised flux and its residue are produced, and defects (mainly voids) are formed. Voids, which are formed on the brazed layer, cause deterioration in the strength and other properties. However, with conventional evaluation methods (e.g. ultrasonic or X-ray radiography tests), the behaviour of the molten brazing filler metal during the brazing process cannot be visually observed from the outside of the joint. Therefore, the void formation process cannot be clarified. To improve the quality of the brazed layer, it is necessary to elucidate the mechanism of void formation. The purpose of this study is to observe the behaviour of the molten brazing filler metal by performing an X-ray radiography test at the same time as brazing and to study how to reduce voids. In this study, a brass specimen was brazed with a Cu–P-based brazing filler metal. The specimen was brazed by heating in an electric furnace, and the specimen was irradiated with X-rays. The state where the molten brazing filler metal spread into the gap was photographed as the transmission image. Thereafter, the behaviour of the molten brazing filler metal was analysed.

Early detection and treatment are critical for preventing catheter allotopia in the totally implantable access ports and whenever possible, the right internal jugular vein should be selected as the first puncture point.

The purpose of this study was to verify the applicability of the compressive radiographic technique (pressures of 5, 10, 15 and 20mmHg) in the diagnosis of tracheal collapse in small breed dogs, in lateral cervicothoracic radiography. Out of the 50 dogs evaluated, 25 presented tracheal collapse (TG group), 23 did not present tracheal collapse (CG) and two were excluded because they did not tolerate a pressure of 20 mmHg. The TG group presented a smaller internal diameter of the trachea in the region of the fourth cervical vertebra (D4) and at the entrance of the thorax (TDE) compared to the CG group, in all the radiographic projections performed, as well as within the TG group where the compressive technique differed from conventional. Furthermore, there was a correlation between the clinical sign of coughing during cervical collar use and the presence of radiographic tracheal collapse at a pressure of 20 mmHg. It was concluded that the compressive radiographic technique was feasible and efficient in confirming the diagnosis of tracheal collapse in dogs, especially in the pressure of 20 mmHg, where it was associated with clinical signs, and can be used in isolation or complementary to the conventional technique. RESUMO O objetivo deste trabalho foi verificar a aplicabilidade da técnica radiográfica compressiva no diagnóstico do colapso de traqueia em cães de raças pequenas, por meio da comparação do diâmetro da traqueia durante a radiografia cervicotorácica lateral convencional e sobre influência da compressão externa com pressões de 5, 10, 15 e 20mmHg (técnica compressiva). Dos 50 cães avaliados, 25 apresentaram colapso de traqueia (grupo TG), 23 não apresentaram o colabamento traqueal (grupo controle - CG) e dois foram excluídos por não tolerarem a pressão de 20mmHg. Os diâmetros internos da traqueia na região da quarta vértebra cervical (D4) e na entrada do tórax (DET) foram menores no grupo TG em relação ao CG, em todas as projeções radiográficas realizadas, bem como dentro do grupo TG, no qual a técnica compressiva diferiu da convencional. Houve correlação entre o sinal clínico de tosse durante o uso de coleira cervical e a presença do colapso de traqueia radiográfico, na pressão de 20mmHg. Concluiu-se que a técnica radiográfica compressiva foi exequível e eficiente na confirmação do diagnóstico do colapso de traqueia em cães, especialmente na pressão de 20mmHg, em que houve associação com sinais clínicos, podendo ser utilizada de forma isolada ou complementar à técnica convencional.

The local dynamics of dendritic side arms during the growth stage were studied by in-situ radiography observations at high spatial resolution of better than 1 μm. A flat sample of a Ga–In alloy was solidified top-down applying a vertical temperature gradient. The evolving dendritic microstructure was visualized using synchrotron X-ray imaging at the beamline ID19 (ESRF, France). The experimental investigations on the dendrite evolution revealed a transition from a four-fold symmetry to a hyperbranched dendritic morphology. Both the side arm-splitting phenomenon – responsible for this morphological transition – as well as the arm growth dynamics were characterized using image processing.

A controversial set of elite jewels assumed to be of early medieval period, recovered in 1937–1938 from a burial site in Matzhausen (northeastern Bavaria) was investigated to determine their techno...

