Malignant tumors originating from the middle ear are rare. The literature identifies chronic inflammation and Human Papillomavirus (HPV) infection as the most common risk factors. A CT scan to assess bony invasion and...Malignant tumors originating from the middle ear are rare. The literature identifies chronic inflammation and Human Papillomavirus (HPV) infection as the most common risk factors. A CT scan to assess bony invasion and an MRI to evaluate soft tissue involvement, depth of invasion, and perineural invasion, followed by a biopsy, are indispensable for diagnosis and treatment. There is no standard treatment for squamous cell carcinoma of the middle ear, however, most reported cases are treated with surgical resection followed by postoperative radiotherapy. Given the challenges of achieving complete surgical excision, radiotherapy plays a crucial role in controlling middle ear cancers, as demonstrated in our case. We present a case of squamous cell carcinoma of the middle ear in a 63-year-old female with a history of chronic suppurative otitis media. The patient underwent a right subtotal petrosectomy without lymph node dissection followed by concurrent chemoradiotherapy. At the one-year follow visit, no recurrence or metastasis was detected.展开更多
This case is a 49-year-old female patient who presented with suspected eustachian tube dysfunction symptoms that were refractory to medical treatment. She presented with conductive hearing loss and aural fullness on t...This case is a 49-year-old female patient who presented with suspected eustachian tube dysfunction symptoms that were refractory to medical treatment. She presented with conductive hearing loss and aural fullness on the left. A physical exam revealed an epitympanic fleshy mass in the middle ear with effusion. Imaging with MRI and CT showed opacification of the epitympanum with surrounding bony demineralization bilaterally left greater than right and significant thinning versus dehiscence of the tegmen mastoideum and tympani on the left with only thinning of the tegmen on the right. An MR temporal bone with and without contrast, demonstrated enhancement of the left middle ear extending to the tegmen and corresponding enhancement of the dura along the floor of the left middle cranial fossa as well as extending along foramen ovale into the infratemporal fossa. There was to a lesser degree similar appearance on the right. A biopsy of the middle ear mass on the left revealed meningioma. This case highlights the need to widen your differential with common symptoms when they are refractory to treatment.展开更多
The types,occurrence and composition of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata of the first member of the Middle Permian Maokou Formation(Mao-1 Member)in eastern Sichuan Basin w...The types,occurrence and composition of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata of the first member of the Middle Permian Maokou Formation(Mao-1 Member)in eastern Sichuan Basin were investigated through outcrop section measurement,core observation,thin section identification,argon ion polishing,X-ray diffraction,scanning electron microscope,energy spectrum analysis and laser ablation-inductively coupled plasma-mass spectrometry.The diagenetic evolution sequence of clay minerals was clarified,and the sedimentary-diagenetic evolution model of clay minerals was established.The results show that authigenic sepiolite minerals were precipitated in the Si4+and Mg2+-rich cool aragonite sea and sepiolite-bearing strata were formed in the Mao-1 Member.During burial diagenesis,authigenic clay minerals undergo two possible evolution sequences.First,from the early diagenetic stage A to the middle diagenetic stage A1,the sepiolite kept stable in the shallow-buried environment lack of Al3+.It began to transform into stevensite in the middle diagenetic stage A2,and then evolved into disordered talc in the middle diagenetic stage B1and finally into talc in the period from the middle diagenetic stage B2to the late diagenetic stage.Thus,the primary diagenetic evolution sequence of authigenic clay minerals,i.e.sepiolite-stevensite-disordered talc-talc,was formed in the Mao-1 Member.Second,in the early diagenetic stage A,as Al3+carried by the storm and upwelling currents was involved in the diagenetic process,trace of sepiolite started to evolve into smectite,and a part of smectite turned into chlorite.From the early diagenetic stage B to the middle diagenesis stage A1,a part of smectite evolved to illite/smectite mixed layer(I/S).The I/S evolved initially into illite from the middle diagenesis stage A2to the middle diagenesis stage B2,and then totally into illite in the late diagenesis stage.Thus,the secondary diagenetic evolution sequence of authigenic clay minerals,i.e.sepiolite-smectite-chlorite/illite,was formed in the Mao-1 Member.The types and evolution of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata are significant for petroleum geology in two aspects.First,sepiolite can adsorb and accumulate a large amount of organic matters,thereby effectively improving the quality and hydrocarbon generation potential of the source rocks of the Mao-1 Member.Second,the evolution from sepiolite to talc is accompanied by the formation of numerous organic matter pores and clay shrinkage pores/fractures,as well as the releasing of the Mg2+-rich diagenetic fluid,which allows for the dolomitization of limestone within or around the sag.As a result,the new assemblages of self-generation and self-accumulation,and lower/side source and upper/lateral reservoir,are created in the Middle Permian,enhancing the hydrocarbon accumulation efficiency.展开更多
Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remai...Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remains high.Therefore,exploring the molecular mechanisms underlying cholesteatoma is crucial for discovering new therapeutic approaches.This study aims to explore the involvement of N6-methyladenosine(m^(6)A)methylation in long non-coding RNAs(lncRNAs)in the biological functions and related pathways of middle ear cholesteatoma.Methods:The m^(6)A modification patterns of lncRNA in middle ear cholesteatoma tissues(n=5)and normal post-auricular skin tissues(n=5)were analyzed using an lncRNA m^(6)A transcriptome microarray.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses were conducted to identify potential biological functions and signaling pathways involved in the pathogenesis of middle ear cholesteatoma.Methylated RNA immunoprecipitation(MeRIP)-PCR was used to validate the m^(6)A modifications in cholesteatoma and normal skin tissues.Results:Compared with normal skin tissues,1525 lncRNAs were differentially methylated in middle ear cholesteatoma tissues,with 1048 showing hypermethylation and 477 showing hypomethylation[fold change(FC)≥3 or<1/3,P<0.05].GO enrichment analysis indicated that hypermethylated lncRNAs were involved in protein phosphatase inhibitor activity,neuron-neuron synapse,and regulation ofα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid(AMPA)receptor activity.Hypomethylated lncRNAs were associated with mRNA methyltransferase activity,secretory granule membrane,and mRNA methylation.KEGG analysis revealed that hypermethylated lncRNAs were mainly associated with 5 pathways:the Hedgehog signaling pathway,viral protein interaction with cytokines and cytokine receptors,mitogen-activated protein kinase(MAPK)signaling pathway,cytokine-cytokine receptor interaction,and adrenergic signaling in cardiomyocytes.Hypomethylated lncRNAs were mainly involved in 4 pathways:Renal cell carcinoma,tumor necrosis factor signaling pathway,transcriptional misregulation in cancer,and cytokine-cytokine receptor interaction.Additionally,MeRIP-PCR confirmed the changes in m^(6)A methylation levels in NR_033339,NR_122111,NR_130744,and NR_026800,consistent with microarray analysis.Real-time PCR also confirmed the significant upregulation of MAPK1 and NF-κB,key genes in the MAPK signaling pathway.Conclusion:This study reveals the m^(6)A modification patterns of lncRNAs in middle ear cholesteatoma,suggests a direction for further research into the role of lncRNA m^(6)A modification in the etiology of cholesteatoma.The findings provide potential therapeutic targets for the treatment of middle ear cholesteatoma.展开更多
