Atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such events.These pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric transmission.To quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction.The proposed method is an improvement over the traditional analytical method that only computes direct-transmission X-rays.The traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo method.Our improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain scenarios.Moreover,its computation time is 48,000 times faster than that of the Monte Carlo method.These results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

Pulmonary Edema and Pleural Effusion Detection Using Efficient Net-V1-B4 Architecture and AdamW Optimizer from Chest X-Rays Images

This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was formed by combining 28,309 samples from the ChestX-ray14,PadChest,and CheXpert databases,with 10,287,6022,and 12,000 samples representing Pleural Effusion,Pulmonary Edema,and Normal cases,respectively.Consequently,the preprocessing step involves applying the Contrast Limited Adaptive Histogram Equalization(CLAHE)method to boost the local contrast of the X-ray samples,then resizing the images to 380×380 dimensions,followed by using the data augmentation technique.The classification task employs a deep learning model based on the EfficientNet-V1-B4 architecture and is trained using the AdamW optimizer.The proposed multiclass system achieved an accuracy(ACC)of 98.3%,recall of 98.3%,precision of 98.7%,and F1-score of 98.7%.Moreover,the robustness of the model was revealed by the Receiver Operating Characteristic(ROC)analysis,which demonstrated an Area Under the Curve(AUC)of 1.00 for edema and normal cases and 0.99 for effusion.The experimental results demonstrate the superiority of the proposedmulti-class system,which has the potential to assist clinicians in timely and accurate diagnosis,leading to improved patient outcomes.Notably,ablation-CAM visualization at the last convolutional layer portrayed further enhanced diagnostic capabilities with heat maps on X-ray images,which will aid clinicians in interpreting and localizing abnormalities more effectively.

Single Tooth Segmentation on Panoramic X-Rays Using End-to-End Deep Neural Networks

In dentistry, panoramic X-ray images are extensively used by dentists for tooth structure analysis and disease diagnosis. However, the manual analysis of these images is time-consuming and prone to misdiagnosis or overlooked. While deep learning techniques have been employed to segment teeth in panoramic X-ray images, accurate segmentation of individual teeth remains an underexplored area. In this study, we propose an end-to-end deep learning method that effectively addresses this challenge by employing an improved combinatorial loss function to separate the boundaries of adjacent teeth, enabling precise segmentation of individual teeth in panoramic X-ray images. We validate the feasibility of our approach using a challenging dataset. By training our segmentation network on 115 panoramic X-ray images, we achieve an intersection over union (IoU) of 86.56% for tooth segmentation and an accuracy of 65.52% in tooth counting on 87 test set images. Experimental results demonstrate the significant improvement of our proposed method in single tooth segmentation compared to existing methods.

Role of contrast-enhanced serial/spot abdominal X-rays in perioperative follow-up of patients undergoing abdominal surgery:An observational clinical study

BACKGROUND Many imaging methods such as ultrasonography,computed tomography(CT),magnetic resonance imaging,and endoscopy are used to identify the problems or complications that occur in the perioperative period and to determine the appropriate therapeutic approach.Specialists at surgical clinics and intensive care units sometimes need diagnostic procedures that can give quick results or reveal unexpected results.In particular,rapid on-site evaluation of patients followed under intensive care conditions has several advantages.AIM To determine the problems developing in patients in the perioperative period by contrast-enhanced abdominal X-ray(CE-AXR),revealing their current status or defining the effectiveness of CE-AXR.METHODS The files of the patients who underwent hepatopancreatobiliary or upper gastrointestinal surgery,whose CE-AXR film was taken,were reviewed retrospectively.Abdominal X-ray radiographs taken after ingestion of a watersoluble contrast agent(iohexol,300 mg,50 cc vial)and its application in a drain,nasogastric tube,or stent were evaluated.The contribution of the data obtained in patients who underwent CE-AXR to the diagnosis,follow-up,and treatment processes and the effectiveness of the application were investigated.RESULTS CE-AXR was applied to 131 patients in our clinic,most of whom underwent hepatopancreatobiliary or upper gastrointestinal surgery.It was determined that the data obtained from CE-AXR films taken in 98(74.8%)of the patients contributed to the diagnosis,treatment,and follow-up expectations and positively affected the clinical processes.CONCLUSION CE-AXR is a simple procedure that can be applied anywhere,especially in intensive care patients and at bedside,with a portable X-ray device.The simplicity of the procedure,less radiation exposure for the patients,less time wastage,reduction in the CT and endoscopy procedure burden and costs,quick results,rapid assessment of the situation,and enabling the monitoring of processes with repetitive procedures are important advantages.X-rays taken will be useful in terms of being a reference value during the follow-up period of the patient and determining the situation in medicolegal processes.