Background: There is uncertainty about the optimal guidelines for screening clinically important cervical spine injuries following blunt trauma. The Canadian C Spine rule (CCR) and the National Emergency X Radiography Utilization system (NEXUS) are two widely accepted guidelines to help emergency physicians and trauma surgeons in case of cervical blunt trauma. Methods: We conducted a prospective analytical study between June 2019 to July 2020 at Mahatma Gandhi Mission’s Hospital (MGM), Navi Mumbai comparing the diagnostic accuracy of CCR and NEXUS as applied to alert patients with trauma who were in stable condition.Result: Among the 400 trauma patients randomly selected for the study 280(70%) patients were male and 120(30%) were female. According to the NEXUS guidelines, 202(50.5%) patients and according to the CCR guidelines 210(52.5%) patients required radiography, however as per the results obtained from the cervical spine imaging only 20 (5%) patients had cervical spine injury. Both the NEXUS and CCR guidelines had similar true positive and false negative rates of 5% and 0.5% respectively. Both tests had sensitivity of about 91% and specificity 56.54% and 45.54% respectively.Conclusion: Based on studies with modest methodologic quality and only one direct comparison indicated that both CCR and NEXUS carry the same sensitivity for evaluating which patients need to undergo cervical spine imaging. Further the NEXUS guidelines have the same effectiveness as CCR for determining which patients must be subjected to cervical spine imaging.

Objective To investigate the impact of the use of different imaging units and projections on radiation dose and image quality during chest digital radiography (DR) in 3- and 4-year-old children. Methods Two hundred forty 3- and 4-year-old participants requiring chest DR were included; they were divided into three groups: supine anterior-posterior projection (APP), standing APP and standing posterior-anterior projection (PAP). Each group included 40 participants who were evaluated using the same imaging unit. The dose area product (DAP) and the entrance surface dose (ESD) were recorded after each exposure. The visual grading analysis score (VGAS) was used to evaluate image quality, and the longitudinal distance (LD) from the apex of the right lung to the apex of the right diaphragm was used to evaluate the inspiration extent. Results DAP and ESD were significantly lower in the standing PAP and APP groups than in the supine APP group (PPPPPP>0.05). Conclusion The radiation dose to superficial organs may be lower with standing PAP than with standing APP during chest DR. Standing PAP should be selected for chest DR in 3- and 4-year-old children, as it may decrease the required radiation dose.

The health systems of many countries are desperate in the face of Covid-19, which has become a pandemic worldwide and caused the death of hundreds of thousands of people. In order to keep Covid-19, which has a very high propagation rate, under control, it is necessary to develop faster, low-cost and highly accurate methods, rather than a costly Polymerase Chain Reaction test that can yield results in a few hours. In this study, a deep learning-based approach that can detect Covid-19 quickly and with high accuracy on X-ray images, which are common in every hospital and can be obtained at low cost, was proposed. Deep features were extracted from X-Ray images in RGB, CIE Lab and RGB CIE color spaces using DenseNet121 and EfficientNet B0 pre-trained deep learning architectures and then obtained features were fed into a two-stage classifier approach. Each of the classifiers in the proposed approach performed binary classification. In the first stage, healthy and infected samples were separated, and in the second stage, infected samples were detected as Covid-19 or pneumonia. In the experiments, Bi-LSTM network and well-known ensemble approaches such as Gradient Boosting, Random Forest and Extreme Gradient Boosting were used as the classifier model and it was seen that the Bi-LSTM network had a superior performance than other classifiers with 92.489% accuracy.

It is predicted that there are 600,000 to 1,000,000 patients with rheumatoid arthritis (RA) in Japan. To quantitatively diagnose RA using X-ray images, the modified total sharp score (mTSS) has been used, although, the evaluation method depends on the experience of the physicians. It desires computer-aided diagnosis (CAD) systems to improve the quality of diagnosis for RA patients. In this study, we compare a method using ridge regression (RR) and methods using 3 models (VGG16, DenseNet201 and Xception) of convolutional neural network (CNN) on mTSS prediction methods for hand rheumatoid arthritis of the hand. To compare the 4 method, we conducted an experiment on 90 RA patients using X-ray images of their hands. The experimental results showed that the mTSS prediction of erosion was best with RR, and the mTSS prediction of JSN was best with VGG16.

