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The Persistence and Zonal Scale of Atmospheric Dipolar Modes
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作者 Jie SONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期478-492,共15页
This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model sh... This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics. 展开更多
关键词 NAM NAO eddy feedback persistENCE linear term
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THE PERSISTENCE OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING
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作者 赵敏 袁荣 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1096-1114,共19页
In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or ext... In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or extinction of the prey and of the predator separately in various moving frames.In particular,they achieved a complete picture in the local diffusion case.However,the question of the persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.'s paper.By using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et al.to achieve a complete picture in the nonlocal diffusion case. 展开更多
关键词 predator-prey system persistENCE nonlocal dispersal shifting environment
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Characteristics and Mechanisms of Persistent Wet–Cold Events with Different Cold-air Paths in South China
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作者 Xiaojuan SUN Li CHEN +1 位作者 Chuhan LU Panxing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1171-1183,共13页
We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part o... We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part of South China is higher than that in the eastern part.The pattern of single-station frequency of the PWCEs are“Yangtze River(YR)uniform”and“east–west inverse”.The YR uniform pattern is the dominant mode,so we focus on this pattern.The cold-air paths for PWCEs of the YR uniform pattern are divided into three types—namely,the west,northwest and north types—among which the west type accounts for the largest proportion.The differences in atmospheric circulation of the PWCEs under the three types of paths are obvious.The thermal inversion layer in the lower troposphere is favorable for precipitation during the PWCEs.The positive water vapor budget for the three types of PWCEs mainly appears at the southern boundary. 展开更多
关键词 persistent wet–cold events cold-air paths circulation characteristics water vapor
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Hydromassage of macular hole edges for large and persistent full-thickness macular holes
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作者 Yi Cai Wen-Bo Liu +5 位作者 Duo Wei Xun Deng Xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-Hong Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期551-557,共7页
●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consec... ●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with MH.Inclusion criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous vitrectomy.Standard MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 closure.No significant differences were observed in the preoperative OCT variables between the two closure types.Eyes with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent MH.This technique may serve as an effective adjunctive maneuver during challenging MH surgery. 展开更多
关键词 macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage
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The Transport and Persistence of Escherichia coli in Leachate from Poultry Litter Amended Soils
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作者 Lorra Belle Hill 《Open Journal of Soil Science》 2024年第4期269-282,共14页
Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay s... Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay soil and Hartsells Sandy soil was conducted using soil columns and simulated groundwater leaching. Enumeration of initial E. coli was determined to range from 2.851 × 10<sup>3</sup> to 3.044 × 10<sup>3</sup> CFU per gram of soil. These results have been used in a batch study to determine the persistence rate of E. coli in Decatur silty Clay soil and Hartsells Sandy soil. Results prove that E. coli survival growth rate increases for clay soil later than and at a higher rate than sandy soil. The column study has determined that E. coli was transported at a rate of 3.7 × 10<sup>6</sup><sup> </sup>CFU for Decatur silty loam and 6.3 × 10<sup>6</sup><sup> </sup>CFU for Hartsells sandy per gram of soil. Further, linear regression analysis predictions show higher porosity and soil moisture content affect transport, and Hartsells sandy soil has higher transport of E. coli due to its higher porosity and lower volumetric water content. 展开更多
关键词 TRANSPORT LEACHATE persistENCE Poultry Litter E. coli
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The Roles of Low-level Jets in “21·7” Henan Extremely Persistent Heavy Rainfall Event 被引量:6
