Definition and Clinical Implication of Temporal Fine Structure / 대한이비인후과학회지

Perception of sound is associated with the use of multiple acoustic cues in the human auditory system. These acoustic cues can be classified by their temporal and spectral properties. Temporal information can be considered as a slowly varying envelope (ENV) superimposed on a more rapid temporal fine structure (TFS). Various sound-processing techniques have been developed to assess the role of acoustic information carried by temporal ENV and TFS information. Previous studies demonstrated that ENV cues are associated with speech recognition in quiet, while TFS cues have a role to melody/pitch perception and listening to speech in a competing background noise. Besides, a number of studies have shown that the relative insensitivity of hearing-impaired subjects to TFS information. Although current technologies used in cochlear implants are not efficient in delivering the TFS cues, new speech processing strategies have been proposed to deliver TFS information. We herein review the cutting edge of TFS related studies and discuss the clinical implication of TFS.

The Effect of Temporal Information in Cochlear Implant Analog Sounds on the Tone Recognition of Normal Hearing Young People / 听力学及言语疾病杂志

Objective By comparing the tone recognition rates for different cochlear implant (CI) analog sounds ,the effects of the temporal coding strategy on tone recognition were investigated .Methods The professional announcer read 6 vowel (/a/,/o/,/e/,/i/,/u/,/ü/) of 4 different tones at a normal speed .After adjusting the am-plitude envelope and increasing the fine structure ,the audios with different sampling accuracy below 500 Hz(125 ,250? ?1500 pps) were obtained ,including 288 audio amplitude envelope adjusted and 288 not adjusted .Thirty young participants of normal hearing had tone recognition tests .The results and the tone recognition rates under two dif-ferent temporal properties were compared .Results When the temporal fine structures were combined in considera-tion ,the amplitude envelope as adjusted to match the fundamental frequency (F0) had a significant effect on the tone recognition .The tone recognition rate after amplitude envelope adjusted (80 .22％ ± 16 .32％ ) was higher than before (74 .83％ ± 20 .24％ ) [F(1 ,9)=16 .91 ,P=0 .002] .When the amplitude envelopes were combined in consider-ation ,changing the fine structure of the frequency below 500 Hz had a significant effect on the tone recognition [F (11 ,99)=38 .86 ,P<0 .001] .When the sampling precision was <375 pps ,the tone recognition had improved re-markably with the improvement of sampling precision (P<0 .004) .When the sampling precision was ≥375 pps , the effect on the tone recognition was not significant (P>0 .004) .The interaction between changing amplitude en-velopes and increasing the fine structure had a significant effect on the tone recognition [ F(11 ,99 )= 3 .78 , P<0 .001] .When the fine structure ≤375 pps ,adjustment on the amplitude envelope to increase the information of F0 had a significant impact on the tone recognition (P<0 .05) .When the fine structure was >375 pps ,the difference of the tone recognition before and after the adjustment tended to 0 (P>0 .05) .Conclusion In the CI coding strate-gy ,adjusting the amplitude envelope to get more F0 information improves tone recognition .To a certain degree ,the tone recognition improves when the sampling precision of frequency below 500 Hz is improved .Adjusting the ampli-tude envelope to F0 and increasing the temporal fine structure below 500 Hz can be combined in the same speech coding strategy to optimize the tone recognition .

Speech intelligibility under noise conditions in sensorineural hearing-impaired / 中国耳鼻咽喉头颈外科

OBJECTIVE To study the impacts of different noise patterns on speech perception in normal hearing subjects and patients with sensorineural hearing loss. METHODS Mandarin Hearing in Noise Test for Children was played by MATLAB software in this study. The speech intelligibility of 25 normal hearing subjects and 20 patients with sensorineural hearing loss in quiet, speech-shaped noise and two-talker babbles were tested. The differences between normal hearing subjects and patients with sensorineural hearing loss in quiet and noise conditions were analyzed. RESULTS With the decrease of signal-to-noise ratios, the speech intelligibility of normal hearing subjects in speech-shaped noise pattern was declining more severely compared with the two-talker babbles pattern but there were no significant differences between them (P＞0.05). There were significant statistical differences in speech intelligibility under quiet, speech-shaped noise and two-talker babbles at 5 dB SNR (

What Is Temporal Fine Structure and Why Is It Important?

