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Contrastive mechanisms of lacustrine groundwater discharge and associated pollutant fluxes into two typical inland lakes in Inner Mongoli1,Northwest China
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作者 Yuanzhen Zhao Xiaohui Ren +5 位作者 Shen Qu Fu Liao Keyi Zhang Muhan Li Juliang Wang Ruihong Yu 《Journal of Environmental Sciences》 2026年第1期661-669,共9页
Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have n... Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have not been thoroughly investigated.In this study,multiple tracers(hydrochemistry,𝛿D,𝛿18O and 222Rn)were used to compare mechanisms of LGD in Daihai and Ulansuhai Lake in Inner Mongoli1,Northwest China.The hydrochemical types showed a trend from groundwater to lake water,indicating a hydraulic connection between them.In addition,the𝛿D and𝛿18O values of sediment pore water were between the groundwater and lake water,indicating the LGD processes.The radon mass balance model was used to estimate the average groundwater discharge rates of Daihai and Ulansuhai Lake,which were 2.79 mm/day and 3.02 mm/day,respectively.The total nitrogen(TN),total phosphorus(TP),and fluoride inputs associated with LGD in Daihai Lake accounted for 97.52%,96.59%,and 95.84%of the total inputs,respectively.In contrast,TN,TP and fluoride inputs in Ulansuhai Lake were 53.56%,40.98%,and 36.25%,respectively.This indicates that the pollutant inputs associated with LGD posed a potential threat to the ecological stability of Daihai and Ulansuhai Lake.By comparison,the differences of LGD process and associated pollutant flux were controlled by hydrogeological conditions,lakebed permeability and human activities.This study provides a reference for water resources management in Daihai and Ulansuhai Lake basins while improving the understanding of LGD in the Yellow River basin. 展开更多
关键词 Lacustrine groundwater discharge 222Rn mass balance model Pollutant fluxes contrastive mechanisms Daihai and Ulansuhai Lake
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Prolonged retention of oil-based iodinated contrast medium observed on plain abdominal radiograph after cesarean section:A case report
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作者 Akari Morita Toshiyuki Kakinuma +4 位作者 Arimi Segawa Satoshi Harada Seido Takae Midori Tamura Nao Suzuki 《World Journal of Clinical Cases》 2025年第29期144-149,共6页
BACKGROUND Oil-based iodinated contrast media have excellent contrast properties and are widely used for hysterosalpingographic evaluation of female infertility.On abdominal radiography and computed tomography(CT)scan... BACKGROUND Oil-based iodinated contrast media have excellent contrast properties and are widely used for hysterosalpingographic evaluation of female infertility.On abdominal radiography and computed tomography(CT)scans,their radiodensity is similar to that of metallic objects,which can sometimes lead to diagnostic confusion in the postoperative settings.In this case,retained oil-based contrast medium was observed on an abdominal radiograph following a cesarean section,making it difficult to differentiate from an intraperitoneal foreign body from surgery.The patient was a 37-year-old pregnant woman who was referred to our hospital at 32 weeks and 1 day of pregnancy due to complete placenta previa for mana-gement of pregnancy and delivery.An elective cesarean section was performed at 37 weeks and 3 days.A plain abdominal radiograph taken immediately after surgery revealed a near-round,hyperdense,mass-like shadow with a regular margin in the pelvic cavity.An intraperitoneal foreign body was suspected;therefore,an abdominal CT scan was performed.The foreign body was located on the left side of the pouch of Douglas and had a CT value of 7000 Hounsfield units,similar to that of metals.The CT value strongly suggested the presence of an artificial object.However,further inquiries with the patient and her previous physician revealed a history of hysterosalpingography.Accordingly,retained oil-based iodinated contrast medium was suspected,and observation of the object’s course was adopted.CONCLUSION When intraperitoneal foreign bodies are suspected on postoperative radiographs,the possibility of oil-based iodinated contrast medium retention should be considered. 展开更多
关键词 Oil-based contrast medium Cesarean section Retained surgical instruments contrast medium retention HYSTEROSALPINGOGRAPHY Female infertility Case report
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Accuracy of dual-contrast gastrointestinal ultrasonography in predicting lymph node metastasis in older adults with gastric cancer
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作者 Yue Jiang Shao-Hua Xu +3 位作者 Li Han Na Lu Shuai Huang Lei Wang 《World Journal of Gastrointestinal Oncology》 2025年第5期173-179,共7页
