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1.
Neural Netw ; 176: 106324, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38657421

ABSTRACT

Generalized zero-shot learning (GZSL) aims to recognize both seen and unseen classes, while only samples from seen classes are available for training. The mainstream methods mitigate the lack of unseen training data by simulating the visual unseen samples. However, the sample generator is actually learned with just seen-class samples, and semantic descriptions of unseen classes are just provided to the pre-trained sample generator for unseen data generation, therefore, the generator would have bias towards seen categories, and the unseen generation quality, including both precision and diversity, is still the main learning challenge. To this end, we propose a Prototype-Guided Generation for Generalized Zero-Shot Learning (PGZSL), in order to guide the sample generation with unseen knowledge. First, unseen data generation is guided and rectified in PGZSL by contrastive prototypical anchors with both class semantic consistency and feature discriminability. Second, PGZSL introduces Certainty-Driven Mixup for generator to enrich the diversity of generated unseen samples, while suppress the generation of uncertain boundary samples as well. Empirical results over five benchmark datasets show that PGZSL significantly outperforms the SOTA methods in both ZSL and GZSL tasks.

2.
Sci Rep ; 13(1): 20753, 2023 Nov 25.
Article in English | MEDLINE | ID: mdl-38007510

ABSTRACT

Rock burst disaster affects underground mining safety. The energy-absorbing hydraulic support for preventing tunnel impact has been implemented in rock burst mines. In order to compare the impact resistance characteristics of conventional columns and energy-absorbing columns, based on the derivation of energy theory, the CEL fluid-solid coupling simulation algorithm is used to simulate the process of static load 1000 kN superimposed impact load 1500 kN on φ180 mm type conventional column and energy-absorbing column. Combined with the static-dynamic combined test of the 6500 kN impact testing machine on the column, the accuracy and reliability of the CEL simulation column impact response are verified. The results showed that compared with conventional columns, the reaction force of energy-absorbing columns is reduced by 32.55%. The stress and expansion of the cylinder are significantly reduced. The acceleration of the mass movement has been reduced by 59.46%. The addition of the energy-absorbing device enhances the system's energy absorption by 33.46%, thereby reducing the energy absorption of the column itself to 23.58%. Additionally, the deformation of the energy-absorbing device increases the effective displacement by 239.45%. This also prolongs the impact duration, ensuring sufficient time for the safety valve to open, safeguarding the support from damage, and enhancing the overall integrity of the tunnel.

3.
BMC Psychiatry ; 23(1): 813, 2023 11 07.
Article in English | MEDLINE | ID: mdl-37936100

ABSTRACT

BACKGROUND: Previous studies on bedtime procrastination mainly focused on the influencing factors of stress and draw less attention on the role of family environment. AIM: This study aimed to explore the effect of psychological stress reaction on bedtime procrastination in young adults, with considering the mediating effect of smartphone addiction, and the moderating effect of family cohesion during the COVID-19 pandemic. METHODS: A sample of 1217 young adults completed psychological stress reaction scale, Smartphone addiction tendency scale for young adults, bedtime procrastination scale and family cohesion scale. A moderated mediation model was conducted to clarify the effect of psychological stress reaction on bad bedtime procrastination in young adults. RESULTS: The findings showed that: (1) The individual level of psychological stress reaction was positively associated with bedtime procrastination; (2) Smartphone addiction mediated the effect of psychological stress reaction on bedtime procrastination; (3) Family cohesion moderated the relationship among psychological stress reaction, smartphone addiction and bedtime procrastination. CONCLUSIONS: This study revealed the effect of smartphone addiction on the relationship between psychological stress reaction and bedtime procrastination during the COVID-19 pandemic, and these findings could provide novel evidence that family cohesion may serve as a protective factor against the negative consequences of smartphone addiction on bad bedtime procrastination.


