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2.
Sensors (Basel) ; 24(10)2024 May 15.
Article in English | MEDLINE | ID: mdl-38793992

ABSTRACT

A number of image dehazing techniques depend on the estimation of atmospheric light intensity. The majority of dehazing algorithms do not incorporate a physical model to estimate atmospheric light, leading to reduced accuracy and significantly impacting the effectiveness of dehazing. This article presents a novel approach for estimating atmospheric light using the polarization state and polarization degree gradient of the sky. We utilize this approach to enhance the outcomes of image dehazing by applying it to pre-existing dehazing algorithms. Our study and development of a real-time dehazing system has shown that the approach we propose has a clear advantage over previous methods for estimating ambient light. After incorporating the proposed approach into existing defogging methods, a significant improvement in the effectiveness of defogging was noted through the assessment of various criteria such as contrast, PSNR, and SSIM.

3.
Nano Lett ; 24(15): 4336-4345, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38567915

ABSTRACT

This study demonstrates the conceptual design and fabrication of a vertically integrated monolithic (VIM) neuromorphic device. The device comprises an n-type SnO2 nanowire bottom channel connected by a shared gate to a p-type P3HT nanowire top channel. This architecture establishes two distinct neural pathways with different response behaviors. The device generates excitatory and inhibitory postsynaptic currents, mimicking the corelease mechanism of bilingual synapses. To enhance the signal processing efficiency, we employed a bipolar spike encoding strategy to convert fluctuating sensory signals to spike trains containing positive and negative pulses. Utilizing the neuromorphic platform for synaptic processing, physiological signals featuring bidirectional fluctuations, including electrocardiogram and breathing signals, can be classified with an accuracy of over 90%. The VIM device holds considerable promise as a solution for developing highly integrated neuromorphic hardware for healthcare and edge intelligence applications.


Subject(s)
Nanowires , Synapses
4.
Sci Rep ; 14(1): 2305, 2024 01 27.
Article in English | MEDLINE | ID: mdl-38280899

ABSTRACT

This transition from gathering to cultivation is a significant aspect of studying early agricultural practices. Fruit trees are an essential component of food resources and have played a vital role in both ancient and modern agricultural production systems. The jujube (Ziziphus jujuba Mill.), with its long history of cultivation in northern China, holds great importance in uncovering the diet of prehistoric humans and understanding the origins of Chinese agricultural civilization. This paper focuses on the domestication of jujube by analyzing the morphology of jujube stones found in three Neolithic sites in northern China's Qi River basin, Zhujia, Wangzhuang, and Dalaidian. The measurements of these jujube kernels are compared with those found in other areas of northern China, as well as modern jujube kernels that were collected. The measurements revealed that the length-to-diameter (L/D) ratio of sour jujube kernels ranged from 1.36 to 1.78, whereas the L/D ratio of cultivated jujube stones varied between 1.96 and 4.23. Furthermore, jujube stones obtained from Zhujia and Wangzhuang sites exhibit pointed ends and possess an elongated oval or narrow oval shape overall, which is indicative of clearly artificial domestication traits. Therefore, this study suggests that jujube was selected and cultivated as an important food supplement in the Qi River basin no later than around 6200 BP.


Subject(s)
Ziziphus , Humans , Qi , Rivers , Fruit , China
5.
Nat Commun ; 14(1): 7181, 2023 11 07.
Article in English | MEDLINE | ID: mdl-37935671

ABSTRACT

We demonstrate an artificially-intelligent cornea that can assume the functions of the native human cornea such as protection, tactile perception, and light refraction, and possesses sensory expansion and interactive functions. These functions are realized by an artificial corneal reflex arc that is constructed to implement mechanical and light information coding, information processing, and the regulation of transmitted light. Digitally-aligned, long and continuous zinc tin oxide (ZTO) semiconductor fabric patterns were fabricated as the active channels of the artificial synapse, which are non-toxic, heavy-metal-free, low-cost, and ensure superior comprehensive optical properties (transmittance >99.89%, haze <0.36%). Precisely-tuned crystal-phase structures of the ZTO fibers enabled reconfigurable synaptic plasticity, which is applicable to encrypted communication and associative learning. This work suggests new strategies for the tuning of synaptic plasticity and the design of visual neuroprosthetics, and has important implications for the development of neuromorphic electronics and for visual restoration.