BACKGROUND Gastrointestinal dual-contrast ultrasonography(DCUS)is characterized by its high resolution,sensitivity,and specificity.AIM To determine the accuracy of DCUS in predicting lymph node metastasis in middle-ag... BACKGROUND Gastrointestinal dual-contrast ultrasonography(DCUS)is characterized by its high resolution,sensitivity,and specificity.AIM To determine the accuracy of DCUS in predicting lymph node metastasis in middle-aged and elderly patients with gastric cancer(GC).METHODS A total of 100 middle-aged and elderly patients with GC admitted to the Fourth Affiliated Hospital of Soochow University(Dushu Lake Hospital,Suzhou,China)between April 2022 and April 2024 were selected.The baseline data and lymph node metastasis status were collected.DCUS combined with intravenous contrast technology was used to calculate the enhancement time(ET),time to peak(TTP),and slope of the ascending branch wash-in rate(WIR).These indicators were used in assessing lymph node metastasis in patients with GC.RESULTS Among 100 middle-aged and elderly patients with GC,35(35.00%)had lymph node metastases.GC patients with lymph node metastasis had a higher propor-tion of stage II TNM classification and higher WIR values than those without lymph node metastasis.The ET and TTP values were lower in patients with lymph node metastases,and all differences were statistically significant(P<0.05).The area under the curve values for ET,TTP,WIR,and combined diagnosis of GC lymph node metastasis using DCUS were all>0.7.Optimal assessment was achieved when the cutoff values for ET,TTP,and WIR were set at 16.32 seconds,10.67 seconds,and 7.02,res-pectively.CONCLUSION DCUS-mediated assessment of ET,TTP,and WIR can effectively predict and evaluate lymph node metastasis status in patients with GC,with higher sensitivity when used in combination. 展开更多
关键词 Gastrointestinal contrast ultrasound Intravenous contrast Middle-aged and elderly Gastric cancer Lymph node metastasis Prediction
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Right-to-left shunt detection in patent foramen ovale:The value of synchronized contrast transcranial Doppler and contrast transthoracic echocardiography
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作者 Yu-Yin Wang Lu Xie +2 位作者 Jun-Bang Feng Yang-Yang Xu Chuan-Ming Li 《World Journal of Radiology》 2025年第5期84-86,共3页
Patent foramen ovale(PFO)is a common congenital heart disorder associated with stroke,decompression sickness and migraine.Combining synchronized contrast transcranial Doppler with contrast transthoracic echocardiograp... Patent foramen ovale(PFO)is a common congenital heart disorder associated with stroke,decompression sickness and migraine.Combining synchronized contrast transcranial Doppler with contrast transthoracic echocardiography has important clinical significance and can improve the accuracy of detecting right-left shunts(RLSs)in patients with PFO.In this letter,regarding an original study presented by Yao et al,we present our insights and discuss how to better help clinicians evaluate changes in PFO-related RLS. 展开更多
关键词 contrast transcranial Doppler contrast transthoracic echocardiography Combined multimodal ultrasound Patent foramen ovale Right-to-left shunt
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An improved neighbourhood-based contrast limited adaptive histogram equalization method for contrast enhancement on retinal images
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作者 Arjuna Arulraj Jeya Sutha Mariadhason Reena Rose Ronjalis 《International Journal of Ophthalmology(English edition)》 2025年第12期2225-2236,共12页
AIM:To find the effective contrast enhancement method on retinal images for effective segmentation of retinal features.METHODS:A novel image preprocessing method that used neighbourhood-based improved contrast limited... AIM:To find the effective contrast enhancement method on retinal images for effective segmentation of retinal features.METHODS:A novel image preprocessing method that used neighbourhood-based improved contrast limited adaptive histogram equalization(NICLAHE)to improve retinal image contrast was suggested to aid in the accurate identification of retinal disorders and improve the visibility of fine retinal structures.Additionally,a minimal-order filter was applied to effectively denoise the images without compromising important retinal structures.The novel NICLAHE algorithm was inspired by the classical CLAHE algorithm,but enhanced it by selecting the clip limits and tile sized in a dynamical manner relative to the pixel values in an image as opposed to using fixed values.It was evaluated on the Drive and high-resolution fundus(HRF)datasets on conventional quality measures.RESULTS:The new proposed preprocessing technique was applied to two retinal image databases,Drive and HRF,with four quality metrics being,root mean square error(RMSE),peak signal to noise ratio(PSNR),root mean square contrast(RMSC),and overall contrast.The technique performed superiorly on both the data sets as compared to the traditional enhancement methods.In order to assess the compatibility of the method with automated diagnosis,a deep learning framework named ResNet was applied in the segmentation of retinal blood vessels.Sensitivity,specificity,precision and accuracy were used to analyse the performance.NICLAHE–enhanced images outperformed the traditional techniques on both the datasets with improved accuracy.CONCLUSION:NICLAHE provides better results than traditional methods with less error and improved contrastrelated values.These enhanced images are subsequently measured by sensitivity,specificity,precision,and accuracy,which yield a better result in both datasets. 展开更多
