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To explore added value of diffusion-weighted imaging (DWI) as an adjunct to Kaiser score (KS) for differentiation of benign from malignant lesions on breast magnetic resonance imaging (MRI).Two hundred forty-six patients with 273 lesions (155 malignancies) were included in this retrospective study from January 2015 to December 2019. All lesions were proved by pathology. Two radiologists blind to pathological results evaluated lesions according to KS. Lesions with score4 were considered malignant. Four thresholds of ADC values -1.3 × 10The AUC of KS was significantly higher than that of DWI alone (0.941 vs 0.901, p = 0.04). The sensitivity of KS (96.8%) and DWI (97.4 - 99.4%) was comparable (p0.05) while the specificity of KS (83.9%) was significantly higher than that of DWI (19.5-56.8%) (p0.05). Adding DWI as an adjunct to KS resulted in a 0-2.5% increase of specificity and a 0.1-1.3% decrease of sensitivity; however, the difference did not reach statistical significance (p0.05).KS showed higher diagnostic performance than DWI alone for discrimination of breast benign and malignant lesions. DWI showed no additional value to KS for characterizing breast lesions.• KS showed higher diagnostic performance than DWI alone for differentiation of benign from breast malignant lesions. • DWI alone showed a high sensitivity but a low specificity for characterizing breast lesions. • Diagnostic performance did not improve using DWI as an adjunct to KS.

A multifunctional semiconducting nanoagonist with high photothermic conversion efficiency (86.2%) and alkyl radical generation ability was developed. The nanoagonist demonstrated excellent anticancer performance through NIR-II light-triggered photothermic/thermodynamic combinational therapy both

Electric-field (EF) microsensors with high resolution are crucial for the realization of real-time dynamic status monitoring of Ubiquitous Power Internet of Things (UPIoT), which is of great significance for the safe operation of power system and early-stage diagnostics of power equipment. Distortion-free and high-resolution measurement of electric fields is also important in applications such as meteorological monitoring and aerospace launch. Existing electric-field measurement methods are always costly, bulky, and low in resolution. We presented a capacitive EF sensor with small size and high resolution. The presented sensor is based on piezoelectric effect, and a micro cantilever structure is realized using microfabrication. Simulation and experimental results indicate that the presented sensor has a resolution of about 45 V/m and a measurable magnitude of over 1.5 MV/m. Owing to the characteristics of small size, low cost and low power consumption, the EF sensor is suitable for applications of large-scale sensing arrays.

Background The aim of the present study was to explore the brain active characteristics of patients with irritable bowel syndrome with diarrhea (IBS-D) using resting-state functional magnetic resonance imaging technology. Methods Thirteen IBS-D patients and fourteen healthy controls (HC) were enrolled. All subjects underwent head MRI examination during resting state. A voxel-based analysis of fractional amplitude of low frequency fluctuation (fALFF) maps between IBS-D and HC was performed using a two-sample t-test. The relationship between the fALFF values in abnormal brain regions and the scores of Symptom Severity Scale (IBS-SSS) were analyzed using Pearson correlation analysis. Results Compared with HC, IBS-D patients had lower fALFF values in the left medial superior frontal gyrus and higher fALFF values in the left hippocampus and right precuneus. There was a positive correlation between the duration scores of IBS-SSS and fALFF values in the right precuneus. Conclusion The altered fALFF values in the medial superior frontal gyri, left hippocampus and right precuneus revealed changes of intrinsic neuronal activity, further revealing the abnormality of gut-brain axis of IBS-D.

BACKGROUND Pulmonary tumorlets are nodular hyperplastic neuroendocrine cells (NECs) that extend beyond the basement membrane. They often coexist with other lung diseases such as fibrosis and bronchiectasis, but rarely accompanied by pulmonary sclerosing pneumocytoma (PSP), which has not been reported in the literature. CASE SUMMARY A 54-year-old woman was admitted to the hospital because she had symptoms of bloody sputum for more than 4 mo and hemoptysis for 1 wk. Computed tomography images showed atrophy accompanied by infections in the middle lobe of her right lung. Moreover, numerous nodules were identified in the middle lobe of the right lung. The patient underwent thoracoscopic pneumonectomy of the middle lobe of the right lung, and the resected mass was pathologically confirmed to have bronchiectasis, multifocal NEC hyperplasia accompanied by tumorlet, and PSP. CONCLUSION Our report presents a rare clinical case of bronchiectasis complicated with multifocal NEC hyperplasia, tumorlet, and PSP.