Subject(s)
Touch Perception , Zinc Oxide , Humans , Touch , Electronics , Intelligence , Cornea
6.
Article in English | MEDLINE | ID: mdl-37683359

ABSTRACT

The leopard coral grouper (Plectropomus leopardus) is a coral reef fish species that exhibits rapid and diverse color variation. However, the presence of melanoma and the high proportion of individuals displaying black color in artificial breeding have led to reduced economic and ornamental value. To pinpoint single nucleotide polymorphisms (SNPs) and potential genes linked to the black pigmentation characteristic in this particular species, This study gathered a cohort of 360 specimens from diverse origins and conducted a comprehensive genome-wide association analysis (GWAS) employing whole-genome resequencing. As a result, 57 SNPs related to the black skin trait were identified, and a grand total of 158 genes were annotated within 50 kb of these SNPs. Subsequently, GWAS was applied to three populations (LED, QHH, and QHL), and the corresponding results were compared with the analysis results of the total population. The results of the four GWAS models showed significant enrichment in Rap1 signaling pathway, melanin biosynthesis, metabolic pathways, tyrosine metabolism, cAMP signaling pathway, AMPK signaling pathway, PI3K-Akt signaling pathway, EGFR tyrosine kinase inhibitor resistance, HIF-1 signaling pathway, Ras signaling pathway, MAPK signaling pathway, etc. (p < 0.05), which were mainly associated with eleven genes (POL4, MET, E2F2, COMT, ZBED1, TYRP2, FOXP2, THIKA, LORF2, MYH16 and SOX2). Significant differences (p < 0.05) were observed in the expression of all 11 genes in the dorsal skin tissue, in 10 genes except COMT in the ventral skin tissue, and in all 11 genes in the caudal fin tissue. These findings imply that the control of body color in the P. leopardus is the result of the joint action of multiple genes and signaling pathways. These findings will contribute to a more profound comprehension of the genetic attributes that underlie the development of black skin in the vibrant P. leopardus, thus furnishing a theoretical foundation for genetic enhancement.


Subject(s)
Anthozoa , Bass , Humans , Animals , Bass/genetics , Genome-Wide Association Study , Anthozoa/genetics , Phosphatidylinositol 3-Kinases/genetics , Kenya , Polymorphism, Single Nucleotide , Transcription Factors/genetics
7.
J Nucl Cardiol ; 30(6): 2427-2437, 2023 12.
Article in English | MEDLINE | ID: mdl-37221409

ABSTRACT

BACKGROUND: The aim of this research was to asses perfusion-defect detection-accuracy by human observers as a function of reduced-counts for 3D Gaussian post-reconstruction filtering vs deep learning (DL) denoising to determine if there was improved performance with DL. METHODS: SPECT projection data of 156 normally interpreted patients were used for these studies. Half were altered to include hybrid perfusion defects with defect presence and location known. Ordered-subset expectation-maximization (OSEM) reconstruction was employed with the optional correction of attenuation (AC) and scatter (SC) in addition to distance-dependent resolution (RC). Count levels varied from full-counts (100%) to 6.25% of full-counts. The denoising strategies were previously optimized for defect detection using total perfusion deficit (TPD). Four medical physicist (PhD) and six physician (MD) observers rated the slices using a graphical user interface. Observer ratings were analyzed using the LABMRMC multi-reader, multi-case receiver-operating-characteristic (ROC) software to calculate and compare statistically the area-under-the-ROC-curves (AUCs). RESULTS: For the same count-level no statistically significant increase in AUCs for DL over Gaussian denoising was determined when counts were reduced to either the 25% or 12.5% of full-counts. The average AUC for full-count OSEM with solely RC and Gaussian filtering was lower than for the strategies with AC and SC, except for a reduction to 6.25% of full-counts, thus verifying the utility of employing AC and SC with RC. CONCLUSION: We did not find any indication that at the dose levels investigated and with the DL network employed, that DL denoising was superior in AUC to optimized 3D post-reconstruction Gaussian filtering.