Introduction: Middle ear surgery is increasingly performed in our department. Our goal was to take stock of this activity in the ENT department of the Donka National Hospital. Equipment and Methods: It was a descripti...Introduction: Middle ear surgery is increasingly performed in our department. Our goal was to take stock of this activity in the ENT department of the Donka National Hospital. Equipment and Methods: It was a descriptive and retrospective study;it involved 71 patients’ records operated from January 1, 2018 to December 31, 2023. We included the files of patients who had a middle ear surgery including the post-operative report and follow-up. Incomplete or illegible records were excluded. The parameters studied were epidemiological, otoscopic, tomodensitometric, surgical indications, surgical techniques and results. Results: We recorded 71 middle ear surgeries out of 548 ENT surgeries, the prevalence was 12.96%. The average age was 23 years (type-deviation = 17, 29 years) with extremes of 3 to 75 years. According to the preoperative audiometry, the deafness was medium (48.8%), mild (36.9%) and severe (14.3%). The operative indications were among others: perforation of the tympanic sequellar (52.5%), chronic otomastoiditis (23.8%), cholesteatoma (15%) and seromuqueous otitis (8.7%). We performed 70 tympanoplasties (90.9%), 50 mastoidectomies (64.9%) and 7 trans-tympanic aerators (9.1%). One month after surgery, the neotympanum was constituted in 86%, and the hearing gain was between 11 and 15 dB in 18.3% of cases. Conclusion: Middle ear surgery was infrequent. Young subjects are the most concerned. Tympanoplasty and mastoidectomy are the main surgical techniques. The anatomical and functional results are appreciable.展开更多
With the deepening of educational reform,interdisciplinary thematic learning,as an emerging educational model,has become a focus of attention in the field of educational research.Based on the STEM(science,technology,e...With the deepening of educational reform,interdisciplinary thematic learning,as an emerging educational model,has become a focus of attention in the field of educational research.Based on the STEM(science,technology,engineering,and mathematics)education concept and CASES-T(Content,Activity,Situation,Evaluation,Strategy-Target)model,this study provides a theoretical basis for the teaching design and implementation of interdisciplinary thematic learning in middle school physical education.Through the analysis of specific interdisciplinary thematic learning cases,it aims to provide theoretical support and practical guidance for the reform of middle school physical education through the CASES-T model-based interdisciplinary thematic teaching design research in middle school physical education,in order to enhance students’learning effects,cultivate core literacy in physical education,and promote students’all-round development.展开更多
The Hanjiang Formation of Langhian age (middle Miocene) in the Pearl River Mouth Basin (PRMB), South China Sea consists of deltaic siliciclastic and neritic shelf carbonate rhythmic alternations, which form one of...The Hanjiang Formation of Langhian age (middle Miocene) in the Pearl River Mouth Basin (PRMB), South China Sea consists of deltaic siliciclastic and neritic shelf carbonate rhythmic alternations, which form one of the potential reservoirs of the basin. To improve stratigraphic resolutions for hydrocarbon prospecting and exploration in the basin, the present study undertakes spectral analysis of high-resolution natural gamma-ray (NGR) well-logging record to determine the dominant frequency components and test whether Milankovitch orbital signals are recorded in rhythmic successions. Analytical results indicate the orbital cycles of precession (~19 ka and ~23 ka), obliquity (-41 ka), and eccentricity (~100 ka and --405 ka), which provide the strong evidence for astronomically driven climate changes in the rhythmic alternation successions. Within biochronological constraint, a high-resolution astronomical timescale was constructed through the astronomical tuning of the NGR record to recent astronomically calculated variation of Earth's orbit. The astronomically tuned timescale can be applied to calculate astronomical ages for the geological events and bioevents recognized throughout the period. The first downhole occurrences of foraminifers Globorotalia peripheroronda and Globigerinoides sicanus are dated at 14.546 Ma and 14.919 Ma, respectively, which are slightly different from earlier estimates in the South China Sea. When compared with the global sea-level change chart, the astronomical estimate for the sequences recognized based on microfossil distributions have the same end time but the different initiation time. This is probably due to the local or regional tectonic activities superimposed on eustatic rise which postponed the effect of global sea-level rising. Astronomical timescale also resolves the depositional evolution history for the Langhian Stage (middle Miocene) with a variation that strongly resembles that of Earth's orbital eccentricity predicted from 13.65 Ma to 15.97 Ma. We infer that the main factor controlling the variability of the sedimentation rate in the Hanjiang Formation is related to the ^-405-ka-period eccentricity.展开更多
After a review of learning strategy research in China and abroad, this paper made an investigation on the differences in use of learning strategies reported by urban and rural students from four middle schools in Zhan...After a review of learning strategy research in China and abroad, this paper made an investigation on the differences in use of learning strategies reported by urban and rural students from four middle schools in Zhanjiang city. The investigation revealed the following findings: urban students employ cognitive and social strategies more frequently than rural students; urban students reported a wider range of strategies compared with their rural peers; urban students of intermediate achievements employ more social strategies than their rural peers, while rural students use affective strategy significantly more often; urban and rural students reported different patterns of gender difference.展开更多
Aiming at a kind of middle ear implant(MEI), the driving voltage of a piezoelectric floating mass actuator is analyzed using a 0. 7Pb (Mg1/3Nb2/3) O3-0. 3PbTiO3 ( PMN- 30% PT)stack as a new type of vibrator. For...Aiming at a kind of middle ear implant(MEI), the driving voltage of a piezoelectric floating mass actuator is analyzed using a 0. 7Pb (Mg1/3Nb2/3) O3-0. 3PbTiO3 ( PMN- 30% PT)stack as a new type of vibrator. For the purpose of facilitating the analysis, a simplified coupling model of the ossicular chain and the piezoelectric actuator is constructed. First, a finite element model of a human middle ear is constructed by reverse engineering technology, and the validity of this model is confirmed by comparing the simulated motion of the stapes footplate obtained by this model with experimental measurements. Then the displacement impedance of the incus long process is analyzed, and a single mass-spring-damper equivalent model of the ossicular chain attached with the clamp is derived. Finally, a simplified coupling model of the ossicular chain and the piezoelectric actuator is established and used to analyze the driving voltage property of the actuator. The results show that the required driving voltage decreases with the increase in the frequency, and the maximum required driving voltage is 20. 9 V in the voice frequencies. However, in the mid-high frequencies where most sensorineural hearing loss occurs, the maximum required driving voltage is 3.8 V, which meets the low-voltage and low-power requirements of the MEI.展开更多