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作者 Yuhan LUO Yu DU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第3期350-373,共24页
An extremely heavy rainfall event lasting from 17 to 22 July 2021 occurred in Henan Province of China, with accumulated precipitation of more than 1000 mm over a 6-day period that exceeded its mean annual precipitatio... An extremely heavy rainfall event lasting from 17 to 22 July 2021 occurred in Henan Province of China, with accumulated precipitation of more than 1000 mm over a 6-day period that exceeded its mean annual precipitation. The present study examines the roles of persistent low-level jets(LLJs) in maintaining the precipitation using surface station observations and reanalysis datasets. The LLJs triggered strong ascending motions and carried moisture mainly from the outflow of Typhoon In-fa(2021). The varying directions of the LLJs well corresponded to the meridional shifts of the rainfall. The precipitation rate reached a maximum during 20-21 July as the LLJs strengthened and expanded vertically into double LLJs, including synoptic-weather-system-related LLJs(SLLJs) at 850–700 hPa and boundary-layer jets(BLJs)at ~950 hPa. The coupling of the SLLJ and BLJ provided strong mid-and low-level convergence on 20 July, whereas the SLLJ produced mid-level divergence at its entrance that coupled with low-level convergence at the terminus of the BLJ on21 July. The formation mechanisms of the two types of LLJs are further examined. The SLLJs and the low-pressure vortex(or inverted trough) varied synchronously as a whole and were affected by the southwestward movement of the WPSH in the rainiest period. The persistent large total pressure gradient force at low levels also maintained the strength of low-level geostrophic winds, thus sustaining the BLJs on the synoptic scale. The results based on a Du-Rotunno 1D model show that the Blackadar and Holton mechanisms jointly governed the BLJ dynamics on the diurnal scale. 展开更多
关键词 extremely persistent heavy rainfall low-level jet dynamic and thermodynamic effect diurnal cycle
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Assimilation of the FY-4A AGRI Clear-Sky Radiance Data in a Regional Numerical Model and Its Impact on the Forecast of the“21·7”Henan Extremely Persistent Heavy Rainfall 被引量:3
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作者 Lan XU Wei CHENG +5 位作者 Zhongren DENG Juanjuan LIU Bin WANG Bin LU Shudong WANG Li DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期920-936,共17页
Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional ob... Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is performed.The forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional observations for the“21·7”Henan extremely heavy rainfall is analyzed and compared with a baseline test that assimilates only conventional observations in this study.The results show that the 24-h cumulative precipitation forecast by the assimilation experiment with the addition of the AGRI exceeds 500 mm,compared to a maximum value of 532.6 mm measured by the national meteorological stations,and that the location of the maximum precipitation is consistent with the observations.The results for the short periods of intense precipitation processes are that the simulation of the location and intensity of the 3-h cumulative precipitation is also relatively accurate.The analysis increment shows that the main difference between the two sets of assimilation experiments is over the ocean due to the additional ocean observations provided by FY-4A,which compensates for the lack of ocean observations.The assimilation of satellite data adjusts the vertical and horizontal wind fields over the ocean by adjusting the atmospheric temperature and humidity,which ultimately results in a narrower and stronger WV transport path to the center of heavy precipitation in Zhengzhou in the lower troposphere.Conversely,the WV convergence and upward motion in the control experiment are more dispersed;therefore,the precipitation centers are also correspondingly more dispersed. 展开更多
关键词 FY-4A AGRI clear-sky radiance satellite data assimilation “21·7”Henan extremely persistent heavy rainfall
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Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals 被引量:1
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作者 Yuhan Zhu Jia Wei Jun Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期97-103,共7页
Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced i... Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced in the preparation process of biochar, playing an important role in the removal of pollutants.In this study, sludge-derived biochars(SBC_(120) and SBC_(270)) were prepared by the hydrothermal carbonization under two temperatures(120℃ and 270℃) to investigate their removal abilities of Cr(Ⅵ). The maximum removal amounts of Cr(Ⅵ) by SBC_(120) and SBC_(270) were 16.58 and 22.93 mg·g^(-1), respectively. It was further revealed that the appearance of Cr(Ⅲ), as a result of EPFRs on sludge-derived biochar(SBC) transferred electrons to Cr(Ⅵ) in neutral solutions. That is to say, oxygen-centered(O-centered) EPFRs on SBC_(120) and carbon-centered(C-centered) EPFRs on SBC_(270) all could be used as electron donors to Cr(Ⅵ) to make it become Cr(Ⅲ). This study not only provides a theoretical basis for the mechanism of pollutants removal by sludge-derived biochar but also offers a new perspective on the direct effect of EPFRs on pollutants. 展开更多
关键词 Sludge-derived biochar Environmentally persistent free radicals Chromium Removal Reduction
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Development and Validation of a Postoperative Prognostic Nomogram to Predict Recurrence in Patients with Persistent Atrial Fibrillation:A Retrospective Cohort Study 被引量:1
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作者 Cong-Ying Deng Ai-Lin Zou +1 位作者 Ling Sun Yuan Ji 《Cardiovascular Innovations and Applications》 2023年第1期32-43,共12页
Background:Patients with persistent atrial fibrillation(PsAF)have a high risk of recurrence after catheter radiofre-quency ablation.Nevertheless,no effective prognostic tools have been developed to identify these high... Background:Patients with persistent atrial fibrillation(PsAF)have a high risk of recurrence after catheter radiofre-quency ablation.Nevertheless,no effective prognostic tools have been developed to identify these high-risk patients to date.This study sought to develop and validate a simple linear predictive model for predicting postoperative recurrence in patients with PsAF.Methods:From June 2013 to June 2021,patients with PsAF admitted to our hospital were enrolled in this single-center,retrospective,observational study.The characteristics substantially associated with recurrence in patients with PsAF were screened through univariate and multivariate logistic regression analysis.The receiver operating charac-teristic curve was used to assess the predictive significance of the nomogram model after nomogram development.Furthermore,to assess the clinical value of the nomogram,we performed calibration curve and decision curve analyses.Results:A total of 209 patients were included in the study,42(20.10%)of whom were monitored up to 1 year for recurrent AF.The duration of AF episodes,left atrial diameter,BMI,CKMB,and alcohol consumption were found to be independent risk factors(P<0.05)and were integrated into the nomogram model development.The area under the curve was 0.895,the sensitivity was 93.3%,and the specificity was 71.4%,thus indicating the model’s excellent predic-tive ability.The C-index of the predictive nomogram model was 0.906.Calibration curve and decision curve analyses further revealed that the model had robust prediction and strong discrimination ability.Conclusion:This simple,practical,and innovative nomogram can help clinicians in evaluation of the risk of PsAF recurrence after catheter ablation,thus facilitating preoperative evaluation,postoperative monitoring and ultimately the construction of more personalized therapeutic protocols. 展开更多
关键词 persistent atrial fibrillation NOMOGRAM RECURRENCE Prediction model
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Combined aqueous misdirection and persistent choroidal effusions following implantation of a Preserflo Micro Shunt
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作者 Huzaifa Malick Craig Wilde Richard E Stead 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期652-655,共4页
AIM:To describe a case of aqueous misdirection complicated by subsequent persistent choroidal effusions following implantation of a Preserflo Micro Shunt(PMS)device to treat advanced closed angle glaucoma.METHODS:A 67... AIM:To describe a case of aqueous misdirection complicated by subsequent persistent choroidal effusions following implantation of a Preserflo Micro Shunt(PMS)device to treat advanced closed angle glaucoma.METHODS:A 67-year-old caucasian female with advanced primar y angle-closure glaucoma on four medications with an intraocular pressure(IOP)of 26 mm Hg was listed for a PMS insertion with mitomycin C(MMC).RESULTS:Past ocular history was significant for pseudophakia and previous yttrium aluminum garnet(YAG)peripheral iridotomy.Surgery was uneventful but on the first postoperative day,she developed aqueous misdirection complicated by subsequent development of persistent uveal effusions.Conventional treatment strategies including atropine drops,YAG hyaloidotomy and choroidal effusion drainage proved ineffective.A combination of oral steroids and pars plana vitrectomy(PPV)along with an irido-zonulohyloidectomy(IZH)proved efficacious.CONCLUSION:To the best of the author’s knowledge,this is the first published case of aqueous misdirection complicated with the presence of significant,unresolving choroidal effusions,highlighting the possibility and sequelae of comorbid pathology in nanophthalmic eyes. 展开更多
