X-ray Generator Research Articles

Vacuum-free femtosecond fiber laser microplasma X-ray source for radiography.

Radiographic imaging using X-rays is a tool for basic research and applications in industry, materials science, and medical diagnostics. In this article, we present a novel approach for the generation of X-rays using a vacuum-free microplasma by femtosecond fiber laser. By tightly focusing a laser pulse onto a micrometer-sized solid density near-surface plasma from a rotating copper target, we demonstrate the generation of Cu K-photons (8-9 keV) with high yield ∼ 1.6 × 109 phot/s/2π, and with a source size diameter of approximately 10 microns. Femtosecond fiber laser allows working with a high repetition rate (∼2 MHz) and moderate energy levels (10-40 µJ), ensuring the effective quasi-continuous generation of X-ray photons. Furthermore, we introduce a hybrid scheme that combines the tightly focusing laser-plasma X-ray generator with an online control unit for microplasma size source based on the back-reflected second harmonic generated in the laser-induced microplasma. The compactness and high performance of this vacuum-free femtosecond fiber laser microplasma X-ray source makes it a promising solution for advanced radiographic applications. Our preliminary results on the creation of a microfocus X-ray source provide insights into the feasibility and potential of this innovative approach.

Pelaksanaan Quality Control Pesawat Sinar X di Pelayanan Radiodiagnostik

Background: Quality Control can be used as a monitoring of the reliability of X-Ray Unit during the validity period of the Conformity Test Certificate. During the use of X-ray Unit, there is the potential for damage to components during the validity period of the certificate of passing the Compliance Test. If the X-Ray Unit Reliability Test is only carried out during the Compliance Test, then if there is a decrease in the quality and safety of the X-ray Unit it cannot be immediately known. This has the potential to endanger patients, radiation workers and the public. In Banyumas Regency, there are 80 Radiation Source Utilization Permits spread across 34 radiodiagnostic installation. Preliminary studies show that not all radiodiagnostic installation carry out routine X-ray machine reliability tests according to the Keputusan Menteri Kesehatan Republik Indonesia Nomor 1250/Menkes/SK/XII/2009 Tentang Pedoman Kendali Mutu (Quality Control) Peralatan Radiodiagnostik.
 Method: This research type is qualitative with survey of 20 radiodiagnostic installation using a questionnaire instrument. Quality control conducted periodically includes kVp accuracy test, linearity and reproducibility mA, exposure time accuracy test, tube leak test, collimator beam suitability test, collimator shutter efficiency test, collimator light strength test, HVL measurement, implementation of reject analysis program and availability and qualifications of quality control officers and availability of quality control equipment. Then the data will be grouped based on research objectives and presented descriptively.
 Result: From the results of data collection, 1 hospital did not have a quality control officer and 4 hospitals had a quality control officer with an educational background of Diploma IV in Radiology Engineering without any Radiology Equipment Quality Control training. Meanwhile, 15 hospitals have quality control officers with an educational background in the Medical Physics Undergraduate Program and have attended training in Quality Control of Radiology Equipment. Of the 20 hospital radiology installations, there were 7 hospitals that did not carry out the Reject Analysis Program. This was done with the assumption that Digital Radiography had been used in both the CR and DR modalities. A number of 13 hospitals continued to carry out the Reject Analysis Program even though they had used Digital Radiography. Of the 20 hospital radiology installations, there are 6 hospitals that independently carry out X-ray unit testing within the framework of a quality control program. However, only 1 hospital conducts regular testing. Testing is also limited to the accuracy of the collimator field and the strong light of the collimator. Fourteen hospitals did not carry out a quality control program independently but only carried out an X-ray unit calibration test once a year which was carried out by BPFK and an X-ray unit distributor company.
 Conclusion: The implementation of quality control of x-ray machines on a regular basis has not been carried out by all radiodiagnostic services, even though they already have quality control officers. One of the reasons is the availability of quality control equipment needed for testing and supervision of radiodiagnostic service management. The role of management of radiodiagnostic services is needed to overcome these problems.
 
 Keyword : Quality Control Programe, Compliance Test, X-Ray Unit

Performance evaluation of stationary and mobile radiography systems in Indonesia.