Subject(s)
COVID-19 , Procrastination , Humans , Young Adult , Internet Addiction Disorder , Pandemics , Stress, Psychological , Smartphone
4.
Eur J Neurosci ; 58(8): 3892-3902, 2023 10.
Article in English | MEDLINE | ID: mdl-37779210

ABSTRACT

The supraspinal mechanism plays a key role in developing and maintaining chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). However, it is not clear how white matter changes in young and middle-aged males with CP/CPPS. In this cross-sectional study, 23 CP/CPPS patients and 22 healthy controls (HCs) were recruited. Tract-based spatial statistics was applied to investigate the differences in diffusion tensor imaging metrics, including fractional anisotropy (FA), mean diffusion (MD), radial diffusion (RD) and axial diffusion (AD), between CP/CPPS patients and HCs. The study also examined the association between white matter alterations and clinical variables in patients using correlation analysis. Compared with HCs, patients showed decreased FA, MD, RD and AD in the body and genu of the corpus callosum and right anterior corona radiata. In addition, they showed increased FA along with decreased MD, RD and AD in the left posterior limb of the internal capsule (PLIC-L), left external capsule and left cerebral peduncle. The FA of PLIC-L was negatively correlated with disease duration (r = -.54, corrected p = .017), while MD and RD were positively correlated (r = .45, corrected p = .042; r = .57, corrected p = .017). These results suggest that CP/CPPS is associated with extensive changes in white matter tracts, which are involved in pain processing. In particular, the FA, MD and RD values in the PLIC-L were correlated with the disease duration, indicating that the long-term course of CP/CPPS may have effects on the white matter microstructure of the pain perception pathways.


Subject(s)
Prostatitis , White Matter , Male , Middle Aged , Humans , White Matter/diagnostic imaging , Brain/diagnostic imaging , Diffusion Tensor Imaging/methods , Cross-Sectional Studies , Prostatitis/diagnostic imaging , Pelvic Pain/diagnostic imaging
5.
J Cancer Res Clin Oncol ; 149(17): 15623-15640, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37656244

ABSTRACT

BACKGROUND: The advantages of radiotherapy for head and neck squamous cell carcinoma (HNSCC) depend on the radiation sensitivity of the patient. Here, we established and verified radiological factor-related gene signature and built a prognostic risk model to predict whether radiotherapy would be beneficial. METHODS: Data from The Cancer Genome Atlas, Gene Expression Omnibus, and RadAtlas databases were subjected to LASSO regression, univariate COX regression, and multivariate COX regression analyses to integrate genomic and clinical information from patients with HNSCC. HNSCC radiation-related prognostic genes were identified, and patients classified into high- and low-risk groups, based on risk scores. Variations in radiation sensitivity according to immunological microenvironment, functional pathways, and immunotherapy response were investigated. Finally, the expression of HNSCC radiation-related genes was verified by qRT-PCR. RESULTS: We built a clinical risk prediction model comprising a 15-gene signature and used it to divide patients into two groups based on their susceptibility to radiation: radiation-sensitive and radiation-resistant. Overall survival was significantly greater in the radiation-sensitive than the radiation-resistant group. Further, our model was an independent predictor of radiotherapy response, outperforming other clinical parameters, and could be combined with tumor mutational burden, to identify the target population with good predictive value for prognosis at 1, 2, and 3 years. Additionally, the radiation-resistant group was more vulnerable to low levels of immune infiltration, which are significantly associated with DNA damage repair, hypoxia, and cell cycle regulation. Tumor Immune Dysfunction and Exclusion scores also suggested that the resistant group would respond less favorably to immunotherapy. CONCLUSIONS: Our prognostic model based on a radiation-related gene signature has potential for application as a tool for risk stratification of radiation therapy for patients with HNSCC, helping to identify candidates for radiation therapy and overcome radiation resistance.