关键词 COMBINED AQUEOUS misdirections persistENT choroidal EFFUSIONS
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Clinicopathological and oncological significance of persistent prostate-specific antigen after radical prostatectomy:A systematic review and meta-analysis
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作者 Shulin Wu Sharron X.Lin +4 位作者 Kristine M.Cornejo Rory K.Crotty Michael L.Blute Douglas M.Dahl Chin-Lee Wu 《Asian Journal of Urology》 CSCD 2023年第3期317-328,共12页
Objective:To investigate the association of persistently elevated prostate-specific antigen(PSA)after radical prostatectomy(RP)with clinicopathological features and long-term oncological prognosis for the development ... Objective:To investigate the association of persistently elevated prostate-specific antigen(PSA)after radical prostatectomy(RP)with clinicopathological features and long-term oncological prognosis for the development of a potential management strategy.Methods:A systematic literature search was performed using PubMed and Web of Science up to June 2021 to identify the eligible studies focusing on understanding the impact of persistent PSA in patients who underwent RP for localized prostate cancer.Meta-analyses were performed on parameters with available information.Results:A total of 32 RP studies were identified,of which 11 included 26719 patients with consecutive cohorts and the remaining 21 comprised 24177 patients with cohorts carrying specific restrictions.Of the 11 studies with consecutive cohorts,the incidence of persistent PSA varied between 3.1%and 34.6%with a median of 11.0%.Meta-analyses revealed patients with persistent PSA consistently showed unfavorable clinicopathological features and a more than 3.5-fold risk of poorer biochemical recurrence,metastasis,and prostate cancer-specific mortality prognosis independently,when compared to patients with undetectable PSA.Similarly,cases with persistent PSA in different specific patient cohorts with a higher risk of prostate cancer also showed a trend of worse outcomes.Conclusion:We found that the frequency of persistent PSA was about 11.0%in consecutive RP cohorts.Persistent PSA was significantly associated with unfavorable clinicopathological characteristics and worse oncological outcomes.Patients with persistent PSA after RP may benefit from early salvage treatment to delay or prevent biochemical recurrence,improving oncological outcomes for these patients.Further prospective randomized controlled trials are warranted to understand optimal systemic therapy in these patients. 展开更多
关键词 Prostate cancer Radical prostatectomy persistent prostatespecific antigen Prognosis SALVAGE Systematic review META-ANALYSIS
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Optimization of communication topology for persistent formation in case of communication faults
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作者 王国强 罗贺 +1 位作者 胡笑旋 台建玮 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期610-624,共15页
To address the optimization problem of communication topology for persistent formation in the case of communication faults such as link interruption,transmitter failure,and receiver failure a two-stage model including... To address the optimization problem of communication topology for persistent formation in the case of communication faults such as link interruption,transmitter failure,and receiver failure a two-stage model including fast reconstruction of communication topology and re-optimization of communication topology is constructed.Then,a fast reconstruction algorithm of communication topology for persistent formation(FRA-CT-PF),based on optimally rigid graph,arc addition operation,and path reversal operation,is proposed,which can quickly generate a feasible reconstructed communication topology after communication faults,thus ensuring the safety of the agents and maintaining the formation shape of persistent formation.Furthermore,a re-optimization algorithm of communication topology for persistent formation(ROA-CTPF),based on agent position exchange,is proposed,which can further obtain a reoptimized communication topology to minimize the formation communication cost while still maintaining the formation shape of persistent formation.The time complexities of these two algorithms are also analyzed.Finally,the effectiveness of the above algorithms is verified by numerical experiments.Compared with existing algorithms,FRA-CT-PF can always obtain feasible reconstructed communication topology in much less time under all communication fault scenarios,and ROA-CT-PF can obtain a reoptimized communication topology to further reduce the formation communication cost in a shorter time. 展开更多
关键词 persistent formation communication topology formation communication cost communication fault
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Application of immersion B-scan ultrasonography in diagnosis of complex retinal detachment,persistent hyperplastic primary vitreous and intraocular tumors