Subject(s)
Deep Learning , Myocardial Perfusion Imaging , Humans , Myocardial Perfusion Imaging/methods , Tomography, Emission-Computed, Single-Photon/methods , Heart , ROC Curve , Phantoms, Imaging , Image Processing, Computer-Assisted/methods
8.
Sensors (Basel) ; 23(7)2023 Apr 04.
Article in English | MEDLINE | ID: mdl-37050805

ABSTRACT

The wide-field telescope is a research hotspot in the field of aerospace. Increasing the field of view of the telescope can expand the observation range and enhance the observation ability. However, a wide field will cause some spatially variant optical aberrations, which makes it difficult to obtain stellar information accurately from astronomical images. Therefore, we propose a network for restoring wide-field astronomical images by correcting optical aberrations, called ASANet. Based on the encoder-decoder structure, ASANet improves the original feature extraction module, adds skip connection, and adds a self-attention module. With these methods, we enhanced the capability to focus on the image globally and retain the shallow features in the original image to the maximum extent. At the same time, we created a new dataset of astronomical aberration images as the input of ASANet. Finally, we carried out some experiments to prove that the structure of ASANet is meaningful from two aspects of the image restoration effect and quality evaluation index. According to the experimental results, compared with other deblur networks, the PSNR and SSIM of ASANet are improved by about 0.5 and 0.02 db, respectively.

9.
Sensors (Basel) ; 23(3)2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36772126

ABSTRACT

Ground-based telescopes are often affected by vignetting, stray light and detector nonuniformity when acquiring space images. This paper presents a space image nonuniform correction method using the conditional generative adversarial network (CGAN). Firstly, we create a dataset for training by introducing the physical vignetting model and by designing the simulation polynomial to realize the nonuniform background. Secondly, we develop a robust conditional generative adversarial network (CGAN) for learning the nonuniform background, in which we improve the network structure of the generator. The experimental results include a simulated dataset and authentic space images. The proposed method can effectively remove the nonuniform background of space images, achieve the Mean Square Error (MSE) of 4.56 in the simulation dataset, and improve the target's signal-to-noise ratio (SNR) by 43.87% in the real image correction.

10.
Phys Med ; 105: 102509, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36565556

ABSTRACT

Liver MRI images often suffer from degraded quality due to ghosting or blurring artifacts caused by patient respiratory or bulk motion. In this study, we developed a two-stage deep learning model to reduce motion artifact on dynamic contrast enhanced (DCE) liver MRIs. The stage-I network utilized a deep residual network with a densely connected multi-resolution block (DRN-DCMB) network to remove most motion artifacts. The stage-II network applied the generative adversarial network (GAN) and perceptual loss compensation to preserve image structural features. The stage-I network served as the generator of GAN and its pretrained parameters in stage-I were further updated via backpropagation during stage-II training. The stage-I network was trained using small image patches with simulated motion artifacts including image-space rotational and translational motion, and K-space based centric and interleaved linear motion, sinusoidal, and rotational motion to mimic liver motion patterns. The stage-II network training used full-size images with the same types of simulated motion. The liver DCE-MRI image volumes without obvious motion artifacts in 10 patients were used for the training process, of which 1020 images of 8 patients were used for training and 240 images of 2 patients for validation. Finally, the whole two-stage deep learning model was tested with simulated motion images (312 clean images from 5 test patients) and patient images with real motion artifacts (28 motion images from 12 patients). The resulted images after two-stage processing demonstrated reduced motion artifacts while preserved anatomic details without image blurriness, with SSIM of 0.935 ± 0.092, MSE of 60.7 ± 9.0 × 10-3, and PSNR of 32.054 ± 2.219.


Subject(s)
Artifacts , Liver , Humans , Liver/diagnostic imaging , Abdomen , Motion , Magnetic Resonance Imaging/methods , Image Processing, Computer-Assisted/methods
11.
J Nucl Cardiol ; 29(5): 2340-2349, 2022 Oct.
Article in English | MEDLINE | ID: mdl-34282538