Subject(s)
DNA Repair , Head and Neck Neoplasms , Humans , Prognosis , Squamous Cell Carcinoma of Head and Neck/genetics , Squamous Cell Carcinoma of Head and Neck/radiotherapy , Databases, Factual , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/radiotherapy , Tumor Microenvironment
6.
Cancer Med ; 12(17): 17660-17670, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37563937

ABSTRACT

OBJECTIVES: The aim of this study was to compare the metastatic patterns of synchronous bone metastasis (SBM) and metachronous bone metastasis (MBM) in nasopharyngeal carcinoma (NPC). METHODS: This study included bone metastases in NPC patients from 2005 to 2016 in a Chinese hospital. Cohort 1 was collected from 2005 to 2010 for discovery, and Cohort 2 from 2011 to 2016 for validation. The chi-squared test, Wilcoxon rank sum test, and Kaplan-Meier technique were used to compare site, time, and survival between cohorts 1 and 2. Prognostic factors were analyzed using univariate or multivariate Cox regression. RESULTS: Cohort 1 had 112 individuals with SBM and 394 with MBM, and cohort 2 had 328 with SBM and 307 with MBM. The thoracic vertebra was the most frequently affected site of metastasis. Patients with SBM more often had metastasis to the cervical vertebrae compared with patients with MBM (34.5% vs. 22.3%, p < 0.05). Patients with SBM had better overall survival (42.2 months, 95% CI: 33.9-50.7) than patients with MBM (24.9 months, 95% CI: 22.2-28.7). Age at bone metastasis detection, metastasis to other organs, and more bone metastasis locations were associated with worse prognosis. The majority of MBMs occurred at 7 to 18 months after NPC diagnosis. CONCLUSION: Radiotherapy does not modify the metastatic patterns of NPC bone metastases. Patients with SBM tend to have metastasis to the cervical vertebra, which is close to the nasopharynx. Paying more attention to bone metastases during follow-up in the first 2 years after an NPC diagnosis.

7.
Lancet Digit Health ; 5(9): e560-e570, 2023 09.
Article in English | MEDLINE | ID: mdl-37625894

ABSTRACT

BACKGROUND: Mediastinal neoplasms are typical thoracic diseases with increasing incidence in the general global population and can lead to poor prognosis. In clinical practice, the mediastinum's complex anatomic structures and intertype confusion among different mediastinal neoplasm pathologies severely hinder accurate diagnosis. To solve these difficulties, we organised a multicentre national collaboration on the basis of privacy-secured federated learning and developed CAIMEN, an efficient chest CT-based artificial intelligence (AI) mediastinal neoplasm diagnosis system. METHODS: In this multicentre cohort study, 7825 mediastinal neoplasm cases and 796 normal controls were collected from 24 centres in China to develop CAIMEN. We further enhanced CAIMEN with several novel algorithms in a multiview, knowledge-transferred, multilevel decision-making pattern. CAIMEN was tested by internal (929 cases at 15 centres), external (1216 cases at five centres and a real-world cohort of 11 162 cases), and human-AI (60 positive cases from four centres and radiologists from 15 institutions) test sets to evaluate its detection, segmentation, and classification performance. FINDINGS: In the external test experiments, the area under the receiver operating characteristic curve for detecting mediastinal neoplasms of CAIMEN was 0·973 (95% CI 0·969-0·977). In the real-world cohort, CAIMEN detected 13 false-negative cases confirmed by radiologists. The dice score for segmenting mediastinal neoplasms of CAIMEN was 0·765 (0·738-0·792). The mediastinal neoplasm classification top-1 and top-3 accuracy of CAIMEN were 0·523 (0·497-0·554) and 0·799 (0·778-0·822), respectively. In the human-AI test experiments, CAIMEN outperformed clinicians with top-1 and top-3 accuracy of 0·500 (0·383-0·633) and 0·800 (0·700-0·900), respectively. Meanwhile, with assistance from the computer aided diagnosis software based on CAIMEN, the 46 clinicians improved their average top-1 accuracy by 19·1% (0·345-0·411) and top-3 accuracy by 13·0% (0·545-0·616). INTERPRETATION: For mediastinal neoplasms, CAIMEN can produce high diagnostic accuracy and assist the diagnosis of human experts, showing its potential for clinical practice. FUNDING: National Key R&D Program of China, National Natural Science Foundation of China, and Beijing Natural Science Foundation.


