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Part-Whole Relational Few-Shot 3D Point Cloud Semantic Segmentation
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作者 Shoukun Xu Lujun Zhang +2 位作者 Guangqi Jiang Yining Hua Yi Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3021-3039,共19页
This paper focuses on the task of few-shot 3D point cloud semantic segmentation.Despite some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation an... This paper focuses on the task of few-shot 3D point cloud semantic segmentation.Despite some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation and inaccurate semantic discrimination.To tackle these issues,we first leverage part-whole relationships into the task of 3D point cloud semantic segmentation to capture semantic integrity,which is empowered by the dynamic capsule routing with the module of 3D Capsule Networks(CapsNets)in the embedding network.Concretely,the dynamic routing amalgamates geometric information of the 3D point cloud data to construct higher-level feature representations,which capture the relationships between object parts and their wholes.Secondly,we designed a multi-prototype enhancement module to enhance the prototype discriminability.Specifically,the single-prototype enhancement mechanism is expanded to the multi-prototype enhancement version for capturing rich semantics.Besides,the shot-correlation within the category is calculated via the interaction of different samples to enhance the intra-category similarity.Ablation studies prove that the involved part-whole relations and proposed multi-prototype enhancement module help to achieve complete object segmentation and improve semantic discrimination.Moreover,under the integration of these two modules,quantitative and qualitative experiments on two public benchmarks,including S3DIS and ScanNet,indicate the superior performance of the proposed framework on the task of 3D point cloud semantic segmentation,compared to some state-of-the-art methods. 展开更多
关键词 Few-shot point cloud semantic segmentation CapsNets
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Glacier area change (1993-2019) and its relationship to debris cover, proglacial lakes, and morphological parameters in the Chandra-Bhaga Basin, Western Himalaya, India
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作者 VATSAL Sarvagya AZAM Mohd Farooq +5 位作者 BHARDWAJ Anshuman MANDAL Arindan BAHUGUNA Ishmohan RAMANATHAN Alagappan RAJU N.Janardhana TOMAR Sangita Singh 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1287-1306,共20页
Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years... Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered glaciers.Area changes are estimated for three periods:1993-2000,2000-2010,and 2010-2019.The total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in 2019.The mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and 2019.It is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during 1993-2019.Extensive field surveys on Chhota Shigri,Panchi II,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets.Controls of various morphological parameters on retreat were also analyzed.It is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin. 展开更多
关键词 GLACIER Area change Debris cover MORPHOLOGY Proglacial lake
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Efficient Electromagnetic Wave Absorption and Thermal Infrared Stealth in PVTMS@MWCNT Nano‑Aerogel via Abundant Nano‑Sized Cavities and Attenuation Interfaces
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作者 Haoyu Ma Maryam Fashandi +5 位作者 Zeineb Ben Rejeb Xin Ming Yingjun Liu Pengjian Gong Guangxian Li Chul B.Park 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期370-383,共14页
Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT... Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work. 展开更多
关键词 Nano-pore size Heterogeneous interface Electromagnetic wave absorption Thermal infrared stealth Nano-aerogel
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Prediction of treatment response to antipsychotic drugs for precision medicine approach to schizophrenia:randomized trials and multiomics analysis
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作者 Liang-Kun Guo Yi Su +24 位作者 Yu-Ya-Nan Zhang Hao Yu Zhe Lu Wen-Qiang Li Yong-Feng Yang Xiao Xiao Hao Yan Tian-Lan Lu Jun Li Yun-Dan Liao Zhe-Wei Kang Li-Fang Wang Yue Li Ming Li Bing Liu Hai-Liang Huang Lu-Xian Lv Yin Yao Yun-Long Tan Gerome Breen Ian Everall Hong-Xing Wang Zhuo Huang Dai Zhang Wei-Hua Yue 《Military Medical Research》 SCIE CAS CSCD 2024年第1期19-33,共15页