关键词 contrast limited adaptive histogram equalization retinal imaging image preprocessing contrast enhancement
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Contrast-induced delayed coronary vasospasm and optical coherence tomography-confirmed plaque rupture-induced ST-segment elevation myocardial infarction:a case series of Kounis syndrome
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作者 Yuan XU Yu-Peng WANG +2 位作者 Yuan-Yuan FAN Wei FU Ling-Yun ZU 《Journal of Geriatric Cardiology》 2025年第8期746-750,共5页
Kounis syndrome(KS)is a rare but clinically significant condition characterized by the simultaneous occurrence of acute coronary syndrome(ACS)and allergic reactions,which can develop in patients with either normal or ... Kounis syndrome(KS)is a rare but clinically significant condition characterized by the simultaneous occurrence of acute coronary syndrome(ACS)and allergic reactions,which can develop in patients with either normal or diseased coronary arteries.[1,2]The condition is typically triggered by various allergens including medications(particularly contrast media),environmental factors,or food exposures,with symptom onset usually occurring within one hour of exposure. 展开更多
关键词 coronary arteries contrast media environmental allergic reactionswhich optical coherence tomography confirmed plaque rupture st segment elevation myocardial infarction contrast induced delayed coronary vasospasm kounis syndrome acute coronary syndrome acs
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Ultrasmall Superparamagnetic Iron Oxide Nanoparticles as Positive Contrast Agents in Low‐Field Magnetic Resonance Imaging
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作者 Ogechukwu Ngwu‐Hyacinth Aaron Alford +7 位作者 Caleb SRowe Ryan Willoughby S.Abdollah Mirbozorgi Steven ARothenberg Jesse Jones Abin Sajan Venkatesh P.Krishnasamy Mark Bolding 《iRADIOLOGY》 2025年第5期372-387,共16页
Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs ... Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs that primarily function as T2/T2*negative contrast agents,usSPIONs with core diameters below 5 nm can effectively shorten T1 relaxation times,producing bright signals in T1‐weighted images.This distinct behavior stems from their unique magnetic properties,including single‐domain configurations,surface spin canting,and rapid Néel relaxation dynamics,which are particularly enhanced at low magnetic field strengths.The biocompatibility of iron oxide,efficient renal clearance pathways,and versatility for surface functionalization offer potential advantages over gadolinium‐based agents,especially regarding safety concerns related to nephrogenic systemic fibrosis and gadolinium deposition.These nanoparticles show particular promise for applications in lowfield MRI,vascular imaging,targeted molecular imaging,and theranostic platforms.Although challenges remain in optimizing synthesis methods for consistent production of monodisperse usSPIONs with tailored surface chemistry,ongoing research continues to advance their potential for clinical translation.This review explores the mechanisms,synthesis approaches,applications,and future perspectives of usSPIONs as positive contrast agents in MRI. 展开更多
关键词 iron oxide nanoparticle low‐field MRI magnetic resonance imaging magnetite and maghemite positive contrast agent superparamagnetic iron oxide nanoparticle T1 MRI contrast agent T1 relaxivity ultrasmall superparamagnetic iron oxide nanoparticle
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Adult juvenile polyp bleeding detected by extravascular contrast leakage and treated with endoscopic clipping:A case report
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作者 Fumiya Kataoka Takayuki Nakanishi +7 位作者 Hiroshi Araki Shoichi Ichino Makoto Kamei Hiroyuki Makino Ryotaro Nagao Takayuki Asano Atsushi Tagami Hisataka Moriwaki 《World Journal of Gastrointestinal Endoscopy》 2025年第2期65-71,共7页
