简介:Octave-spanningfrequencycombgenerationinmicroresonatorsispromising,butstrongspectrallossescausedbymaterialabsorptionandmodecouplingbetweentwopolarizationsormodefamiliescanbedetrimental.Weexaminetheimpactofthespectrallossandproposerobustcombgenerationwithalossofeven300dB/cm.CavitynonlineardynamicsshowthataphasechangeassociatedwithspectrallossescanfacilitatephasematchingandKerrcombgeneration.Giventhisuniquecapability,weproposeanovelarchitectureofon-chipspectroscopysystems.
简介:ObjectsToinvestigatetheextentofhearinglossinanelderlysamplepopulationtoestimatehearingdisordersamongtheage-equivalentpopulationinChinaandtostudyprimaryclinicalcharacteristicsofpresbycusis.MethodsClinicaldatafrom110hearinglosspatientsofbothseniumandpre-seniumages(95malesand15females,meanage=74.4±12.1years)werereviewed.Patientsagedfrom50to59yearswereacceptedasthepre-seniumcontrolgroup(n=15).The95seniumpatients(>60yearsofage)weredividedinto4groupsaccordingtoage:60+group(60to69years,n=25),70+group(70to79years,n=26),80+group(80to89years,n=32)and90+group(90yearsorolder,n=12).Puretoneaudiometrythresholdsweremeasuredinall110patients.HearinglossseverityofeachtestedearwasratedaccordingtotheGoodmanclassificationcriteria.Besides,audiometricconfigurationwasexaminedineachear.ResultsAudiometrictestingshowednormalhearingin65ears(29.5%),slighttomoderatelyseverehearinglossin131ears(59.5%),andsevereandprofoundlossin24ears(11%).Air-bonegapswerefoundin12ears(5.45%)indicatingconductivehearingloss.Exceptthe12earswithconductivehearingloss,audiogramsshowedgraduallyslopinglossin99ears(45%),sharplyslopinglossin34ears(15.45%),flatlossin45ears(20.45%),notchpatternlossin5ears(2.27%),troughandrisingpatternlossin2ears(0.91%),totaldeafnessin2ears(0.91%),andnormalhearingin21ears(9.55%).Onaverage,hearingthresholdsincreasedatarateofapproximately10dBper10yearforsubjectsaged60andolder.ConclusionsHearingthresholdstendtobestableinpresbycusispatientsagedfrom50to70years,increasesignificantlybetween70and80yearsofage,andreachanotherstablestageathighlevelsafter80yearsofage,especiallyinhighfrequencies.Hearinglossinmiddlefrequenciesaccountsformostofrecessioninloudnessperception.
简介:湿氧化过程,即,Walkley黑(WB)方法,是为土壤有机物(SOM)的决心的一个平淡、相对精确、流行的方法,但是它是费时间的,昂贵并且也,因为铬和强壮的酸的处理,引起环境污染的一个高潜力在这分析使用了。因此,loss-on-ignition(LOI)过程,为SOM评价的一个简单、便宜的方法,也避免铬的酸浪费,值得更多的注意。这研究的目的与LOI(SOMLOI)和WB(SOMWB)方法学习在SOM之间的统计关系决心在二个主要平原,Shahrekord和Koohrang平原比较SOM的空间可变性,Chaharmahal-va-Bakhtiari省,伊朗。五十件表面土壤样品(025厘米)随机在每个平原被收集在300,360,400,500和550慨杮慥汢?漨?捡楴敶?慃愠摮?用WB方法和LOI过程决定SOM?愠摮琠瑯污?愠摮??慨?潰楳楴敶挠牯敲慬楴湯?楷桴丠???摡潳灲楴湯
简介:AbstractBackground:Sudden sensorineural hearing loss (SSHL) refers to the sudden occurrence of unexplained sensorineural hearing loss. The present study showed that different systemic diseases had different influence on the occurrence and hearing outcome of SSHL. Thyroid hormone is one of the important factors for the development of fetal ear and auditory function. However, the distribution of thyroid dysfunction in SSHL patients and the effect of thyroid dysfunction on the occurrence and hearing outcome of SSHL has not been studied.Methods:In this study, a retrospective analysis had been done in 676 patients with SSHL. We had described the distribution of thyroid function in patients with SSHL in detail, and by the statistical method, analyzed the relationship between the hearing outcome and thyroid dysfunction, respectively.Results:In all patients, 24.41% (165/676) had abnormal thyroid function testing results. The onset age of SSHL in FT3 abnormal group (including low and high group) was younger than that in normal FT3 group. Recovery group had more patients with lower-than-normal T3 level as compared to non-recovery patients. Significant associations between T3 levels and hearing outcome were observed in the subgroup with longer time elapse between symptom onset and treatment (≥14 d).Conclusion:The incidence of thyroid dysfunction in SSHL is significantly higher than in the general population. There was obvious relationship between T3 and FT3 item of thyroid dysfunction and the onset time and hearing outcome of SSHL, which indicated that T3 or FT3 indicator may be one of the affecting factors for the SSHL. Early screening and diagnosis of thyroid dysfunction, especial T3 level, may help to evaluate the prognosis in SSHL patients.