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作者 Qing-Hua Yang An-Qi Liu +5 位作者 Ying-Xin Qu Hong-Tao Zhang Bing Chen Yan Li Liang Jia Li-Qiang Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期388-395,共8页
AIM:To evaluate the diagnostic value of panoramic immersion B-scan ultrasonography(Pano-immersion B-scan,PIB)in complex retinal detachment(RD),persistent hyperplastic primary vitreous(PHPV)and intraocular tumors.METHO... AIM:To evaluate the diagnostic value of panoramic immersion B-scan ultrasonography(Pano-immersion B-scan,PIB)in complex retinal detachment(RD),persistent hyperplastic primary vitreous(PHPV)and intraocular tumors.METHODS:The clinical data of 44 patients collected from May 2012 to December 2019 in Chinese PLA General Hospital was retrospectively studied.All of these patients underwent PIB of the eye,because it was difficult to diagnose by routine ocular fundus examination,conventional ultrasound or/and ultrasonic biomicroscope(UBM)due to opacity of refractive media,pupillary occlusion,large involvement or special location of the lesion.The imaging features of difficult cases in PIB were analyzed.The diagnosis accuracy rating of PIB were evaluated and contrasted with conventional ultrasound or UBM by the standard of intraoperative diagnosis or/and pathological results.RESULTS:According to intraoperative diagnosis or pathological results as gold standard,among the 44 cases,there were 19 cases missed diagnosis,misdiagnosed or difficult-to-diagnose by conventional ultrasound or UBM,including 4 cases of long-standing RD difficult to diagnose,4 cases misdiagnosed,and 11 cases incompletely observed or miss diagnosed.The diagnostic accuracy rate of PIB and conventional ultrasound or UBM were 100%(44/44)and 56.82%(25/44),and the sensitivity of them were 100%and 56.82%.All the patients underwent PIB and were diagnosed as RD(15 cases),retinal and choroidal detachment(4 cases),subchoroidal hematocele(1 case),vitreous opacity and/or organic membrane formation(4 cases),PHPV(12 cases),iris and/or ciliary body tumors(3 cases),and choroidal tumors(6 cases).According to the intraoperative diagnosis or pathological results,the diagnostic coincidence rate of PIB was 100%,which was significantly higher than conventional ultrasound and UBM.CONCLUSION:PIB can help to accurately diagnose complex RD,PHPV,and intraocular masses with special location or/and excessive size.It has important diagnostic value for patients with equivocal findings at conventional ultrasound examination. 展开更多
关键词 IMMERSION ULTRASONOGRAPHY PANORAMIC retinal detachment persistent hyperplastic primary vitreous intraocular tumor
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Update on the current management of persistent and recurrent primary hyperparathyroidism after parathyroidectomy
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作者 Efstathios T Pavlidis Theodoros E Pavlidis 《World Journal of Clinical Cases》 SCIE 2023年第10期2213-2225,共13页
Primary hyperparathyroidism(pHPT)is the third most common endocrine disease.The surgical procedure aims for permanent cure,but recurrence has been reported in 4%-10%of pHPT patients.Preoperative localization imaging i... Primary hyperparathyroidism(pHPT)is the third most common endocrine disease.The surgical procedure aims for permanent cure,but recurrence has been reported in 4%-10%of pHPT patients.Preoperative localization imaging is highly valuable.It includes ultrasound,computed tomography(CT),single-photonemission CT,sestamibi scintigraphy and magnetic resonance imaging.The operation has been defined as successful when postoperative continuous eucalcemia exists for more than the first six months.Ongoing hypercalcemia during this period is defined as persistence,and recurrence is defined as hypercalcemia after six months of normocalcemia.Vitamin D is a crucial factor for a good outcome.Intraoperative parathyroid hormone(PTH)monitoring can safely predict the outcomes and should be suggested.PTH≤40 pg/mL or the traditional decrease≥50%from baseline minimizes the likelihood of persistence.Risk factors for persistence are hyperplasia and normal parathyroid tissue on histopathology.Risk factors for recurrence are cardiac history,obesity,endoscopic approach and low-volume center(at least 31 cases/year).Cases with double adenomas or four-gland hyperplasia have a greater likelihood of persistence/recurrence.A 6-mo calcium>9.7 mg/dL and eucalcemic parathyroid hormone elevation at 6 mo may be associated with recurrence necessitating long-term follow-up.18F-fluorocholine positron emission tomography and 4-dimensional CT in persistent and recurrent cases can be valuable before reoperation.With these novel advances in preoperative imaging and localization as well as intraoperative PTH measurement,the recurrence rate has dropped to 2.5%-5%.Sixmonth serum calcium≥9.8 mg/dL and parathyroid hormone≥80 pg/mL indicate a risk of recurrence.Negative sestamibi scintigraphy,diabetes and elevated osteocalcin levels are predictors of multiglandular disease,which brings an increased risk of persistence and recurrence.Bilateral neck exploration was considered the gold-standard diagnostic method.Minimally invasive parathyroidectomy and neck exploration are both effective surgical techniques.Multidisciplinary diagnostic and surgical management is required to prevent persistence and recurrence.Long-term follow-up,even up to 10 years,is necessary. 展开更多
