Signal enhancement ratio of multi-phase contrast-enhanced MRI: an imaging biomarker for survival in pancreatic adenocarcinoma.

OBJECTIVES: To evaluate signal enhancement ratio (SER) for tissue characterization and prognosis stratification in pancreatic adenocarcinoma (PDAC), with quantitative histopathological analysis (QHA) as the reference standard. METHODS: This retrospective study included 277 PDAC patients who underwent multi-phase contrast-enhanced (CE) MRI and whole-slide imaging (WSI) from three centers (2015-2021). SER is defined as (SIlt - SIpre)/(SIea - SIpre), where SIpre, SIea, and SIlt represent the signal intensity of the tumor in pre-contrast, early-, and late post-contrast images, respectively. Deep-learning algorithms were implemented to quantify the stroma, epithelium, and lumen of PDAC on WSIs. Correlation, regression, and Bland-Altman analyses were utilized to investigate the associations between SER and QHA. The prognostic significance of SER on overall survival (OS) was evaluated using Cox regression analysis and Kaplan-Meier curves. RESULTS: The internal dataset comprised 159 patients, which was further divided into training, validation, and internal test datasets (n = 60, 41, and 58, respectively). Sixty-five and 53 patients were included in two external test datasets. Excluding lumen, SER demonstrated significant correlations with stroma (r = 0.29-0.74, all p < 0.001) and epithelium (r = -0.23 to -0.71, all p < 0.001) across a wide post-injection time window (range, 25-300 s). Bland-Altman analysis revealed a small bias between SER and QHA for quantifying stroma/epithelium in individual training, validation (all within ± 2%), and three test datasets (all within ± 4%). Moreover, SER-predicted low stromal proportion was independently associated with worse OS (HR = 1.84 (1.17-2.91), p = 0.009) in training and validation datasets, which remained significant across three combined test datasets (HR = 1.73 (1.25-2.41), p = 0.001). CONCLUSION: SER of multi-phase CE-MRI allows for tissue characterization and prognosis stratification in PDAC. CLINICAL RELEVANCE STATEMENT: The signal enhancement ratio of multi-phase CE-MRI can serve as a novel imaging biomarker for characterizing tissue composition and holds the potential for improving patient stratification and therapy in PDAC. KEY POINTS: Imaging biomarkers are needed to better characterize tumor tissue in pancreatic adenocarcinoma. Signal enhancement ratio (SER)-predicted stromal/epithelial proportion showed good agreement with histopathology measurements across three distinct centers. Signal enhancement ratio (SER)-predicted stromal proportion was demonstrated to be an independent prognostic factor for OS in PDAC.

Outcomes of patients in nasopharyngeal adenoid cystic carcinoma in the IMRT era: a single-center experience.

OBJECTIVE: Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with special biological features. Controversies exist regarding the treatment approach and prognostic factors in the IMRT era. This study aimed to evaluate the long-term outcomes and management approaches in NACC. METHODS: Fifty patients with NACC at our institution between 2010 and 2020 were reviewed. Sixteen patients received primary radiotherapy (RT), and 34 patients underwent primary surgery. RESULTS: Between January 2010 and October 2020, a total of 50 patients with pathologically proven NACC were included in our analysis. The median follow-up time was 58.5 months (range: 6.0-151.0 months). The 5-year overall survival rate (OS) and progression-free survival rate (PFS) were 83.9% and 67.5%, respectively. The 5-year OS rates of patients whose primary treatment was surgery and RT were 90.0% and 67.3%, respectively (log-rank P = 0.028). The 5-year PFS rates of patients whose primary treatment was surgery or RT were 80.8% and 40.7%, respectively (log-rank P = 0.024). Multivariate analyses showed that nerve invasion and the pattern of primary treatment were independent factors associated with PFS. CONCLUSIONS: Due to the relative insensitivity to radiation, primary surgery seemed to provide a better chance of disease control and improved survival in NACC. Meanwhile, postoperative radiotherapy should be performed for advanced stage or residual tumours. Cranial nerve invasion and treatment pattern might be important factors affecting the prognosis of patients with NACC.

A Case report: Synovial sarcoma of the mediastinum in an 18-year-old teenager.