To overcome some of the problems inherent in conventional heating aids such as low gain at high fi'equencies due to acoustic feedback, discomfort in occlusion of the extemal ear canal and so on, implantable middle ea...To overcome some of the problems inherent in conventional heating aids such as low gain at high fi'equencies due to acoustic feedback, discomfort in occlusion of the extemal ear canal and so on, implantable middle ear hearing devices (IMEHDs) have been developed over the past two decades. For such kinds of IMEHDs, this paper presents the design of a floating mass piezoelectric actuator using a PMN-30%PT stack as a new type of vibrator. The proposed piezoelectric actuator consists of only three components of a piezoelectric stack, a metal case and a clamp. For the purpose of aiding the design of this actuator, a coupling biomechanics model of human middle ear and the piezoelectric actuator was constructed. This model was built based on a complete set of computerized tomography section images of a healthy volunteer's left ear by reverse engineering technology. The validity of this model was confirmed by comparing the motion of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones. It is shown that the designed actuator can be implanted on the incus long process by a simple surgical operation, and the stapes footplate displacement by its excitation at 10.5 V root-mean-square(RMS) voltage was equivalent to that from acoustic stimulation at 100 dB sound pressure level(SPL), which is adequate stimulation to the ossicular chain. The corresponding power consumption is 0.04 mW per volt of excitation at 1 kHz, which is low enough for the transducer to be used in an implantable middle ear device.展开更多
We present a very rare case of tophaceous gout of the middle ear causing conductive hearing loss,with special emphasis on Computed Tomography presentation.
Objectives: Facial nerve aberration is the most troublesome situation in congenital malformations of middle ear.The aim of our study is to investigate its imaging and clinical features as well as relevant choice of su...Objectives: Facial nerve aberration is the most troublesome situation in congenital malformations of middle ear.The aim of our study is to investigate its imaging and clinical features as well as relevant choice of surgical techniques for hearing improvement.Methods: A retrospective study involving review of clinical data of 227 patients(256 ears) with congenital middle ear anomaly was undertaken, including preoperative computed tomography(CT) data, surgical records and videos.Results: Aberration involving intratemporal facial nerve was found in 82/256 ears(32.03%) with congenital middle ear anomaly. The most common forms of aberration included overhanging over the oval window(50/82 ears, 60.98%), bifurcation(3/82 ears, 3.66%) and transverse over the promontory(3/82 ears, 3.66%), counting for 68.29%(56/82) of the cases with facial nerve aberration. Concomitant stapes malformation was found in 76/82 ears(92.68%) and atresia or stenosis of the oval window in 27/82 ears(32.93%). In 9/82 ears(10.98%) both stapes and oval window was absent. Elective surgeries for the purpose of hearing improvement included stapodotomy + piston implantation, labyrinthotomy, labyrinthotomy + total ossicular replacement prosthesis(TORP) implantation and Vibrant Soundbridge(VSB) implantation.Conclusion: The majority of facial nerve aberration in congenital malformation of middle ear involves displacement of facial nerve, in addition to concomitant malformations of the stapes and/or oval window, which may influence the choice of surgery for hearing improvement. VSB implantation may be considered as a useful option.展开更多
Hearing loss is a condition affecting millions of people worldwide. Conductive hearing loss (CHL) is mainly caused by middle ear diseases. The low frequency area is the pivotal part of speech frequencies and most freq...Hearing loss is a condition affecting millions of people worldwide. Conductive hearing loss (CHL) is mainly caused by middle ear diseases. The low frequency area is the pivotal part of speech frequencies and most frequently impaired in patients with CHL. Among various treatments of CHL, middle ear surgery is efficient to improve hearing. However, variable success rates and possible needs for prolonged revision surgery still frustrate both surgeons and patients. Nowadays, increasing numbers of researchers explore various methods to monitor the efficacy of ossicular reconstruction intraoperatively, including electrocochleography (ECochG), auditory brainstem response (ABR), auditory steady state response (ASSR), distortion product otoacoustic emissions (DPOAE), subjective whisper test, and optical coherence tomography (OCT). Here, we illustrate several methods used clinically by reviewing the literature.展开更多
There are complex and regular changes on sedimentary facies from the Early to the Middle Triassic in the Nanpanjiang basin. After the obvious drowned event of carbonate platforms in the transitional period between Per...There are complex and regular changes on sedimentary facies from the Early to the Middle Triassic in the Nanpanjiang basin. After the obvious drowned event of carbonate platforms in the transitional period between Permian and Triassic, carbonate platforms have evolved into the ramp type from the rimmed shelf type. The differentiation of sedimentary facies becomes clearer in space, which are marked by the changes from an attached platform to a turbidity basin and several isolated platforms in the basin. The striking characteristics are the development of oolitic banks on isolated platforms in Nanning and Jingxi and the reef and bank limestones in the margin of the attached platform in the Early Triassic. Despite the difference of the time span and the architecture of facies succession of third order sedimentary sequences, the process of the third order relative sea level changes reflected by the sedimentary facies succession of the third order sequences is generally synchronous. Therefore, six third order sequences could be discerned in the strata from the Early to the Middle Triassic in the Nanpanjiang basin. Using two types of facies changing surfaces and two types of diachronisms in stratigraphic records as the key elements, the sedimentary facies architectures of the third order sequences that represent sequence stratigraphic frameworks from the Early to the Middle Triassic in the Nanpanjiang basin could be constructed.展开更多
The principle of middle and long-term earthquake forecast model of spatial and temporal synthesized probability gain and the evaluation of forecast efficiency (R-values) of various forecast methods are introduced in t...The principle of middle and long-term earthquake forecast model of spatial and temporal synthesized probability gain and the evaluation of forecast efficiency (R-values) of various forecast methods are introduced in this paper. The R-value method, developed by Xu (1989), is further developed here, and can be applied to more complicated cases. Probability gains in spatial and/or temporal domains and the R-values for different forecast methods are estimated in North China. The synthesized probability gain is then estimated as an example.展开更多
