简介:AbstractBackground:In recent years, visual quality has been extensively investigated in various conditions. In this community-based population study, we analyzed the effects of aging, refraction, and Lens Opacification Classification System III (LOCSIII) score on retinal imaging quality in healthy Chinese adults.Methods:This cross-sectional study was conducted on sub-group subjects from The Handan Eye Study between October 2012 and January 2013. Healthy subjects over 30-years-old with logarithm of the minimal angle of resolution (logMAR) best-corrected visual acuity (BCVA) less than 0 were included. Retinal image quality was measured by optical quality analysis system (OQAS) and recorded as modulation transfer function cutoff frequency (MTFcutoff), OQAS value (OV) 100%, OV20%, OV9%, Strehl ratio (SR), and objective scatter index (OSI). The correlation between age, spherical equivalent refraction (SE), LOCSIII score, and optical quality parameters were investigated by multivariate analysis.Results:Among 1108 verified subjects, 690 subjects (1380 eyes) met the inclusion criteria. Their age ranged from 30 to 76 years, SE ranged from -4.75 to 2.75 D. They were divided into five age groups (30-39, 40-49, 50-59, 60-69, and ≥70 years) for further analysis. After multivariate analysis by mixed-effect linear model, SR (t = -3.03, P = 0.002), OV20% (t = -2.39, P = 0.017), and OV9% (t = -3.16, P = 0.001) significantly decreased with the increasing age, whereas logMAR BCVA (t = 4.42, P < 0.001) and OSI (t = 4.46, P < 0.001) significantly increased with age. As SE increased, SR (t = 2.74, P = 0.01), OV20% (t = 2.31, P = 0.02), and OV9% (t = 2.79, P = 0.005) significantly elevated, and OSI (t = -3.38, P < 0.001) significantly decreased. With the increase in cortical opacity score, all optical quality parameters except for SR significantly decreased, including MTFcutoff (t = -2.78, P = 0.01), OV100% (t = -2.78, P = 0.005), OV20% (t = -2.60, P = 0.009), and OV9% (t = -2.05, P = 0.04). As posterior sub capsular opacity score increased, MTFcutoff (t = -2.40, P = 0.02) and OV100% (t = -2.40, P = 0.01) significantly decreased, while OSI (t = 7.56, P < 0.001) significantly increased.Conclusions:In healthy Chinese adult population, optical quality-related parameters significantly decrease with the increasing age, and OSI significantly increases with age. In normal BCVA subjects, optical quality is significantly impacted by cortical and posterior sub capsular opacity rather than by nuclear opacity.
简介:Wetlandsoilqualitydegradationcausedbylarge-scaleagriculturalreclamationontheSanjiangPlainofNortheastChinahasbeenwidelyreported.Arelativesoilqualityevaluation(RSQE)modelandaprojectionpursuitevaluation(PPE)modelbasedonreal-codedacceleratinggeneticalgorithmwereintroducedtoevaluatequalityvariationsintoplayersofthemainwetlandsoilsontheSanjiangPlainin1999and2003,respectively.Assoilqualitydegradationboundarieswerevague,thisstudyestablishedtwofuzzysyntheticevaluation(FSE)modelsbasedontheoriginaldataandcriteriausedintheRSQEandPPEmodels.TheoutputsofthetwoFSEmodelswereobtainedbychoosingtwofuzzycompositeoperatorsM(∧,∨)andM(·,⊕).StatisticalanalysisshowedthattheresultsoftheFSE,RSQE,andPPEmodelswerecorrelated.Inparticular,outputsoftheFSEmodelusingM(·,⊕)weresignificantlycorrelatedwiththoseoftheRSQEmodelwithr=0.989atP<0.01.ComparedwithRSQEandPPEmodels,theFSEmodelmaybemoreobjectiveinshowingsoilqualityvariationsandwasclosertothenaturalsituation,showingthefeasibilityandapplicabilityoftheFSEmodelinevaluatingsoilqualitydegradation.However,thechoiceofcompositeoperatorwasofcriticalimportance.ThestudyofwetlandsoilqualitydegradationontheSanjiangPlainwasofscientificandpracticalsignificanceforprotectionandmanagementofsoilsandforsustainabledevelopmentofagricultureinthisareainthefuture.