Subject(s)
Mediastinal Neoplasms , Humans , Mediastinal Neoplasms/diagnosis , Mediastinum , Artificial Intelligence , Cohort Studies , Diagnosis, Computer-Assisted
8.
Chronobiol Int ; 40(3): 234-245, 2023 03.
Article in English | MEDLINE | ID: mdl-36597182

ABSTRACT

Chronotype reflects individual differences in circadian rhythms and influences individual psychology and behavior. Previous studies found altered subcortical structures are closely related to individual chronotypes. However, these studies have been conducted mainly using voxel-based morphometry and traditional volume measurement methods with certain limitations. This study aimed to investigate subcortical aberrant volume and shape patterns in late chronotypes (LC) young adults compared to early chronotypes (EC) young adults. Magnetic resonance imaging (MRI) scanning and chronotype assessment were performed once for all participants, including 49 LC young adults and 49 matched EC young adults. The morningness and eveningness preferences were assessed using the Chronotype Questionnaire. A vertex-wise shape analysis was conducted to analyze structural MRI data. There were no significant differences in brain tissue volume and subcortical structural volume between groups. LC young adults showed significant regional shape atrophy in the left ventral posterior thalamus compared to EC individuals. A significant correlation was found between the regional shape atrophy of left ventral posterior thalamus and the score of Chronotype Questionnaire in LC young adults. Regional shape alteration of left thalamus was closely related to the chronotype, and LC may be a potential risk factor for sleep-related behavioral and mental problems in young adults. However, the predominantly female sample and the failure to investigate the effect of chronotype on the subcortical structure-function network are limitations of this study. Further prospective studies are needed to investigate the temporal characteristics of thalamic shape changes and consequent behavioral and psychiatric problems in adults with LC.


Subject(s)
Circadian Rhythm , Sleep Wake Disorders , Humans , Female , Young Adult , Male , Chronotype , Sleep , Thalamus/diagnostic imaging , Surveys and Questionnaires
9.
Light Sci Appl ; 12(1): 5, 2023 Jan 02.
Article in English | MEDLINE | ID: mdl-36588125

ABSTRACT

Being capable of sensing broadband infrared (IR) light is vitally important for wide-ranging applications from fundamental science to industrial purposes. Two-dimensional (2D) topological semimetals are being extensively explored for broadband IR detection due to their gapless electronic structure and the linear energy dispersion relation. However, the low charge separation efficiency, high noise level, and on-chip integration difficulty of these semimetals significantly hinder their further technological applications. Here, we demonstrate a facile thermal-assisted tellurization route for the van der Waals (vdW) growth of wafer-scale phase-controlled 2D MoTe2 layers. Importantly, the type-II Weyl semimetal 1T'-MoTe2 features a unique orthorhombic lattice structure with a broken inversion symmetry, which ensures efficient carrier transportation and thus reduces the carrier recombination. This characteristic is a key merit for the well-designed 1T'-MoTe2/Si vertical Schottky junction photodetector to achieve excellent performance with an ultrabroadband detection range of up to 10.6 µm and a large room temperature specific detectivity of over 108 Jones in the mid-infrared (MIR) range. Moreover, the large-area synthesis of 2D MoTe2 layers enables the demonstration of high-resolution uncooled MIR imaging capability by using an integrated device array. This work provides a new approach to assembling uncooled IR photodetectors based on 2D materials.

10.
J Psychiatr Res ; 158: 95-103, 2023 02.
Article in English | MEDLINE | ID: mdl-36580868

ABSTRACT

Cocaine use is a major public health problem with significant negative consequences at the individual and societal levels. Cocaine use disorder (CUD) is closely associated with brain structure alterations, which are mainly analyzed using voxel-based morphometric and traditional volumetric methods with certain limitations. This study conducted vertex-wise shape analysis to examine the effects of cocaine use on surface-based alterations of the basal ganglia in CUD. A total of 68 CUD individuals and 52 matched healthy controls (HCs) were enrolled in the study and underwent MRI scans and clinical measures. There were no significant differences in the volume of brain tissues and subcortical structures between groups. Related to HCs, CUD individuals showed regional surface atrophy of the left medial anterior thalamus, right medial posterior thalamus, and right dorsal anterior caudate, which were found to exhibit more significant surface atrophy in CUD individuals with onset age of cocaine use below 18. Furthermore, surface-based alteration of the right dorsal anterior caudate was significantly associated with years of cocaine use and the onset age of cocaine use in CUD individuals. Furthermore, both CUD individuals with onset age of cocaine use below 18 and CUD individuals with onset age of cocaine use above 18 showed similar significant relationship patterns between regional surface alteration of right dorsal anterior caudate and the onset age of cocaine use. These findings shed light on the effect of cocaine use on basal ganglia, help us understand the neural basis of cocaine dependence, and further provide effective interventions for CUD.