Background Umbilical cord-derived mesenchymal stem cell (UCMSCs) transplantation has been widely studied in premature ovarian failure (POF). However, the underlying mechanism remains elusive. This study aims to investigate the protective properties and mechanisms of heme oxygenase-1 (HO-1) expressed in UCMSCs in restoring the ovarian function of POF mice. Methods In in vitro and in vivo experiments, mice were treated with the presence or absence of the HO-1/shHO-1-transfected UCMSCs, and the administration of SP600125 or anisomycin, the inhibitor or activator of JNK. The viability and apoptosis of granulosa cells (GCs) at different time points of co-cultivation were assessed in vitro. In in vivo experiments, mouse ovarian function was assessed by detecting the serum levels of hormone and observing the ovarian morphological changes. Multiple molecular indices of JNK/Bcl-2 signal pathway were performed. And the autophagy changes in GCs were assessed by detecting the associated cytokines and observing the intracellular autophagosome accumulation. Additionally, the spleen levels of CD8+CD28− T cells and serum levels of interleukin 10 (IL-10) were tested to evaluate the immune mechanisms involved. Results UCMSCs transfected with shHO-1 or treated with SP600125 inhibited GCs’ viability and promoted its apoptosis in a time-dependent manner in vitro. In in vivo experiments, mice in both groups showed little therapeutic efficiency which presented as the increased extent of ovarian fibrosis with decreased number of functional follicles, and disordered hormone production. Additionally, the JNK/Bcl-2-associated cytokines were obviously declined. The inhibited autophagy-related cytokines, the chromatin condensation and abound vacuolar autophagosome in GCs, and weakened fluorescence intensity by MDC were observed. The downregulated levels of CD8+CD28− T cells and serum levels of IL-10 were also detected. The damages above can be alleviated with HO-1-MSCs treatment or anisomycin administration. Conclusions HO-1 expressed in UCMSCs is critical in restoring the ovarian function in POF mice with UCMSC transplantation, which is mediated by the activation of JNK/Bcl-2 signal pathway-regulated autophagy and upregulating the circulating of CD8+CD28− T cells.

Electric power sensing devices and networks have become one of the most important infrastructures of smart grids. As a basic component of smart grids, there is an urgent need to develop non-contact, wide-range, wide-band and low-cost miniature electric field sensors. This paper proposes a micro electric field sensor based on luminous flux sensing device deformation. The mathematical theory and finite element simulation software are used to predict and evaluate the sensing performance. The influence of each parameter on the performance of the device is analyzed as well. Experiment results show that the sensor, can achieve a stably electric field measure at a range of 19 kV/m - 10.62 MV/m, and has a frequency bandwidth of 71 Hz with 3 dB attenuation. Besides, it has the advantages of high sensitivity, high measurement accuracy, low cost and very limited interference from stray capacitance. It can realize the measurement of DC and AC power frequency electric fields.

Background: The coronavirus disease 2019 (COVID-19) has brought a global disaster. Quantitative lesions may provide the radiological evidence of the severity of pneumonia and further to assess the effect of comorbidity on patients with COVID-19.Methods: 294 patients with COVID-19 were enrolled from February, 24, 2020 to June, 1, 2020 from six centers. Multi-task Unet network was used to segment the whole lung and lesions from chest CT images. This deep learning method was pre-trained in 650 CT images (550 in primary dataset and 100 in test dataset) with COVID-19 or community acquired pneumonia and Dice coefficients in test dataset were calculated. 50 CT scans of 50 patients (15 with comorbidity and 35 without comorbidity) were random selected to mark lesions manually. The results will be compared with the automatic segmentation model. Eight quantitative parameters were calculated based on the segmentation results to evaluate the effect of comorbidity on patients with COVID-19.Results: Quantitative segmentation model was proved to be effective and accurate with all Dice coefficients more than 0.85 and all accuracies more than 0.95. Of the 294 patients, 52 (17.7%) patients were reported having at least one comorbidity, 14 (4.8%) having more than one comorbidity. Patients with any comorbidity were older (PPPPPConclusions: Multi-task Unet network can make quantitative CT analysis of lesions to assess the effect of comorbidity on patients with COVID-19, further to provide the radiological evidence of the severity of pneumonia. More lesions (including GGO and consolidation) were found in CT images of cases with comorbidity. The more comorbidities patients have, the more lesions CT images show.