An analysis and evaluation has been carried out on each test parameter contained in the compliance test of 1016 stationary and 480 mobile radiography devices compiled by the Indonesian Nuclear Energy Regulatory Agency (Badan Pengawas Tenaga Nuklir, BAPETEN) from 2019 to 2020. The data were categorised and analysed based on the devices' age to observe the correlation of performance with the age of the X-ray machine. In addition, the implementation level of the Automatic Exposure Control (AEC) system test of the stationary radiography X-ray modality is also reviewed. The results of the evaluation showed that 89.9% of the stationary radiography devices unconditionally pass the test, 5.2% are in the status of 'conditional pass' and 4.9% fail the test. On the other hand, 84.8% of mobile radiography devices unconditionally pass the test, 2.1% are in the status of 'conditional pass' and 13.1% fail the test. From the evaluation conducted, there is no observable correlation between the age of the modality and the results of the compliance test. Overall, only 9.2% of stationary radiography X-ray compliance test reports have included the AEC test since it is not a mandatory requirement of the national protocol.

Measurement of Entrance Surface Air Kerma of plain abdominal radiography in some Nigerian health facilities

Background : Patient dose assessments in many Nigerian radiological departments have shown large inter- and intra-hospital variations for the same type of radiological examinations, hence, there is a need for regular monitoring of radiological equipment and measurement of patient dose in our health facilities. The main objective of this survey was to evaluate the Entrance Surface Dose Air Kerma (ESAK) of the patients who underwent abdominal (anteroposterior; AP) radiography in ten health facilities in Southern Nigeria.
 Material and Methods: A total of ten health facilities comprising private and public health facilities were included in this investigation. A total of 223 adult patients who weighed within 70±5kg `were considered in this survey. The ESAK was calculated from the tube output of the x-ray machines and the exposure parameters utilized during examinations according to the International Atomic Energy Agency code of practice.
 Results : The mean ESAK values obtained from the health centres ranged from 1.00 milligray (mGy) to 17.21mGy. The maximum/minimum ratio of individual ESAK which is the range factor (RF) varied from 1.3 to 6.1.
 Conclusion and Recommendation : Variations were observed in patient dose values among radiological units. The entrance surface air kerma (ESAK) obtained in the study were comparable with the dose values in the UK- 2010 review in most cases. The intra-radiological unit patient dose variations, as revealed by the range factor show that the operation technique employed was not fully optimized and that dose reduction is possible without degrading image quality. Therefore, there is a need for regular monitoring of radiographic equipment and periodic surveys of the patient dose.

Multicolor x-rays from free electron-driven van der Waals heterostructures.

The emergence of van der Waals (vdW) heterostructures has led to precise and versatile methods of fabricating devices with atomic-scale accuracies. Hence, vdW heterostructures have shown much promise for technologies including photodetectors, photocatalysis, photovoltaic devices, ultrafast photonic devices, and field-effect transistors. These applications, however, remain confined to optical and suboptical regimes. Here, we theoretically show and experimentally demonstrate the use of vdW heterostructures as platforms for multicolor x-ray generation. By driving the vdW heterostructures with free electrons in a table-top setup, we generate x-ray photons whose output spectral profile can be user-customized via the heterostructure design and even controlled in real time. We show that the multicolor photon energies and their corresponding intensities can be tailored by varying the electron energy, the electron beam position, as well as the geometry and composition of the vdW heterostructure. Our results reveal the promise of vdW heterostructures in realizing highly versatile x-ray sources for emerging applications in advanced x-ray imaging and spectroscopy.