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简介:Basedonalargeamountofdissectionatweldedinterfaceandquantitativemicroscopicexaminationofweldedrate,thesuitablelimitgreyscalevaluewasdetermined,andtheweldedrateofsuperplasticsolid-stateweldinginterfaceofheterogeneoussteelwassystematicallystudiedbymeansofself-madeultrasonicC-scanningimaginginspectionsystem.Theexperimentalresultsshow:theweldedstateofsuperplasticsolid-stateweldinginterfaceofheterogeneoussteelcanbeconductedtobemoreaccurately,reliablyandquicklyinspectedbymeansofthissystem,andtheultrasonictestingresultsaregoodconsistentwithactualexaminationresultsoftheinterfacedefectivedistribution.Withintheextentofthesuitbleweldedrate,theweldedratein40Cr/T10Asuperplasticweldingprocesstestedbythissystemislinearwithitstensilestrengthofjoint.
简介:Twoopposingintellectualtraditionsandtheircontem-porarydevelopmentsregardingtherelationsamongpopulation,availableresources,andqualityoflifeasreflectedineconomicgrowtharereviewed.Whatisatissueiswhetherpopulationgrowthisdetrimentaltoorbeneficialforeconomicdevelopment.Neitheroftheextremeviewsgivesacompletepictureoftheinterplayamongpopulation,resources,andqualityoflife.Followingpreviousliteratureonthetopic,thispaperestablishesamorebalancedapproachthatconsidersthefunctionlinkingpopulationandqualityoflifenotconstantbutvariableandregardsthelimitednessofresourcesasnotabsolutebutrelativetoregionsandsocieties.Theproposedapproachismoreflexibleinbetterexplainingtherelationbetweenpopulationandeconomicgrowth.Chinaisexaminedasacaseinpointtoshedlightontheinteractionofpopulationgrowth,economicdevelopment,andavailableresources,anditsrecentpost-economicreformexperiencesshowcasetheappropriatenessofthesyntheticapproach.
简介:DistributedBraggreflectors(DBRs)areessentialcomponentsforthedevelopmentofoptoelectronicdevices.Inthispaper,wefirstreporttheuseofthenanoporousGaN(NP-GaN)DBRasatemplateforregrowthofInGaN-basedlight-emittingdiodes(LEDs).Thewafer-scaleNP-GaNDBR,whichisfabricatedbyelectrochemicaletchinginaneutralsolution,hasasmoothsurface,highreflectivity(>99.5%),andwidespectralstopbandwidth(>70nm).ThechemicalcompositionoftheregrownLEDthinfilmissimilartothatofthereferenceLED,butthephotoluminescence(PL)lifetime,PLintensity,andelectroluminescenceintensityoftheLEDwiththeDBRareenhancedseveraltimescomparedtothoseofthereferenceLED.TheintensityenhancementisattributedtothelightreflectioneffectoftheNP-GaNDBRandimprovedcrystallinequalityasaresultoftheetchingscheme,whereastheenhancementofPLlifetimeisattributabletothelatter.
简介:Theutilizationofreclaimedwatercouldbeanefficienttooltoalleviatewaterscarcity,especiallyfordryriveraugmentation.However,itiscrucialtomonitorwaterqualitytoensuresafetytohumanhealthandtoavoidnegativeeffectsontheenvironment.ReclaimedwatersampleswerecollectedbimonthlyfromMaytoNovemberin2010inChaobaiRiver,andthephysiochemicalparametersweredetermined.Themainresultsareasfollows:Theparametersexceedingthethresholdvalueofthewaterguidelinesaremainlynutritionrelatedtonitrogenandphosphorus,whichareknowntoincreasetheriskofeutrophicationinsurfacewaters.Additionally,nitriteandnitratecanbedetrimentaltohumanhealth.ThemajorityoftheparametershaveapeakingconcentrationinMay,whereasotherseithershowsignificanttemporalvariationovertheentireperiodorremainrelativelyconstantinallfourmonths.Correlationanalysisshowsthatsomeparameters(pH,TandB)havenosignificantcorrelationwithothers,whereassignificantpositivecorrelationwasfoundforSrwithECandTDS,forCIwithTDS,forSi02withTPandforNO3-NwithTNandasignificantnegativecorrelationbetweenSO4andBa.Accordingtoprincipalcomponentanalysis,60.108%ofthetotaldataisrepresentedbydominantsolutes,andthesecondprincipalcomponentwithapercentageof31.876comprisesparametersrelatedtonitrogen.Subsequentclusteranalysisofparametersidentifiedfourgroups,whichrepresentdifferentcompositions,andsamplesinMaydifferfromothers.