Subject(s)
Cocaine-Related Disorders , Cocaine , Humans , Basal Ganglia/diagnostic imaging , Brain , Cocaine-Related Disorders/diagnostic imaging , Magnetic Resonance Imaging/methods
11.
Acta Radiol ; 64(2): 572-580, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35369721

ABSTRACT

BACKGROUND: Quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) may have the potential to reflect angiogenesis and proliferation of pulmonary neoplasms. PURPOSE: To verify whether DCE-MRI can identify pulmonary neoplasm property and evaluate the correlation of DCE-MRI perfusion parameters with microvessel density (MVD) and Ki-67 in lung cancer. MATERIAL AND METHODS: This study enrolled 65 patients with one pulmonary neoplasm who underwent computed tomography-guided percutaneous lung biopsy with pathological diagnosis (43 malignant, 22 benign; mean age = 59.71 ± 11.72 years). All patients did DCE-MRI before biopsy. Quantitative MRI parameters including endothelial transfer constant (Ktrans), flux rate constant (Kep), and fractional extravascular extracellular space (EES) volume (Ve) were calculated by extended Tofts linear model. MVD was evaluated by CD34-expressing tumor vessels. Proliferation was assessed by Ki-67 staining. The correlations of parameters with MVD and Ki-67 expression were analyzed. RESULTS: Ktrans and Kep values were significantly increased in malignant lesions compared to benign lesions (P = 0.001 and 0.022, respectively), whereas no statistical difference in Ve was found. The CD34 expression was positively correlated to Ktrans (r = 0.608; P = 0.004) and Kep (r = 0.556; P = 0.001). Subsequent subtype analyses also showed positive correlations of Ktrans and Kep with MVD in adenocarcinoma group (r = 0.550 and 0.563; P = 0.012 and 0.015, respectively). No significant correlation was found between these parameters and Ki-67. CONCLUSION: Ktrans and Kep may distinguish benign and malignant pulmonary neoplasm. Ktrans and Kep, with their positive correlation to MVD, can be used as non-invasive parameters reflecting lung cancer angiogenesis.


Subject(s)
Lung Neoplasms , Magnetic Resonance Imaging , Humans , Middle Aged , Aged , Ki-67 Antigen/metabolism , Magnetic Resonance Imaging/methods , Biopsy , Lung Neoplasms/diagnostic imaging , Perfusion , Contrast Media
12.
Adv Mater ; 35(50): e2205807, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36036512

ABSTRACT

Ultrafine-grained (UFG) refractory metals are promising materials for applications in aerospace, microelectronics, nuclear energy, and many others under extreme environments. Powder metallurgy (PM) allows to produce such materials with well-controlled chemistry and microstructure at multiple length scales and near-net shape manufacturing. However, sintering refractory metals to full density while maintaining a fine microstructure is still challenging due to the high sintering temperature and the difficulty to separate the kinetics of densification versus grain growth. Here an overview of the sintering issues, microstructural design rules, and PM practices towards UFG and nanocrystalline refractory metals are sought to be provided. The previous efforts shall be reviewed to address the processing challenges, including the use of fine/nanopowders, second-phase grain growth inhibitors, and field-assisted sintering techniques. Recently, pressureless two-step sintering has been successfully demonstrated in producing dense UFG refractory metals down to ≈300 nm average grain size with a uniform microstructure and this technological breakthrough shall be reviewed. PM progresses in specific materials systems shall be next reviewed, including elementary metals (W and Mo), refractory alloys (W-Re), refractory high-entropy alloys, and their composites. Last, future developments and the endeavor towards UFG and nanocrystalline refractory metals with exceptionally uniform microstructure and improved properties are outlined.