ABSTRACT

BACKGROUND: We previously developed a deep-learning (DL) network for image denoising in SPECT-myocardial perfusion imaging (MPI). Here we investigate whether this DL network can be utilized for improving detection of perfusion defects in standard-dose clinical acquisitions. METHODS: To quantify perfusion-defect detection accuracy, we conducted a receiver-operating characteristic (ROC) analysis on reconstructed images with and without processing by the DL network using a set of clinical SPECT-MPI data from 190 subjects. For perfusion-defect detection hybrid studies were used as ground truth, which were created from clinically normal studies with simulated realistic lesions inserted. We considered ordered-subset expectation-maximization (OSEM) reconstruction with corrections for attenuation, resolution, and scatter and with 3D Gaussian post-filtering. Total perfusion deficit (TPD) scores, computed by Quantitative Perfusion SPECT (QPS) software, were used to evaluate the reconstructed images. RESULTS: Compared to reconstruction with optimal Gaussian post-filtering (sigma = 1.2 voxels), further DL denoising increased the area under the ROC curve (AUC) from 0.80 to 0.88 (P-value < 10-4). For reconstruction with less Gaussian post-filtering (sigma = 0.8 voxels), thus better spatial resolution, DL denoising increased the AUC value from 0.78 to 0.86 (P-value < 10-4) and achieved better spatial resolution in reconstruction. CONCLUSIONS: DL denoising can effectively improve the detection of abnormal defects in standard-dose SPECT-MPI images over conventional reconstruction.


Subject(s)
Deep Learning , Myocardial Perfusion Imaging , Humans , Image Processing, Computer-Assisted/methods , Myocardial Perfusion Imaging/methods , Perfusion , ROC Curve , Tomography, Emission-Computed, Single-Photon/methods
12.
Environ Sci Pollut Res Int ; 29(14): 20357-20369, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34735704

ABSTRACT

The Beiyun river flows through a hot spot region of Beijing-Tianjin-Hebei in China that serves a majority of occupants. However, the region experiences severe nitrate pollution, posing a threat to human health due to inadequate self-purification capacity. In that context, there is an urgent need to assess nitrate levels in this region. Herein, we used δ15N-NO3, δ18O-NO3 isotopes analysis, and stable isotope analysis model to evaluate the nitrate source apportionment in the Beiyun river. A meta-analysis was then used to compare the potential similarity of nitrate sources among the Beiyun riverine watershed and other watersheds. Results of nitrate source apportionment revealed that nitrate originated from the manure and sewage (contribution rate: 89.6%), soil nitrogen (5.9%), and nitrogen fertilizer (3.9%) in the wet season. While in the dry season, nitrate mainly originated from manure and sewage (91.6%). Furthermore, different land-use types exhibited distinct nitrate compositions. Nitrate in urban and suburban areas mostly was traced from manure and sewage (90.5% and 78.8%, respectively). Notably, the different nitrate contribution in the rural-urban fringe and plant-covered areas were manure and sewage (44.3% and 32.8%), soil nitrogen (26.9% and 35.7%), nitrogen fertilizer (23.5% and 29.4%), and atmospheric deposition (5.3% and 2.0%). Through a meta-analysis, we found nitrogen fertilizer, soil nitrogen, and manure and sewage as the main nitrate sources in the Beiyun riverine watershed or the other similar complexed watersheds in the temperate regions. Thus, this study provides a scientific basis for nitrate source apportionment and nitrate pollution preventive management in watersheds with complexed land-use types in temperate regions.


Subject(s)
Rivers , Water Pollutants, Chemical , China , Environmental Monitoring/methods , Humans , Nitrates/analysis , Nitrogen/analysis , Nitrogen Isotopes/analysis , Water Pollutants, Chemical/analysis
13.
Med Phys ; 48(1): 156-168, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33145782