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简介:TheLingtong-Jiaojiaore-centralizeddistrictiscontrolledbythetectonicstressfieldcharacterizedbYthecombinationofextensionandstrike-slip,andthedip,dipangle,pitchandpitchangleoftheorebodiesareallconstrainedbythedynamicconditionsofthetectonics.Themetallotectonicseriesfortheore-centralizeddistrictbelongtothetypeofacombinationofextensionandstrike-slipandcanbesubdividedintofoursub-series.Theore-formingprocessinthebrittleregimecanbedisintegratedintotwostages,i.e.,theembryonicfracturestageandthemegascopicfracturestage,andore-formingprocessisrathercommonintheore-centralizeddistrictattheformerstage.Moreover,severalkeystructuralpatternsandtheirfeatureswerediscussedandapreliminaryassessmentabouttheore-formingprospectinthisdistrictwasmadeinthepaper.
简介:为了在无线传感器网络(WSN)完成安全通讯,在有有限计算能力的传感器节点随机在敌对领土上被散布的地方,各种各样的关键分发前策划(KPS)被建议了。在这份报纸,新KPS在有限的地上基于symplectic几何学被建议。在一个symplectic空格的固定维的subspace代表一个节点,所有1-dimensionalsubspaces表示钥匙和每个节点分享了钥匙。但是这天真的印射不保证一个好网络得到跳回。因此,它被建议二个节点不得不计算一把pairwise钥匙的提高的KPS,仅当他们分享至少q普通钥匙。这条途径对节点俘获攻击提高跳回。与解决方案的存在相比,结果证明那条新途径更加提高网络可伸缩性,并且完成好连接和好全面性能。
简介:ThemetallogenictheoryofpolygeneticcompoundoredepositistheImportantbasisforlocationpredictionofhiddenoredepositsindiwaregions.Itcanplayanimportantroleineachstepofpredictionresearch,targetingprocedure,acquiringinformationandintegratinginformation.Inthispaper,theauthorsdiscusseshowtoconstructgeologicalconceptbyusingofthemetallogenictheoryofpolygeneticoredepositsforpredictingtargetingarea,toarrangeinvestigationanddetectionforgettingenoughusefulinformation,andtoanalyzeandintegrateinformationforreachingatrustfulpredictionconclusion.Accordingtothesestrategies,weconductasuccessfulpredictionoflocationofhiddenorebodiesintheouteroftheFenghuangshancoppermine,aprincipalproducingmineinTonglingCu-Audistrict.
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简介:AbstractBackground:Finding an optimal treatment strategy for adolescent idiopathic scoliosis (AIS) patients remains challenging because of its intrinsic complexity. For mild to moderate scoliosis patients with lower skeletal growth potential (Risser 3-5), most clinicians agree with observation treatment; however, the curve progression that occurs during puberty, the adolescent period, and even in adulthood, remains a challenging issue for clinicians. The aim of the study is to investigate the efficacy of Schroth exercise in AIS patients with lower skeletal growth potential (Risser 3-5) and moderate scoliosis (Cobb angle 20°-40°).Methods:From 2015 to 2017, data of 64 patients diagnosed with AIS in Peking University Third Hospital were reviewed. Forty-three patients underwent Schroth exercise were classified as Schroth group, and 21 patients underwent observation were classified as observation group. Outcomes were measured by health-related quality of life (HRQOL) and radiographic parameters. HRQOL was assessed using the visual analog scale (VAS) scores for back, Scoliosis Research Society-22 (SRS-22) patient questionnaire. Radiographic spinopelvic parameters were obtained from anteroposterior and lateral X-rays. The pre-treatment and post-treatment HRQOL and radiographic parameters were tested to validate Schroth exercise efficacy. The inter-rater reliability of the radiographic parameters was tested using the interclass correlation coefficient (ICC). The paired t test was used to examine HRQOL and radiographic parameters. Clinical relevance between C2-C7 sagittal vertical axis (SVA) and thoracic kyphosis was analyzed using Spearman correlation.Results:In Schroth group, VAS back score, SRS-22 pain, and SRS-22 self-image domain were significantly improved from pre-treatment 3.0 ± 0.8, 3.6 ± 0.5, and 3.5 ± 0.7 to post-treatment 1.6 ± 0.6 (t = 5.578, P = 0.013), 4.0 ± 0.3 (t = -3.918, P = 0.001), and 3.7 ± 0.4 (t = -6.468, P < 0.001), respectively. No significant improvements of SRS-22 function domain (t = -2.825, P = 0.088) and mental health domain (t = -3.174, P = 0.061) were observed. The mean Cobb angle decreased from 28.9 ± 5.5° to 26.3 ± 5.2° at the final follow-up, despite no statistical significance was observed (t = 1.853, P = 0.102). The mean C2-C7 SVA value decreased from 21.7 ± 8.4 mm to 17.0 ± 8.0 mm (t = -1.224 P = 0.049) and mean T1 tilt decreased from 4.9 ± 4.2 ° to 3.5 ± 3.1° (t = 2.913, P = 0.011). No significant improvement of radiographic parameters and HRQOL were observed in observation group.Conclusions:For AIS patients with a Risser 3-5 and a Cobb angle 20°-40°, Schroth exercises improved HRQOL and halted curve progression during the follow-up period. Both cervical spine alignment and shoulder balance were also significantly improved after Schroth exercises. We recommend Schroth exercises for patients with AIS.