Histogram Matched Chest X-Rays Based Tuberculosis Detection Using CNN

Tuberculosis(TB)is a severe infection that mostly affects the lungs and kills millions of people’s lives every year.Tuberculosis can be diagnosed using chest X-rays(CXR)and data-driven deep learning(DL)approaches.Because of its better automated feature extraction capability,convolutional neural net-works(CNNs)trained on natural images are particularly effective in image cate-gorization.A combination of 3001 normal and 3001 TB CXR images was gathered for this study from different accessible public datasets.Ten different deep CNNs(Resnet50,Resnet101,Resnet152,InceptionV3,VGG16,VGG19,DenseNet121,DenseNet169,DenseNet201,MobileNet)are trained and tested for identifying TB and normal cases.This study presents a deep CNN approach based on histogram matched CXR images that does not require object segmenta-tion of interest,and this coupled methodology of histogram matching with the CXRs improves the accuracy and detection performance of CNN models for TB detection.Furthermore,this research contains two separate experiments that used CXR images with and without histogram matching to classify TB and non-TB CXRs using deep CNNs.It was able to accurately detect TB from CXR images using pre-processing,data augmentation,and deep CNN models.Without histogram matching the best accuracy,sensitivity,specificity,precision and F1-score in the detection of TB using CXR images among ten models are 99.25%,99.48%,99.52%,99.48%and 99.22%respectively.With histogram matching the best accuracy,sensitivity,specificity,precision and F1-score are 99.58%,99.82%,99.67%,99.65%and 99.56%respectively.The proposed meth-odology,which has cutting-edge performance,will be useful in computer-assisted TB diagnosis and aids in minimizing irregularities in TB detection in developing countries.

肺癌骨转移^(99m)Tc-MDP骨显像的临床价值及与CT、X-rays检查对比观察

目的 评价99mTc MDP骨显像诊断肺癌骨转移的临床价值。方法 12 8例肺癌骨转移患者常规行99mTc MDP骨显像检查。 91例患者同时行骨显像、CT检查 :74例病变部位相符者同时行骨显像、X rays检查。分别对比观察99mTc MDP骨显像与CT、X rays诊断肺癌骨转移的阳性检出率 ,并分析相互之间产生差异的原因和机制。结果 全部病例中 ,99mTc MDP骨显像阳性检出率为 91.4% (117/12 8) ,假阳性率为 12 .0 % (16/13 3 ) ,假阴性率 8.5 9% (11/12 8) ;对比观察99mTc MDP骨显像与CT ,阳性检出率分别为 85 .7% (78/91)、2 9.7% (2 2 /74) ,(P <0 .0 1,已剔除部位不相符因素 ,但未剔除X线检查部位包括不全因素 )。结论 99mTc MDP骨显像诊断肺癌骨转移具有较高的临床价值 ,辅以CT、X rays检查可提高阳性诊断的准确性。

The development,performances and applications of the monochromatic X-rays facilities in(0.218–301)keV at NIM,China

Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the universe.Countries worldwide have launched numerous space exploration satellites.Accurate calibration of the detectors on the ground is a crucial element for space science satellites to obtain observational results.For the purpose of providing calibration for various satellite-borne detectors,multiple monochromatic X-rays facilities have been built at the National Institute of Metrology,P.R.China(NIM).These facilities mainly pertain to grating diffraction and Bragg diffraction,and the energy range of the produced monochromatic X-rays is 0.218–301 ke V.These facilities have a high performance in terms of energy stability,monochromaticity,and flux stability.The monochromaticity was greater than 3.0%.The energy stability of the facility is 0.02%at 25 ke V over 8 h,and the flux stability was within 1.0%at 25 ke V over 8 h.Calibration experiments on the properties of satellite-borne detectors,such as energy linearity,energy resolution,detection efficiency,and temperature response,can be conducted at the facilities.Thus far,the calibration of two satellites has been completed by the authors,and the work on three other satellites is in progress.This study will contribute to the advancement of X-ray astronomy the development of Chinese space science.

