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The outbreak of COVID-19 plunged the world into unprecedented difficulties, bringing life to a terrible standstill around the world and claiming thousands of lives. It seriously endangers human life and health. Thus, a high-efficiency COVID-19 and community-acquired pneumonia (CAP) detection method based on computed tomography (CT) images were developed to combat the pandemic. Sixty-one confirmed COVID-19 cases were consecutively enrolled together with 27 confirmed community-acquired pneumonia patients and 87 normal control patients with no finding of COVID-19 and CAP from Ruian People’s Hospital, from January 2020 to March 2020. The final cohort of 175 patients (1611 CT slices) was divided into training and test sets in an 8:2 and equal ratio. Three senior radiologists assessed clinical Characteristics of COVID-19 patients and abnormalities in chest CT images independently. The proposed model, EfficientNet-B1 was applied for the classification task, which consists of 16 mobile inverted bottleneck convolutions (MBConv), 2 convolutional (Conv) layers, 1 global average-pooling layer, and 1 fully connected layer, obtained a test accuracy of 94.24% and 93.64% for binary and three-class classification, respectively. It also achieved a sensitivity of 92.35%, a specificity of 95.93%, a positive predictive value of 95.26%, negative predictive value of 93.39% with an area under the receiver operating characteristic curve of 0.9414 for COVID-19 and CAP classification. Fever (58 [95.1%]) with a mean axillary temperature of 37.3 ± 0.8 °C, cough (52 [85.2%]), and sputum production (35 [57.4%]) are the most common symptoms of COVID-19 patients at the onset of illness. More importantly, more than 50% of COVID-19 images show ground-glass opacities. The proposed model achieves state-of-the-art performance and can be applied as a supplementary tool for radiologists, which is beneficial for pandemic control.

(1) Background: As a enrichment plant, ramie can be used for the phytoremediation of cadmium (Cd)-contaminated soil. However, it is worth exploring the role of plant growth regulators and foliar fertilizers in the process of plant growth and development and Cd adsorption. (2) Methods: By measuring the agronomic traits, Cd content of aboveground and underground ramie, calculating the Cd transfer coefficient (TF) and Cd bioconcentration factors (BCF), and the correlation between various indicators. This study examined the effects of plant growth regulators and foliar fertilizers on ramie’s capacity for Cd accumulation and transportation, (3) Results: Plant growth regulators and foliar fertilizers increased the Cd content of the aboveground ramie, reduced the Cd content of the underground ramie, and increased the TF. Among them, GA-1 increased the Cd content of the aboveground ramie to 3 times more than that of the control and reduced the Cd content of the underground ramie by 54.76%. Salicylic acid (SA) increased the Cd content of the aboveground ramie to 3 times more than that of the control. The combination of GA and foliar fertilizer reduced the Cd content of the aboveground and underground ramie and the TF and BCF of the underground ramie. After the hormones were sprayed, the TF of ramie had a significant positive correlation with the Cd content of the aboveground ramie; the BCF of the aboveground ramie had a significant positive correlation with the Cd content and TF of the aboveground ramie. (4) Conclusions: The results indicate that Brassinolide (BR), gibberellin (GA), ethephon (ETH), polyamines (PAs), and salicylic acid (SA) have different effects on the enrichment and transport of Cd in ramie. This study provided an effective method to improve the capacity for ramie to adsorb heavy metals during cultivation.

Silicon piezoresistive pressure sensors can only operate below 125 °C due to the leakage current of the PN junction. However, silicon-on-insulator (SOI) high-temperature pressure sensors use SiO2 for total dielectric isolation to solve this problem. At present, SOI high-temperature pressure sensors mostly use lead bonding package structure, with gold wire to lead the electrical signal and silicone oil as the protection medium, but the working temperature of silicone oil is limited to about 150 °C. In this paper, the leadless package structure is designed using pressure conduction on the backside of the chip and replacing the gold wire with sintered silver paste. The materials and dimensions of the leadless package structure are determined and then obtained a complete package structure through manufacturing. The reliability of the leadless package structure after silver paste sintering was verified by finite element analysis, and the results showed that the thermal stress caused by high and low-temperature cycles in the leadless package is minimal and does not affect the sensitivity of the pressure-sensitive chip. The size of the leadless package structure was optimized by Taguchi orthogonal method, and the maximum thermal stress was effectively reduced. Also, the key factors affecting the thermal stress of the leadless package in the package structure were identified by the variance number analysis method. The optimized leadless package structure size was remanufactured, and the sintered package structure was tested. The data show that the sensitivity of the pressure sensor is 30.82 mV/MPa with a nonlinearity of less than 0.4% full-scale (FS).