International audience; The present paper describes laboratory tests on steady granular flows down a smooth chute using X-ray radiography. By using an original granular chute set-up with a gate at its end, standing discontinuites in height, velocity and density, namely jumps, were produced during the granular flows. The X-ray radiography was successful to get consistent measurements of the free-surface and density profiles of the flows along the chute under different flow states: the (nearly) uniform flows before the jumps, the gradually-varied flows after the jumps, and the highly non-uniform flows across the jumps. This demonstrates the efficiency of the X-ray radiography to measure granular flows.

In this study, micro-alloyed steels were welded by using submerged arc welding method. Different welding current values ​​in experimental studies were carried out according to Table 3. After welding process, the radiographic tests were examined by using X-Ray. The experimental results indicated that microalloyed steel could be joined by using the submerged arc welding technique with sufficient strength. The results of the radiographic tests indicated that with increasing welding current, the amount of deep penetration increased in all samples.

The effect of sintering variables on the zinc loss during sintering of brass was investigated. Zinc loss, evident through mass change, starts during heating of the powder at approximately 700°C. By...

Recently, a new painting attributed to Artemisia Gentileschi was found in Ferrara, representing Judith exposing the head of Holofernes. Some analyses have been required to verify the history of this canvas, because another known painting is very similar to this one with the exception of the heads of Judith and Holofernes. This last has been attributed to the father of Artemisia, Orazio Gentileschi. Many diagnostics were performed, starting from imaging techniques: from raking light, to UV fluorescence and X-ray radiography. All of them highlighted peculiarities concerning above all the head of the main female protagonist. The results suggest that the face of Judith was subjected to various reworks in the same artistic period because of the original materials still present. This is the reason for the peculiar fragility and, due to this, the restoration of the 20th Century focused on Judith&rsquo, s face. However, in this contribution, we want to highlight the results obtained with XRF spot analysis. Indeed, the artistic palette and the restoration materials have been characterized. For example, reds are in cinnabar, while Judith&rsquo, s lips have been restored with cadmium red. The more interesting results regard the use of umber earths. In the painting, this iron-based pigment, rich in manganese, was revealed several times, and the correlation between Fe and Mn was easily verified. More than one correlation has been found due to the use of this pigment to darken the hues.

This manuscript is concerned with the development of digital inspection of casting defects using x-ray radiography images. An efficient approach for detection and classification time of casting defects in x-ray radiography images is proposed. The accuracy of this approach depends on suggested algorithms for background correction, image de-noising, image enhancement and image segmentation of casting defects. Three different algorithms are introduced for automatic detection of casting defects in x-ray images. These algorithms depend on features extraction power density spectrum (PDS) and high order statistics (HOS). An artificial neural network is utilized as a classifier for matching purposes of extracted features. The results show that HOS achieved the best recognition rate of 100% for casting defects in X-ray radiography images in comparison with other algorithms. Besides, a reduction of classification time for casting defects is another target in this paper. It is achieved using costly powerful digital processing hardware and advanced software. Furthermore, an algorithm is realized to reduce classification time of casting defects. This algorithm depends on textural features that extracted from x-ray images of casting defects. Hence, a feature reduction program code is implemented for reduction of extracted features. This program code is relied on average value of each extracted feature for normal and defect image. The numbers of extracted features are reduced from 22 to 2 features. Therefore, better execution time can be achieved for classification purposes of casting defects. The proposed algorithms are evaluated using Intel core TM i5-3470 CPU with 3.20 GHz and Intel core TM i7-3612QM CPU with 4.00 GHz. Consequently, these algorithms can be transferred into more powerful digital processing hardware such as FPGA and GPU for faster classification of casting defects. The obtained results confirm that proposed algorithms can be applied for a broad range of non-destructive applications using image processing techniques.