ABSTRACT

PURPOSE: Post-reconstruction filtering is often applied for noise suppression due to limited data counts in myocardial perfusion imaging (MPI) with single-photon emission computed tomography (SPECT). We study a deep learning (DL) approach for denoising in conventional SPECT-MPI acquisitions, and investigate whether it can be more effective for improving the detectability of perfusion defects compared to traditional postfiltering. METHODS: Owing to the lack of ground truth in clinical studies, we adopt a noise-to-noise (N2N) training approach for denoising in SPECT-MPI images. We consider a coupled U-Net (CU-Net) structure which is designed to improve learning efficiency through feature map reuse. For network training we employ a bootstrap procedure to generate multiple noise realizations from list-mode clinical acquisitions. In the experiments we demonstrated the proposed approach on a set of 895 clinical studies, where the iterative OSEM algorithm with three-dimensional (3D) Gaussian postfiltering was used to reconstruct the images. We investigated the detection performance of perfusion defects in the reconstructed images using the non-prewhitening matched filter (NPWMF), evaluated the uniformity of left ventricular (LV) wall in terms of image intensity, and quantified the effect of smoothing on the spatial resolution of the reconstructed LV wall by using its full-width at half-maximum (FWHM). RESULTS: Compared to OSEM with Gaussian postfiltering, the DL denoised images with CU-Net significantly improved the detection performance of perfusion defects at all contrast levels (65%, 50%, 35%, and 20%). The signal-to-noise ratio (SNRD ) in the NPWMF output was increased on average by 8% over optimal Gaussian smoothing (P < 10-4 , paired t-test), while the inter-subject variability was greatly reduced. The CU-Net also outperformed a 3D nonlocal means (NLM) filter and a convolutional autoencoder (CAE) denoising network in terms of SNRD . In addition, the FWHM of the LV wall in the reconstructed images was varied by less than 1%. Furthermore, CU-Net also improved the detection performance when the images were processed with less post-reconstruction smoothing (a trade-off of increased noise for better LV resolution), with SNRD improved on average by 23%. CONCLUSIONS: The proposed DL with N2N training approach can yield additional noise suppression in SPECT-MPI images over conventional postfiltering. For perfusion defect detection, DL with CU-Net could outperform conventional 3D Gaussian filtering with optimal setting as well as NLM and CAE.


Subject(s)
Deep Learning , Image Processing, Computer-Assisted , Myocardial Perfusion Imaging , Algorithms , Humans , Phantoms, Imaging , Signal-To-Noise Ratio , Tomography, Emission-Computed, Single-Photon
14.
Med Phys ; 48(1): 264-272, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33159809

ABSTRACT

PURPOSE: The accurate segmentation of liver and liver tumors from CT images can assist radiologists in decision-making and treatment planning. The contours of liver and liver tumors are currently obtained by manual labeling, which is time-consuming and subjective. Computer-aided segmentation methods have been widely used in the segmentation of liver and liver tumors. However, due to the diversity of shape, volume, and image intensity, the segmentation is still a difficult task. In this study, we present a Spatial Feature Fusion Convolutional Network (SFF-Net) to automatically segment liver and liver tumors from CT images. METHODS: First, we extract side-outputs at each convolutional block in SFF-Net to make full use of multiscale features. Second, skip-connections are added in the down-sampling phase, therefore, the spatial information can be efficiently transferred to later layers. Third, we present feature fusion blocks (FFBs) to merge spatial features and high-level semantic features from early layers and later layers, respectively. Finally, a fully connected 3D conditional random fields (CRFs) is applied to refine the liver and liver tumor segmentation results. RESULTS: We test our method on the MICCAI 2017 Liver Tumor Segmentation (LiTS) challenge dataset. The Dice Global (DG) score, Dice per case (DC) score, Volume Overlap Error (VOE), Average Symmetric Surface Distance (ASSD), and tumor precision score are calculated to evaluate the liver and liver tumor segmentation accuracies. For the liver segmentation, DG is 0.955; DC is 0.937; VOE is 0.106; and ASSD is 3.678. For the tumor segmentation, DG is 0.746; DC is 0.592; VOE is 0.416; ASSD is 1.585 and the tumor precision score is 0.369. CONCLUSIONS: The SFF-Net learns more spatial information by adding skip-connections and feature fusion blocks. The experiments validate that our method can accurately segment liver and liver tumors from CT images.


Subject(s)
Liver Neoplasms , Neural Networks, Computer , Humans , Image Processing, Computer-Assisted , Liver Neoplasms/diagnostic imaging , Tomography, X-Ray Computed
15.
AMB Express ; 10(1): 195, 2020 Oct 30.
Article in English | MEDLINE | ID: mdl-33125582

ABSTRACT

Streptococcus suis serotype 2 (SS2) is a serious zoonotic pathogen; it can lead to symptoms of streptococcal toxic shock syndrome (STSS) in humans and sepsis in pigs, and poses a great threat to public health. The SS2 MetQ gene deletion strain has attenuated antiphagocytosis, although the mechanism of antiphagocytosis and pathogenesis of MetQ in SS2 has remained unclear. In this study, stable isotope labeling by amino acids in cell culture (SILAC) based liquid chromatography-mass spectrometry (LC-MS) and subsequent bioinformatics analysis was used to determine differentially expressed proteins of RAW264.7 cells infected with △MetQ and ZY05719. Proteomic results were verified by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting for selected proteins. Further research was focused mainly on immune system processes related to downregulated proteins, such as Src and Ccl9, and actin cytoskeleton and endocytosis related upregulated proteins, like Pstpip1 and Ppp1r9b. The proteomic results in this study shed light on the mechanism of antiphagocytosis and innate immunity of macrophages infected with △MetQ and ZY05719, which might provide novel targets to prevent or control the infection of SS2.