Synovial sarcomas (SSs) are a rare group of malignant tumors originating from pluripotential mesenchymal cells, which commonly occur as the primary tumor in the soft tissues near the articular surface, tendons, and articular synovium. Herein, we report a rare case of mediastinal SS in an 18-year-old teenager who initially presented with cough as the primary symptom. In this case, plain chest CT and contrast-enhanced CT clearly revealed the lesion presenting as a round-like and uneven density mass in the mediastinum with heterogeneous enhancement, which compressed the trachea and invaded the adjacent vessels. Based on the results of immunohistochemistry and fluorescence in situ hybridization (FISH), combined with the differential diagnosis with other types of tumors in the mediastinum on imaging, we were able to diagnose the tumor as an SS located in the mediastinum. Subsequent resection of the lesion coupled with chemotherapy and immunotherapy led to an improvement in the patient's symptoms.

A Combined Method of Seismic Monitoring and Transient Electromagnetic Detection for the Evaluation of Hydraulic Fracturing Effect in Coal Burst Prevention.

In order to mitigate the risk of roof-dominated coal burst in underground coal mining, horizontal long borehole staged hydraulic fracturing technology has been prevailingly employed to facilitate the weakening treatment of the hard roof in advance. Such weakening effect, however, can hardly be evaluated, which leads to a lack of a basis in which to design the schemes and parameters of hydraulic fracturing. In this study, a combined underground-ground integrated microseismic monitoring and transient electromagnetic detection method was utilized to carry out simultaneous evaluations of the seismic responses to each staged fracturing and the apparent resistivity changes before and after all finished fracturing. On this basis, the comparable and applicable fracturing effects on coal burst prevention were evaluated and validated by the distribution of microseismic events and their energy magnitude during the mining process. Results show that the observed mining-induced seismic events are consistent with the evaluation results obtained from the combined seismic-electromagnetic detection method. However, there is a limited reduction effect on resistivity near the fractured section that induces far-field seismic events. Mining-induced seismic events are concentrated primarily within specific areas, while microseismic events in the fractured area exhibit high frequency but low energy overall. This study validates the rationality of combined seismic-electromagnetic detection results and provides valuable insights for optimizing fracturing construction schemes as well as comprehensively evaluating outcomes associated with underground directional long borehole staged hydraulic fracturing.

Development of a radiomics-based model to predict occult liver metastases of pancreatic ductal adenocarcinoma: a multicenter study.

BACKGROUND: Undetectable occult liver metastases block the long-term survival of pancreatic ductal adenocarcinoma (PDAC). This study aimed to develop a radiomics-based model to predict occult liver metastases and assess its prognostic capacity for survival. MATERIALS AND METHODS: Patients who underwent surgical resection and were pathologically proven with PDAC were recruited retrospectively from five tertiary hospitals between January 2015 and December 2020. Radiomics features were extracted from tumors, and the radiomics-based model was developed in the training cohort using LASSO-logistic regression. The model's performance was assessed in the internal and external validation cohorts using the area under the receiver operating curve (AUC). Subsequently, the association of the model's risk stratification with progression-free survival (PFS) and overall survival (OS) was then statistically examined using Cox regression analysis and the log-rank test. RESULTS: A total of 438 patients [mean (SD) age, 62.0 (10.0) years; 255 (58.2%) male] were divided into the training cohort ( n =235), internal validation cohort ( n =100), and external validation cohort ( n =103). The radiomics-based model yielded an AUC of 0.73 (95% CI: 0.66-0.80), 0.72 (95% CI: 0.62-0.80), and 0.71 (95% CI: 0.61-0.80) in the training, internal validation, and external validation cohorts, respectively, which were higher than the preoperative clinical model. The model's risk stratification was an independent predictor of PFS (all P <0.05) and OS (all P <0.05). Furthermore, patients in the high-risk group stratified by the model consistently had a significantly shorter PFS and OS at each TNM stage (all P <0.05). CONCLUSION: The proposed radiomics-based model provided a promising tool to predict occult liver metastases and had a great significance in prognosis.

Synergistic effects of trace sulfadiazine and corrosion scales on disinfection by-product formation in bulk water of cast iron pipe.