Background:Choosing the appropriate antipsychotic drug(APD)treatment for patients with schizophrenia(SCZ)can be challenging,as the treatment response to APD is highly variable and difficult to predict due to the lack ... Background:Choosing the appropriate antipsychotic drug(APD)treatment for patients with schizophrenia(SCZ)can be challenging,as the treatment response to APD is highly variable and difficult to predict due to the lack of effective biomarkers.Previous studies have indicated the association between treatment response and genetic and epigenetic factors,but no effective biomarkers have been identified.Hence,further research is imperative to enhance precision medicine in SCZ treatment.Methods:Participants with SCZ were recruited from two randomized trials.The discovery cohort was recruited from the CAPOC trial(n=2307)involved 6 weeks of treatment and equally randomized the participants to the Olanzapine,Risperidone,Quetiapine,Aripiprazole,Ziprasidone,and Haloperidol/Perphenazine(subsequently equally assigned to one or the other)groups.The external validation cohort was recruited from the CAPEC trial(n=1379),which involved 8 weeks of treatment and equally randomized the participants to the Olanzapine,Risperidone,and Aripiprazole groups.Additionally,healthy controls(n=275)from the local community were utilized as a genetic/epigenetic reference.The genetic and epigenetic(DNA methylation)risks of SCZ were assessed using the polygenic risk score(PRS)and polymethylation score,respectively.The study also examined the genetic-epigenetic interactions with treatment response through differential methylation analysis,methylation quantitative trait loci,colocalization,and promoteranchored chromatin interaction.Machine learning was used to develop a prediction model for treatment response,which was evaluated for accuracy and clinical benefit using the area under curve(AUC)for classification,R^(2) for regression,and decision curve analysis.Results:Six risk genes for SCZ(LINC01795,DDHD2,SBNO1,KCNG2,SEMA7A,and RUFY1)involved in cortical morphology were identified as having a genetic-epigenetic interaction associated with treatment response.The developed and externally validated prediction model,which incorporated clinical information,PRS,genetic risk score(GRS),and proxy methylation level(proxyDNAm),demonstrated positive benefits for a wide range of patients receiving different APDs,regardless of sex[discovery cohort:AUC=0.874(95%CI 0.867-0.881),R^(2)=0.478;external validation cohort:AUC=0.851(95%CI 0.841-0.861),R^(2)=0.507].Conclusions:This study presents a promising precision medicine approach to evaluate treatment response,which has the potential to aid clinicians in making informed decisions about APD treatment for patients with SCZ.Trial registration Chinese Clinical Trial Registry(https://www.chictr.org.cn/),18 Aug 2009 retrospectively registered:CAPOC-ChiCTR-RNC-09000521(https://www.chictr.org.cn/showproj.aspx?proj=9014),CAPEC-ChiCTRRNC-09000522(https://www.chictr.org.cn/showproj.aspx?proj=9013). 展开更多
关键词 SCHIZOPHRENIA Antipsychotic drug Treatment response Prediction model GENETICS EPIGENETICS
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Do medical students studying in the United Kingdom have an adequate factual knowledge of basic life support? 被引量:2
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作者 Robert D.Willmore Damjan Veljanoski +26 位作者 Feray Ozdes Bethan Stephens James Mooney Seamus G.Crumley Arpan Doshi Philippa Davies Shreya Badhrinarayanan Emily Day Kristian Tattam April Wilson Nathan Crang Lorna Green Craig A.Mounsey Howell Fu Joseph Williams Michelle S.D'souza Dhanya Sebastian Liam A.Mcgiveron Matthew G.Percy James Cohen Imogen J.John Alice Lethbridge Imogen Watkins Omar Amin Mubasher A.Qamar John Gerrard Hanrahan Emily Cramond-Wong 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2019年第2期75-80,共6页
BACKGROUND: Healthcare professionals have a duty to maintain basic life support(BLS) skills. This study aims to evaluate medical students' factual knowledge of BLS and the training they receive.METHODS: A cross-se... BACKGROUND: Healthcare professionals have a duty to maintain basic life support(BLS) skills. This study aims to evaluate medical students' factual knowledge of BLS and the training they receive.METHODS: A cross-sectional, closed-response questionnaire was distributed to the fi rst-and fourth-year students studying at institutions in the United Kingdom. The paper questionnaire sought to quantify respondent's previous BLS training, factual knowledge of the BLS algorithm using five multiple choice questions(MCQs), and valuate their desire for further BLS training. Students received 1 point for each correctly identifi ed answer to the 5 MCQ's.RESULTS: A total of 3,732 complete responses were received from 21 medical schools. Eighty percent(n=2,999) of students completed a BLS course as part of their undergraduate medical studies. There was a signifi cant difference(P<0.001) in the percentage of the fourth-year students selecting the correct answer in all the MCQ's compared to the fi rst-year students except in identifyingthe correct depth of compressions required during CPR(P=0.095). Overall 10.3%(95% CI 9.9% to 10.7%) of respondents correctly identified the answer to 5 MCQ's on BLS: 9% of the first-year students(n=194) and 12% of the fourth-year students(n=190). On an institutional level the proportion of students answering all MCQ's correctly ranged from 2% to 54% at different universities. Eighty-one percent of students(n=3,031) wished for more BLS training in their curriculum.CONCLUSION: Factual knowledge of BLS is poor among medical students in the UK. There is a disparity in standards of knowledge across institutions and respondents indicating that they would like more training. 展开更多