Objectives To investigate pre-and post-total middle ear reconstruction bacteriological changes in order to facilitate prevention and treatment of surgical infections. Methods Specimens from 128 ears in 124 patients wi...Objectives To investigate pre-and post-total middle ear reconstruction bacteriological changes in order to facilitate prevention and treatment of surgical infections. Methods Specimens from 128 ears in 124 patients with problematic mastoid cavities who underwent revision total middle ear reconstruction were studied. Results Bacteriological tests were positive in 87(68.0%) pre-operative specimens, despite local treatment, and in 74 (57.8%) specimens collected 10 days after operation. Common organism strains in pre-and post-operative specimens were slightly different and included: coagulase-staphylococcus, GRAM+ rods, staphylococcus aureus, pseudomonas aeruginosa and fungi. At the time of patient discharge(15-20 days post-operative), only 3 ears (2.3%) were tested positive which responded well to and became dry after local treatment. At one year, 4 ears (3.1%) showed recurrent otorrhea which again responded to local treatment. Conclusion For infection of problematic mastoid cavities after an open cavity procedure, revision total middle ear reconstruction is effective in controlling infection and promoting a dry ear. Infection prevention and treatment is important considering the relatively high rates of peri-operative local infections.展开更多
Gout is the most common cause of monoarthritis in men occurring classically in the great toe and the knee.Extra-articular gout manifestations are rare.Only a few cases of head and neck urate crystals deposits have bee...Gout is the most common cause of monoarthritis in men occurring classically in the great toe and the knee.Extra-articular gout manifestations are rare.Only a few cases of head and neck urate crystals deposits have been described in the literature.Precipitations in the middle ear cause conductive hearing loss with common otoscopic anomalies and difficult imaging diagnosis.We report a case of a healthy 58-years-old man with a middle ear urate deposit causing a progressive hearing loss as the very first symptom of gout.The nature of the deposit was unsure on computer tomography(CT)due to atypical density.The final diagnosis was revealed after surgical procedure and histologic examination.A review of the literature is also presented.Seven cases of middle ear urate deposit as the first symptom of gout were found and compared.Progressive conductive hearing loss in middle-aged patients with abnormal otoscopy and middle ear atypical density mass on CT scan must lead to a minimal surgical procedure with a histologic examination to exclude urate crystals deposits.展开更多
Earthquake activities in history are characterized by active and quiet periods. In the quiet period, the place where earthquake M_≥6 occurred means more elastic energy store and speedy energy accumulation there. When...Earthquake activities in history are characterized by active and quiet periods. In the quiet period, the place where earthquake M_≥6 occurred means more elastic energy store and speedy energy accumulation there. When an active period of big earthquake activity appeared in wide region, in the place where earthquake (M_≥6) occurred in the past quiet period, the big earthquake with magnitude of 7 or more often occur there. We call the above-mentioned judgement for predicting big earthquake the 'criterion of activity in quiescence'. The criterion is relatively effective for predicting location of big earthquake. In general, error of predicting epicenter is no more than 100 km. According to the criterion, we made successfully a middle-term prediction on the 1996 Lijiang earthquake in Yunnan Province, the error of predicted location is about 50 km. Besides, the 1994 Taiwan strait earthquake (M_s=7.3), the 1995 Yunnan-Myanmar boundary earthquake (M_s=7.2) and the Mani earthquake (M_s=7.9) in north Tibet are accordant with the retrospective predictions by the 'criterion of activity in quiescence'. The windows of 'activity in quiescence' identified statistically by us are 1940-1945, 1958-1961 and 1979-1986. Using the 'criterion of activity in quiescence' to predict big earthquake in the mainland of China,the earthquake defined by 'activity in quiescence' has magnitude of 6 or more; For the Himalayas seismic belt, the Pacific seismic belt and the north-west boundary seismic belt of Xinjiang, the earthquake defined by 'activity in quiescence' has magnitude of 7, which is corresponding to earthquake with magnitude of much more than 7 in future. For the regions where there are not tectonically and historically a possibility of occurring big earthquake (M_s=7), the criterion of activity in quiescence is not effective.展开更多
The three-dimensional(3D)model of the middle ear is of great significance to the research of middle ear related diseases.The particular focus of this work is to simulate the impact of aircraft altitude and speed chang...The three-dimensional(3D)model of the middle ear is of great significance to the research of middle ear related diseases.The particular focus of this work is to simulate the impact of aircraft altitude and speed changes on the tympanic membrane(TM)during the descent phase,so as to analyze the pathogenesis of aero-otitis media and the mechanical response characteristics of TM under static pressure.The simulations showed that the stress and strain of TM increase as the altitude difference and speed of the aircraft increase,and the maximum stress and strain areas are consistent with the clinical observation of TM hyperemia.Therefore,among many prevention and treatment measures of aero-otitis media,it is a therapeutic method to directly balance the pressure difference between the inner and outer TM.展开更多
Congenital cholesteatoma(CC)is a rarely seen benign tumor of the temporal bone. There are five general sites of extradural occurrence: the middle ear, external auditory meatus, mastoid, squamous portion and the petr...Congenital cholesteatoma(CC)is a rarely seen benign tumor of the temporal bone. There are five general sites of extradural occurrence: the middle ear, external auditory meatus, mastoid, squamous portion and the petrous apex of the temporal bone. CC grows slowly and presents no symptoms at the early stage. Delayed and mis-diagnosis are common with this condition. Case report A 10-year-old boy presented with a 3-month history of hearing loss on right side. There was no history of otorrhea, facial palsy, previous otological procedures or trauma. Otoscopy revealed a bulging posterosuperior quadrant in the otherwise intact right tympanic membrane (Fig.1). Pure tone audiometry showed an average threshold of 51 dB for 500, 1000, 2000 and 4000Hz, with a 40 dB air-bone gap, suggesting a moderate conductive hearing loss(Fig.4). CT scan of the temporal bone showed an isolated soft tissue density lesion in the middle ear(Fig.2).展开更多
文摘Malignant tumors originating from the middle ear are rare. The literature identifies chronic inflammation and Human Papillomavirus (HPV) infection as the most common risk factors. A CT scan to assess bony invasion and an MRI to evaluate soft tissue involvement, depth of invasion, and perineural invasion, followed by a biopsy, are indispensable for diagnosis and treatment. There is no standard treatment for squamous cell carcinoma of the middle ear, however, most reported cases are treated with surgical resection followed by postoperative radiotherapy. Given the challenges of achieving complete surgical excision, radiotherapy plays a crucial role in controlling middle ear cancers, as demonstrated in our case. We present a case of squamous cell carcinoma of the middle ear in a 63-year-old female with a history of chronic suppurative otitis media. The patient underwent a right subtotal petrosectomy without lymph node dissection followed by concurrent chemoradiotherapy. At the one-year follow visit, no recurrence or metastasis was detected.