16.
Sci Rep ; 10(1): 14235, 2020 08 28.
Article in English | MEDLINE | ID: mdl-32859982

ABSTRACT

The oasis villages of the Tarim Basin served as hubs along the ancient Silk Road, and they played an important role in facilitating communication between the imperial centers of Asia. These villages were supported by an irrigated form of cereal farming that was specifically adapted to these early oasis settlements. In this manuscript, we present the results from new archaeobotanical analyses, radiocarbon dating, and organic carbon isotopic studies directly from carbonized seeds at the Wupaer site (1500-400 BC) in the Kashgar Oasis of the western Tarim Basin. Our results showed that early farming in the oasis relied on a mixed wheat and barley system, but after 1200 BC was intensified through more elaborate irrigation, the introduction of more water-demanding legumes, and possibly a greater reliance on free-threshing wheat. These crops and the knowledge of irrigated farming likely dispersed into the Tarim Basin through the mountains from southern Central Asia. Improved agricultural productivity in the Tarim Basin may also have led to demographic and socio-political shifts and fed into the increased exchange that is colloquially referred to as the Silk Road.

17.
Ecol Evol ; 10(11): 4828-4837, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32551064

ABSTRACT

Climate change poses a serious threat to biodiversity. Predicting the effects of climate change on the distribution of a species' habitat can help humans address the potential threats which may change the scope and distribution of species. Pterocarya stenoptera is a common fast-growing tree species often used in the ecological restoration of riverbanks and alpine forests in central and eastern China. Until now, the characteristics of the distribution of this species' habitat are poorly known as are the environmental factors that influence its preferred habitat. In the present study, the Maximum Entropy Modeling (Maxent) algorithm and the Genetic Algorithm for Ruleset Production (GARP) were used to establish the models for the potential distribution of this species by selecting 236 sites with known occurrences and 14 environmental variables. The results indicate that both models have good predictive power. Minimum temperature of coldest month (Bio6), mean temperature of warmest quarter (Bio10), annual precipitation (Bio12), and precipitation of driest month (Bio14) were important environmental variables influencing the prediction of the Maxent model. According to the models, the temperate and subtropical regions of eastern China had high environmental suitability for this species, where the species had been recorded. Under each climate change scenario, climatic suitability of the existing range of this species increased, and its climatic niche expanded geographically to the north and higher elevation. GARP predicted a more conservative expansion. The projected spatial and temporal patterns of P. stenoptera can provide reference for the development of forest management and protection strategies.

18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(3): 365-372, 2020 Jun 25.
Article in Chinese | MEDLINE | ID: mdl-32597076

ABSTRACT

The outbreak of pneumonia caused by novel coronavirus (COVID-19) at the end of 2019 was a major public health emergency in human history. In a short period of time, Chinese medical workers have experienced the gradual understanding, evidence accumulation and clinical practice of the unknown virus. So far, National Health Commission of the People's Republic of China has issued seven trial versions of the "Guidelines for the Diagnosis and Treatment of COVID-19". However, it is difficult for clinicians and laymen to quickly and accurately distinguish the similarities and differences among the different versions and locate the key points of the new version. This paper reports a computer-aided intelligent analysis method based on machine learning, which can automatically analyze the similarities and differences of different treatment plans, present the focus of the new version to doctors, reduce the difficulty in interpreting the "diagnosis and treatment plan" for the professional, and help the general public better understand the professional knowledge of medicine. Experimental results show that this method can achieve the topic prediction and matching of the new version of the program text through unsupervised learning of the previous versions of the program topic with an accuracy of 100%. It enables the computer interpretation of "diagnosis and treatment plan" automatically and intelligently.