The effects of trace sulfadiazine (SDZ) and cast-iron corrosion scales on the disinfection by-product (DBP) formation in drinking water distribution systems (DWDSs) were investigated. The results show that under the synergistic effect of trace SDZ (10 µg/L) and magnetite (Fe3O4), higher DBP concentration occurred in the bulk water with the transmission and distribution of the drinking water. Microbial metabolism-related substances, one of the important DBP precursors, increased under the SDZ/Fe3O4 condition. It was found that Fe3O4 induced a faster microbial extracellular electron transport (EET) pathway, resulting in a higher microbial regrowth activity. On the other hand, the rate of chlorine consumption was quite high, and the enhanced microbial EET based on Fe3O4 eliminated the need for microorganisms to secrete excessive extracellular polymeric substances (EPS). More importantly, EPS could be continuously secreted due to the higher microbial activity. Finally, high reactivity between EPS and chlorine disinfectant resulted in the continuous formation of DBPs, higher chlorine consumption, and lower EPS content. Therefore, more attention should be paid to the trace antibiotics polluted water sources and cast-iron corrosion scale composition in the future. This study reveals the synergistic effects of trace antibiotics and corrosion scales on the DBP formation in DWDSs, which has important theoretical significance for the DBP control of tap water.

Low Dose Iodinated Contrast Material and Radiation for Virtual Monochromatic Imaging in Craniocervical Dual-Layer Spectral Detector Computed Tomography Angiography: A Prospective and Randomized Study.

RATIONALE AND OBJECTIVES: To investigate the feasibility of virtual monochromatic imaging (VMI) of dual-layer spectral detector computed tomography (SDCT) to reduce iodinated contrast material (CM) and radiation dose in craniocervical computed tomography angiography (CTA). MATERIALS AND METHODS: A total of 280 consecutively selected patients performed craniocervical CTA with SDCT were prospectively selected and randomly divided into four groups (A, DoseRight index (DRI) 31, iopromide 370mgI/mL, volume 0.8 mL/kg; B, DRI 26, iopromide 370mgI/mL, volume 0.4 mL/kg; C, DRI 26, ioversol 320mgI/mL, volume 0.4 mL/kg; D, DRI 26, iohexol 300mgI/mL, volume 0.4 mL/kg). 50-70 kiloelectron volts (keV) VMIs in group B were reconstructed and compared to group A to select the optimal keV. Then, the optimal keV in groups B, C and D was reconstructed and compared. Objective image quality, including vascular attenuation, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), was evaluated. Subjective image quality was assessed using a 5-point Likert scale. In addition, the effective dose (ED), iodine load and iodine delivery rate (IDR) were compared between groups A and D. RESULTS: 55 keV VMI was the optimal VMI in group B. The objective and subjective image quality of 55 keV VMI in group B were equal to or better than those of the CI in group A. The SNR, CNR and subjective image quality in group D were similar to those in group B (P > 0.05). The ED, iodine load and IDR of group D were reduced by 44%, 59% and 19%, respectively, when compared to those of group A. CONCLUSION: Low dose iodinated CM and radiation for 55 keV VMI in craniocervical CTA using SDCT could still provide equivalent or better image quality than the conventional scanning protocol.

Nomogram Based on Dual-Layer Spectral Detector CTA Parameter for the Prediction of Infarct Core in Patients with Acute Ischemic Stroke.

(1) Background: Acute ischemic stroke (AIS) is time-sensitive. The accurate identification of the infarct core and penumbra areas in AIS patients is an important basis for formulating treatment plans, and is the key to dual-layer spectral detector computed tomography angiography (DLCTA), a safer and more accurate diagnostic method for AIS that will replace computed tomography perfusion (CTP) in the future. Thus, this study aimed to investigate the value of DLCTA in differentiating infarct core from penumbra in patients with AIS to establish a nomogram combined with spectral computed tomography (CT) parameters for predicting the infarct core and performing multi-angle evaluation. (2) Methods: Data for 102 patients with AIS were retrospectively collected. All patients underwent DLCTA and CTP. The patients were divided into the non-infarct core group and the infarct core group, using CTP as the reference. Multivariate logistic regression analysis was used to screen predictors related to the infarct core and establish a nomogram model. The receiver operating characteristic (ROC) curve, the calibration curve, and decision curve analysis (DCA) were used to evaluate the predictive efficacy, accuracy, and clinical practicability of the model, respectively. (3) Results: Multivariate logistic analysis identified three independent predictors: iodine density (OR: 0.022, 95% CI: 0.003-0.170, p < 0.001), hypertension (OR: 7.179, 95% CI: 1.766-29.186, p = 0.006), and triglycerides (OR: 0.255, 95% CI: 0.109-0.594, p = 0.002). The AUC-ROC of the nomogram was 0.913. Calibration was good. Decision curve analysis was clinically useful. (4) Conclusions: The spectral CT parameters, specifically iodine density values, effectively differentiate between the infarct core and penumbra areas in patients with AIS. The nomogram, based on iodine density values, showed strong predictive power, discrimination, and clinical utility to accurately predict infarct core in AIS patients.