UHV DC line arrester long length, there is a significant electric field distribution uniformity. This paper establishes a simulation analysis model for the electric field distribution of the UHV DC line arrester, and systematically studies the influence of measures such as adjusting the structure and the dielectric constant of the arrester valve disc on the electric field distribution of the arrester. It shows that the combination of different dielectric constants of arrester valves can significantly improve the electric field distribution of the arresters in UHV DC lines.

When the Ultra High Voltage Direct Current (UHV DC) line is struck by lightning, it may cause the protection action of the DC system. In this paper, a simulation analysis model of the lightning transient process of UHV DC line is established, and the influence of the line arrester and its installation position and quantity on the protection action is systematically studied. The research results show that line arresters can reduce the impact of lightning overvoltage on UHV DC system protection and prevent lightning strikes from causing DC system protection under certain conditions. The more line arresters are installed along the line, the more significant the effect.

Background The coronavirus disease 2019 (COVID-19) is a pandemic now, and the severe COVID-19 determines the management and treatment, even prognosis. Thus, we aim to develop and validate a radiomics nomogram for identifying severe patients with COVID-19.Methods There were 156 and 104 patients with COVID-19 enrolled in primary and validation cohorts respectively. Radiomics features were extracted from chest CT images. Least absolute shrinkage and selection operator (LASSO) method was used for feature selection and radiomics signature building. Multivariable logistic regression analysis was used to develop a predictive model, and the radiomics signature, abnormal WBC counts, and comorbidity were incorporated and presented as a radiomics nomogram. The performance of the nomogram was assessed through its calibration, discrimination, and clinical usefulness.Results The radiomics signature consisting of 4 selected features was significantly associated with clinical condition of patients with COVID-19 in the primary and validation cohorts (P Conclusions We present an easy-to-use radiomics nomogram to identify the severe patients with COVID-19 for better guiding a prompt management and treatment.

Background:Castleman's disease (CD) is an uncommon type of benign proliferation of the lymphoid tissue.The occurrence of CD in the liver is rare. Radiological diagnosis of hepatic CD by computed tomography (CT) and magnetic resonance imaging (MRI) remains difficult. It is difficult to distinguish between CD of the liver and hypervascular liver tumors such as focal nodular hyperplasia (FNH) and hepatocellular adenoma before surgery.Case presentation: We report a unique case of CD in the hepatis cauda lobe in a 26-year-old young woman after a health checkup,abdominal ultrasonography, CT and MRI results showed a 5 cm×3 cm sized hypervascular mass. The patient was diagnosed as CD by histologic examination. The liver mass showed the imaging feature of central low density or signal enhancement in the arterial phase on contrast-enhanced CT and MRI, the tortuous access vessel could be seen in the lesion. The tumor became homogeneous isodense or isointense to the surrounding liver tissues during the portal phase. Dffusion restriction demonstrated on MRI. All these imaging findings, which might be useful clues for identifying CD in the liver.The patient underwent complete resection of the tumor. The patient was followed-up without any further treatment and the disease has shown no signs of recurrence.Conclusions:Primarily hepatic CD without lymph node hyperplasia or clinical symptoms is extraordinarily rare and different from other hypervascular liver tumors. Therefore, it is extremely important to improve the awareness of this diagnosis. Attention should be paid to the difference hepatic CD between FNH, hepatocellular adenoma, lymphoma and so on. To avoid misdiagnosis with unnecessary surgical excision, distinguishing these diseases is crucial.

Background The novel coronavirus pneumonia (coronavirus disease 2019, COVID-19) has spread around the world. We aimed to recapitulate the clinical and CT imaging features of COVID-19 and their differences in three age groups. Methods The clinical and CT data of patients with COVID-19 (n = 307) that had been divided into three groups (Group 1: Results Of all patients, 114 (37.1%) had histories of epidemiological exposure, 48 (15.6%) were severe/critical cases, 31 had hypertension (10.1%), 15 had diabetes mellitus (4.9%), 3 had chronic obstructive pulmonary disease (COPD, 1%). Among the three groups, severe/critical type, hypertension and diabetes occurred more commonly in the elderly group compared with Group 1&2 (P P P P Conclusions COVID-19 presented representative clinical manifestations, laboratory examinations and CT findings, but three age groups possessed their own specific characteristics. Grasping the clinical and CT features stratified by age will be helpful for early definite diagnosis of COVID-19.