Attenuation coefficients of gamma and X-rays passing through six materials

The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chosen to measure gamma and X-ray attenuation coefficients and to explore the mechanisms of interaction of gamma and X-rays with matter of various kinds.It is shown that the attenuation coefficients first decrease and then increase with increase in the radiation(photon)energy.The attenuation of gamma and X-rays passing through materials with high atomic number is greater than that in materials with low atomic number.The attenuation minimum is related to the atomic number of the irradiated materials.The larger the atomic number is,the lower the energy corresponding to attenuation minimum is.Photoelectric and Compton effects are the main processes when gamma rays pass through individual materials with high and low atomic numbers,respectively.Therefore,for radiotherapy and radiation protection,different methods should be considered and selected for the use of gamma and X-rays of different energies for use in different materials.

Understanding fundamentals of electrochemical reactions with tender X-rays:A new lab-based operando X-ray photoelectron spectroscopy method for probing liquid/solid and gas/solid interfaces across a variety of electrochemical systems

Electrocatalysis is key to improving energy efficiency,reducing carbon emissions,and providing a sustainable way of meeting global energy needs.Therefore,elucidating electrochemical reaction mechanisms at the electrolyte/electrode interfaces is essential for developing advanced renewable energy technologies.However,the direct probing of real-time interfacial changes,i.e.,the surface intermediates,chemical environment,and electronic structure,under operating conditions is challenging and necessitates the use of in situ methods.Herein,we present a new lab-based instrument commissioned to perform in situ chemical analysis at liquid/solid interfaces using ambient pressure X-ray photoelectron spectroscopy(APXPS).This setup takes advantage of a chromium source of tender X-rays and is designed to study liquid/solid interfaces by the“dip and pull”method.Each of the main components was carefully described,and the results of performance tests are presented.Using a three-electrode setup,the system can probe the intermediate species and potential shifts across the liquid electrolyte/solid electrode interface.In addition,we demonstrate how this system allows the study of interfacial changes at gas/solid interfaces using a case study:a sodium–oxygen model battery.However,the use of APXPS in electrochemical studies is still in the early stages,so we summarize the current challenges and some developmental frontiers.Despite the challenges,we expect that joint efforts to improve instruments and the electrochemical setup will enable us to obtain a better understanding of the composition–reactivity relationship at electrochemical interfaces under realistic reaction conditions.

Energy spectrum of multi-radiation of X-rays in a low energy Mather-type plasma focus device

The multi-radiation of X-rays was investigated with special attention to their energy spectrum in a Mather-type plasma focus device （operated with argon gas）. The analysis is based on the effect of anomalous resistances. To study the energy spectrum, a four-channel diode X-ray spectrometer was used along with a special set of filters. The filters were suitable for detection of medium range X-rays as well as hard X-rays with energy exceeding 30 keV. The results indicate that the anomalous resistivity effect during the post pinch phase may cause multi-radiation of X-rays with a total duration of 300 ± 50 ns. The significant contribution of Cu-Kα was due to the medium range X-rays, nonetheless, hard X-rays with energies greater than 15 keV also participate in the process. The total emitted X-ray energy in the forms of Cu-K and Cu-K/3 was around 0.14 ± 0.02 （J/Sr） and 0.04 ±0.01 （J/Sr）, respectively. The total energy of the emitted hard X-ray （〉 15 keV） was around 0.12± 0.02 （J/Sr）.

Effect of X-rays on Expression of Caspase-3 and p53 in EL-4 Cells and Its Biological Implications

Objective To investigate the effect of X-rays on expression of caspase-3 and p53 protein in EL-4 cells and its implications in induction of apoptosis and polyploid cells. Methods Mouse lymphoma cell line （EL-4 cells） was used. Fluorescent staining and flow cytometry analysis were employed for measurement of protein expression, apoptosis, cell cycle, and polyploid cells. Results The expression of caspase-3 protein increased significantly at 8 h and 12 h, compared with that of sham-irradiated control （P〈0.05, respectively） and the expression of p53 protein increased significantly at 2, 4, 8, 12, and 24 h, compared with that of sham-irradiated control （P〈0.05-P〈0.01） in EL-4 cells after 4.0 Gy X-irradiation. Apoptosis of EL-4 cells was increased significantly at 2, 4, 8, 12, 24, 48, and 72 h after 4.0Gy exposure, compared with that of sham-irradiated control （P〈0.05-P〈0.001）. G2 phase cells were increased significantly at 4, 8, 12, 24, 48, and 72 h （P〈0,05-P〈0.001）. However, no marked change in the number of 8 C polyploid cells was found from 2 to 48 h after 4.0 Gy exposure. Conclusion The expressions of caspase-3 and p53 protein in EL-4 cells are induced by X-rays, which might play an important role in the induction of apoptosis, and the molecular pathway for polyploid formation might be p53-independent.