The image quality and diagnostic performance of CT perfusion-derived CT angiography versus that of conventional CT angiography.

Background: The combination of computed tomography angiography (CTA) and computed tomography perfusion (CTP) evaluation of cerebral perfusion status and vascular conditions can improve the diagnostic accuracy of infarction, ischemia, and vascular occlusion in stroke patients, as well as a comprehensive assessment of cerebral edema, collateral circulation, and blood perfusion in the lesion area. However, the consequent radiation safety and contrast agent nephropathy have aroused increasing concern. The purpose of this study was to assess the image quality and diagnostic accuracy of CTA images derived from CTP data, and to explore the feasibility of replacing conventional CTA. Methods: A total of 31 consecutive patients with suspected acute ischemic stroke were retrospectively analyzed. All patients underwent head and neck CTA and brain CTP examinations. All the CTP images were transmitted to the ShuKun artificial intelligence system, which reconstructs CTA derived from CTP (CTA-DF-CTP). The images were divided into 2 groups, including CTA-DF-CTP (Group A) and conventional CTA (Group B). The CT attenuation values, subjective image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), image quality, CT volume dose index (CTDIvol), dose length product (DLP), and effective radiation dose (ED) were compared between the 2 groups. Moreover, the consistency of vascular stenosis and stenosis degree between the 2 groups were measured and evaluated. Results: There were no significant differences in image noise, SNR, or CNR between Groups A and B (P>0.05). The CT attenuation values of the arteries were higher in Group A than in B [internal carotid artery (ICA) =548±112 vs. 454±85 Hounsfield units (HU), middle cerebral artery (MCA) =453±118 vs. 388±70 HU, and basilar artery (BA) =431±99 vs. 360±83 HU] (P<0.01). The image quality of the 2 groups met the requirement of clinical diagnosis (4.97±0.18 vs. 4.94±0.25). No significant difference was found in subjective evaluation (P>0.05). In Group A compared with Group B, the following reductions were observed: CTDIvol (10.7%; 100.8 vs. 112.9 mGy), DLP (23.0%; 1,613±0 vs. 2,093±88 mGy·cm), and ED (23.0%; 5.00±0.00 vs. 6.49±0.27 mSv). Conclusions: CTA-DF-CTP data provide diagnostic accuracy and image quality similar to those of conventional CTA of head and neck CTA.

Sulfur-doped α-Fe2O3 as an efficient and recycled peroxydisulfate activator toward organic pollutant degradation: performance and mechanism.

Sulfur (S)-doped α-Fe2O3 has been regarded as an excellent catalyst for eliminating organic pollutants in the photo-Fenton-like reaction. Yet, the synthetic complexity and extremely low activity in the dark Fenton-like reaction still need to be solved. In this study, magnetic α-Fe2O3 with sulfide was successfully fabricated via hydrothermal and calcination processes, for the first time, where thiourea acted as both S source and reducing agent, and then, it was applied for activating peroxydisulfate (PDS) to degrade organic contaminants. Important influencing factors were systemically investigated, and the results showed that this catalyst activating PDS was highly effective in the removal of organic pollutants in dark- and photo-Fenton-like reactions. In addition, the catalyst possessed good stability and recyclable ability. The structure of catalyst was analyzed by several characterizations, such as XRD and XPS. The results revealed that sulfide had an important effect on the structure and performance of α-Fe2O3. The detected mechanism indicated that the main reactive oxygen species were altered after switching from darkness to LED illumination. This work offered a promising method to rationally design for S/α-Fe2O3 in the environmental remediation.

Exploring atherosclerosis imaging with contrast-enhanced MRI using PEGylated ultrasmall iron oxide nanoparticles.