Investigation of silver nanoparticles embedded in extracted gelatins from camel, bovine, and fish bones for possible use in radiation dosimetry

Abstract Gelatins from camel, bovine, and fish bones were successfully extracted by using chemical pretreatment and heating methods. The bones were demineralized for 3 days at ambient temperature using hydrochloric acid solutions (0.5–1 M), and the collagen was partially hydrolyzed by preheating in distilled water at 75–80°C for 3 h, followed by extraction temperature at 90°C for 1 h. Free-standing films of gelatin entrained with silver nanoparticles (Gel/AgNPs) at low concentrations (1.25, 2.5, and 5 mM) were synthesized as radiation dosimeters. A high-energy ultrasonic homogenizer was used to dissolve the gelatin in distilled water and to disperse the AgNPs in the gelatin. The nanocomposites’ morphology and crystallinity were investigated using scanning electron microscopy (SEM), optical absorption, and Fourier transform infrared (FTIR) spectroscopies. Dose enhancement was assessed using X-ray irradiations with beam energies below and above silver K-edge. The beam was configured by setting the X-ray generator at 15, 25.5, and 35 kV potential and a beam current of 1 mA. An X-ray detector is used to detect the number of electrons after passing through Gel/AgNPs samples. The use of AgNPs embedded in gelatin caused the enhancement of X-ray radiation absorption, and the highest percentage of linearity for the dosimeter was found to be 90% in the optical range of 395 nm to 425 nm. The preliminary results demonstrated that Gel/AgNPs material may be used in radiation dosimetry for low-energy radiotherapy sources.

Investigating focal spot position drift in a mobile imaging system equipped with a monobloc-based x-ray generator.

Misalignment or double-contouring artifacts can appear in high-resolution 3D cone beam computed tomography (CBCT) images, potentially indicating geometric accuracy issues in the projection data. Such artifacts may go unnoticed in low-resolution images and could be associated with changes in the focal spot (FS)position. High-resolution 3D-CBCT imaging by a mobile imaging device with a large gantry clearance offers more versatility for clinical workflows in image-guided brachytherapy (IGBT), intraoperative radiation therapy (IORT), and spinal, as well as maxillofacial surgery. However, misalignment or double-contouring artifacts hinder workflow advancements in these domains. This paper introduces intrinsic calibration and geometrical correction methods as extensions to a well-established technique for addressing geometrical deviations resulting from factors such as gravity or mechanical inconsistencies. These extensions cover shifts and drifts of the FS depending on FS size selection, temperature, tube current, and tube potential. The proposed methods effectively mitigate artifacts in high-resolution CBCT images stemming from geometrical inaccuracies in projection data, without requiring additional equipment like a pinholedevice. Geometrical offsets and drifts of the x-ray tube FS were characterized on a mobile multi-purpose imaging system, the ImagingRing-m. A pinhole-like experiment was simulated by adjusting the movable collimation unit to a small rectangular aperture within the FS size range. The influence of filament selection, that is, FS size, temperature, the relatively low tube currents, as well as tube potential settings have been studied on two different monobloc types sharing the same x-ray tube insert. The Catphan 504 and an Alderson head phantom were used to assess resulting imageartifacts. Switching the FS size to one different from what was used for geometrical (gravitation, mechanical variations) calibration induced the most notable position changes of the x-ray FS, resulting in double-contouring artifacts and blurring of high-resolution 3D-CBCT images. Incorporating these shifts into a geometrical correction method effectively minimized these artifacts. Thermal drifts exhibited the second largest geometrical changes, comparable to FS size shifts across the thermal operating conditions of the x-ray system. The proposed thermal drift compensation markedly reduced thermal drift effects. Tube current and potential had little impact within the range of available tube currents, eliminating the need for compensation in currentapplications. Augmenting the geometrical calibration pipeline with proposed FS drift compensations yielded significant enhancements in image quality for high-resolution reconstructions. While compensation for thermal effects posed challenges, it proved achievable. The roles of tube current and potential were found to benegligible.

Synthetic 3D Spinal Vertebrae Reconstruction from Biplanar X-rays Utilizing Generative Adversarial Networks.