文摘This case is a 49-year-old female patient who presented with suspected eustachian tube dysfunction symptoms that were refractory to medical treatment. She presented with conductive hearing loss and aural fullness on the left. A physical exam revealed an epitympanic fleshy mass in the middle ear with effusion. Imaging with MRI and CT showed opacification of the epitympanum with surrounding bony demineralization bilaterally left greater than right and significant thinning versus dehiscence of the tegmen mastoideum and tympani on the left with only thinning of the tegmen on the right. An MR temporal bone with and without contrast, demonstrated enhancement of the left middle ear extending to the tegmen and corresponding enhancement of the dura along the floor of the left middle cranial fossa as well as extending along foramen ovale into the infratemporal fossa. There was to a lesser degree similar appearance on the right. A biopsy of the middle ear mass on the left revealed meningioma. This case highlights the need to widen your differential with common symptoms when they are refractory to treatment.
基金Supported by the Enterprise Innovation and Development Joint Fund of National Natural Science Foundation of China(U19B6003)National Natural Science Foundation of China(41872150)。
文摘The types,occurrence and composition of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata of the first member of the Middle Permian Maokou Formation(Mao-1 Member)in eastern Sichuan Basin were investigated through outcrop section measurement,core observation,thin section identification,argon ion polishing,X-ray diffraction,scanning electron microscope,energy spectrum analysis and laser ablation-inductively coupled plasma-mass spectrometry.The diagenetic evolution sequence of clay minerals was clarified,and the sedimentary-diagenetic evolution model of clay minerals was established.The results show that authigenic sepiolite minerals were precipitated in the Si4+and Mg2+-rich cool aragonite sea and sepiolite-bearing strata were formed in the Mao-1 Member.During burial diagenesis,authigenic clay minerals undergo two possible evolution sequences.First,from the early diagenetic stage A to the middle diagenetic stage A1,the sepiolite kept stable in the shallow-buried environment lack of Al3+.It began to transform into stevensite in the middle diagenetic stage A2,and then evolved into disordered talc in the middle diagenetic stage B1and finally into talc in the period from the middle diagenetic stage B2to the late diagenetic stage.Thus,the primary diagenetic evolution sequence of authigenic clay minerals,i.e.sepiolite-stevensite-disordered talc-talc,was formed in the Mao-1 Member.Second,in the early diagenetic stage A,as Al3+carried by the storm and upwelling currents was involved in the diagenetic process,trace of sepiolite started to evolve into smectite,and a part of smectite turned into chlorite.From the early diagenetic stage B to the middle diagenesis stage A1,a part of smectite evolved to illite/smectite mixed layer(I/S).The I/S evolved initially into illite from the middle diagenesis stage A2to the middle diagenesis stage B2,and then totally into illite in the late diagenesis stage.Thus,the secondary diagenetic evolution sequence of authigenic clay minerals,i.e.sepiolite-smectite-chlorite/illite,was formed in the Mao-1 Member.The types and evolution of authigenic clay minerals in argillaceous limestone of sepiolite-bearing strata are significant for petroleum geology in two aspects.First,sepiolite can adsorb and accumulate a large amount of organic matters,thereby effectively improving the quality and hydrocarbon generation potential of the source rocks of the Mao-1 Member.Second,the evolution from sepiolite to talc is accompanied by the formation of numerous organic matter pores and clay shrinkage pores/fractures,as well as the releasing of the Mg2+-rich diagenetic fluid,which allows for the dolomitization of limestone within or around the sag.As a result,the new assemblages of self-generation and self-accumulation,and lower/side source and upper/lateral reservoir,are created in the Middle Permian,enhancing the hydrocarbon accumulation efficiency.