关键词 EMERGENCY Medicine Basic life support Medical education RESUSCITATION
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Sampled-data control through model-free reinforcement learning with effective experience replay 被引量:2
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作者 Bo Xiao H.K.Lam +4 位作者 Xiaojie Su Ziwei Wang Frank P.-W.Lo Shihong Chen Eric Yeatman 《Journal of Automation and Intelligence》 2023年第1期20-30,共11页
Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can lear... Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can learn the control strategy directly in a model-free way instead of investigating the dynamic model of the environment.In the paper,we propose the sampled-data RL control strategy to reduce the computational demand.In the sampled-data control strategy,the whole control system is of a hybrid structure,in which the plant is of continuous structure while the controller(RL agent)adopts a discrete structure.Given that the continuous states of the plant will be the input of the agent,the state–action value function is approximated by the fully connected feed-forward neural networks(FCFFNN).Instead of learning the controller at every step during the interaction with the environment,the learning and acting stages are decoupled to learn the control strategy more effectively through experience replay.In the acting stage,the most effective experience obtained during the interaction with the environment will be stored and during the learning stage,the stored experience will be replayed to customized times,which helps enhance the experience replay process.The effectiveness of proposed approach will be verified by simulation examples. 展开更多
关键词 Reinforcement learning Neural networks Sampled-data control MODEL-FREE Effective experience replay
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Assessment methods and services for older people with cancer in the United Kingdom
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作者 Tania Kalsi Danielle Harari 《World Journal of Clinical Oncology》 2020年第3期152-161,共10页
BACKGROUND National cancer strategy calls for comprehensive assessments for older people but current practice across the United Kingdom is not well described.AIM To identify current assessment methods and access to re... BACKGROUND National cancer strategy calls for comprehensive assessments for older people but current practice across the United Kingdom is not well described.AIM To identify current assessment methods and access to relevant supporting services for older people with cancer.METHODS A web-based survey(SurveyMonkey)targeting health professionals(oncologists,cancer surgeons,geriatricians,nurses and allied health professionals)was distributed January-April 2016 via United Kingdom nationally recognised professional societies.Responses were analysed in frequencies and percentages.Chi Square was used to compare differences in responses between different groups.RESULTS 640 health care professionals responded.Only 14.1%often/always involved geriatricians and 52.0%often/always involved general practitioners in assessments.When wider assessments were used,they always/often influenced decision-making(40.5%)or at least sometimes(34.1%).But 30.5%-44.3%did not use structured assessment methods.Most clinicians favoured clinical history taking.Few used scoring tools and few wished to use them in the future.Most had urgent access to palliative care but only a minority had urgent access to other key supporting professionals(e.g.geriatricians,social workers,psychiatry).69.6%were interested in developing Geriatric Oncology services with geriatricians.CONCLUSION There is variability in assessment methods for older people with cancer across the United Kingdom and variation in perceived access to supporting services.Clinical history taking was preferred to scoring systems.Fostering closer links with geriatricians appears supported. 展开更多
关键词 Geriatric assessment ELDERLY OLDER CANCER Support SERVICES
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An Integrated Framework to Analyze Local Decision Making and Adaptation to Sea Level Rise in Coastal Regions in Selsey (UK), Broward County (USA), and Santos (Brazil)
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作者 J. Marengo F. Muller-Karger +14 位作者 M. Pelling C. J. Reynolds S. B. Merrill L. H. Nunes S. Paterson A. J. Gray J. T. Lockman J. Kartez F. A. Moreira R. Greco J. Harari C. R. G. Souza L. M. Alves E. K. Hosokawa E. K. Tabuchi 《American Journal of Climate Change》 2017年第2期403-424,共22页