Purpose: To explore the value of the apparent diffusion coefficient (ADC) in assessing preoperative T staging of low rectal cancer and the correlation between ADC value and Ki-67 expression. Methods: Data on 77 patients with a proven pathology of low rectal cancer were retrospectively analyzed. All patients underwent a magnetic resonance imaging scan 1 week prior to operation, and the mean ADC value was measured. All tumors were fully removed, and pathologic staging was determined. The Ki-67 expression was determined using immunohistochemical methods in all patients. The correlation between Ki-67 expression and ADC features was studied. Results: A total of 77 patients with low rectal cancer were included in the study. The pathology type was adenocarcinoma. The numbers of patients with pathological stages T1, T2, T3, and T4 were 9, 23, 32, and 13, respectively. The ADC value of all tumors ranged from 0.60 to 1.20 mm2/s. The average Ki-67 proliferation index was 55.3% ± 20.2%. A significant difference was observed between the preoperative ADC value and pathological T staging of low rectal cancer ( P < .01). The more advanced the T stage, the lower the detected ADC values were. A negative correlation was noted between the preoperative ADC value and Ki-67 proliferation index of rectal cancer ( r = −0.71, P < .01). When the Ki-67 proliferation index increased, lower ADC values were detected. Conclusion: The ADC values can provide useful information on preoperative tumor staging and may facilitate evaluation of the biological behavior of low rectal cancer. The ADC values should be considered a sensitive image biomarker of rectal cancer.

A 16-year-old boy was admitted to our hospital due to sudden pale face and chest pain for half-an-hour. He could not express properly because of hypophrenia. Other examinations revealed congenital cataract in the right eye, as well as nystagmus and generalized hypotonia. He had signs of ataxia, and, though without deformity in any limb, was unable to complete the straight-line walking test. Five years ago, the boy was abandoned to a welfare home. The caretaker of the welfare home complained that the boy had several times of episodic hyperpnea, every 1–2 h, each lasting for about 10–40 s, during the night sleep. Ultrasonography of liver, cholecyst, pancreas, spleen, kidney and heart showed no abnormal findings. Electrocardiogram showed sinus arrhythmia.

Energy, information, and materials are the three main factors required for the survival and development of modern humankind, with energy being the cornerstone of all development. In recent years, self-powered devices have received widespread attention. As a new generation device, Triboelectric nanogenerators (TENGs) assembled from flexible materials possess the characteristics of flexible design, low-cost, stable output performance, etc., and can be widely used in wearable and self-powered medical detection sensors of human body. In this paper, flexible bromobutyl rubber (BIIR) and PET were used as friction materials, and assembled into arched vertical contact-separation triboelectric nanogenerators following various film formation and surface roughening treatments. The treatment and assembly methods of the friction materials were studied in order to obtain the best power generating effects. In addition, due to the biocompatibility and intrinsic antibacterial property of BIIR films, the fabricated triboelectric nanogenerator was also applied to wearable self-powered sensor equipment, proving its potential in the fields of identification and gait analysis.

Oral administration of nanoparticles is extremely limited due to the two processes of mucus permeation and epithelial absorption, which requires completely opposite surface properties of the nanocarriers. To tackle the contradiction, we developed a rational strategy to modify the surface of mesoporous carbon nanoparticles with chitosan concealed by a hydrophilic N-(2-hydroxypropyl) methacrylamide copolymer (pHPMA) layer. Probucol (PB) with the low poor permeability and solubility was loaded in optimal nanocarriers to realize the high loading efficacy and controlled release. The pHPMA polymer is a hydrophilic "mucus-inert" material, which could be dissociable from the surface of nanoparticles in the mucus, thus promoting their mucus permeation and causing exposure of chitosan in transepithelial transport. The swelling effect of chitosan under acidic conditions allowed regulation of PB release behavior. In conclusion, the mucus-permeable nanocarrier could effectively overcome multiple gastrointestinal absorption barriers and the oral bioavailability of PB-loaded HCMCN was 2.76-fold that of commercial preparation.