Biomedical image fusion is the process of combining the information from different imaging modalities to get a synthetic image. Fusion of phase contrast and green fluorescent protein (GFP) images is significant to predict the role of unknown proteins, analyze the function of proteins, locate the subcellular structure, and so forth. Generally, the fusion performance largely depends on the registration of GFP and phase contrast images. However, accurate registration of multi-modal images is a very challenging task. Hence, we propose a novel fusion method based on convolutional sparse representation (CSR) to fuse the mis-registered GFP and phase contrast images. At first, the GFP and phase contrast images are decomposed by CSR to get the coefficients of base layers and detail layers. Secondly, the coefficients of detail layers are fused by the sum modified Laplacian (SML) rule while the coefficients of base layers are fused by the proposed adaptive region energy (ARE) rule. ARE rule is calculated by discussion mechanism based brain storm optimization (DMBSO) algorithm. Finally, the fused image is achieved by carrying out the inverse CSR. The proposed fusion method is tested on 100 pairs of mis-registered GFP and phase contrast images. The experimental results reveal that our proposed fusion method exhibits better fusion results and superior robustness than several existing fusion methods.

Media-adventitia (MA) border delineates the outer appearance of arterial wall in intravascular ultrasound (IVUS) image. The detection of MA border is a challenging topic due to many difficulties such as complicated intravascular structures, intrinsic artifacts and image noises. We propose a classification-based MA border detection method with an embedded feature selection technique. The feature selection technique is based on Fractional-order Darwinian particle swarm optimization (FODPSO) algorithm. By employing feature selection, 293-dimension features including multi-scale features, gray-scale features and morphological feature are reducing to 37-dimension. The border detection method with feature selection is tested on a public dataset extracted from in-vivo pullbacks of human coronary arteries, which contains 77 IVUS images. Three indicators, Jaccard (JACC), Hausdorff Distance (HD) and Percentage of Area Difference (PAD), are measured for quantitative evaluation. Detection with 293-dimension features obtains JACC 0.79, HD 1.41 and PAD 0.16, while detection with 37-dimension features obtains JACC 0.83, HD 1.27 and PAD 0.12, indicating that the FODPSO-based feature selection method improves MA border detection by JACC 0.04, HD 0.14 and PAD 0.04. Furthermore, the proposed border detection method acquires better performances compared with two other automatic methods conducted on the same dataset available in literature.

Background Chest CT screening as supplementary means is crucial in diagnosing novel coronavirus pneumonia (COVID-19) with high sensitivity and popularity. Machine learning was adept in discovering intricate structures from CT images and achieved expert-level performance in medical image analysis. Methods An integrated machine learning framework on chest CT images for differentiating COVID-19 from general pneumonia (GP) was developed and validated. Seventy-three confirmed COVID-19 cases were consecutively enrolled together with 27 confirmed general pneumonia patients from Ruian People’s Hospital, from January 2020 to March 2020. To accurately classify COVID-19, region of interest (ROI) delineation was implemented based on ground-glass opacities (GGOs) before feature extraction. Then, 34 statistical texture features of COVID-19 and GP ROI images were extracted, including 13 gray-level co-occurrence matrix (GLCM) features, 15 gray-level-gradient co-occurrence matrix (GLGCM) features and 6 histogram features. High-dimensional features impact the classification performance. Thus, ReliefF algorithm was leveraged to select features. The relevance of each feature was the average weights calculated by ReliefF in n times. Features with relevance larger than the empirically set threshold T were selected. After feature selection, the optimal feature set along with 4 other selected feature combinations for comparison were applied to the ensemble of bagged tree (EBT) and four other machine learning classifiers including support vector machine (SVM), logistic regression (LR), decision tree (DT), and K-nearest neighbor with Minkowski distance equal weight (KNN) using tenfold cross-validation. Results and conclusions The classification accuracy (ACC), sensitivity (SEN), specificity (SPE) of our proposed method yield 94.16%, 88.62% and 100.00%, respectively. The area under the receiver operating characteristic curve (AUC) was 0.99. The experimental results indicate that the EBT algorithm with statistical textural features based on GGOs for differentiating COVID-19 from general pneumonia achieved high transferability, efficiency, specificity, sensitivity, and impressive accuracy, which is beneficial for inexperienced doctors to more accurately diagnose COVID-19 and essential for controlling the spread of the disease.

Purpose: Translocator protein (TSPO), an outer mitochondrial membrane protein, is regarded as a key biomarker for neuroinflammation in a variety of neurodegenerative diseases. In this study, we aim to evaluate two highly specific TSPO radiotracers [18F]VUIIS1009A and [18F]VUIIS1009B in a mild cerebral ischemic rat model, and to compare their in vivo performance to the well-established TSPO probe [18F]DPA-714 for neuroinflammation imaging. With multiple graphic analytical methods tested and macro parameters determined, we propose to find a suitable and best quantification method to profile neuroinflammation and measure TSPO density with the three TSPO radiotracers.Methods: Cerebral ischemia rat model was created and imaged using [18F]VUIIS1009A, [18F]VUIIS1009B and [18F]DPA-714. Displacement studies using non-radioactive analogs were performed to evaluate the binding specificities of [18F]VUIIS1009A and [18F]VUIIS1009B individually. Imaging analysis using arterial plasma input functions (AIFs) was employed to generate Logan plots and parametric images of total distribution volume (VT) for each radiotracer. Reference Logan model using contralateral brain as a reference region was introduced to generate parametric images for binding potential (BPND). Results: When compared to [18F]DPA-714, [18F]VUIIS1009B demonstrated higher binding potential (BPND) and distribution volume ratio (DVR). Parameter images of BPND and VT also indicate [18F]VUIIS1009B has a superior imaging profile with higher BPND and DVR when compared with other two radiotracers in TSPO imaging. Correlation analysis between BPND for [18F]VUIIS1009B and [18F]DPA-714 also indicates [18F]VUIIS1009B is more sensitive than [18F]DPA-714 in TSPO density measurement.Conclusions: This study demonstrates the superiority of [18F]VUIIS1009B to [18F]VUIIS1009A and [18F]DPA-714 in the neuroinflammation imaging. It also demonstrates that [18F]VUIIS1009B PET imaging coupled with parameter mapping (VT and BPND) and graphic analysis using Logan analysis and reference Logan analysis holds great promise for neuroinflammation characterization and TSPO density measurement.