Unicuspid aortic valve (UAV) is an extremely rare form of congenital cardiac malformation, leading to aortic stenosis (AS), aortic regurgitation (AR), or both. We report the case of a 55-year-old man with unicommissural UAV associated with severe AS and mild AR using different multimodality imaging approaches. The excised UAV isolated after aortic valve replacement exhibited an eccentric "teardrop" opening with a slit-shaped unicommissural structure. Raman spectroscopic results indicated that 3 unevenly distributed components were deposited on the surface of the UAV, in which calcium hydroxyapatite and type-B carbonate apatite were the predominate components deposited on the surface, leading to severe AS formation.

The applicability of high-aspect anti-scattering grids for correcting the radiation pattern of pulsed X-ray tubes in the photon energy range of 20–200 keV is considered. Techniques for fabricating and testing metal anti-scattering rasters are described. Experimental studies of changes in X-ray radiation patterns using anti-scatter rasters are cited.

Many industrial processes use bins for storage of granular particles. However, the discharge of granular particles through bins is not well described quantitatively. Monitoring and analysis of the flow of particles inside bins is a challenge faced in many industrial operations. Understanding particle flow during discharge can lead to significant improvements in the design and construction of bins. The paper presents a technique to detect the particle flow pattern inside a silo using X-ray radiography. The particle flow patterns for a mass-flow bin and a funnel-flow bin were detected by the in-situ tracking of tagged granular particles during discharge. X-ray radiographs of the silo were obtained at different times of discharge, which were then analyzed using image processing techniques, and the tagged particles in the silo were tracked. The individual particle trajectories obtained explain the particle flow pattern in the silo.

The Rayleigh–Taylor (RT) instability of liquid iron alloys is important for understanding the core formation mechanism in the Earth. Here we first report the measurement of RT instability g...

We report on the design and first results from experiments looking at the formation of radiative shocks on the Shenguang-II (SG-II) laser at the Shanghai Institute of Optics and Fine Mechanics in China. Laser-heating of a two-layer CH/CH-Br foil drives a $\sim$40 km/s shock inside a gas-cell filled with argon at an initial pressure of 1 bar. The use of gas-cell targets with large (several mm) lateral and axial extent allows the shock to propagate freely without any wall interactions, and permits a large field of view to image single and colliding counter-propagating shocks with time resolved, point-projection X-ray backlighting ($\sim20$ $\mu$m source size, 4.3 keV photon energy). Single shocks were imaged up to 100 ns after the onset of the laser drive allowing to probe the growth of spatial non-uniformities in the shock apex. These results are compared with experiments looking at counter-propagating shocks, showing a symmetric drive which leads to a collision and stagnation from $\sim$40 ns onward. We present a preliminary comparison with numerical simulations with the radiation hydrodynamics code ARWEN, which provides expected plasma parameters for the design of future experiments in this facility., Comment: 16 pages, 5 figures, accepted for publication in High Power Laser Science and Engineering (25 March 2021)

We study the packing fraction of clusters in free-falling streams of spherical and irregularly shaped particles using flash X-ray radiography. The estimated packing fraction of clusters is low enough to correspond to coordination numbers less than 6. Such coordination numbers in numerical simulations correspond to aggregates that collide and grow without bouncing. Moreover, the streams of irregular particles evolved faster and formed clusters of larger sizes with lower packing fraction. This result on granular streams suggests that particle shape has a significant effect on the agglomeration process of granular materials., Accepted for publication in Physical Review E