Rationale: Malignant melanoma predominantly develops in middle-aged and older adults, most commonly occurring on the skin and rarely on internal organs. Malignant melanoma originating in the liver is extremely rare. Imaging findings of primary hepatic melanoma (PHM) are scarce in relevant literature. Patient concerns: The patient was a 69-year-old woman from Zhejiang, China, who was admitted to the hospital because of upper abdominal pain that persisted for >10 days. Diagnoses: Computed tomography (CT) findings indicated the presence of a circular low-density shadow of approximately 7.5 × 8.0 cm in the hepatic hilar region. Magnetic resonance imaging (MRI) indicated a heterogeneous solid cystic mass in the hepatic hilar region. The mass exhibited heterogeneous low-signal intensity on a T1-weighted image (T1WI) and slightly higher signal intensity on a T2-weighted image (T2WI). The tumor appeared as multiple irregular strips with high-signal intensity on T1WI and low-signal intensity on T2WI. The diffusion-weighted image revealed increased signal intensity. The tumor continued to be enhanced after enhancement. Clinical data suggested that the tumor was a malignant liver tumor. Interventions: The patient underwent a CT guide puncture hepatic biopsy. The tumor was located in the hepatic hilar region adjacent to the large blood vessels and invaded the portal vein. Because a resection was highly risky, conservative treatment was conducted. Outcomes: Postoperative pathology and clinical examination confirmed that the tumor was malignant PHM. The patient has been followed up for 6 months. The patient underwent CT reexamination 2 months after conservative treatment, the results of which revealed that the tumor progressed. Multiple lesions were identified; moreover, the tumor size had increased and the tumor had invaded the portal vein and intrahepatic bile duct. The patient was reexamined by CT in another hospital 6 months after conservative treatment. The results revealed peritoneal, omental metastases and multi bone metastases. Lessons: To our best knowledge, this is the first reported case of a PHM with complete imaging data, including preoperative CT and MRI examinations and a follow-up CT examination. From compiling the CT and MRI findings of this patient and those of relevant studies, this study can serve as a reference for the preoperative diagnosis and differential diagnosis of PHM.

To retrospectively analyze the computed tomography (CT) findings and clinical manifestations of gastric calcifying fibrous tumor (CFTs). The features of 7 cases with pathologically proven gastric CFTs who had undergone CT were assessed, including tumor location, contour, growth, degree of enhancement, calcification and clinical data. In addition, the size and CT value of each lesion were measured. The mean values of these CT findings and clinical data were statistically analyzed only for continuous variables. Four patients were female and three were male (mean age: 33.3 years; range: 22 ∼ 47 years). Nonspecific clinical symptoms: abdominal pain and discomfort were observed in four cases and the CFTs were incidentally detected in the other three cases. Regarding tumor markers, lower ferritin levels were observed in three female patients. All of the gastric CFTs were solitary and mainly located inside the body; they were in round or oval shape and exhibited endophytic growth. Gastric CFTs are usually small sized and could contain confluent and coarse calcifications; cyst, necrosis, ulcer, bleeding and surrounding lymphadenopathy were not found in any of the cases. Unenhanced CT values of gastric CFTs were higher than those of same-transect soft tissue. Mild-to-moderate enhancement in the arterial phase and progressive enhancement in the portal venous phase were mainly noted. A gastric mass with a high unenhanced CT attenuation value, confluent and coarse calcifications and mild-to-moderate enhancement could prompt a diagnosis of gastric CFT. In addition, (1) being young- or middle-aged, (2) having relatively low ferritin levels, and (3) tumor located in the gastric body have critical reference value for diagnosis of gastric CFT.