One of the clear signals of the ongoing climate change is sea level rise (SLR). Normal oceanic tides superimposed on a rising sea level and coastal flooding will affect many coastal communities. An international colla... One of the clear signals of the ongoing climate change is sea level rise (SLR). Normal oceanic tides superimposed on a rising sea level and coastal flooding will affect many coastal communities. An international collaboration among Brazil, the United Kingdom, and the United States was designed to evaluate local decision making processes and to open space for local urban managers to reflect on possible actions toward adaption to sea level rise given the historical constraints imposed by administrative and institutional structures. This project focused on the processes that shape adaptation of three coastal communities in three countries. It worked jointly with these communities in defining the problem, examining risks, and understanding the benefits and obstacles that may hinder implementation of adaptation options. The framework was co-designed by an interdisciplinary team that incorporated social and natural scientists from the three countries, including local government officials. The study addressed 1) evaluation of adaptive capacity through participant surveys and 2) physical and cost impact simulations using geospatial models of the built infrastructure and implementation of adaptation options under different hazard scenarios, including 50 and 100-year sea level rise projections and severe storms. Based on the surveys’ results, there is a clear sense of the awareness of each community of the risk of floods due to intense storms, and of the usefulness of engaging early in a process that promotes the understanding of risks, impacts, and costs. A majority of workshop participants prioritized pursuing physical and green infrastructure actions now or within coming years or decades. A positive common aspect of the three sites was the commitment shown by the stakeholders in taking part in the process and evaluating which adaptation measures could be more effective in their cities. While in the US and UK structural solutions and voluntary buyouts were prioritized for the future, Brazil prioritized structural solutions and ecosystems restoration and not voluntary buyouts. All of these are choices to increase resiliency against sea level rise that have a high benefit-cost ratio. The Adaptive Capacity Index (ACI) results illustrate barriers to adaptation action, including technical, economic and political issues that reveal inequalities in adaptive capacity among case studies. 展开更多
关键词 Sea Level RISE VULNERABILITY ADAPTATION IMPACTS CLIMATE Change
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The prevalence,associated factors,and impact of urinary incontinence in pregnant and postpartum women in Nanjing,China:A cross-sectional study
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作者 Xiaowei Yang Lynn Sayer +1 位作者 Sam Bassett Sue Woodward 《Asian Journal of Urology》 CSCD 2023年第3期337-343,共7页
Objective:Urinary incontinence(UI)is highly prevalent in antenatal and postnatal women while the prevalence of UI varied largely from 3.84%to 38.65%.This study was to assess the prevalence of UI,the associated factors... Objective:Urinary incontinence(UI)is highly prevalent in antenatal and postnatal women while the prevalence of UI varied largely from 3.84%to 38.65%.This study was to assess the prevalence of UI,the associated factors,and the impact of UI on daily life in pregnant and postpartum women in Nanjing,China.Methods:The prevalence of UI and the impact of UI on life were assessed by the validated Chinese version of International Consultation on Incontinence Questionnaire-urinary incontinence-short form and the validated Chinese version of urinary incontinence quality of life.The associated factors were estimated by using logistic regression analysis.Results:UI affected 37.80%of pregnant women and 16.41%of postpartum women of the study population.Among the pregnant participants,the prevalence rates of stress UI,urge UI,and mixed UI were 25.77%,4.47%,and 7.10%,respectively.Among the postpartum women,the prevalence rates of stress UI,urge UI,and mixed UI were 11.15%,1.92%,and 2.69%,respectively.In both pregnant women and postpartum women,vaginal delivery had significantly increased the odds of reporting UI(p=0.007,p=0.003,respectively).The impact of UI on daily life was significantly greater in postpartum women compared to pregnant women especially in social embarrassment(p=0.000).Conclusion:The prevalence rates of UI were high in pregnant women in Nanjing,China.Vaginal delivery significantly increased odds of reporting UI.UI has a great impact on pregnant and postpartum women’s life,especially in social embarrassment. 展开更多
关键词 Postpartum women Pregnant women PREVALENCE Risk factor Urinary incontinence
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Corneal astigmatic outcomes after femtosecond laser-assisted cataract surgery combined with surface penetrating arcuate keratotomies