Subject(s)
Coronavirus Infections/diagnosis , Coronavirus Infections/therapy , Machine Learning , Pneumonia, Viral/diagnosis , Pneumonia, Viral/therapy , Practice Guidelines as Topic , Betacoronavirus , COVID-19 , China , Humans , Pandemics , SARS-CoV-2
19.
Magn Reson Imaging ; 71: 69-79, 2020 09.
Article in English | MEDLINE | ID: mdl-32428549

ABSTRACT

OBJECTIVE: Magnetic resonance imaging (MRI) acquisition is inherently sensitive to motion, and motion artifact reduction is essential for improving image quality in MRI. METHODS: We developed a deep residual network with densely connected multi-resolution blocks (DRN-DCMB) model to reduce the motion artifacts in T1 weighted (T1W) spin echo images acquired on different imaging planes before and after contrast injection. The DRN-DCMB network consisted of multiple multi-resolution blocks connected with dense connections in a feedforward manner. A single residual unit was used to connect the input and output of the entire network with one shortcut connection to predict a residual image (i.e. artifact image). The model was trained with five motion-free T1W image stacks (pre-contrast axial and sagittal, and post-contrast axial, coronal, and sagittal images) with simulated motion artifacts. RESULTS: In other 86 testing image stacks with simulated artifacts, our DRN-DCMB model outperformed other state-of-the-art deep learning models with significantly higher structural similarity index (SSIM) and improvement in signal-to-noise ratio (ISNR). The DRN-DCMB model was also applied to 121 testing image stacks appeared with various degrees of real motion artifacts. The acquired images and processed images by the DRN-DCMB model were randomly mixed, and image quality was blindly evaluated by a neuroradiologist. The DRN-DCMB model significantly improved the overall image quality, reduced the severity of the motion artifacts, and improved the image sharpness, while kept the image contrast. CONCLUSION: Our DRN-DCMB model provided an effective method for reducing motion artifacts and improving the overall clinical image quality of brain MRI.


Subject(s)
Artifacts , Brain/diagnostic imaging , Deep Learning , Image Enhancement/methods , Magnetic Resonance Imaging , Movement , Signal-To-Noise Ratio , Contrast Media , Humans
20.
Vet Microbiol ; 243: 108653, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32273000

ABSTRACT

Porcine circovirus type 2 (PCV-2) and Streptococcus suis (S. suis) are common pathogens in pigs. Both pathogens are associated with the porcine respiratory disease complex. Clinically, coinfection of PCV-2 and S. suis are often detected in pigs with respiratory symptoms, while interactions between the two pathogens during coinfection and the coinfection pathogenesis are poorly understood. In this study, a piglet model coinfected with PCV-2 and Streptococcus suis serotype 2 (SS2) was established; coinfection of piglets increased the contents of SS2 in blood, and piglets showed more severe pneumonia, myocarditis and arthritis. Peripheral blood mononuclear cells (PBMCs) were collected and coinfected piglets showed high expression levels of inflammatory cytokines and TLR2, TLR4, while levels of CD4, CD8 and MHC II were reduced. In addition, in order to further explore the mechanisms of coinfection induced cytokine overexpression, an in vitro model of coinfection with PCV-2 and SS2 was established using cells of the porcine monocytic line 3D4/21. Similar to the in vivo results,coinfected cells exhibited increased expression of the cytokines IL-6, IL-8, TNF-α and the receptors TLR2, TLR4, while they showed a lower expression of MHC II than cells infected with SS2 alone. Furthermore, in coinfected 3D4/21 cells, both MAPK and NF-κB signaling pathways were activated, and the increased expression of IL-8 was related to TLR4. In general, coinfection with PCV-2 and SS2 exacerbated the inflammatory response and probably impaired macrophage antigen presentation, resulting in immune dysregulation and increasing the severity of host infection.


Subject(s)
Circoviridae Infections/veterinary , Circovirus/pathogenicity , Coinfection/veterinary , Streptococcal Infections/veterinary , Streptococcus suis/pathogenicity , Animals , Circoviridae Infections/immunology , Circovirus/immunology , Coinfection/immunology , Cytokines/genetics , Cytokines/immunology , Serogroup , Streptococcal Infections/immunology , Streptococcus suis/immunology , Swine , Swine Diseases/immunology , Swine Diseases/microbiology , Swine Diseases/virology , Virulence
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