Millirobots are a promising robotic platform for many applications due to their small size and low manufacturing costs. Legged millirobots, in particular, can provide increased mobility in complex environments and improved scaling of obstacles. However, controlling these small, highly dynamic, and underactuated legged systems is difficult. Hand-engineered controllers can sometimes control these legged millirobots, but they have difficulties with dynamic maneuvers and complex terrains. We present an approach for controlling a real-world legged millirobot that is based on learned neural network models. Using less than 17 minutes of data, our method can learn a predictive model of the robot's dynamics that can enable effective gaits to be synthesized on the fly for following user-specified waypoints on a given terrain. Furthermore, by leveraging expressive, high-capacity neural network models, our approach allows for these predictions to be directly conditioned on camera images, endowing the robot with the ability to predict how different terrains might affect its dynamics. This enables sample-efficient and effective learning for locomotion of a dynamic legged millirobot on various terrains, including gravel, turf, carpet, and styrofoam. Videos and further details can be found at https://sites.google.com/view/imageconddyn

Rationale Intrauterine devices (IUDs) are one of the most common and effective methods of contraception worldwide. Migration of an IUD to an extrauterine site is a rare complication. The aim of this study was to report an extremely rare case in which an IUD was found in an ovarian tumor. Patient concerns A 63-year-old Chinese woman presented with vaginal bleeding and lower abdominal pain during hospitalization due to pneumonia. Preoperative imaging showed bilateral cystic masses in the adnexal region, and ring hyperdensity was found in the right ovarian mass. Endometrial thickening and multiple uterine leiomyomas were found on ultrasonography. Hysteroscopy showed partial septate uterus and a small endometrial polyp. Diagnosis Bilateral ovarian cystadenomas with perforation of the IUD into the right ovarian tumor were considered based on preoperative imaging and the patient's medical history. Furthermore, early endometrial carcinoma was suspected. Interventions The patient underwent hysterectomy, bilateral salpingo-oophorectomy, and omentectomy. A stainless steel ring IUD was confirmed within the right ovarian tumor during the operation. Outcomes The pathology results demonstrated bilateral ovarian serous cystadenofibromas with focal epithelial proliferation and endometrial atypical hyperplasia with malignant transformation. The patient has been followed up for 7 months, and there has been no recurrence at present. Lessons The presence of an IUD within an ovarian tumor is extremely rare. This is the second reported case in the English literature describing an extrauterine IUD within an ovarian tumor. The correlation between ovarian cancer tumorigenesis and IUD translocation is unclear and requires further investigation.

Epidemiological studies show a positive correlation between the air levels of fine particulate matter (PM2.5) and cardiovascular disorders, but how PM2.5 affects cardiomyocytes has not been studied in great deal. The aim of the present study was to obtain an insight into the links among intracellular levels of reactive oxygen species (ROS), apoptosis and mitogen-activated protein kinases (MAPKs) in rat cardiac H9c2 cells exposed to PM2.5. H9c2 cells were incubated with PM2.5 at 100-800 µg ml(-1) to evaluate the effects of PM2.5 on cell viability, cell apoptosis, intracellular levels of ROS and expression of apoptosis-related proteins as well as activation of MAPKs. PM2.5 decreased cell viability, increased the cell apoptosis rate and intracellular ROS production in a concentration-dependent manner. PM2.5 decreased the Bcl-2/Bax ratio and increased cleaved caspase-3 levels. A Western blots study showed up-regulation of phosphorylated MAPKs including extracellular signal-regulated protein kinases (ERKs), c-Jun NH2-terminal kinases (JNKs) and p38 MAPK in the PM2.5-treated cells. The p38 MAPK inhibitor SB239063 attenuated whereas the ERKs inhibitor PD98059 augmented the effects of PM2.5 on apoptosis and the expression of related proteins. In conclusion, PM2.5 decreases cell viability and increases apoptosis by enhancing intracellular ROS production and activating the MAPKs signaling pathway in H9c2 cells. The MAPKs signaling pathway could be a new promising target for clinical therapeutic strategies against PM2.5-induced cardiac injury.

The Maxwell equations as a fundamental equation governing the electromagnetic fields are investigated. Several ideal systems of parallel plate capacitor with various dielectric mediums are discussed. By considering these cases, the boundary conditions in the process of solving the equations and the separation of variables as a primary method to solve the equations are studied, which will be the foundation of our future work.

An analytical model has been developed for analyzing the braking torque in electromagnetic retarder by flux tube and armature reaction method. The magnetic field distribution in air gap, the eddy current induced in the rotor and the braking torque are calculated by the developed model. Two-dimensional and three-dimensional finite element models for retarder have also been developed. Results from the analytical model are compared with those from finite element models. The validity of these three models is checked by the comparison of the theoretical predictions and the measurements from an experimental prototype. The influencing factors of braking torque have been studied.