13.
CNS Neurosci Ther ; 28(5): 714-723, 2022 05.
Article in English | MEDLINE | ID: mdl-35048524

ABSTRACT

AIMS: Chronic neck and shoulder pain (CNSP) is a common neurological disorder, which females are more likely to suffer from. The periaqueductal gray (PAG) plays a key role in the descending modulation of pain. This study aimed to investigate altered PAG-based functional connectivity (FC) in female patients with CNSP related to healthy controls (HCs) and the effect of acupuncture for female patients with CNSP using PAG-based FC biomarkers. METHODS: PAG-based FC value was calculated based on resting-state functional images and then compared between patients with CNSP at pre-acupuncture, post-acupuncture, and HCs. Then, correlational analyses were performed to examine the relationships between increased PAG-based FC strength and improved clinical parameters in patients after acupuncture treatment. RESULTS: Before acupuncture treatment, compared to HCs, patients with CSNP showed altered PAG-based FC with widely distributed brain regions, including the left medial superior frontal gyrus, bilateral posterior insula (pIns), and cingulate gyrus. After treatment, patients with CNSP exhibited specially improved PAG-pIns FC compared to that before treatment, and no significant difference was observed in the increased PAG-pIns FC strength between HCs and patients with CNSP after treatment. Furthermore, pain catastrophizing reduction was significantly correlated with the increased PAG-pIns FC strength in patients after treatment. CONCLUSION: The effect of acupuncture treatment may relate to the increased PAG-pIns FC, which significantly correlated with pain catastrophizing reduction after treatment. These findings shed important mechanistic information on the role of therapeutic approaches in treating chronic neck and shoulder pain.


Subject(s)
Acupuncture Therapy , Periaqueductal Gray , Brain Mapping , Female , Humans , Magnetic Resonance Imaging/methods , Periaqueductal Gray/diagnostic imaging , Shoulder Pain/diagnostic imaging , Shoulder Pain/therapy
14.
Nanoscale ; 13(31): 13550-13557, 2021 Aug 21.
Article in English | MEDLINE | ID: mdl-34477759

ABSTRACT

Broadband photodetection is of vital importance for both civil and technological applications. The widespread use of commercial photodiodes based on traditional semiconductors (e.g. GaN, Si, and InGaAs) is limited to the relatively narrow response range. In this work, we have demonstrated a self-driven and broadband photodetector based on WS2/pyramid Si 2D/3D mixed-dimensional van der Waals (vdW) heterojunction, which is assembled by directly transferring 2D WS2 film on 3D pyramid Si. Thanks to the enhanced light absorption with the pyramid Si structure, the defect-induced narrowed bandgap of the WS2 film, and high-quality vdW heterojunction, impressive device performances in terms of a large responsivity of 290 mA W-1, a high specific detectivity of up to 2.6 × 1014 Jones and an ultrabroad response spectrum ranging from 265 nm to 3.0 µm are achieved at zero bias. Importantly, the photodetector can function as an infrared imaging cell with a high spatial resolution. The totality of these excellent features confirms that the demonstrated WS2/pyramid Si 2D/3D mixed-dimensional vdW heterojunction device may hold great promise for applications in high-performance broadband infrared photodetection and imaging.

15.
Front Psychiatry ; 12: 699388, 2021.
Article in English | MEDLINE | ID: mdl-34421680

ABSTRACT

The unfamiliar and menacing epidemic has undoubtedly increased the anxiety of students. Therefore, the strategies to reduce anxiety are urgently required. The present study principally investigated a protective mechanism of future orientation in anxiety during the low-risk period of COVID-19 outbreak. The study was conducted in 528 non-infected students (range = 16-24 years) recruited from five universities in China. The participants completed questionnaires between January 22, 2021, and January 24, 2021. Chain intermediary analyses were performed after controlling for gender and age. Results indicated that future orientation lowers anxiety through (a) optimization in primary and secondary control, (b) resilience, and (c) chain mediating path of optimization in primary and secondary control coupled with resilience. We investigated how individuals deal with risk factors after encountering adversity and how their psychological flexibility stimulates and promotes them to achieve a well-adapted developmental state. This study provided reference suggestions on reducing anxiety levels during an emergency.