Plaque rupture is a critical concern due to its potential for severe outcomes such as cerebral infarction and myocardial infarction, underscoring the urgency of noninvasive early diagnosis. Magnetic resonance imaging (MRI) has gained prominence in plaque imaging, leveraging its noninvasiveness, high spatial resolution, and lack of ionizing radiation. Ultrasmall iron oxides, when modified with polyethylene glycol, exhibit prolonged blood circulation and passive targeting toward plaque sites, rendering them conducive for MRI. In this study, we synthesized ultrasmall iron oxide nanoparticles of approximately 3 nm via high-temperature thermal decomposition. Subsequent surface modification facilitated the creation of a dual-modality magnetic resonance/fluorescence probe. Upon intravenous administration of the probes, MRI assessment of atherosclerotic plaques and diagnostic evaluation were conducted. The application of Flash-3D sequence imaging revealed vascular constriction at lesion sites, accompanied by a gradual signal amplification postprobe injection. T1-weighted imaging of the carotid artery unveiled a progressive signal ratio increase between plaques and controls within 72 h post-administration. Fluorescence imaging of isolated carotid arteries exhibited incremental lesion-to-control signal ratios. Additionally, T1 imaging of the aorta demonstrated an evolving signal enhancement over 48 h. Therefore, the ultrasmall iron oxide nanoparticles hold immense promise for early and noninvasive diagnosis of plaques, providing an avenue for dynamic evaluation over an extended time frame.

Synergetic effects of catalyst-surface dual-electric centers and microbes for efficient removal of ciprofloxacin in water.

Antibiotics and antibiotic resistance genes (ARGs) are still a problem in biological treatment. Herein, we propose a synergetic strategy between microbes and dual-electric centers catalysts (CCN/Cu-Al2O3/ceramsite) for Ciprofloxacin (CIP)-contained (5 mg/L) water treatment in an up-flow biological filter. CIP was cleaved into small molecules by the catalyst, bringing a 57.6% removal and reducing 10.5% ARG. The characterization results verified that a Cu-π electrostatic force occurs on the catalyst surface, forming electron-rich areas around Cu and electron-poor areas at the carbon-doped g-C3N4 (CCN) aromatic ring. Thus, the electrons of adsorbed CIP were delocalized and then captured by the adsorbed extracellular polymeric substance at the electron-rich areas. Therefore, the synergetic process weakened the stress of CIP on bacteria and reduced ARG accumulation. It also enriched more electro-active bacteria on the surface of CCN/Cu-Al2O3/ceramsite, promoting the expression of extracellular electron transfer-related genes and reconstructing the energy metabolism mode. This result provides an opportunity for refractory antibiotic treatment in the biological process.

[Mechanism of Salinization of Shallow Groundwater in Taocheng District, Hengshui City].

In order to understand the characteristics and origin of groundwater salinization in Taocheng district of Hengshui City, the recharge and salinization procession of shallow groundwater were analyzed with isotopic and geochemical data of the shallow groundwater (buried depth ≤ 100 m) and the soluble salt in boreholes. The results showed that the shallow groundwater was weak alkaline salt water, with the total dissolved solid (TDS) in the groundwater ranging from 176.06 to 17569.65 mg·L-1and the soil total salinity in unconsolidated sediments ranging from 1.830 to 6.509 g·kg-1. The hydrochemical types were mainly SO4·Cl-Na·Mg and Cl·SO4-Na·Ca in the shallow groundwater and the soluble salt. The main recharge resource of shallow groundwater was precipitation with different geological periods. The hydrochemical compositions of shallow groundwater mainly came from the dissolution of halite and sulfate weathering and experienced intense evaporation and the reduction environment. Meanwhile, the groundwater salinization was barely affected by human activities and seawater intrusion.

Purification mechanism of microbial metabolism in kitchen-oil wastewater enhanced by cationic vacancies on γ-Al2O3.

The use of catalyst materials to mediate the enhancement of microbial degradation in wastewater is a new economic and energy saving breakthrough in water treatment technology. In this study, γ-Al2O3, which is commonly used as catalyst/carrier, is used as biological filler to treat kitchen-oil wastewater with low biodegradability, and the COD removal rate is about 50 %. It is found that the complexation of cationic vacancies on Al2O3 surface with extracellular polymeric substance (EPS) secreted by microorganisms in wastewater lead to the polarization of electron distribution on biofilm. The efficient degrading bacteria are enriched on reaction interface and obtain electrons to maintain electron dynamic balance by enhancing the transmembrane metabolism of pollutants. The aluminum vacancies on Al2O3 surface accelerate the microbial degradation of pollutants. The cationic vacancies in the structure of catalyst accelerate the acquisition of exogenous electrons by microorganisms without the addition of external energy, which provides a new idea for catalytic fillers to enhance wastewater degradation.