Comparison Between X-rays Absorption and Emission Spectroscopy Measurements on a Ceramic Envelop Lamp

Burners of metal halide lamps used for illumination are generally made of polycrystalline alumina ceramic （PCA） which is translucent to visible light. We show that the difficulty of selecting a line of sight through the lamp prevents the use of optical emission diagnostic. X-rays photons are mainly absorbed and not scattered by PCA. Absorption by mercury atoms contributing to the discharge allowed us to determine the density of mercury in the lamp. By comparing diagnostic methods, we put in evidence the difficulty of taking into account the scattering of light mathematically.

Study of a solar flare on 2005 August 22 observed in hard X-rays and microwaves

We investigate the 2005 August 22 flare event（00：54 UT） exploiting hard X-ray（HXR） observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager（RHESSI） and microwave（MW） observations from the Nobeyama Solar Radio Observatory. The HXR time profile exposes well-damped quasi-periodic pulsations with four sequential peaks, and the MW time profile follows the corresponding peaks.Based on this feature, we derive the time relationship of HXRs and MWs with multifrequency data from the Nobeyama Radio Polarimeter, and the spatially resolvable data from RHESSI and the Nobeyama Radioheliograph. We find that both frequency dependent delays in MWs and energy dependent delays in HXRs are significant.Furthermore, MW emissions from the south source are delayed with respect to those from the north source at both 17 GHz and 34 GHz, but no significant delays are found in HXR emissions from the different sources at the same energies. To better understand all these long time delays, we derive the electron fluxes of different energies by fitting the observed HXR spectra with a single power-law thick-target model, and speculate that these delays might be related to an extended acceleration process. We further compare the time profile of a MW spectral index derived from 17 and 34 GHz fluxes with the flux densities, and find that the spectral index shows a strong anticorrelation with the HXR fluxes.

Chest X-rays in detecting injuries caused by blunt trauma

BACKGROUND:The appropriate sequence of different imagings and indications of thoracic computed tomography(TCT)in evaluating chest trauma have not yet been clarified at present.The current study was undertaken to determine the value of chest X-ray(CXR)in detecting chest injuries in patients with blunt trauma.METHODS:A total of 447 patients with blunt thoracic trauma who had been admitted to the emergency department(ED)in the period of 2009–2013 were retrospectively reviewed.The patients met inclusion criteria(age>8 years,blunt injury to the chest,hemodynamically stable,and neurologically intact)and underwent both TCT and upright CXR in the ED.Radiological imagings were re-interpreted after they were collected from the hospital database by two skilled radiologists.RESULTS:Of the 447 patients,309(69.1%)were male.The mean age of the 447 patients was 39.5±19.2(range 9 and 87 years).158(35.3%)patients were injured in motor vehicle accidents(MVA).CXR showed the highest sensitivity in detecting clavicle fractures[95%CI 78.3(63.6–89)]but the lowest in pneuomediastinum[95%CI 11.8(1.5–36.4)].The specificity of CXR was close to 100%in detecting a wide array of entities.CONCLUSION:CXR remains to be the first choice in hemodynamically unstable patients with blunt chest trauma.Moreover,stable patients with normal CXR are candidates who should undergo TCT if significant injury has not been ruled out.

Determination of Residuals Stresses Induced by the Autofrettage Treatment by the X-Rays Diffraction Method

Some meaningful advances have been made these last years to value precise and reliable way the residual stresses experimentally created by the autofrettage. The autofrettage process is used widely to introduce residual stresses into thick walled tubes;traditionally residual stresses have been measured using the Sachs method destructive or non-destructive methods. In this paper we describe the application of the X-rays diffraction;this technique permits to justify the presence of the compressive tangential residual stresses, and to value their distribution after two different autofrettage internal pressures loading. The results show that there is a large difference in the residual stresses find in the different autofrettege pressure. One can see the influence of the autofrettage’s pressure quantity on residual stresses created in the thickness of the test tubes.