BACKGROUND Juvenile polyps(JPs)are non-neoplastic polyps.In adults,JPs present with hematochezia in only approximately half the patients and are often found incidentally during endoscopic screening.JPs have no mucosal... BACKGROUND Juvenile polyps(JPs)are non-neoplastic polyps.In adults,JPs present with hematochezia in only approximately half the patients and are often found incidentally during endoscopic screening.JPs have no mucosal fascia at the tip,and spontaneous shedding and massive gastrointestinal hemorrhage may occur.Thus,the JP bleeding detected in this case by extravascular contrast leakage on computed tomography scans and treated with endoscopic clipping is rare.CASE SUMMARY A previously healthy 31-year-old male patient presented with a 2-day history of bloody stools.Upon hospital arrival,rectal examination revealed fresh blood,and abdominal computed tomography scans showed extravascular contrast leakage from the lower rectum’s left-side wall.His blood pressure was slightly low at 104/62 mmHg.However,his pulse rate(69 bpm)and oxygen level(99%on room air)were within normal limits.Emergency endoscopy revealed a pedunculated lesion in the rectum covered by a non-neoplastic mucosal epithelium.No neoplastic lesions were observed at the tip of the polyp;however,pulsatile bleeding was detected at the distal end.We performed endoscopic hemostasis by clipping the stem and then performed a polypectomy above the stem to examine the lesion tissue.Histopathological evaluation revealed a cystically dilated gland without neoplastic lesions.A subsequent total colonoscopy revealed two JPs with characteristic edematous,smooth,and reddish surfaces close to the hemorrhagic lesion.Subsequent histopathological evaluation indicated findings characteristic of JP,such as severe inflammatory cell infiltration of the stroma and cystic dilatation of the glandular ducts.CONCLUSION There are no reports of adult JPs presenting with contrast extravasation where endoscopic hemostasis was successful,as in this case. 展开更多
关键词 contrast-enhanced computed tomography Endoscopic clipping Juvenile polyp Rectal bleeding contrast extravasation Case report
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Computed tomography pulmonary angiography using a 20% reduction in contrast medium dose delivered in a multiphasic injection 被引量:3
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作者 Mitchell Chen Gaith Mattar Jamal A Abdulkarim 《World Journal of Radiology》 CAS 2017年第3期143-147,共5页
AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmona... AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmonary embolism underwent spiral CTPA, out of whom fifty-seven received 75 mL and the remaining seventy a lower dose of 60 mL of contrast agent. Both doses were administered in a multiphasic injection. A minimum opacification threshold of 250 Hounsfield units(HU) in the main pulmonary artery is used for assessing the technical adequacy of the scans. RESULTS Mean opacification was found to be positively correlated to patient age(Pearson's correlation 0.4255, P < 0.0001) and independent of gender(male:female, 425.6 vs 450.4,P = 0.34). When age is accounted for, the study and control groups did not differ significantly in their mean opacification in the main(436.8 vs 437.9, P = 0.48),left(416.6 vs 419.8, P = 0.45) or the right pulmonary arteries(417.3 vs 423.5, P = 0.40). The number of sub-optimally opacified scans(the mean opacification in the main pulmonary artery < 250 HU) did not differ significantly between the study and control groups(7 vs 10).CONCLUSION A lower dose of iodine contrast at 60 mL can be feasibly used in CTPA without resulting in a higher number of sub-optimally opacified scans. 展开更多
关键词 Computed tomography pulmonary angiography contrast dose contrast induced nephropathy Acute kidney disease contrast safety contrast dose reduction Multiphasic injection
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A multimodal contrastive learning framework for predicting P-glycoprotein substrates and inhibitors 被引量:1
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作者 Yixue Zhang Jialu Wu +1 位作者 Yu Kang Tingjun Hou 《Journal of Pharmaceutical Analysis》 2025年第8期1810-1824,共15页
P-glycoprotein(P-gp)is a transmembrane protein widely involved in the absorption,distribution,metabolism,excretion,and toxicity(ADMET)of drugs within the human body.Accurate prediction of Pgp inhibitors and substrates... P-glycoprotein(P-gp)is a transmembrane protein widely involved in the absorption,distribution,metabolism,excretion,and toxicity(ADMET)of drugs within the human body.Accurate prediction of Pgp inhibitors and substrates is crucial for drug discovery and toxicological assessment.However,existing models rely on limited molecular information,leading to suboptimal model performance for predicting P-gp inhibitors and substrates.To overcome this challenge,we compiled an extensive dataset from public databases and literature,consisting of 5,943 P-gp inhibitors and 4,018 substrates,notable for their high quantity,quality,and structural uniqueness.In addition,we curated two external test sets to validate the model's generalization capability.Subsequently,we developed a multimodal graph contrastive learning(GCL)model for the