While the basic processes of water infiltration into soil are well understood, their details are difficult to quantify due to the opaque nature of soil. In this study, we investigated the potential and limitations of X-ray radiography to measure the water front progression in a narrow sample (15 × 15 × 1 cm) filled with dry soil under simulated rainfall of high intensity (53 mm/h). The temporal resolution of the acquired infiltration movies was 133 milliseconds. We evaluated three different kinds of soil samples. i) Bare samples filled with a 1:1 mixture of a sandy loam and peat. ii) The same soil-peat mixture, but cropped with Trifolium incarnatum, Trifolium repens, Lathyrus odoratus and Lupinus regalis, all of them plants that have been reported to induce water repellency; prior to the experiments, the plants were harvested and only the roots remained in place. iii) Sandy loam soil that had been incubated for four weeks in an outside garden plot. Due to time limitations of the project, the incubation period was in early spring, which meant that plant growth in the samples was negligible. All three sample types were replicated five times, resulting in 15 individual samples. We carried out the infiltration experiments in four-fold replications, from which it follows that we collected 60 individual infiltration movies. After each infiltration round, the samples were placed in a drying room to reset them to a similar initial moisture content. The experiments aimed at testing i) whether the infiltration patterns of the four consecutive infiltration runs conducted on each sample remained identical and ii) to document differences in infiltration patterns between bare, cropped and incubated samples. We found that increasing X-ray scattering with increasing soil water contents made it challenging to evaluate the image data quantitatively. Advantages of our setup are that X-ray captures the complete water content at a specific depth and that sample boxes with irregularly shaped walls can be used to prevent preferential flow along the walls. Preliminary analyses of the data showed that the infiltration fronts in the bare and the incubated samples were less uniform than the ones for the cropped samples. In contrast, the likelihood of observing the same infiltration pattern in all four consecutive infiltration runs was larger for the bare and the incubated samples. The latter fact may have been caused by the interaction with root exudates in the cropped samples that may have been redistributed or mineralized during the wetting-drying cycles. We conclude that the here presented setup has large potential to investigate unstable infiltration phenomena into soil after an image correction approach has been developed that removes X-ray scattering artifacts. Alternatively, scattering may be suppressed by using a collimator during image acquisition.

Le texte résume les travaux de restauration d’une sculpture romaine en bronze représentant Hercule, effectués au Centre de Recherche et de Restauration des Musées de France, ainsi que le travail d’étude mené en amont et en parallèle, tant sur le plan des examens que des analyses. Il s’attache particulièrement à présenter les acquis des différentes techniques utilisées et leur importance pour la détermination des choix de traitements à mettre en œuvre. En effet, cette œuvre récemment découverte n’avait fait l’objet d’aucune restauration. Il a donc été possible de mener une étude complète, et d’orienter les traitements en fonction des résultats. The article summarises the restoration operations conducted at the C2RMF on a Roman bronze sculpture of Hercules, and the different investigations conducted before and during the restoration work, including observations and analyses. It emphasizes in particular the achievements of the various investigative techniques and their importance for determining the choice of technique to employ. The sculpture was recently discovered and had never been submitted to any restoration. It has been thus possible to execute a complete study and to direct the treatments geared towards the results.

From infancy, humans have the ability to distinguish animate agents from inert objects, and preschoolers map biological and mechanical insides to their appropriate kinds. However, less is known about how identifying something as an animate agent shapes specific inferences about its internal properties. Here, we test whether preschool children (N = 92; North American population) have specifically biological expectations about animate agents, or if they have more general expectations that animate agents should have an internal source of motion. We presented preschoolers with videos of two puppets: a “self-propelled” fur-covered puppet, and a fur-covered puppet that is seen to be moved by a human actor. In addition, we presented preschoolers with images of a familiar artifact (motorcycle) and familiar animal (sheep). For each item, we asked them to choose what they thought was inside each of these entities: nothing, biological insides, or mechanical insides. Preschoolers were less likely to say that a self-propelled fur-covered object was empty, compared to a fur-covered object that was moved by a human actor, which converges with past work with infants. However, preschoolers showed no specifically biological expectations about these objects, despite being able to accurately match biological insides to familiar animals and mechanical insides to familiar artifacts on the follow-up measure. These results suggest that preschoolers do not have specifically biological expectations about animate agents as a category, but rather general expectations that such agents should not be empty inside.

A scanner for digital radiography of large paintings has been designed and developed, aimed to in situ performances. We report here the application to “Paolo and Francesca” ($$260 \times 230 \,\hbox {cm}^{2}$$ 260 × 230 cm 2 ), masterpiece by the Italian divisionist painter Gaetano Previati (1909). The scanner has given the whole radiography in 1137 X-ray shots, which were corrected for X-ray inhomogeneities and finally processed, minimizing the visual impact of the frame structure. The original version of the painting has been brought to the light, and it appears to be a further step in the evolution of the theme frequently experienced by the artist.