Computed tomography (CT) offers detailed insights into the internal anatomy of patients, particularly for spinal vertebrae examination. However, CT scans are associated with higher radiation exposure and cost compared to conventional X-ray imaging. In this study, we applied a Generative Adversarial Network (GAN) framework to reconstruct 3D spinal vertebrae structures from synthetic biplanar X-ray images, specifically focusing on anterior and lateral views. The synthetic X-ray images were generated using the DRRGenerator module in 3D Slicer by incorporating segmentations of spinal vertebrae in CT scans for the region of interest. This approach leverages a novel feature fusion technique based on X2CT-GAN to combine information from both views and employs a combination of mean squared error (MSE) loss and adversarial loss to train the generator, resulting in high-quality synthetic 3D spinal vertebrae CTs. A total of n = 440 CT data were processed. We evaluated the performance of our model using multiple metrics, including mean absolute error (MAE) (for each slice of the 3D volume (MAE0) and for the entire 3D volume (MAE)), cosine similarity, peak signal-to-noise ratio (PSNR), 3D peak signal-to-noise ratio (PSNR-3D), and structural similarity index (SSIM). The average PSNR was 28.394 dB, PSNR-3D was 27.432, SSIM was 0.468, cosine similarity was 0.484, MAE0 was 0.034, and MAE was 85.359. The results demonstrated the effectiveness of this approach in reconstructing 3D spinal vertebrae structures from biplanar X-rays, although some limitations in accurately capturing the fine bone structures and maintaining the precise morphology of the vertebrae were present. This technique has the potential to enhance the diagnostic capabilities of low-cost X-ray machines while reducing radiation exposure and cost associated with CT scans, paving the way for future applications in spinal imaging and diagnosis.

The Implementation of MuDirac in Geant4: A Preliminary Approach to the Improvement of the Simulation of the Muonic Atom Cascade Process

Muonic Atom X-ray Emission spectroscopy (µ-XES) is a novel elemental technique that exploits the high-energy X-rays emitted from the muonic atom cascade process to characterize materials. At the ISIS Neutron and Muon Source, the technique is performed at Port4 of the RIKEN-RAL facility, with a user demand that is increasing every year. To cope with this demand, it is necessary to continue to improve the method, either for the hardware (detectors, acquisition, etc.) or software (data analysis and interpretation). In both cases, Monte Carlo codes play an important role: with a simulation, it is possible to reproduce the experimental setup and provide a reliable quantitative analysis. In this work, we investigate the capabilities of GEANT4 for such applications. From the results, we observed that the generation of X-rays, especially the kα and kβ transition for high Z atoms, are not in agreement with the experimental ones. A solution to this issue, other than an attempt with a small modification of the GEANT4 cascade class, could be provided by a database of transition energy calculated by a Dirac equation software called MuDirac. The software, developed by the UKRI scientific computing department and the ISIS muon group, can compute all the transition energy for a given nuclide. Here, preliminary results of the implementation of the MuDirac database in GEANT4 are reported.

Use of Vacuum to Increase the Effectiveness of X-Ray Tube Maintenance

Each device requires redundancy, including the X-ray machine. In an X-ray machine, there is an important component as the location for the creation of X-rays, namely the X-ray tube. This tube needs routine maintenance to increase the tube's lifetime. In addition, maintenance that was originally done manually, with this device can be done automatically and more quickly. In addition, maintenance that was originally done manually can be done automatically and faster with this device. X-ray tube oil vacuum is used as an effective solution for the maintenance of an X-ray tube machine that lasts for days. This device comes with easy use, equipped with two buttons and a display. This device can increase the productivity of both the device and the technician itself. The application of the use of X-ray tube oil vacuum is intended for hospitals and health facilities that have active X-ray machines. This device has been able to be built. Based on the results, it has a 2.5% error for the measurement at minimum and maximum pressure and a 3% error at -15 KPa pressure. The volume of the X-ray tube fully filled is always the same for each measurement. It can be concluded that this device can be effective in time because it only takes minutes to fill the X-ray tube up to full. Still, many parts can be improved and developed, such as the size and the weight.

Role of emergency teleradiology in a mass motorcycle event: the experience of the 2021 International Six Days of Enduro (ISDE).