prediction of P-gp inhibitors and substrates(MC-PGP).This framework integrates three types of features from Simplified Molecular Input Line Entry System(SMILES)sequences,molecular fingerprints,and molecular graphs using an attention-based fusion strategy to generate a unified molecular representation.Furthermore,we employed a GCL approach to enhance structural representations by aligning local and global structures.Extensive experimental results highlight the superior performance of MC-PGP,which achieves improvements in the area under the curve of receiver operating characteristic(AUC-ROC)of 9.82%and 10.62%on the external P-gp inhibitor and external P-gp substrate datasets,respectively,compared with 12 state-of-the-art methods.Furthermore,the interpretability analysis of all three molecular feature types offers comprehensive and complementary insights,demonstrating that MC-PGP effectively identifies key functional groups involved in P-gp interactions.These chemically intuitive insights provide valuable guidance for the design and optimization of drug candidates. 展开更多
关键词 P-GLYCOPROTEIN Deep learning Multimodal fusion Graph contrastive learning
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A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning
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作者 Yunjian Guo Kunpeng Li +4 位作者 Wei Yue Nam‑Young Kim Yang Li Guozhen Shen Jong‑Chul Lee 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期417-431,共15页
Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the pro... Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple scenarios.It features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance output.Through wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist movements.Remarkably,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various tasks.The system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and letters.The proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific training.Its utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication. 展开更多
关键词 Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction
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Real-Time Smart Meter Abnormality Detection Framework via End-to-End Self-Supervised Time-Series Contrastive Learning with Anomaly Synthesis
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作者 WANG Yixin LIANG Gaoqi +1 位作者 BI Jichao ZHAO Junhua 《南方电网技术》 北大核心 2025年第7期62-71,89,共11页
The rapid integration of Internet of Things(IoT)technologies is reshaping the global energy landscape by deploying smart meters that enable high-resolution consumption monitoring,two-way communication,and advanced met... The rapid integration of Internet of Things(IoT)technologies is reshaping the global energy landscape by deploying smart meters that enable high-resolution consumption monitoring,two-way communication,and advanced metering infrastructure services.However,this digital transformation also exposes power system to evolving threats,ranging from cyber intrusions and electricity theft to device malfunctions,and the unpredictable nature of these anomalies,coupled with the scarcity of labeled fault data,makes realtime detection exceptionally challenging.To address these difficulties,a real-time decision support framework is presented for smart meter anomality detection that leverages rolling time windows and two self-supervised contrastive learning modules.The first module synthesizes diverse negative samples to overcome the lack of labeled anomalies,while the second captures intrinsic temporal patterns for enhanced contextual discrimination.The end-to-end framework continuously updates its model with rolling updated meter data to deliver timely identification of emerging abnormal behaviors in evolving grids.Extensive evaluations on eight publicly available smart meter datasets over seven diverse abnormal patterns testing demonstrate the effectiveness of the proposed full framework,achieving average recall and F1 score of more than 0.85. 展开更多
关键词 abnormality detection cyber-physical security anomaly synthesis contrastive learning time-series
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Contrast Detection Learning Improves Visual Contrast Sensitivity of Cat 被引量:6
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作者 华田苗 王振华 +1 位作者 徐金旺 刁建刚 《Zoological Research》 CAS CSCD 北大核心 2010年第2期155-162,共8页