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作者 Nick Stanojcic David O’Brart +5 位作者 Chris Hull Vijay Wagh Elodie Azan Mani Bhogal Scott Robbie Ji-Peng Olivia Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第7期1084-1092,共9页
AIM:To evaluate corneal astigmatic outcomes of femtosecond laser-assisted arcuate keratotomies(FAKs)combined with femtosecond-laser assisted cataract surgery(FLACS)over 12mo follow-up.METHODS:Totally 145 patients with... AIM:To evaluate corneal astigmatic outcomes of femtosecond laser-assisted arcuate keratotomies(FAKs)combined with femtosecond-laser assisted cataract surgery(FLACS)over 12mo follow-up.METHODS:Totally 145 patients with bilateral cataracts and no ocular co-morbidities were recruited to a singlecentre,single-masked,prospective randomized controlled trial(RCT)comparing two monofocal hydrophobic acrylic intraocular lenses.Eyes with corneal astigmatism(CA)of>0.8 dioptres(D)received unpaired,unopened,surface penetrating FAKs at the time of FLACS.Visual acuity,subjective refraction and Scheimpflug tomography were recorded at 1,6,and 12mo.Alpins vectoral analyses were performed.RESULTS:Fifty-one patients(61 eyes),mean age 68.2±9.6y[standard deviation(SD)],received FAKs.Sixty eyes were available for analysis,except at 12mo when 59 attended.There were no complications due to FAKs.Mean pre-operative CA was 1.13±0.20 D.There was a reduction of astigmatism at all post-operative visits(residual CA 1mo:0.85±0.42 D,P=0.0001;6mo:0.86±0.35 D,P=0001;and 12mo:0.90±0.39,P=0.0001).Alpins indices remained stable over 12mo.Overall,the cohort was under-corrected at all time points.At 12mo,61%of eyes were within±15 degrees of pre-operative astigmatic meridian.CONCLUSION:Unpaired unopened penetrating FAKs combined with on-axis phacoemulsification are safe but minimally effective.CA is largely under-corrected in this cohort using an existing unmodified nomogram.The effect of arcuate keratotomies on CA remained stable over 12mo. 展开更多
关键词 femtosecond cataract surgery astigmatic keratotomy laser cataract surgery femtosecond-laser assisted cataract surgery arcuate keratotomy
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Regression of recurrent granulosa cell tumor liver metastases following selective internal radiation therapy
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作者 Omar A Mownah John D Leahy +2 位作者 Jeffrey Summers Stephen M Gregory Nigel D Heaton 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第4期406-408,共3页
Granulosa cell tumor(GCT)is the most common sex cordstromal tumor,comprising 5%of all ovarian malignancies[1].The disease course is indolent,and the majority of cases present at stage 1.However,metastases may develop ... Granulosa cell tumor(GCT)is the most common sex cordstromal tumor,comprising 5%of all ovarian malignancies[1].The disease course is indolent,and the majority of cases present at stage 1.However,metastases may develop with potential sites being peritoneum,lung,brain,liver and bone[2].Due to the rarity of the disease,published evidence for management of granulosa cell tumor liver metastases(GCTLM)is limited.Surgical resection is the optimal treatment in instances where there is a high chance of achieving complete resection[3].With regards to unresectable GCTLM there is a paucity of evidence to guide treatment strategy. 展开更多
关键词 METASTASES LIVER LUNG
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A new software for automated counting of glistenings in intraocular lenses in vivo
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作者 Nick Stanojcic Christopher C.Hull +2 位作者 Eduardo Mangieri Nathan Little David O’Brart 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第8期1237-1242,共6页
AIM:To assess the performance of a bespoke software for automated counting of intraocular lens(IOL)glistenings in slit-lamp images.METHODS:IOL glistenings from slit-lamp-derived digital images were counted manually an... AIM:To assess the performance of a bespoke software for automated counting of intraocular lens(IOL)glistenings in slit-lamp images.METHODS:IOL glistenings from slit-lamp-derived digital images were counted manually and automatically by the bespoke software.The images of one randomly selected eye from each of 34 participants were used as a training set to determine the threshold setting that gave the best agreement between manual and automatic grading.A second set of 63 images,selected using randomised stratified sampling from 290 images,were used for software validation.The images were obtained using a previously described protocol.Software-derived automated glistenings counts were compared to manual counts produced by three ophthalmologists.RESULTS:A threshold value of 140 was determined that minimised the total deviation in the number of glistenings for the 34 images in the training set.Using this threshold value,only slight agreement was found between automated software counts and manual expert counts for the validating set of 63 images(κ=0.104,95%CI,0.040-0.168).Ten images(15.9%)had glistenings counts that agreed between the software and manual counting.There were 49 images(77.8%)where the software overestimated the number of glistenings.CONCLUSION:The low levels of agreement show between an initial release of software used to automatically count glistenings in in vivo slit-lamp images and manual counting indicates that this is a non-trivial application.Iterative improvement involving a dialogue between software developers and experienced ophthalmologists is required to optimise agreement.The results suggest that validation of software is necessary for studies involving semi-automatic evaluation of glistenings. 展开更多