基金supported by the National Natural Science Foundation(82071036,82000973)the Natural Science Foundation of Hunan Province(2022JJ30821,2019JJ50967)the Special Project for the Construction of Innovative Provinces in Hunan Province(2023SK4030),China。
文摘Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remains high.Therefore,exploring the molecular mechanisms underlying cholesteatoma is crucial for discovering new therapeutic approaches.This study aims to explore the involvement of N6-methyladenosine(m^(6)A)methylation in long non-coding RNAs(lncRNAs)in the biological functions and related pathways of middle ear cholesteatoma.Methods:The m^(6)A modification patterns of lncRNA in middle ear cholesteatoma tissues(n=5)and normal post-auricular skin tissues(n=5)were analyzed using an lncRNA m^(6)A transcriptome microarray.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses were conducted to identify potential biological functions and signaling pathways involved in the pathogenesis of middle ear cholesteatoma.Methylated RNA immunoprecipitation(MeRIP)-PCR was used to validate the m^(6)A modifications in cholesteatoma and normal skin tissues.Results:Compared with normal skin tissues,1525 lncRNAs were differentially methylated in middle ear cholesteatoma tissues,with 1048 showing hypermethylation and 477 showing hypomethylation[fold change(FC)≥3 or<1/3,P<0.05].GO enrichment analysis indicated that hypermethylated lncRNAs were involved in protein phosphatase inhibitor activity,neuron-neuron synapse,and regulation ofα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid(AMPA)receptor activity.Hypomethylated lncRNAs were associated with mRNA methyltransferase activity,secretory granule membrane,and mRNA methylation.KEGG analysis revealed that hypermethylated lncRNAs were mainly associated with 5 pathways:the Hedgehog signaling pathway,viral protein interaction with cytokines and cytokine receptors,mitogen-activated protein kinase(MAPK)signaling pathway,cytokine-cytokine receptor interaction,and adrenergic signaling in cardiomyocytes.Hypomethylated lncRNAs were mainly involved in 4 pathways:Renal cell carcinoma,tumor necrosis factor signaling pathway,transcriptional misregulation in cancer,and cytokine-cytokine receptor interaction.Additionally,MeRIP-PCR confirmed the changes in m^(6)A methylation levels in NR_033339,NR_122111,NR_130744,and NR_026800,consistent with microarray analysis.Real-time PCR also confirmed the significant upregulation of MAPK1 and NF-κB,key genes in the MAPK signaling pathway.Conclusion:This study reveals the m^(6)A modification patterns of lncRNAs in middle ear cholesteatoma,suggests a direction for further research into the role of lncRNA m^(6)A modification in the etiology of cholesteatoma.The findings provide potential therapeutic targets for the treatment of middle ear cholesteatoma.
文摘Introduction: Middle ear surgery is increasingly performed in our department. Our goal was to take stock of this activity in the ENT department of the Donka National Hospital. Equipment and Methods: It was a descriptive and retrospective study;it involved 71 patients’ records operated from January 1, 2018 to December 31, 2023. We included the files of patients who had a middle ear surgery including the post-operative report and follow-up. Incomplete or illegible records were excluded. The parameters studied were epidemiological, otoscopic, tomodensitometric, surgical indications, surgical techniques and results. Results: We recorded 71 middle ear surgeries out of 548 ENT surgeries, the prevalence was 12.96%. The average age was 23 years (type-deviation = 17, 29 years) with extremes of 3 to 75 years. According to the preoperative audiometry, the deafness was medium (48.8%), mild (36.9%) and severe (14.3%). The operative indications were among others: perforation of the tympanic sequellar (52.5%), chronic otomastoiditis (23.8%), cholesteatoma (15%) and seromuqueous otitis (8.7%). We performed 70 tympanoplasties (90.9%), 50 mastoidectomies (64.9%) and 7 trans-tympanic aerators (9.1%). One month after surgery, the neotympanum was constituted in 86%, and the hearing gain was between 11 and 15 dB in 18.3% of cases. Conclusion: Middle ear surgery was infrequent. Young subjects are the most concerned. Tympanoplasty and mastoidectomy are the main surgical techniques. The anatomical and functional results are appreciable.
文摘With the deepening of educational reform,interdisciplinary thematic learning,as an emerging educational model,has become a focus of attention in the field of educational research.Based on the STEM(science,technology,engineering,and mathematics)education concept and CASES-T(Content,Activity,Situation,Evaluation,Strategy-Target)model,this study provides a theoretical basis for the teaching design and implementation of interdisciplinary thematic learning in middle school physical education.Through the analysis of specific interdisciplinary thematic learning cases,it aims to provide theoretical support and practical guidance for the reform of middle school physical education through the CASES-T model-based interdisciplinary thematic teaching design research in middle school physical education,in order to enhance students’learning effects,cultivate core literacy in physical education,and promote students’all-round development.
基金supported by Australian Research Council discovery grant(DP0770938 to ZQC)National Science and Technology Major Project (2011ZX05001-001-006)
文摘The Hanjiang Formation of Langhian age (middle Miocene) in the Pearl River Mouth Basin (PRMB), South China Sea consists of deltaic siliciclastic and neritic shelf carbonate rhythmic alternations, which form one of the potential reservoirs of the basin. To improve stratigraphic resolutions for hydrocarbon prospecting and exploration in the basin, the present study undertakes spectral analysis of high-resolution natural gamma-ray (NGR) well-logging record to determine the dominant frequency components and test whether Milankovitch orbital signals are recorded in rhythmic successions. Analytical results indicate the orbital cycles of precession (~19 ka and ~23 ka), obliquity (-41 ka), and eccentricity (~100 ka and --405 ka), which provide the strong evidence for astronomically driven climate changes in the rhythmic alternation successions. Within biochronological constraint, a high-resolution astronomical timescale was constructed through the astronomical tuning of the NGR record to recent astronomically calculated variation of Earth's orbit. The astronomically tuned timescale can be applied to calculate astronomical ages for the geological events and bioevents recognized throughout the period. The first downhole occurrences of foraminifers Globorotalia peripheroronda and Globigerinoides sicanus are dated at 14.546 Ma and 14.919 Ma, respectively, which are slightly different from earlier estimates in the South China Sea. When compared with the global sea-level change chart, the astronomical estimate for the sequences recognized based on microfossil distributions have the same end time but the different initiation time. This is probably due to the local or regional tectonic activities superimposed on eustatic rise which postponed the effect of global sea-level rising. Astronomical timescale also resolves the depositional evolution history for the Langhian Stage (middle Miocene) with a variation that strongly resembles that of Earth's orbital eccentricity predicted from 13.65 Ma to 15.97 Ma. We infer that the main factor controlling the variability of the sedimentation rate in the Hanjiang Formation is related to the ^-405-ka-period eccentricity.
文摘After a review of learning strategy research in China and abroad, this paper made an investigation on the differences in use of learning strategies reported by urban and rural students from four middle schools in Zhanjiang city. The investigation revealed the following findings: urban students employ cognitive and social strategies more frequently than rural students; urban students reported a wider range of strategies compared with their rural peers; urban students of intermediate achievements employ more social strategies than their rural peers, while rural students use affective strategy significantly more often; urban and rural students reported different patterns of gender difference.