Psychological studies on human subjects show that contrast detection learning promote learner's sensitivity to visual stimulus contrast. The underlying neural mechanisms remain unknown. In this study, three cats (Fe... Psychological studies on human subjects show that contrast detection learning promote learner's sensitivity to visual stimulus contrast. The underlying neural mechanisms remain unknown. In this study, three cats (Felis catus) were trained to perform monocularly a contrast detection task by two-altemative forced choice method. The perceptual ability of each cat improved remarkably with learning as indicated by a significantly increased contrast sensitivity to visual stimuli. The learning effect displayed an evident specificity to the eye employed for learning but could partially transfer to the naive eye, prompting the possibility that contrast detection learning might cause neural plasticity before and after the information from both eyes are merged in the visual pathway. Further, the contrast sensitivity improvement was evident basically around the spatial frequency (SF) used for learning, which suggested that contrast detection learning effect showed, to some extent, a SF specificity. This study indicates that cat exhibits a property of contrast detection learning similar to human subjects and can be used as an animal model for subsequent investigations on the neural correlates that mediate learning-induced contrast sensitivity improvement in humans. 展开更多
关键词 VISUAL contrast detection LEARNING contrast sensitivity CAT
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Large Language Models With Contrastive Decoding Algorithm for Hallucination Mitigation in Low-Resource Languages
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作者 Zan Hongying Arifa Javed +2 位作者 Muhammad Abdullah Javed Rashid Muhammad Faheem 《CAAI Transactions on Intelligence Technology》 2025年第4期1104-1117,共14页
Neural machine translation(NMT)has advanced with deep learning and large-scale multilingual models,yet translating lowresource languages often lacks sufficient training data and leads to hallucinations.This often resu... Neural machine translation(NMT)has advanced with deep learning and large-scale multilingual models,yet translating lowresource languages often lacks sufficient training data and leads to hallucinations.This often results in translated content that diverges significantly from the source text.This research proposes a refined Contrastive Decoding(CD)algorithm that dynamically adjusts weights of log probabilities from strong expert and weak amateur models to mitigate hallucinations in lowresource NMT and improve translation quality.Advanced large language NMT models,including ChatGLM and LLaMA,are fine-tuned and implemented for their superior contextual understanding and cross-lingual capabilities.The refined CD algorithm evaluates multiple candidate translations using BLEU score,semantic similarity,and Named Entity Recognition accuracy.Extensive experimental results show substantial improvements in translation quality and a significant reduction in hallucination rates.Fine-tuned models achieve higher evaluation metrics compared to baseline models and state-of-the-art models.An ablation study confirms the contributions of each methodological component and highlights the effectiveness of the refined CD algorithm and advanced models in mitigating hallucinations.Notably,the refined methodology increased the BLEU score by approximately 30%compared to baseline models. 展开更多
关键词 ChatGLM contrastive decoding HALLUCINATION LLAMA LLM low resource NMT
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Robust Detection for Fisheye Camera Based on Contrastive Learning
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作者 Junzhe Zhang Lei Tang Xin Zhou 《Computers, Materials & Continua》 2025年第5期2643-2658,共16页
Fisheye cameras offer a significantly larger field of view compared to conventional cameras,making them valuable tools in the field of computer vision.However,their unique optical characteristics often lead to image d... Fisheye cameras offer a significantly larger field of view compared to conventional cameras,making them valuable tools in the field of computer vision.However,their unique optical characteristics often lead to image distortions,which pose challenges for object detection tasks.To address this issue,we propose Yolo-CaSKA(Yolo with Contrastive Learning and Selective Kernel Attention),a novel training method that enhances object detection on fisheye camera images.The standard image and the corresponding distorted fisheye image pairs are used as positive samples,and the rest of the image pairs are used as negative samples,which are guided by contrastive learning to help the distorted images find the feature vectors of the corresponding normal images,to improve the detection accuracy.Additionally,we incorporate the Selective Kernel(SK)attention module to focus on regions prone to false detections,such as image edges and blind spots.Finally,the mAP_(50) on the augmented KITTI dataset is improved by 5.5% over the original Yolov8,while the mAP_(50) on the WoodScape dataset is improved by 2.6% compared to OmniDet.The results demonstrate the performance of our proposed model for object detection on fisheye images. 展开更多
关键词 FISHEYE contrastive learning Yolov8 ATTENTION
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Event-Aware Sarcasm Detection in Chinese Social Media Using Multi-Head Attention and Contrastive Learning