Provision of healthcare support at mass gathering sporting events is of paramount importance for the success of the event. Many of such events, like motorsports, have been increasingly taking place in remote and austere environments. In these settings, the use of first-line diagnostic tools, such as point of care ultrasound and portable X-ray, could aid in definitive care on the field for patients with minor trauma while also ensuring fast access to the appropriate level of care for patients requiring hospitalization. As part of the ISDE 2021 medical response plan, a field hospital equipped with portable digital X-ray and telemedicine was established. Data on patient admission, triage, treatments, diagnostics, and outcomes were collected for analysis. During the 6-day competition, 79 patients sought medical care at the field hospital, with traumatic injuries accounting for 77% of cases. Of these, 47 were athletes and 32 were non-athletes. The majority (91%) arrived spontaneously, while 9% were transported directly. Upon admission, 68 patients were triaged as non-urgent (code 3) and 11 as urgent (code 2). Of those admitted, 69 received treatment and were discharged at the field hospital, while 10 were transferred elsewhere. Notably, four patients had major trauma, two had isolated fractures, and one needed a CT scan after losing consciousness. Overall, 29 missions were conducted on the race field, including 13 primary transports to local hospitals and 6 to the field hospital. Primary transport was primarily due to major trauma. Among 31 patients who had radiological exams, 11 (35.5%) had traumatic injuries. Of these, 5 were treated with braces and casts and discharged without hospitalization, 3 were advised for post-event care, and 3 were hospitalized. In contrast, patients with negative X-rays received on-site treatment, with 7 able to continue competing. In summary, the successful implementation of portable X-ray machines and teleradiology at remote and austere high-risk sporting events holds great promise for enhancing on-site medical capabilities, allowing clinicians informed decisions, avoiding unnecessary hospitalization, and allowing athletes to continue with their competition. Provided that challenges related to cost, safety, connectivity, and power supply are effectively addressed.

Pulmonary abnormality screening on chest x-rays from different machine specifications: a generalized AI-based image manipulation pipeline

BackgroundChest x-ray is commonly used for pulmonary abnormality screening. However, since the image characteristics of x-rays highly depend on the machine specifications, an artificial intelligence (AI) model developed for specific equipment usually fails when clinically applied to various machines. To overcome this problem, we propose an image manipulation pipeline.MethodsA total of 15,010 chest x-rays from systems with different generators/detectors were retrospectively collected from five institutions from May 2020 to February 2021. We developed an AI model to classify pulmonary abnormalities using x-rays from a single system. Then, we externally tested its performance on chest x-rays from various machine specifications. We compared the area under the receiver operating characteristics curve (AUC) of AI models developed using conventional image processing pipelines (histogram equalization [HE], contrast-limited histogram equalization [CLAHE], and unsharp masking [UM] with common data augmentations) with that of the proposed manipulation pipeline (XM-pipeline).ResultsThe XM-pipeline model showed the highest performance for all the datasets of different machine specifications, such as chest x-rays acquired from a computed radiography system (n = 356, AUC 0.944 for XM-pipeline versus 0.917 for HE, 0.705 for CLAHE, 0.544 for UM, ple 0.001, for all) and from a mobile x-ray generator (n = 204, AUC 0.949 for XM-pipeline versus 0.933 for HE, p = 0.042, 0.932 for CLAHE (p = 0.009), 0.925 for UM (p = 0.001).ConclusionsApplying the XM-pipeline to AI training increased the diagnostic performance of the AI model on the chest x-rays of different machine configurations.Relevance statementThe proposed training pipeline would successfully promote a wide application of the AI model for abnormality screening when chest x-rays are acquired using various x-ray machines.Key points• AI models developed using x-rays of a specific machine suffer from generalization.• We proposed a new image processing pipeline to address the generalization problem.• AI models were tested using multicenter external x-ray datasets of various machines.• AI with our pipeline achieved the highest diagnostic performance than conventional methods.Graphical