基金The National Natural Science Foundation of China(No10772121)the Med-Science Cross Research Foundation of Shanghai Jiao-tong University (NoYG2007MS14)
文摘Aiming at a kind of middle ear implant(MEI), the driving voltage of a piezoelectric floating mass actuator is analyzed using a 0. 7Pb (Mg1/3Nb2/3) O3-0. 3PbTiO3 ( PMN- 30% PT)stack as a new type of vibrator. For the purpose of facilitating the analysis, a simplified coupling model of the ossicular chain and the piezoelectric actuator is constructed. First, a finite element model of a human middle ear is constructed by reverse engineering technology, and the validity of this model is confirmed by comparing the simulated motion of the stapes footplate obtained by this model with experimental measurements. Then the displacement impedance of the incus long process is analyzed, and a single mass-spring-damper equivalent model of the ossicular chain attached with the clamp is derived. Finally, a simplified coupling model of the ossicular chain and the piezoelectric actuator is established and used to analyze the driving voltage property of the actuator. The results show that the required driving voltage decreases with the increase in the frequency, and the maximum required driving voltage is 20. 9 V in the voice frequencies. However, in the mid-high frequencies where most sensorineural hearing loss occurs, the maximum required driving voltage is 3.8 V, which meets the low-voltage and low-power requirements of the MEI.
基金supported by National Natural Science Foundation of China (Grant No. 10772121)
文摘To overcome some of the problems inherent in conventional heating aids such as low gain at high fi'equencies due to acoustic feedback, discomfort in occlusion of the extemal ear canal and so on, implantable middle ear hearing devices (IMEHDs) have been developed over the past two decades. For such kinds of IMEHDs, this paper presents the design of a floating mass piezoelectric actuator using a PMN-30%PT stack as a new type of vibrator. The proposed piezoelectric actuator consists of only three components of a piezoelectric stack, a metal case and a clamp. For the purpose of aiding the design of this actuator, a coupling biomechanics model of human middle ear and the piezoelectric actuator was constructed. This model was built based on a complete set of computerized tomography section images of a healthy volunteer's left ear by reverse engineering technology. The validity of this model was confirmed by comparing the motion of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones. It is shown that the designed actuator can be implanted on the incus long process by a simple surgical operation, and the stapes footplate displacement by its excitation at 10.5 V root-mean-square(RMS) voltage was equivalent to that from acoustic stimulation at 100 dB sound pressure level(SPL), which is adequate stimulation to the ossicular chain. The corresponding power consumption is 0.04 mW per volt of excitation at 1 kHz, which is low enough for the transducer to be used in an implantable middle ear device.
文摘We present a very rare case of tophaceous gout of the middle ear causing conductive hearing loss,with special emphasis on Computed Tomography presentation.
基金supported by Beijing Municipal Science&Technology Commission(No.2171100001017079)for Prof. Shouqin Zhao
文摘Objectives: Facial nerve aberration is the most troublesome situation in congenital malformations of middle ear.The aim of our study is to investigate its imaging and clinical features as well as relevant choice of surgical techniques for hearing improvement.Methods: A retrospective study involving review of clinical data of 227 patients(256 ears) with congenital middle ear anomaly was undertaken, including preoperative computed tomography(CT) data, surgical records and videos.Results: Aberration involving intratemporal facial nerve was found in 82/256 ears(32.03%) with congenital middle ear anomaly. The most common forms of aberration included overhanging over the oval window(50/82 ears, 60.98%), bifurcation(3/82 ears, 3.66%) and transverse over the promontory(3/82 ears, 3.66%), counting for 68.29%(56/82) of the cases with facial nerve aberration. Concomitant stapes malformation was found in 76/82 ears(92.68%) and atresia or stenosis of the oval window in 27/82 ears(32.93%). In 9/82 ears(10.98%) both stapes and oval window was absent. Elective surgeries for the purpose of hearing improvement included stapodotomy + piston implantation, labyrinthotomy, labyrinthotomy + total ossicular replacement prosthesis(TORP) implantation and Vibrant Soundbridge(VSB) implantation.Conclusion: The majority of facial nerve aberration in congenital malformation of middle ear involves displacement of facial nerve, in addition to concomitant malformations of the stapes and/or oval window, which may influence the choice of surgery for hearing improvement. VSB implantation may be considered as a useful option.
基金supported by grants from Provincial Natural Science Foundation of Hai Nan (No. 20168349)the Clinical Research Supporting Foundation of PLA General Hospital (2016FC-TSYS-1014)National Basic Research Program of China (973 Program) (No. 2012CB967900) and National Basic Research Program of China (973 Program) (No. 2011CBA01000)
文摘Hearing loss is a condition affecting millions of people worldwide. Conductive hearing loss (CHL) is mainly caused by middle ear diseases. The low frequency area is the pivotal part of speech frequencies and most frequently impaired in patients with CHL. Among various treatments of CHL, middle ear surgery is efficient to improve hearing. However, variable success rates and possible needs for prolonged revision surgery still frustrate both surgeons and patients. Nowadays, increasing numbers of researchers explore various methods to monitor the efficacy of ossicular reconstruction intraoperatively, including electrocochleography (ECochG), auditory brainstem response (ABR), auditory steady state response (ASSR), distortion product otoacoustic emissions (DPOAE), subjective whisper test, and optical coherence tomography (OCT). Here, we illustrate several methods used clinically by reviewing the literature.
基金ThestudyisjointlysupportedbytheChinaPetroleumCorporation (No .NPJ- 10 0 19)andalsobytheMinistryofScienceandTechnology (SSER)
文摘There are complex and regular changes on sedimentary facies from the Early to the Middle Triassic in the Nanpanjiang basin. After the obvious drowned event of carbonate platforms in the transitional period between Permian and Triassic, carbonate platforms have evolved into the ramp type from the rimmed shelf type. The differentiation of sedimentary facies becomes clearer in space, which are marked by the changes from an attached platform to a turbidity basin and several isolated platforms in the basin. The striking characteristics are the development of oolitic banks on isolated platforms in Nanning and Jingxi and the reef and bank limestones in the margin of the attached platform in the Early Triassic. Despite the difference of the time span and the architecture of facies succession of third order sedimentary sequences, the process of the third order relative sea level changes reflected by the sedimentary facies succession of the third order sequences is generally synchronous. Therefore, six third order sequences could be discerned in the strata from the Early to the Middle Triassic in the Nanpanjiang basin. Using two types of facies changing surfaces and two types of diachronisms in stratigraphic records as the key elements, the sedimentary facies architectures of the third order sequences that represent sequence stratigraphic frameworks from the Early to the Middle Triassic in the Nanpanjiang basin could be constructed.