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作者 Kexuan Niu Xiameng Si +1 位作者 Xiaojie Qi Haiyan Kang 《Computers, Materials & Continua》 2025年第10期2051-2070,共20页
Sarcasm detection is a complex and challenging task,particularly in the context of Chinese social media,where it exhibits strong contextual dependencies and cultural specificity.To address the limitations of existing ... Sarcasm detection is a complex and challenging task,particularly in the context of Chinese social media,where it exhibits strong contextual dependencies and cultural specificity.To address the limitations of existing methods in capturing the implicit semantics and contextual associations in sarcastic expressions,this paper proposes an event-aware model for Chinese sarcasm detection,leveraging a multi-head attention(MHA)mechanism and contrastive learning(CL)strategies.The proposed model employs a dual-path Bidirectional Encoder Representations from Transformers(BERT)encoder to process comment text and event context separately and integrates an MHA mechanism to facilitate deep interactions between the two,thereby capturing multidimensional semantic associations.Additionally,a CL strategy is introduced to enhance feature representation capabilities,further improving the model’s performance in handling class imbalance and complex contextual scenarios.The model achieves state-of-the-art performance on the Chinese sarcasm dataset,with significant improvements in accuracy(79.55%),F1-score(84.22%),and an area under the curve(AUC,84.35%). 展开更多
关键词 Sarcasm detection event-aware multi-head attention contrastive learning NLP
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Dual-Task Contrastive Meta-Learning for Few-Shot Cross-Domain Emotion Recognition
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作者 Yujiao Tang Yadong Wu +2 位作者 Yuanmei He Jilin Liu Weihan Zhang 《Computers, Materials & Continua》 2025年第2期2331-2352,共22页
Emotion recognition plays a crucial role in various fields and is a key task in natural language processing (NLP). The objective is to identify and interpret emotional expressions in text. However, traditional emotion... Emotion recognition plays a crucial role in various fields and is a key task in natural language processing (NLP). The objective is to identify and interpret emotional expressions in text. However, traditional emotion recognition approaches often struggle in few-shot cross-domain scenarios due to their limited capacity to generalize semantic features across different domains. Additionally, these methods face challenges in accurately capturing complex emotional states, particularly those that are subtle or implicit. To overcome these limitations, we introduce a novel approach called Dual-Task Contrastive Meta-Learning (DTCML). This method combines meta-learning and contrastive learning to improve emotion recognition. Meta-learning enhances the model’s ability to generalize to new emotional tasks, while instance contrastive learning further refines the model by distinguishing unique features within each category, enabling it to better differentiate complex emotional expressions. Prototype contrastive learning, in turn, helps the model address the semantic complexity of emotions across different domains, enabling the model to learn fine-grained emotions expression. By leveraging dual tasks, DTCML learns from two domains simultaneously, the model is encouraged to learn more diverse and generalizable emotions features, thereby improving its cross-domain adaptability and robustness, and enhancing its generalization ability. We evaluated the performance of DTCML across four cross-domain settings, and the results show that our method outperforms the best baseline by 5.88%, 12.04%, 8.49%, and 8.40% in terms of accuracy. 展开更多
关键词 contrastive learning emotion recognition cross-domain learning DUAL-TASK META-LEARNING
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Echo contrast medium:How the use of contrast echocardiography(ultrasound contrast agents)can improve patient care
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作者 Kevan English 《World Journal of Methodology》 2025年第3期32-37,共6页
Conventional echocardiography can sometimes pose a challenge to diagnosis due to sub-optimal images.Ultrasound contrast agents(UCAs)have been shown to drastically enhance imaging quality,particularly depicting the lef... Conventional echocardiography can sometimes pose a challenge to diagnosis due to sub-optimal images.Ultrasound contrast agents(UCAs)have been shown to drastically enhance imaging quality,particularly depicting the left ventricular endocardial borders.Their use during echocardiography has become a valuable tool in non-invasive diagnostics.UCAs provide higher-quality images that may ultimately reduce the length of hospital stays and improve patient care.The higher cost associated with UCAs in many situations has been an impediment to frequent use.However,when used as an initial diagnostic test,UCA during rest echocardiogram is more cost-effective than the traditional diagnostic approach,which frequently includes multiple tests and imaging studies to make an accurate diagnosis.They can be easily performed across multiple patient settings and provide optimal images that allow clinicians to make sound medical decisions.This consequently allows for better diagnostic accuracies and improvement in patient care. 展开更多