THE INFLUENCE OF FLIGHT SAFETY FACILITIES AGAINST SECURITY IN THE CARGO TERMINAL MINANGKABAU INTERNATIONAL AIRPORT

Minangkabau International Airport is an airport located in Padang Pariaman, West Sumatra (ICAO Code : WIEE ; IATA Code : PDG), has a Domestic Terminal, VIP Terminal, International Terminal, and Cargo Terminal. At the cargo terminal, problems were found that arose due to a lack of security facilities and personnel. So we need a study that can provide an explanation regarding aviation security facilities at the Minangkabau International Airport Cargo Terminal. The purpose of this study was to determine the effect of aviation security facilities on security at the cargo terminal capable of providing security for goods and cargo. The type of this research is descriptive quantitative using data obtained from observations, distributing questionnaires, and literature studies. Respondents from the questionnaire were Aviation Security and Angkasa Pura Cargo personnel, with a total sample of 61 people. The results of the discussion, there is an influence of variable X (aviation security facilities) on Y (security at the cargo terminal) has a relationship or correlation between variables with 0.78 (high, strong correlation) and the R square value is 0.608 or 60.8 % . There are things that need to be optimized in terms of the influence of aviation security facilities on security at the Minangkabau International Airport Cargo Terminal, the need to increase the number of Aviation Security personnel licensed by Junior Avsec to operate 1 x-ray machine with a minimum of 3 people and the need for security facilities is not yet adequate, such as the absence of a Walk Through Metal Detector.

Study of the length of the anterior base of the skull in children from the Moscow region

Relevance. One of the starting points for calculating the parameters of growth and the ratio of the jaws is considered to be the sagittal size of the anterior base of the skull. To this day, many orthodontists are guided by the average values of the anterior skull base, found in 1972. This article is devoted to the study of the comparison of the average statistical sagittal dimensions of the length of the anterior skull base in children of the Moscow region aged 4 to 16 years with occlusal ratios according to the first Angle class in 2023 with the data proposed in the studies of Dr. Jarabak in 1972.Objective. To compare the average sagittal dimensions of the length of the anterior base of the skull in children of the Moscow region aged from 4 to 16 years with occlusal ratios for the first Engl class in 2023 with the data proposed in the studies of Dr. Jarabak in 1972.Materials and methods. The study included 331 people aged 4 to 16 years. The sagittal dimensions of the length of the anterior base of the skull were calculated in the digital program for the analysis of CBCT in children with occlusive ratios in the first class of male and female Engl on the digital X-ray machine Planmeca ProMax 3D Max X-ray diagnostic centers «Golden Section».Results. Male patients of the Moscow region approach the lower limits of the growth value of the anterior base of the skull only by the age of 12 and reach the confident values of the norm proposed by Dr. Jarabak only by the age of 16. And female patients in the Moscow region, for the most part, do not reach the limits of the norm proposed by Dr. Jarabak, lagging in values by 2–3 mm in a smaller direction.Conclusion. It is necessary to calculate and develop norms for Russian children, taking into account racial characteristics, environmental conditions, nutritional conditions, physical and social development, which differ significantly, but at the same time strongly affect the growth and formation of skeletal structures.

ZNAČAJ KLASIČNE RADIOGRAFIJE PLUĆA U OTKRIVANJU TUBERKULOZE PLUĆA

ABSTRACT
 
 Diagnostic radiology provides a non-invasive insight into the anatomy and physiology of the human body and is one of the most useful tools in modern medicine. Accelerated technological development has led to improved image quality and the ability to obtain additional diagnostic information necessary for accurate and rapid diagnostics. As in other fields of medicine, in diagnostic radiology, all elements of risk must be balanced against the benefits arising from the use of a given diagnostic method.
 Aim: study is to determine the age and gender structure of the subjects who came for radiographs, to prove whether the X-ray has a significant role in detecting lung tuberculosis, whether the radiological record matches the findings of a pneumophysiologist or whether a microbiological analysis is needed, and to determine whether tuberculosis detected by classical radiography is also proven.
 Prospective method included 50 adult respondents from the Public Health Center of the Canton of Sarajevo, of different age and gender structures, who performed radiographic pulmonary imaging and processing of pneumophysiological findings in the period from 01.01.2018. do 30.05.2019. years. X-rays were taken from the classic Siemens Multix X-ray machine. Patients' medical records, microbiological examination of sputum on BC, pneumophysiological findings, radiographs and radiological findings from the radiological information system and the PACS system were used for the data. We used a retrospective study that included descriptive statistics, standard deviation, arithmetic mean, and correlation coefficient.
 Results: show that there is no significant statistical difference by gender, the average age of the respondents was 50, 52 years. 
 X-ray imaging as a diagnostic procedure is of great importance in the detection of pulmonary tuberculosis, and 72% of the subjects had pulmonary tuberculosis first compared with the findings of pneumophysiologists, and bacteriological analysis was used in 28% subjects due to suspected pneumophysiologists in the diagnosis. By comparing the correlation of the pneumophysiologist and the bacteriological analysis, the X-ray showed 100% lung tuberculosis.