16.
Eur J Radiol ; 140: 109749, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34000599

ABSTRACT

PURPOSE: To develop a predictive model to determine risk factors of pneumothorax in patients undergoing the computed tomography (CT)1-guided coaxial core needle lung biopsy (CCNB). METHODS: A total of 489 patients who underwent CCNBs with an 18-gauge coaxial core needle were retrospectively included. Patient characteristics, primary pulmonary disease, target lesion image characteristics and biopsy-related variables were evaluated as potential risk factors of pneumothorax which was determined on the chest X-ray and CT scans. Univariate and multivariate logistic regressions were used to identify the independent risk factors of pneumothorax and establish the predictive model, which was presented in the form of a nomogram. The discrimination and calibration of the model were evaluated as well. RESULTS: The incidence of pneumothorax was 32.91 % and 31.42 % in the development and validation groups, respectively. Age, emphysema, pleural thickening, lesion location, lobulation sign, and size grade were identified independent risk factors of pneumothorax at the multivariate logistic regression model. The forming model produced an area under the curve of 0.718 (95 % CI = 0.660-0.776) and 0.722 (95 % CI = 0.638-0.805) in development and validation group, respectively. The calibration curve showed good agreement between predicted and actual probability. CONCLUSIONS: The predictive model for pneumothorax after CCNBs had good discrimination and calibration, which could help in clinical practice.


Subject(s)
Pneumothorax , Humans , Image-Guided Biopsy , Lung/diagnostic imaging , Nomograms , Pneumothorax/diagnostic imaging , Pneumothorax/etiology , Radiography, Interventional , Retrospective Studies , Risk Factors , Tomography, X-Ray Computed
17.
Acta Radiol ; 62(2): 198-205, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32460511

ABSTRACT

BACKGROUND: Computed tomography (CT)-guided percutaneous lung biopsy is usually performed by helical scanning. However, there are no studies on radiation dose, diagnostic accuracy, image quality, and complications based on axial scan mode. PURPOSE: To determine radiation dose, accuracy, image quality, and complication rate following an ultra-low-dose (ULD) protocol for CT-guided lung biopsy in clinic. MATERIAL AND METHODS: A total of 105 patients were enrolled to receive CT-guided lung biopsy. The use of an ULD protocol (axial scan) for CT-guided biopsy was initiated. Patients were randomly assigned to axial mode (Group A) and conventional helical mode (Group B) CT groups. 64-slice CT was performed for CT-guided pulmonary biopsy with an 18-G coaxial cutting biopsy needle. The radiation dose, accuracy, image quality, and complication rate were measured. RESULTS: Ninety-seven patients were selected for the final phase of the study. There was no significant difference between the two groups for pulmonary nodule characteristics (P > 0.05). The mean effective dose in group A (0.077 ± 0.010 mSv) was significantly reduced relative to group B (0.653 ± 0.177 mSv, P < 0.001). There was no significant difference in accuracy, image quality, and complication rate (P > 0.050) between the two modes. CONCLUSION: An ULD protocol for CT-guided lung nodule biopsy yields a reduction in the radiation dose without significant change in the accuracy, image quality, and complication rate relative to the conventional helical mode scan.


Subject(s)
Lung Neoplasms/diagnostic imaging , Radiation Dosage , Radiography, Interventional/methods , Solitary Pulmonary Nodule/diagnostic imaging , Tomography, X-Ray Computed/methods , Female , Humans , Image-Guided Biopsy , Lung/diagnostic imaging , Male , Middle Aged , Reproducibility of Results , Tomography, Spiral Computed/methods
18.
Nanoscale ; 12(35): 18031-18038, 2020 Sep 17.
Article in English | MEDLINE | ID: mdl-32869817

ABSTRACT

We report twisted 1T TaS2 bilayers synthesized by a lithiation exfoliation method. Atomic-scale observations reveal the existence of eight twist commensurate configurations from over 50 1T TaS2 bilayer samples in the twist angle range from 0° to 30° in which commensurate atomic configurations can be distinguished by scanning transmission electron microscopy. The limited number of twist angles, rather than random ones, indicates that there are energetically favorite twist angles in the naturally formed bilayers. Together with the interlayer distance measurements, the formation of the bilayer twist configurations is anticipated to be regulated by the stacking energy in the charge-density-wave system through interlayer van der Waals interactions. The findings of this work may pave a new way to fabricate twisted bilayer TMDs for exploring exotic properties from additional moiré periodicity.