关键词 new software automated counting glistenings intraocular lenses slit-lamp images
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Synaptopathy in CHMP2B frontotemporal dementia highlights the synaptic vesicle cycle as a therapeutic target
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作者 Miranda Robbins Emma L.Clayton 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期315-316,共2页
Amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD)are both devastating neurodegenerative conditions.Despite affecting different regions of the nervous system(FTD affecting primarily the frontal and tem... Amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD)are both devastating neurodegenerative conditions.Despite affecting different regions of the nervous system(FTD affecting primarily the frontal and temporal lobes,whilst ALS presents with motor neuron loss),there is significant overlap between these conditions in terms of genetics,pathology,and disease mechanisms,and they are therefore often grouped as a spectrum of symptoms under the heading FTD/ALS(Abramzon et al.,2020).Significantly,there is currently no cure for ALS or FTD.However,recent mechanistic insight points to a novel pathway to target for potential therapeutic intervention. 展开更多
关键词 THERAPEUTIC PATHOLOGY
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A Deep Learning Driven Feature Based Steganalysis Approach
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作者 Yuchen Li Baohong Ling +2 位作者 Donghui Hu Shuli Zheng Guoan Zhang 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2213-2225,共13页
The goal of steganalysis is to detect whether the cover carries the secret information which is embedded by steganographic algorithms.The traditional ste-ganalysis detector is trained on the stego images created by a ... The goal of steganalysis is to detect whether the cover carries the secret information which is embedded by steganographic algorithms.The traditional ste-ganalysis detector is trained on the stego images created by a certain type of ste-ganographic algorithm,whose detection performance drops rapidly when it is applied to detect another type of steganographic algorithm.This phenomenon is called as steganographic algorithm mismatch in steganalysis.To resolve this pro-blem,we propose a deep learning driven feature-based approach.An advanced steganalysis neural network is used to extract steganographic features,different pairs of training images embedded with steganographic algorithms can obtain diverse features of each algorithm.Then a multi-classifier implemented as lightgbm is used to predict the matching algorithm.Experimental results on four types of JPEG steganographic algorithms prove that the proposed method can improve the detection accuracy in the scenario of steganographic algorithm mismatch. 展开更多
关键词 Image steganalysis algorithm mismatch convolutional neural network JPEG images
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Orientation in upper gastrointestinal endoscopy—the only way is up
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作者 Arun Sivananthan Georgina Kerry +2 位作者 Ara Darzi Kinesh Patel Nisha Patel 《World Journal of Gastrointestinal Endoscopy》 2023年第3期146-152,共7页
BACKGROUND Oesophagogastroduodenoscopy is the gold standard investigation for the upper gastrointestinal(UGI)tract.Orientation during endoscopy is challenging and United Kingdom training focusses on technical competen... BACKGROUND Oesophagogastroduodenoscopy is the gold standard investigation for the upper gastrointestinal(UGI)tract.Orientation during endoscopy is challenging and United Kingdom training focusses on technical competence and procedural safety.The reported location of UGI pathologies is crucial to post-endoscopic planning.AIM To evaluate endoscopists’ability to spatially orientate themselves within the UGI tract.METHODS A cross sectional descriptive study elicited,using an anonymised survey,the ability of endoscopists to orientate themselves within the UGI tract.The primary outcome was percentage of correct answers from all surveyed;secondary outcomes were percentage of correct answers from experienced vs novice endoscopists.Pearson’sχ2 test was applied to compare groups.RESULTS Of 188 respondents,86 were experienced