Background: Thyroid nodules are commonly found at palpation amounting to 4–7% of the asymptomatic population and 50% of the cases are found at autopsy. Only a small proportion of thyroid nodules are malignant. The major challenge is the differential diagnosis of benign or malignant thyroid nodules, so we aim to develop the computer-assisted diagnostic method based on computed tomography (CT) images for thyroid lesions. Methods: In this study, we retrospectively collected 52 benign and 46 malignant thyroid nodules from 90 patients in CT examinations, together with the pathologist findings and radiology diagnosis. The first-order statistic and gray-level co-occurrence matrix features were extracted from thyroid computed tomography images. These texture features were used to assess the malignancy risk of the thyroid nodules. Several classification algorithms, including support vector machine, linear discriminant analysis, random forest, and bootstrap aggregating, were applied in the prediction. Leave-one-out cross-validation was used to evaluate the performance of thyroid cancer recognition. Results: In thyroid cancer identification based on a computed tomography image, we found the system using 17 texture features and support vector machine performed well. The accuracy, area under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, and negative predictive value, were 0.8673, 0.9105, 0.9130, 0.8269, 0.8235 and 0.9146, respectively. Conclusions: The proposed computer-aided diagnosis system provides a good assessment of the malignancy-risk of the thyroid nodules, which may help radiologists to improve the accuracy and efficiency of thyroid diagnosis.

Purpose:To investigate the feasibility of utilizing texture features to classify nodule from normal thyroid tissue in Computed Tomography (CT) images. Materials and Methods: Group A (negative) includes 152 normal thyroid CT images from 55 patients healthy controls enrolled in the study. Group B (positive) includes 134 thyroid images with nodules (50 malignant, 84 benign) of 58 patients undergone thyroid surgery and final diagnoses were confirmed by histopathology. Regions of interest (ROIs) from axial noncontrast CT images were delineated manually and 31 texture features including the gray level co-occurrence matrix (GLCM), the gray level gradient co-occurrence matrix (GLGCM), average intensity, contrast and coherence were extracted. Support Vector Machine (SVM) was used in data classification. Leave one out cross validation (LOOCV) strategy was utilized to take full advantage of the samples. To evaluate the performance of the proposed method, accuracyrate, sensitivity, specificity and area of under receiver operating characteristic (ROC) curve (AUC) etc. were calculated. Results: the accuracy-rate, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) are 0.8895±0.0186, 0.8265±0.0448, 0.9467±0.0141, 0.9340±0.0146 and 0.8586±0.0300 respectively, and the AUC is 0.9520±0.0089. Conclusion: Texture features can help radiologists to classify the nodule from normal thyroid tissue.

The potential problems of QA (quality assurance) and safety control of medical equipment in hospital were analyzed. On this base, this paper developed the testing system for the performance tests and the safety inspections of medical equipment in hospital, and discusses the results and the problems existing in the running systems.

Objectives Multifocal skeletal tuberculosis (MSTB) is an uncommon presentation of skeletal tuberculosis. In order to provide more clinically meaningful information on the diagnosis and management of MSTB, we present a case of MSTB with multiple tuberculous lesions in multiple locations, along with a review of 13 MSTB cases from different studies. Patients and methods A 29-year-old male patient with a one-year history of back pain was initially diagnosed with ankylosing spondylitis and arthritis deformans, and received treatment with oral glucocorticosteroid and leflunomide for 24 weeks. The back pain worsened with weight loss and fever one month prior to admission to our hospital. The diagnosis, MSTB, with 26 tuberculous lesions in 19 locations, was made by clinical findings, bone scan (computed topography and Tc-99m HDP scintigraphy), and bone marrow smear. Result Multiple antituberculous drugs, with supportive and immune-enhancing therapies cured the patient. Conclusions This case indicates that MSTB may develop in patients on long-term immunosuppressive drugs. In addition, our experience, along with previously reported data, suggest that strong clinical suspicion is required for an early diagnosis of MSTB, and chemotherapy, combined with supportive and immune-based therapies is effective for the treatment of MSTB.