文摘The principle of middle and long-term earthquake forecast model of spatial and temporal synthesized probability gain and the evaluation of forecast efficiency (R-values) of various forecast methods are introduced in this paper. The R-value method, developed by Xu (1989), is further developed here, and can be applied to more complicated cases. Probability gains in spatial and/or temporal domains and the R-values for different forecast methods are estimated in North China. The synthesized probability gain is then estimated as an example.
文摘Objectives To investigate pre-and post-total middle ear reconstruction bacteriological changes in order to facilitate prevention and treatment of surgical infections. Methods Specimens from 128 ears in 124 patients with problematic mastoid cavities who underwent revision total middle ear reconstruction were studied. Results Bacteriological tests were positive in 87(68.0%) pre-operative specimens, despite local treatment, and in 74 (57.8%) specimens collected 10 days after operation. Common organism strains in pre-and post-operative specimens were slightly different and included: coagulase-staphylococcus, GRAM+ rods, staphylococcus aureus, pseudomonas aeruginosa and fungi. At the time of patient discharge(15-20 days post-operative), only 3 ears (2.3%) were tested positive which responded well to and became dry after local treatment. At one year, 4 ears (3.1%) showed recurrent otorrhea which again responded to local treatment. Conclusion For infection of problematic mastoid cavities after an open cavity procedure, revision total middle ear reconstruction is effective in controlling infection and promoting a dry ear. Infection prevention and treatment is important considering the relatively high rates of peri-operative local infections.
文摘Gout is the most common cause of monoarthritis in men occurring classically in the great toe and the knee.Extra-articular gout manifestations are rare.Only a few cases of head and neck urate crystals deposits have been described in the literature.Precipitations in the middle ear cause conductive hearing loss with common otoscopic anomalies and difficult imaging diagnosis.We report a case of a healthy 58-years-old man with a middle ear urate deposit causing a progressive hearing loss as the very first symptom of gout.The nature of the deposit was unsure on computer tomography(CT)due to atypical density.The final diagnosis was revealed after surgical procedure and histologic examination.A review of the literature is also presented.Seven cases of middle ear urate deposit as the first symptom of gout were found and compared.Progressive conductive hearing loss in middle-aged patients with abnormal otoscopy and middle ear atypical density mass on CT scan must lead to a minimal surgical procedure with a histologic examination to exclude urate crystals deposits.
基金State Natural Science Foundation of China!(49674210).
文摘Earthquake activities in history are characterized by active and quiet periods. In the quiet period, the place where earthquake M_≥6 occurred means more elastic energy store and speedy energy accumulation there. When an active period of big earthquake activity appeared in wide region, in the place where earthquake (M_≥6) occurred in the past quiet period, the big earthquake with magnitude of 7 or more often occur there. We call the above-mentioned judgement for predicting big earthquake the 'criterion of activity in quiescence'. The criterion is relatively effective for predicting location of big earthquake. In general, error of predicting epicenter is no more than 100 km. According to the criterion, we made successfully a middle-term prediction on the 1996 Lijiang earthquake in Yunnan Province, the error of predicted location is about 50 km. Besides, the 1994 Taiwan strait earthquake (M_s=7.3), the 1995 Yunnan-Myanmar boundary earthquake (M_s=7.2) and the Mani earthquake (M_s=7.9) in north Tibet are accordant with the retrospective predictions by the 'criterion of activity in quiescence'. The windows of 'activity in quiescence' identified statistically by us are 1940-1945, 1958-1961 and 1979-1986. Using the 'criterion of activity in quiescence' to predict big earthquake in the mainland of China,the earthquake defined by 'activity in quiescence' has magnitude of 6 or more; For the Himalayas seismic belt, the Pacific seismic belt and the north-west boundary seismic belt of Xinjiang, the earthquake defined by 'activity in quiescence' has magnitude of 7, which is corresponding to earthquake with magnitude of much more than 7 in future. For the regions where there are not tectonically and historically a possibility of occurring big earthquake (M_s=7), the criterion of activity in quiescence is not effective.
基金supported by the National Natural Science Foundation of China(Grant Nos.11772087 and 12172082)。
文摘The three-dimensional(3D)model of the middle ear is of great significance to the research of middle ear related diseases.The particular focus of this work is to simulate the impact of aircraft altitude and speed changes on the tympanic membrane(TM)during the descent phase,so as to analyze the pathogenesis of aero-otitis media and the mechanical response characteristics of TM under static pressure.The simulations showed that the stress and strain of TM increase as the altitude difference and speed of the aircraft increase,and the maximum stress and strain areas are consistent with the clinical observation of TM hyperemia.Therefore,among many prevention and treatment measures of aero-otitis media,it is a therapeutic method to directly balance the pressure difference between the inner and outer TM.
文摘Congenital cholesteatoma(CC)is a rarely seen benign tumor of the temporal bone. There are five general sites of extradural occurrence: the middle ear, external auditory meatus, mastoid, squamous portion and the petrous apex of the temporal bone. CC grows slowly and presents no symptoms at the early stage. Delayed and mis-diagnosis are common with this condition. Case report A 10-year-old boy presented with a 3-month history of hearing loss on right side. There was no history of otorrhea, facial palsy, previous otological procedures or trauma. Otoscopy revealed a bulging posterosuperior quadrant in the otherwise intact right tympanic membrane (Fig.1). Pure tone audiometry showed an average threshold of 51 dB for 500, 1000, 2000 and 4000Hz, with a 40 dB air-bone gap, suggesting a moderate conductive hearing loss(Fig.4). CT scan of the temporal bone showed an isolated soft tissue density lesion in the middle ear(Fig.2).