endoscopists having completed over 1000 endoscopies.44.4%of respondents correctly identified the anterior stomach and 47.3%correctly identified the posterior of the second part of the duodenum(D2).Experienced endoscopists were significantly more likely than novice to identify the anterior stomach correctly[61.6%vs 31.3%,X2(1,n=188)=11.10,P=0.001].There was no significant difference between the two groups in identifying the posterior of D2.CONCLUSION The majority of endoscopists surveyed were unable to identify key landmarks within the UGI tract.Endoscopic orientation appears to improve with experience yet there are some areas still not well recognised.This has potential considerable impact on post-endoscopic management of patients with posterior duodenal ulcers being more likely to perforate and associated with a higher rebleeding risk.We suggest the development of a consensus statement on endoscopic description. 展开更多
关键词 ENDOSCOPY ORIENTATION Upper gastrointestinal Gastric cancer Duodenal ulcer
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Secure Federated Learning over Wireless Communication Networks with Model Compression
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作者 DING Yahao Mohammad SHIKH-BAHAEI +2 位作者 YANG Zhaohui HUANG Chongwen YUAN Weijie 《ZTE Communications》 2023年第1期46-54,共9页
Although federated learning(FL)has become very popular recently,it is vulnerable to gradient leakage attacks.Recent studies have shown that attackers can reconstruct clients’private data from shared models or gradien... Although federated learning(FL)has become very popular recently,it is vulnerable to gradient leakage attacks.Recent studies have shown that attackers can reconstruct clients’private data from shared models or gradients.Many existing works focus on adding privacy protection mechanisms to prevent user privacy leakages,such as differential privacy(DP)and homomorphic encryption.These defenses may cause an increase in computation and communication costs or degrade the performance of FL.Besides,they do not consider the impact of wireless network resources on the FL training process.Herein,we propose weight compression,a defense method to prevent gradient leakage attacks for FL over wireless networks.The gradient compression matrix is determined by the user’s location and channel conditions.We also add Gaussian noise to the compressed gradients to strengthen the defense.This joint learning of wireless resource allocation and weight compression matrix is formulated as an optimization problem with the objective of minimizing the FL loss function.To find the solution,we first analyze the convergence rate of FL and quantify the effect of the weight matrix on FL convergence.Then,we seek the optimal resource block(RB)allocation by exhaustive search or ant colony optimization(ACO)and then use the CVX toolbox to obtain the optimal weight matrix to minimize the optimization function.The simulation results show that the optimized RB can accelerate the convergence of FL. 展开更多
关键词 federated learning(FL) data leakage from gradient resource block(RB)allocation
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Investigating the Effect of COVID-19 Infection on Professional Athletes’ Post-Infection with a Focus on Fatigue and Chronic Fatigue Syndrome
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作者 Reza Sarwary Manahil Tareen +3 位作者 Zain Hashmi Sonia Thavanessan Tina Patel Mevhibe Hocaoglu 《Journal of Biosciences and Medicines》 2023年第12期261-274,共12页
Introduction and Objectives: COVID-19 has been reported to cause long-term sequela including persistent fatigue and Chronic Fatigue Syndrome (CFS) in the general population. However, it remains to be seen if similar e... Introduction and Objectives: COVID-19 has been reported to cause long-term sequela including persistent fatigue and Chronic Fatigue Syndrome (CFS) in the general population. However, it remains to be seen if similar effects are observed in an athlete population. The aetiology and pathophysiology are poorly understood but is thought to be multi-factorial. Patient reported outcome measures are commonly used to improve patient-centred outcomes (PROMs). They are essential to assess patient quality of life post-COVID infection. This paper aims to assess the effect of COVID-19 on athletes’ long-term fatigue and CFS and identify the PROMs used to characterise this. Methodology: Articles were selected for extraction based on the eligibility criteria and PRISMA guidelines. The inclusion criteria required papers to assess competitive athletes over eighteen years of age who were clinically diagnosed with COVID-19. Articles were extracted to assess different variables including type of sport, type of athlete and ethnicity. Key terms were obtained using MeSH trees and utilised with Web of Science and NCBI Pubmed. Papers were graded by quality using the Hawker quality assessment tool. Results and Discussion: Forty articles (N = 40) were identified for full-text