Diagnostic Value of the Thoracic Ultrasonography Compared to Conventional Chest X-Rays in Pneumonia for Children between 0 to 15 Years: Case Study in Two Hospitals in Yaoundé

Introduction: The diagnosis of pneumonia is usually made based on clinical manifestations and chest X-ray. The use of ultrasound in detecting pulmonary diseases in general, and especially consolidation syndrome has been demonstrated. The objective of this study was to determine the accuracy of thoracic ultrasound compared to chest X-ray in the diagnosis of infectious pneumonia in children. Methods: Children between 0 to 15 years were included in our study. The lung ultrasound results obtained were compared with those of the chest X-ray used as the reference. Our data were introduced into the EpiInfo 3.5.4 software and analyzed with the EpiInfo 3.5.4 and IBMSPSS Statistics version 20.0 softwares. Microsoft Office Excel 2016 was used to produce Charts. Continuous quantitative variables were presented. Cohen’s Kappa concordance test was applied with confidence interval of 95%. Results: 52 children were enrolled in the study. In imaging, the dominant sign was consolidation syndrome (75.0%) of cases by chest radiography, and in 78.8% of cases by lung ultrasound (p Conclusion: Our study demonstrated that lung echography is a non-ionizing and reliable tool in the diagnosis of childhood’s pneumonia.

Exploration of computerized image processing in underexposed and overexposed X-rays of bones and joints

Objective: To study the effective computerized image processing of underexposed and overexposed X-rays of bones and joints. Methods: Ninety-nine conventional X-ray images (82 were overexposed and 17 were underexposed),scanned by an UMAX Astra 4000U Scanner, were converted into digital images on the basis of their analog images. A computerized imaging processing program consisting of five functional modules such as Contrast Stretch, Fast Flourier Transform (FFT), Image Smoothing Modules, Inverse Fast Flourier Transform (IFFT) and Nonlinear Transform performed image contrast stretch and smoothing. Three senior doctors from hospital image sections made their evaluation of all the processed images. Results: Of 82 overexposed films, 71 met the clinical requirements after image processing, and 11 were unable to be applied to clinical diagnosis, accounting for 87% and 13% respectively. Of the other 17 underexposed X-ray images, 11 met the clinical requirements while 6 were not, making a percentage of 64 and 35. Conclusion: Image contrast stretch and smoothing processing are significantly effective on conventional X-ray images which were inappropriately exposed, and can avoid more X-ray radiation caused by handling of radiological photograph again. This method can decrease hospital cost and provide acute and effective X-ray examinations for the treatment and cure for critical patients.

Focusing high-energy x-rays by a P MMA compound x-ray lens on Beijing synchrotron radiation facility

The x-ray compound lens is a novel refractive x-ray optical device. This paper reports the authors＇ recent research on a polymethyl methacrylate （PMMA） compound x-ray lens. Firstly the designing and LIGA fabrication process for the PMMA compound x-ray lens are briefly described. Then, a method for theoretical analysis, as well as the experimental system for measurement is also introduced. Finally, the focusing spots for 8keV monochromatic x-rays by the PMMA compound x-ray lens are measured and analysed. According to the experimental results, it is concluded that the PMMA compound x-ray lens promises a good focusing performance under the high-energy x-rays.

Poor Reproducibility in the Evaluation of Paranasal Sinus X-Rays in Chronic Rhinosinusitis

Objective: The aim of this study was to evaluate intra- and inter-observer reproducibility of sinus x-rays in comparison to sinus computed tomography (CT) in chronic rhinosinusitis (CRS) patients. Methods: This was a prospective controlled study for which 14 adult CRS patients were recruited. Patients underwent a sinus multi-detector CT scan as well as additional sinus x-rays at the same time. Symptom interview and skin prick tests were performed. Lund-Mackay (LM) scores and 43 other findings in paranasal sinuses were analyzed by three blinded observers from CT-scans and x-rays. We compared agreement between sinus CT and x-rays (intra-observer reproducibility) and between three observers (inter-observer reproducibility) by Cohen’s kappa. Results: In at least 90% of the cases, the status of 47/49 structures was detectable in CT scans, whereas the status of only 8/49 structures was detectable in x-rays. The majority of the 25 visualized structures had poor intra-observer and inter-observer reproducibility. Conclusion: Only a few structures can be visualized in paranasal sinus x-rays and compared to paranasal sinus CT-scans, their reproducibility is poor. Our results strongly support the current consensus of radiation dose reduction by limiting the number of x-rays.

X-Pinches as Broadband Sources of X-Rays for Radiography

Two methods of using the X-pinch as a source of X-ray radiation for radiography of biological objects are presented. X-pinches are found to be a very flexible method for generation of radiation over a wide spectral range and provide a high spatial and temporal resolution.