简介:AbstractBackground:Patients’ recovery after surgery is the major concern for all perioperative clinicians. This study aims to minimize the side effects of peri-operative surgical stress and accelerate patients’ recovery of gastrointestinal (GI) function and quality of life after colorectal surgeries, an enhanced recovery protocol based on pre-operative rehabilitation was implemented and its effect was explored.Methods:A prospective randomized controlled clinical trial was conducted, patients were recruited from January 2018 to September 2019 in this study. Patients scheduled for elective colorectal surgeries were randomly allocated to receive either standardized enhanced recovery after surgery (S-ERAS) group or enhanced recovery after surgery based on pre-operative rehabilitation (group PR-ERAS). In the group PR-ERAS, on top of recommended peri-operative strategies for enhanced recovery, formatted rehabilitation exercises pre-operatively were carried out. The primary outcome was the quality of GI recovery measured with I-FEED scoring. Secondary outcomes were quality of life scores and strength of handgrip; the incidence of adverse events till 30 days post-operatively was also analyzed.Results:A total of 240 patients were scrutinized and 213 eligible patients were enrolled, who were randomly allocated to the group S-ERAS (n = 104) and group PR-ERAS (n = 109). The percentage of normal recovery graded by I-FEED scoring was higher in group PR-ERAS (79.0% vs. 64.3%, P < 0.050). The subscores of life ability and physical well-being at post-operative 72 h were significantly improved in the group PR-ERAS using quality of recovery score (QOR-40) questionnaire (P < 0.050). The strength of hand grip post-operatively was also improved in the group PR-ERAS (P < 0.050). The incidence of bowel-related and other adverse events was similar in both groups till 30 days post-operatively (P > 0.050).Conclusions:Peri-operative rehabilitation exercise might be another benevolent factor for early recovery of GI function and life of quality after colorectal surgery. Newer, more surgery-specific rehabilitation recovery protocol merits further exploration for these patients.Trial Registration:ChiCTR.org.cn, ChiCTR-ONRC-14005096
简介:AbstractBackground:Worldwide, the volume and availability of digestive endoscopy have undergone dramatic development in recent years, with increasing attention on quality assurance. We investigated the utilization and quality of digestive endoscopy in China from 2015 to 2019 and developed a quantitative quality evaluation tool for medical institutions.Methods:We invited all tertiary/secondary hospitals in Chinese mainland to participate in the survey annually. The questionnaires included the personnel, annual volume, and quality indicators of endoscopy. An endoscopy quality index (EQI) was developed based on recorded quality indicators using principal component analysis to determine the relative weight.Results:From 2015 to 2019, 806, 1412, 2644, 2468, and 2541 hospitals were respectively enrolled in this study. The average annual volume of endoscopy increased from 12,445 to 16,206 (1.30-fold) and from 2938 to 4255 (1.45-fold) in tertiary and secondary hospitals, respectively. The most obvious growth was observed in diagnostic colonoscopy (1.44-fold for all hospitals after standardization). The proportion of early cancer among all esophageal and gastric cancers during diagnostic esophagogastroduodenoscopy increased from 12.3% (55,210/448,861) to 17.7% (85,429/482,647) and from 11.4% (69,411/608,866) to 16.9% (107,192/634,235), respectively. The adenoma detection rate of diagnostic colonoscopy increased from 14.9% (2,118,123/14,215,592) to 19.3% (3,943,203/20,431,104). The EQI model included 12 quality indicators, incorporating 64.9% (7.792/12) of the total variance into one comprehensive index. According to the EQI measurements, the quality of endoscopy was higher in tertiary hospitals and hospitals in developed areas with higher volume or more endoscopists than that in other hospitals.Conclusions:Digestive endoscopy in China has developed considerably in recent years in terms of both volume and quality. The EQI is a promising tool to quantify the quality of endoscopy at different hospitals.