A Panoramic X-ray as a Supportive Diagnostic Tool for the Screening of Osteoporosis in Patients with Hemophilia A and B.

Hemophilia is associated with an increased risk of developing osteoporosis and osteopenia. The aim of the study was to interpret the usefulness of fractal analysis of the trabecular bone of the mandible (FD) and selected radiomorphic indices (the antegonial index (AI) and Klemetti index (KI)) to assess the risk of reduced bone mineral density (BMD) in patients with hemophilia A/B. The study group consisted of 50 patients with type A/B hemophilia. The control group consisted of 25 males without congenital bleeding disorders. The patients had a panoramic radiograph taken with the same X-ray machine (Vistapano S, Durr Dental, Bietigheim-Bissingen, Germany). The AudaXCeph software (Audax d.o.o., Ljubljana, Slovenia) was used to evaluate the AI index, and the ImageJ, software with a specially prepared script, was used to evaluate the FD. The mandibular cortex was assessed distal to the mental foramen using the Klemetti index. There were no statistically significant differences between the AI, KI and FD values between the study group and the control group. This study indicated the lack of usefulness of AI, KI and fractal analysis in identifying patients with hemophilia at risk of reduced bone mass.

Absolute calibration of the spectral sensitivity of an x-ray streak camera over the 0.1-10keV spectral range equipped with CsI photocathode.

In this paper, we report the absolute measurement of the spectral sensitivity of a bilamellar tube x-ray streak camera (XRSC) over the 0.1-10keV range equipped with a CsI photocathode for Laser MégaJoule (LMJ) fusion experiments. This calibration of the XRSC is performed in static mode by using two multi-anode x-ray generators. Two silicon drift detectors (SDDs) previously calibrated at the Physikalisch-Technische-Bundesanstalt radiometric laboratory are used as secondary standards. Both x-ray generators work with a specific monochromator for radiometric measurements. In the sub-keV region, a 1 m-grazing incidence Rowland geometry monochromator specifically developed to handle LMJ's x-ray camera is used, whereas for higher energies (>2keV), a double-crystal monochromator is employed. The absolute spectral sensitivity of the XRSC is obtained by comparing the CCD counts of the XRSC output with the output counts in x-ray lines recorded by the SDD. The results obtained below 1.2keV are, to our knowledge, the first measurements of the spectral sensitivity of an XRSC in the soft x-ray range with a CsI photocathode. Comparison with a model describing the spectral dependence of the sensitivity of the XRSC revealed that measurements obtained in the sub-keV region are greater than expected, whereas they agree with the model above 4.5keV. There may be several contributors to this behavior, including the grain morphology of the CsI layer and exposure to air.

Screening the phytotoxicity of micro/nanoplastics through non-targeted metallomics with synchrotron radiation X-ray fluorescence and deep learning: Taking micro/nano polyethylene terephthalate as an example

Microplastics (MPs) and nanoplastics (NPs) are global pollutants with emerging concerns. Methods to predict and screen their toxicity are crucial. Elemental dyshomeostasis can be used to assess toxicity of environmental pollutants. Non-targeted metallomics, combining synchrotron radiation X-ray fluorescence (SRXRF) and machine learning, has successfully differentiated cancer patients from healthy individuals. The whole idea of this work is to screen the phytotoxicity of nano polyethylene terephthalate (nPET) and micro polyethylene terephthalate (mPET) through non-targeted metallomics with SRXRF and deep learning algorithms. Firstly, Seed germination, seedling growth, photosynthetic changes, and antioxidant activity were used to evaluate the toxicity of mPET and nPET. It was showed that nPET, at 10 mg/L, was more toxic to rice seedlings, inhibiting growth and impairing chlorophyll content, MDA content, and SOD activity compared to mPET. Then, rice seedling leaves exposed to nPET or mPET was examined with SRXRF, and the SRXRF data was differentiated with deep learning algorithms. It was showed that the one-dimensional convolutional neural network (1D-CNN) model achieved 98.99% accuracy without data preprocessing in screening mPET and nPET exposure. In all, non-targeted metallomics with SRXRF and 1D-CNN can effectively screen the exposure and phytotoxicity of nPET/mPET and potentially other emerging pollutants. Further research is needed to assess the phytotoxicity of different types of MPs/NPs using non-targeted metallomics.