关键词 Parathyroid hormone Minimally invasive parathyreoidectomy HYPERPARATHYROIDISM Primary REOPERATION persistENT Recurrent hypercalcemia
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An Effective Threat Detection Framework for Advanced Persistent Cyberattacks
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作者 So-Eun Jeon Sun-Jin Lee +5 位作者 Eun-Young Lee Yeon-Ji Lee Jung-Hwa Ryu Jung-Hyun Moon Sun-Min Yi Il-Gu Lee 《Computers, Materials & Continua》 SCIE EI 2023年第5期4231-4253,共23页
Recently,with the normalization of non-face-to-face online environments in response to the COVID-19 pandemic,the possibility of cyberattacks through endpoints has increased.Numerous endpoint devices are managed meticu... Recently,with the normalization of non-face-to-face online environments in response to the COVID-19 pandemic,the possibility of cyberattacks through endpoints has increased.Numerous endpoint devices are managed meticulously to prevent cyberattacks and ensure timely responses to potential security threats.In particular,because telecommuting,telemedicine,and teleeducation are implemented in uncontrolled environments,attackers typically target vulnerable endpoints to acquire administrator rights or steal authentication information,and reports of endpoint attacks have been increasing considerably.Advanced persistent threats(APTs)using various novel variant malicious codes are a form of a sophisticated attack.However,conventional commercial antivirus and anti-malware systems that use signature-based attack detectionmethods cannot satisfactorily respond to such attacks.In this paper,we propose a method that expands the detection coverage inAPT attack environments.In this model,an open-source threat detector and log collector are used synergistically to improve threat detection performance.Extending the scope of attack log collection through interworking between highly accessible open-source tools can efficiently increase the detection coverage of tactics and techniques used to deal with APT attacks,as defined by MITRE Adversarial Tactics,Techniques,and Common Knowledge(ATT&CK).We implemented an attack environment using an APT attack scenario emulator called Carbanak and analyzed the detection coverage of Google Rapid Response(GRR),an open-source threat detection tool,and Graylog,an open-source log collector.The proposed method expanded the detection coverage against MITRE ATT&CK by approximately 11%compared with that conventional methods. 展开更多
关键词 Advanced persistent threat CYBERSECURITY endpoint security MITRE ATT&CK open-source threat detector threat log collector
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Solitary acral persistent papular mucinosis nodule:A case report and summary of eight Korean cases
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作者 Yu Jeong Park Hui Young Shin +3 位作者 Woo Kyoung Choi Ai-Young Lee Seung Ho Lee Jong Soo Hong 《World Journal of Clinical Cases》 SCIE 2023年第13期3086-3091,共6页
BACKGROUND Acral persistent papular mucinosis(APPM)is a rare idiopathic subtype of localized lichen myxedematosus.To date,there have been 40 APPM cases reported worldwide;however,only 7 cases have been reported in the... BACKGROUND Acral persistent papular mucinosis(APPM)is a rare idiopathic subtype of localized lichen myxedematosus.To date,there have been 40 APPM cases reported worldwide;however,only 7 cases have been reported in the Korean literature.CASE SUMMARY A 70-year-old man was referred to our hospital with a solitary pinkish nodule on the dorsum of his right hand.Despite the absence of symptoms,the patient wanted to know the exact diagnosis;thus,a biopsy was performed.Histopathological examination of a biopsy specimen obtained from the nodule on the dorsum of his hand revealed orthokeratotic hyperkeratosis with patchy parakeratosis,prominent hypergranulosis,and diffuse dissecting mucinous deposition between collagen bundles,along with some bland-looking spindle cells throughout the dermis.The nodule was histologically diagnosed as an APPM,and an intralesional triamcinolone injection(2.5 mg/mL)was started every 2 wk.After three sessions of treatment,the patient showed marked improvements.CONCLUSION To the best of our knowledge,this is the first case of a Korean APPM presenting as a solitary nodule that showed a marked response to triamcinolone intralesional injection.Since it is a rare disease,we report this case to contribute to future research on the pathogenesis and treatment of APPM. 展开更多