关键词 Ultrasound contrast agents ECHOCARDIOGRAPHY Myocardial perfusion ULTRASOUND Left ventricle OPTISON DEFINITY SONAZOID Lumason
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FedCLCC:A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing
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作者 Kangning Yin Xinhui Ji +1 位作者 Yan Wang Zhiguo Wang 《Defence Technology(防务技术)》 2025年第1期80-93,共14页
Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure ... Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure challenges in edge environments.However,the diversity of clients in edge cloud computing presents significant challenges for FL.Personalized federated learning(pFL)received considerable attention in recent years.One example of pFL involves exploiting the global and local information in the local model.Current pFL algorithms experience limitations such as slow convergence speed,catastrophic forgetting,and poor performance in complex tasks,which still have significant shortcomings compared to the centralized learning.To achieve high pFL performance,we propose FedCLCC:Federated Contrastive Learning and Conditional Computing.The core of FedCLCC is the use of contrastive learning and conditional computing.Contrastive learning determines the feature representation similarity to adjust the local model.Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling.Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms. 展开更多
关键词 Federated learning Statistical heterogeneity Personalized model Conditional computing contrastive learning
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Equilibrium phase images of the liver using a contrast-enhancement boost instead of the portal vein phase
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作者 Yuji Tachibana Kenichiro Otsuka +1 位作者 Tomoaki Shiroo Yoshiki Asayama 《World Journal of Radiology》 2025年第2期28-37,共10页
BACKGROUND Three-phase dynamic computed tomography imaging is particularly useful in the liver region.However,dynamic imaging with contrast media has the disadvantage of increased radiation exposure due to multiple im... BACKGROUND Three-phase dynamic computed tomography imaging is particularly useful in the liver region.However,dynamic imaging with contrast media has the disadvantage of increased radiation exposure due to multiple imaging sessions.We hypothesized that the contrast enhancement boost(CE-boost)technique could be used to enhance the contrast in equilibrium phase(EP)images and produce enhancement similar to that of portal vein phase(PVP)images,and if this is possible,EP imaging could play the same role as PVP imaging.We also speculated that this might allow the conversion of three-phase dynamic imaging to biphasic dynamic imaging,reducing patients’radiation exposure.AIM To determine if the CE-boost of EP,CE-boost(EP)is useful compared to a conventional image.METHODS We retrospectively analyzed the cases of 52 patients who were diagnosed with liver cancer between January 2016 and October 2022 at our institution.From these computed tomography images,CE-boost images were generated from the EP and plane images.We compared the PVP,EP,and CE-boost(EP)for blood vessels and hepatic parenchyma based on the contrast-to-noise ratio(CNR),signal-to-noise ratio,and figure-of-merit(FOM).Visual assessments were also performed for vessel visualization,lesion conspicuity,and image noise.RESULTS The CE-boost(EP)images showed significant superiority compared to the PVP images in the CNR,signal-to-noise ratio,and FOM except regarding the hepatic parenchyma.No significant differences were detected in CNR or FOM comparisons within the hepatic parenchyma(P=0.62,0.67).The comparison of the EP and CE-boost(EP)images consistently favored CE-boost(EP).Regarding the visual assessment,the CE-boost(EP)images were significantly superior to the PVP images in lesion conspicuity,and the PVP in image noise.The CE-boost(EP)images were significantly better than the EP images in the vessel visualization of segmental branches of the portal vein and lesion conspicuity,and the EP in image noise.CONCLUSION The image quality of CE-boost(EP)images was comparable or superior to that of conventional PVP and EP.CEboost(EP)images might provide information comparable to the conventional PVP. 展开更多
关键词 LIVER Computed tomography contrast enhancement boost Image quality Lesion conspicuity
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