How efficient are metal-polymer and dual-metals-polymer non-lead radiation shields?

Lead shields are often used to attenuate ionising radiations. However, to make lighter, recyclable and more efficient shields compared to lead, combinations of new metallic compounds together with polymer, for example, flexible polyvinyl chloride (PVC) have been developed recently. In this study, the capabilities of non-lead radiation shields made of one or two metallic compounds and polymer were evaluated. Monte Carlo (MC)-based BEAMnrc code was used to build a functional model based on a Philips X-ray machine in the range of radiographic energies. The MC model was then verified by IPEM Report 78 as a standardised global reference. The MC model was then used to evaluate the efficiency of non-lead-based garments made of metallic compound and polymer (MCP) including BaSO4 -PVC, Bi2 O3 -PVC, Sn-PVC and W-PVC, as well as dual-metallic compounds and polymer (DMCP) including Bi2 O3 -BaSO4 -PVC, Bi2 O3 -Sn-PVC, W-Sn-PVC and W-BaSO4 -PVC. The absorbed doses were determined at the surface of a water phantom and compared directly with the doses obtained for 0.5 mm pure lead (Pb). Bi2 O3 -BaSO4 -PVC and W-BaSO4 -PVC were found to be efficient shields for most of the energies. In addition to the above radiation shields, Bi2 O3 -Sn-PVC was also found to be effective for the spectrum of 60 keV. Bi2 O3 -BaSO4 -PVC as a non-lead dual metals-PVC shield was shown to be more efficient than pure lead in diagnostic X-ray range. Combination of two metals-PVC, a low atomic number (Z) metal together with a high atomic number metal, and also single-metal-PVC shields were shown to be efficient enough to apply as radiation protection shields instead of lead-based garments.

Comparative Evaluation of the Relationship Between Airway Inadequacy, Head Posture, and Craniofacial Morphology in Mouth-Breathing and Nasal-Breathing Patients: A Cephalometric Observational Study.

The process of respiration is the primary factor of the posture of the jaws and tongue. Thus, a changed respiratory form like mouth breathing can change the posture of the head, jaw, and tongue. This, in turn, could change the equilibrium of pressure on the jaws and teeth thus affecting jaw growth and teeth positions. The influence of nasorespiratory function on craniofacial growth has stimulated interest and debate for more than a century. Mouth breathing is the reason for numerous orthodontic glitches such as a mouth breather's face evolving aberrantly because of of functional disruptions triggered by chronic airway obstruction. The relationship between nasorespiratory function and dentofacial development remains controversial despite the long-standing clinical concern of orthodontists, so there was a need to evaluate and compare the relationship between head posture, airway inadequacy, and craniofacial morphology in mouth breathers and nasal breathers. Forty patients were selected and divided equally into two groups: mouth breathers and nasal breathers. Patients were diagnosed as mouth breathers based on physical examination and a history of chronic allergic rhinitis, adenoid, and tonsil enlargement. Lateral cephalograms were taken for all patients in the natural head position (NHP) with the Planmeca Proline XC Dimax3 x-ray machine (Planmeca, Helsinki-Uusimaa, Finland). All lateral cephalograms were traced and analysis was done to check airway, head posture, and craniofacial morphology. Descriptive statistics were performed to obtain the means and standard deviation of all the sample sizes. Unpaired t test was performed between nasal breathers and mouth breathers to check and evaluate the relationship. Mouth-breathing patients varied from nasal-breathing patients in airway adequacy and craniofacial morphology. A little, but not statistically significant, difference was seen in head posture between the two groups. Early interception of mouth breathing in patients could be very helpful, as the postural changes in the mouth-breathing patients, if continued for a longer period of time, could be the reason for severe skeletal deformities as well as dental malocclusion.