关键词 Acral persistent papular mucinosis Localized lichen myxedematosus Cutaneous mucinosis Mucin Case report
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Advanced Persistent Threat Detection and Mitigation Using Machine Learning Model
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作者 U.Sakthivelu C.N.S.Vinoth Kumar 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3691-3707,共17页
The detection of cyber threats has recently been a crucial research domain as the internet and data drive people’s livelihood.Several cyber-attacks lead to the compromise of data security.The proposed system offers c... The detection of cyber threats has recently been a crucial research domain as the internet and data drive people’s livelihood.Several cyber-attacks lead to the compromise of data security.The proposed system offers complete data protection from Advanced Persistent Threat(APT)attacks with attack detection and defence mechanisms.The modified lateral movement detection algorithm detects the APT attacks,while the defence is achieved by the Dynamic Deception system that makes use of the belief update algorithm.Before termination,every cyber-attack undergoes multiple stages,with the most prominent stage being Lateral Movement(LM).The LM uses a Remote Desktop protocol(RDP)technique to authenticate the unauthorised host leaving footprints on the network and host logs.An anomaly-based approach leveraging the RDP event logs on Windows is used for detecting the evidence of LM.After extracting various feature sets from the logs,the RDP sessions are classified using machine-learning techniques with high recall and precision.It is found that the AdaBoost classifier offers better accuracy,precision,F1 score and recall recording 99.9%,99.9%,0.99 and 0.98%.Further,a dynamic deception process is used as a defence mechanism to mitigateAPTattacks.A hybrid encryption communication,dynamic(Internet Protocol)IP address generation,timing selection and policy allocation are established based on mathematical models.A belief update algorithm controls the defender’s action.The performance of the proposed system is compared with the state-of-the-art models. 展开更多
关键词 Advanced persistent threats lateral movement detection dynamic deception remote desktop protocol Internet Protocol attack detection
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Integrated analysis of comorbidity, pregnant outcomes, and amniotic fluid cytogenetics of fetuses with persistent left superior vena cava
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作者 Xin Yang Xin-Hui Su +4 位作者 Zhen Zeng Yao Fan Yuan Wu Li-Li Guo Xiao-Yan Xu 《World Journal of Cardiology》 2023年第10期500-507,共8页
BACKGROUND Persistent left superior vena cava(PLSVC)is the most common venous system variant.The clinical characteristics and amniotic fluid cytogenetics of fetuses with PLSVC remain to be further explored.AIM To deve... BACKGROUND Persistent left superior vena cava(PLSVC)is the most common venous system variant.The clinical characteristics and amniotic fluid cytogenetics of fetuses with PLSVC remain to be further explored.AIM To develop reliable prenatal diagnostic recommendations through integrated analysis of the clinical characteristics of fetuses with PLSVC.METHODS Cases of PLSVC diagnosed using prenatal ultrasonography between September 2019 and November 2022 were retrospectively studied.The clinical characteristics of the pregnant women,ultrasonic imaging information,gestational age at diagnosis,pregnancy outcomes,and amniocentesis results were summarized and analyzed using categorical statistics and the chi-square test or Fisher’s exact test.RESULTS Of the 97 cases diagnosed by prenatal ultrasound,49(50.5%)had isolated PLSVC and 48(49.5%)had other structural abnormalities.The differences in pregnancy outcomes and amniocentesis conditions between the two groups were statistically significant(P<0.05).No significant differences were identified between the two groups in terms of advanced maternal age and gestational age(P>0.05).According to the results of the classification statistics,the most common intrac-ardiac abnormality was a ventricular septal defect and the most common extrac-ardiac abnormality was a single umbilical artery.In the subgroup analysis,the concurrent combination of intra-and extracardiac structural abnormalities was a risk factor for adverse pregnancy outcomes(odds ratio>1,P<0.05).Additional-ly,all abnormal cytogenetic findings on amniocentesis were observed in the comorbidity group.One case was diagnosed with 21-trisomy and six cases was diagnosed with chromosome segment duplication.CONCLUSION Examination for other structural abnormalities is strongly recommended when PLSVC is diagnosed.Poorer pregnancy outcomes and increased amniocentesis were observed in PLSVC cases with other structural abnor-malities.Amniotic fluid cytogenetics of fetuses is recommended for PLSVC with other structural abnormalities. 展开更多