T1 Mapping for Differentiating of Haemorrhagic Transformation from Extravasation of Iodine Contrast Agents: A Phantom Study.

OBJECTIVE: To evaluate T1 mapping values in different concentrations of iodine and mixed blood and to simulate the application of T1 mapping in differentiating iodine contrast extravasation and haemorrhage transformation after revascularisation in acute ischemic stroke. STUDY DESIGN: A phantom-based experimental study. Place and Duration of the Study: Department of Radiology, the Second Affiliated Hospital of Soochow University, China, from October 2020 to December 2021. METHODOLOGY: Fresh blood, pure iodine, blood-iodine mixtures (75/25, 50/50, and 25/75 ratios), and diluted iodine (at a concentration of 2.1 mmol I/L) were scanned in a phantom on 3-T MR T1 mapping imaging. A total of 10 layers in the middle section of tubes were scanned. The mean value of T1 mapping and 95% confidence interval for the investigated sample compositions were calculated and compared by ANOVA. RESULTS: The mean values (95% CI) for fresh blood, [2/3] blood +[1/3] iodine, [1/2] blood +[1/2] iodine, [1/3] blood +[2/3] iodine, and pure iodine were 2108.69 ± 1966.68-2250.71(ms), 1991.72 ± 1763.22-2220.21(ms), 1811.62 ± 1614.79-2008.45(ms), 1624.39 ± 1442.41-1806.37(ms), 1294.68 ± 1172.92-1416.44(ms), respectively. The differences between the T1 mapping values of all compositions were significant (p <0.01), except for fresh blood and the sample consisting of 67% blood. The mean value on T1 mapping (95% CI) was 1294.68 ± 1172.92-1416.44 (ms) in the samples only with diluted iodine, which was significantly different from other investigated samples (p <0.01). The intra-class correlation coefficient between the two times drawing of radiologist A was excellent (ICC=0.913, p<0.01), and between radiologists A and B was 0.99. CONCLUSION: Iodine contrast extravasation in a phantom setting might be distinguished from haemorrhagic transformation using T1 mapping. KEY WORDS: Acute ischemic stroke, Haemorrhage transformation, Contrast extravasation, Magnetic resonance imaging, T1 mapping, 3T MRI.

Energy spectrum CT index-based machine learning model predicts the effect of intravenous thrombolysis in lower limbs.

To develop a noninvasive machine learning (ML) model based on energy spectrum computed tomography venography (CTV) indices for preoperatively predicting the effect of intravenous thrombolytic treatment in lower limbs. A total of 3492 slices containing thrombus regions from 58 veins in lower limbs in a cohort of 18 patients, divided in good and poor thrombolysis prognosis groups, were analyzed. Key indices were selected by univariate analysis and Pearson correlation coefficient test. A support vector machine classifier-based model was developed through ten-fold cross validation. Model performance was assessed in terms of discrimination, calibration, and clinical usefulness at both per-slice and per-vessel levels. Continuous variables and categorical variables were compared between good and poor thrombolysis prognosis group by Mann-Whitney U-test and chi-square test, respectively. A nomogram was built by integrating clinical factors and the energy spectrum CTV index-based score calculated by the model. Six indices selected from 192 indices were used to build the predictive model. The ML model achieved area under the curves (AUCs) of 0.838 and 0.767 [95% CI (confidence interval), 0.825-0.850, 0.752-0.781] in the training and validation datasets at the per-slice level, and the per-vessel level AUCs were 0.945 and 0.876 (95% CI, 0.852-0.988, 0.763-0.948) in the training and validation datasets, respectively. The nomogram showed better performance with the per-vessel level AUC, accuracy, sensitivity and specificity, yielding 0.901(95% CI, 0.793-0.964), 86.2%, 87.9% and 84.0% in the validation dataset, respectively. There was no significant difference in the vessel distribution between good and poor thrombolysis prognosis groups (chi-square test, p = 0.671). The energy spectrum CTV index-based ML model achieved favorable effectiveness in predicting the outcome of vessel-level intravenous thrombolysis. A nomogram integrating clinical factors, and risk score calculated by the developed model showed improved performance and had potential to be used as a noninvasive preoperative tool for clinicians.