screening (N = 8). Eight were selected for extraction based on the eligibility criteria. Data was obtained on athlete characteristics, sport characteristics, properties of PROM measurement techniques and fatigue presentation. Male athletes were found to be 10% - 50% more likely than female athletes to suffer from persistent fatigue symptoms (N = 2). Persistent fatigue was present in 9% - 10% Athletes from mixed backgrounds and genders (N = 2). Initial fatigue was documented to be between 47% - 56% (N = 2). A heterogenous range of PROMs were utilised to assess symptoms including fatigue and excluded emotional or mental fatigue. Conclusion: COVID-19 is associated with signs of persisting fatigue and potentially CFS in athlete populations. More work needs to be done to develop standardised and validated PROMs specific to CFS. 展开更多
关键词 COVID-19 FIBROMYALGIA ATHLETE Quality of Life Patient Reported Outcome Measures
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Role of pulmonary perfusion magnetic resonance imaging for the diagnosis of pulmonary hypertension:A review
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作者 Miriam Lacharie Adriana Villa +3 位作者 Xenios Milidonis Hadeer Hasaneen Amedeo Chiribiri Giulia Benedetti 《World Journal of Radiology》 2023年第9期256-273,共18页
Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-bas... Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-based techniques are standard imaging modalities to non-invasively diagnose CTEPH,however these are limited by radiation exposure,subjective qualitative bias,and lack of cardiac functional assessment.This review aims to assess the methodology,diagnostic accuracy of pulmonary perfusion imaging in the current literature and discuss its advantages,limitations and future research scope. 展开更多
关键词 Pulmonary perfusion MRI Pulmonary hypertension Dynamic contrast enhanced magnetic resonance imaging Chronic thromboembolic pulmonary hypertension Computed tomography pulmonary angiography Chronic thromboembolic disease
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Use of endolumenal functional lumen imaging probe in investigating paediatric gastrointestinal motility disorders
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作者 Emily White Mohamed Mutalib 《World Journal of Clinical Pediatrics》 2023年第4期162-170,共9页
Investigating gastrointestinal(GI)motility disorders relies on diagnostic tools to assess muscular contractions,peristalsis propagation and the integrity and coordination of various sphincters.Manometries are the gold... Investigating gastrointestinal(GI)motility disorders relies on diagnostic tools to assess muscular contractions,peristalsis propagation and the integrity and coordination of various sphincters.Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis.Endolumenal functional lumen imaging probe(EndoFLIP)an emerging technology,uses impedance planimetry to measure hollow organs cross sectional area,distensibility and compliance.It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters,oesophageal body,the pylorus and the anal canal.In this article,we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice.The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing.EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults. 展开更多
关键词 Endolumenal functional lumen imaging probe PAEDIATRIC Gastrointestinal motility
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A Simple Model Unifies Space, Matter and Light
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作者 Guoliang Fu Tony Yang Fu 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1098-1133,共36页
An alternative model is proposed to derive several of Einstein’s basic relativity equations, which would make relativity theory easier to comprehend and more intuitive. Despite the radical nature of the hypothesis, t... An alternative model is proposed to derive several of Einstein’s basic relativity equations, which would make relativity theory easier to comprehend and more intuitive. Despite the radical nature of the hypothesis, the findings are consistent with many predictions of relativity theory and shed light on the fundamental aspects of various relativity concepts. The model unifies Space, Matter, and Light, all of which are of the same nature. The building block is a mass-unit composed of size and motion. The invariant space-time interval and the corresponding space-mass interval are derived and explained. Only when there is “external force”, the Einstein’s energy-momentum equation becomes applicable. The “no external force” scenario leads to the generation of a new energy-momentum equation that explains the nature of gravity and perhaps even dark matter. Modified Minkowski space-time and space-mass diagrams clearly depict time dilation, length contraction, the mass-momentum-energy relationship, and other relativity phenomena. 展开更多
关键词 RELATIVITY Time Dilation Length Contraction GRAVITY Black Hole Dark Matter
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