关键词 persistent left superior vena cava Prenatal diagnosis Amniotic fluid cytogenetics Pregnancy outcome Integrated analysis COMORBIDITY
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Persistent left superior vena cava in right hemiarch replacement under deep hypothermic circulatory arrest:A case report
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作者 Ze-Yu Mi Gang He +1 位作者 Hong-Li Gao Chao Li 《World Journal of Clinical Cases》 SCIE 2023年第32期7858-7864,共7页
BACKGROUND Persistent left superior vena cava(PLSVC),a relatively rare thoracic vascular malformation,can inconvenience perfusionists and operators when encountered during deep hypothermic circulatory arrest(DHCA).CAS... BACKGROUND Persistent left superior vena cava(PLSVC),a relatively rare thoracic vascular malformation,can inconvenience perfusionists and operators when encountered during deep hypothermic circulatory arrest(DHCA).CASE SUMMARY Herein,we describe the case of a patient with concurrent giant aortic arch aneurysm,aortic stenosis,and PLSVC.To treat these conditions,we performed right hemiarch and aortic valve replacements under DHCA.Notably,we applied“bilateral superior vena cava retrograde cerebral perfusion(RCP)”for cerebral protection,which significantly optimized the surgical procedure and reduced the risk of postoperative complications.The patient was discharged 14 d after surgery with no complications.CONCLUSION Surgical intervention for PLSVC under DHCA can be performed using the bilateral superior vena cava RCP approach. 展开更多
关键词 persistent left superior vena cava Aortic arch aneurysm Hemiarch replacement Deep hypothermic circulatory arrest Retrograde cerebral perfusion Case report
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Acute and Persistent Post-Craniotomy Pain: A Prospective 6-Month Follow-Up Questionnaire Study
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作者 Pasi Lahtinen Ville Koskela +4 位作者 Pawel Florkiewicz Juha E. Jääskeläinen Timo Koponen Jari Halonen Tadeusz Musialowicz 《Open Journal of Anesthesiology》 2023年第6期119-133,共15页
Introduction: The incidence of acute pain after craniotomy differs remarkably in previous studies, and the prevalence of persistent pain is not precisely known. We conducted 6-month follow-up surveys on the incidence ... Introduction: The incidence of acute pain after craniotomy differs remarkably in previous studies, and the prevalence of persistent pain is not precisely known. We conducted 6-month follow-up surveys on the incidence and intensity of acute and persistent pain after elective craniotomy. Methods: We carried out a prospective cohort study via a series of structured questionnaires to record acute pain intensity preoperatively and postoperatively, and the incidence of persistent pain 3 and 6 months after a craniotomy in a tertiary care center. Patients scheduled for elective craniotomy were interviewed the day before surgery, postoperatively before discharge from the hospital, and 3 and 6 months after surgery. Pain was assessed on a numeric rating scale (0 - 10) at rest and movement, as well as expectations of pain before surgery, efficacy of pain therapy, and satisfaction with pain treatment. The incidence of adverse events, sleep time and interruptions caused by pain, different pain types, and drugs used for pain treatment were also recorded. Results: A total of 152 patients were enrolled in the study and completed the preoperative questionnaire;123 (81%) completed postoperative questionnaire and 108 (72%) completed the 3- and 6-month follow-ups. The average pain score at the time of the postoperative questionnaire was moderate, 4 at rest and 5 upon movement. The percentage of patients experiencing mild pain at rest and upon movement was 52% and 49%, and moderate pain was 15% and 16%, respectively. Severe postoperative pain was detected in 5% and 8% of patients at rest and upon movement, respectively. Three months after surgery, 6% of patients reported mild pain at rest, 3% moderate pain at rest, and 1% severe pain at rest. Persistent mild and moderate pain at rest after 6 months was reported by 3% and 1% of patients, respectively. The most common adverse events were postoperative nausea and vomiting (11%) and abdominal discomfort (8%). During postoperative pain treatment in the intensive care unit or post-anesthesia care unit, 92% of patients received acetaminophen, 88% fentanyl, and 24% oxycodone. During neurosurgical ward care, ibuprofen was used in 61% of patients. Satisfaction with analgesia was high throughout the study period with a median satisfaction score of 9 postoperatively and 10 at 3 and 6 months on the 0 - 10 scale. Conclusion: The findings indicate that most patients experience moderate or mild pain after craniotomy, but patient satisfaction with pain treatment is high. Persistent pain after 3 and 6 months is rare and mild in nature. 展开更多
关键词 CRANIOTOMY Acute Pain persistent Pain Pain Treatment Adverse Events NEUROSURGERY
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