FeMoS2 micoroparticles as an excellent catalyst for the activation of peroxymonosulfate toward organic contaminant degradation.

The FeMoS2 catalyst for activating peroxymonosulfate (PMS) is a promising pathway for removing organic pollutants in wastewater, however, the dominant FeS2 phases and sulfur (S) vacancies in it are little involved. Herein, for the first time, novel bimetallic FeMoS2 microparticles were synthesized by a simple method and then applied for PMS activation for degrading organic pollutants. The catalysts were characterized by several techniques, including X-ray diffraction and X-ray photoelectron spectroscopies. The results revealed that new FeMoS2 microparticles containing S vacancies in the main FeS2 phases were obtained. FeS2 and S vacancies were found to play important roles for activating PMS by radical and nonradical pathways. More Fe2+ and Mo4+ were formed in the presence of S vacancies, which offered a new strategy for exploring novel heterogeneous catalysts in the activation of PMS for environmental remediation.

Radiomics model using preoperative computed tomography angiography images to differentiate new from old emboli of acute lower limb arterial embolism.

Our purpose was to devise a radiomics model using preoperative computed tomography angiography (CTA) images to differentiate new from old emboli of acute lower limb arterial embolism. 57 patients (95 regions of interest; training set: n = 57; internal validation set: n = 38) with femoral popliteal acute lower limb arterial embolism confirmed by pathology and with preoperative CTA images were retrospectively analyzed. We selected the best prediction model according to the model performance tested by area under the curve (AUC) analysis across 1,000 iterations of prediction from three most common machine learning methods: support vector machine, feed-forward neural network (FNN), and random forest, through several steps of feature selection. Then, the selected best model was also validated in an external validation dataset (n = 24). The established radiomics signature had good predictive efficacy. FNN exhibited the best model performance on the training and validation groups: its AUC value was 0.960 (95% CI, 0.899-1). The accuracy of this model was 89.5%, and its sensitivity and specificity were 0.938 and 0.864, respectively. The AUC of external validation dataset was 0.793. Our radiomics model based on preoperative CTA images is valuable. The radiomics approach of preoperative CTA to differentiate new emboli from old is feasible.

Evaluation of Anti-Burst Performance in Mining Roadway Support System.

The hazardous effect of a mine earthquake on a roadway is not only related to its energy scale but also to its distance from the roadway. In this study, a signal attenuation model and a disaster-causing model were established to evaluate the mine earthquake effects based on peak particle velocity (PPV) data recorded for 37221-1 upper roadway of the Dongxia Coal Mine, China. The characteristic of dynamic loads due to mine earthquake propagation to roadway surfaces was researched, and critical PPV values were identified using FLAC3D numerical simulation, which can be used to evaluate the roadway anti-burst performance under the existing support system. The results show that the support system is able to resist a mine earthquake with energy below 2.33 × 103 J; however, considering the energy accumulation volume of surrounding rocks and the range of source fracture, the maximum resistible mine earthquake energy can be up to 7.09 × 106 J when the roadway is 50 m away from the source. The validity and applicability of the disaster-causing models was verified by two rockburst cases that occurred during the excavation of the working face.

Sulfur vacancies on MoS2 enhanced the activation of peroxymonosulfate through the co-existence of radical and non-radical pathways to degrade organic pollutants in wastewater.

The enhancement of vacancies in catalysts involving Fenton-like reactions is a promising way to remove organic pollutants in wastewater, but sulfur vacancies are rarely involved. In this work, MoS2 containing defect sites were synthesized by a simple high-temperature treatment and then applied for activating peroxymonosulfate to eliminate organic pollutants in wastewater. The structure was characterized by several techniques such as XRD, BET, and XPS. Important influencing factors were systemically investigated. The results indicated that MoS2 with sulfur vacancies possessed a higher catalytic activity than that of the parent MoS2. The annealing temperature of the catalyst had a great effect on the removal of organic pollutants. Besides, the catalytic system had a wide pH range. Quenching and electron paramagnetic resonance (EPR) experiments indicated that the reaction system contained radical and non-radical species. The characterization results revealed that the defect sites in catalysts mainly strengthened the activity of catalysts. This study offers a new heterogeneous catalyst for the removal of organic pollutants via the peroxymonosulfate-based Fenton-like reactions.