19.
Br J Radiol ; 93(1108): 20190887, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31904268

ABSTRACT

OBJECTIVE: In spite of the well-known importance of thalamus in hemifacial spasm (HFS), the thalamic resting-state networks in HFS is still rarely mentioned. This study aimed to investigate resting-state functional connectivity (FC) of the thalamus in HFS patients and examine its association with clinical measures. METHODS: 25 HFS patients and 28 matched healthy controls underwent functional MRI at rest. Using the left and right thalamus as seed regions respectively, we compared the thalamic resting-state networks between patient and control groups using two independent sample t-test. RESULTS: Compared with controls, HFS patients exhibited strengthened bilateral thalamus-seeded FC with the parietal cortex. Enhanced FC between right thalamus and left somatosensory association cortex was linked to worse motor disturbance, and the increased right thalamus-right supramarginal gyrus connection were correlated with improvement of affective symptoms. CONCLUSION: Our findings indicate that the right thalamus-left somatosensory association cortex hyperconnectivity may represent the underlying neuroplasticity related to sensorimotor dysfunction. In addition, the upregulated FC between the right thalamus and right supramarginal gyrus in HFS, is part of the thalamo-default mode network pathway involved in emotional adaptation. ADVANCES IN KNOWLEDGE: This study provides new insights on the integrative role of thalamo-parietal connectivity, which participates in differential neural circuitry as a mechanism underlying motor and emotional functions in HFS patients.


Subject(s)
Hemifacial Spasm/physiopathology , Magnetic Resonance Imaging , Parietal Lobe/physiopathology , Rest , Thalamus/physiopathology , Case-Control Studies , Cross-Sectional Studies , Female , Hemifacial Spasm/diagnostic imaging , Hemifacial Spasm/psychology , Humans , Male , Middle Aged , Parietal Lobe/diagnostic imaging , Severity of Illness Index , Thalamus/diagnostic imaging
20.
Neuroradiology ; 62(3): 369-375, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31792569

ABSTRACT

PURPOSE: Refractory hemifacial contraction and comorbid emotional disorders are major annoyance suffered by patients with hemifacial spasm (HFS). It is currently unknown how whiter matter (WM) abnormalities in the brain contribute to HFS. METHODS: To investigate WM alterations in HFS, 26 patients and 29 matched healthy controls were ultimately recruited in this experiment. The whole brain diffusion tensor imaging (DTI) was acquired at 3.0 Tesla scanner. Tract-based spatial statistics (TBSS) analysis was applied to investigate the differences of DTI metrics (fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) axial diffusivity (AD)) between HFS patients and controls throughout brain WM. The relationship between the severity of facial spasm and affective disturbance in HFS patients, and WM abnormalities was examined using spearman correlation analyses. RESULTS: TBSS method showed structural alterations in the genu and body of corpus callosum; bilateral inferior longitudinal fasciculus (ILF) and inferior frontal-occipital fasciculus (IFOF); left superior longitudinal fasciculus, anterior, posterior, and superior portion of corona radiata; left posterior limb of the internal capsule; and left posterior thalamic radiation in HFS patients compared with healthy subjects. In addition, the overlapped region of decreased FA together with increased RD and MD was merely localized in the right ILF and IFOF in the HFS group, and abnormality of RD value in this region was positively correlated with the patients' spasm score. CONCLUSIONS: The present study indicate extensive disruptions of WM integrity, especially the RD changes in right ILF and IFOF, which may provide alternative imaging clues for evaluating the characteristics of HFS.


Subject(s)
Diffusion Tensor Imaging/methods , Hemifacial Spasm , White Matter/diagnostic imaging , Anisotropy , Case-Control Studies , Female , Humans , Male , Middle Aged , Neuropsychological Tests
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