Complex sound like speech can be characterized as the sum of number of amplitude-modulated signals representing the outputs of an array of narrow frequency bands. Temporal information at the output of each band can be separated into temporal fine structure (TFS), the rapid oscillations close to the center frequency and temporal envelope (ENV), slower amplitude modulations superimposed on the TFS. TFS information can be carried in the pattern of phase locking to the stimulus waveform, while ENV by the changes in firing rate over time. The relative importance of temporal ENV and TFS information in understanding speech has been studied using various sound-processing techniques. A number of studies demonstrated that ENV cues are associated with speech recognition in quiet, while TFS cues are possibly linked to melody/pitch perception and listening to speech in a competing background. However, there are evidences that recovered ENV from TFS as well as TFS itself may be partially responsible for speech recognition. Current technologies used in cochlear implants (CI) are not efficient in delivering the TFS cues, and new attempts have been made to deliver TFS information into sound-processing strategy in CI. We herein discuss the current updated findings of TFS with a literature review.

Oxidation is Key for Black Carbon Surface Functionality and Nutrient Retention in Amazon Anthrosols.

Aims: Soil black carbon (BC) has been shown to possess large amounts of cation exchange sites and surface charge, and is viewed as a potential soil amendment to improve nutrient retention and for pollutant remediation. This study investigated the nanoscale distribution of reactive functional groups and the binding of cations on the surface of micron-size BC particles, identified the key processes, and explored the sources of surface functionality and their relative contribution to cation exchange capacity (CEC). Materials and Methods: Elemental microprobe and synchrotron-based Scanning Transmission X-ray Spectromicroscopy (STXM) coupled with Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy were used for nano-scale mapping of cations and reactive functional groups, and further distinction of the sources of reactive functional groups generated either by oxidation of BC surfaces or by adsorption of non- BC organic matter onto the BC surfaces. Their respective contribution to cation adsorption was obtained using a depth profile of a BC-rich Anthrosol from the central Amazon, Brazil. Results and Discussion: Adsorption of Non-BC organic matter is more dominant on the surface of BC particle in topsoil as evidenced by a stronger signal of microbial biomass and humic substances extracts. In comparison, a greater level of oxidation was found on the outerlayer of BC particles in subsoil horizons. Organic C in subsoils was found to generate 23-42% more CEC per unit C than topsoil. Based on CEC per unit C, the capacity of BC in creating CEC was 6-7 times higher than Non-BC, and the BC in deeper horizons had up to 20% higher CEC than the topsoil horizon. Near BC surfaces, higher ratios of Ca/C and K/C in subsoil than topsoil horizons reinforce the observation that BC in subsoil horizons had a higher capacity in binding cations and creating CEC than in the topsoil horizon. Conclusions: Oxidation of BC is suggested to be more efficient and important for creating CEC than the adsorption of non-BC onto BC surfaces, thus identified as being key for BC surface functionality and nutrient retention in Amazon Anthrosols.

Fine structural analysis of the stinger in venom apparatus of the scorpion Euscorpius mingrelicus (Scorpiones: Euscorpiidae)

In this study, the morphology, histology and fine structure of the stinger, a part of the venom apparatus of Euscorpius mingrelicus (Kessler, 1874) (Scorpiones: Euscorpiidae) were studied by light microscopy and transmission electron microscopy (TEM). The stinger, located at the end section of the telson, is sickle-shaped. The venom is ejected through a pair of venom pores on its subterminal portion. Both venom ducts extend along the stinger without contact with each other since they are separated by connective tissue cells. The stinger cuticle is composed of two layers. Additionally, there are many pore canals and some hemolymph vessels in the cuticle. This work constitutes the first histological and fine structure study on Euscorpius mingrelicus stinger.(AU)

Vas deferens surface epithelium of Agouti paca: fine structural features / Epitelio del conducto deferente de Agouti paca: observaciones de estructura fina

The surface epithelium of the vas deferens of Agouti paca, a wild and large South American rodent, was basically formed by principal and basal cells being only the principal cells related to endocytosis processes and also secretion taking base on their cytoplasmic ultrastructural features. Principal cell of vas deferens epithelium were characterized mainly by presence of vesicles with several shapes, sizes and internalized content at their apical cytoplasm occurring smaller pits and pale small vesicles seen next to the apical brush border of microvillus. Moreover, coated vesicles, smooth surface vesicles and great vesicles; multivesicular bodies, endosomes and lysosomes were seen. Presence of an apocrine secretory apparatus was also viewed, showing apical cytoplasmic expansions protruding into the vas deferens luminal compartment. The basal flattened cells, without luminal surface contact, occurred next to the basement membrane of the ductus, and did no exhibit special ultrastructural features.

El epitelio que recubre la luz del conducto deferente de la laca (Agouti paca), un roedor silvestre de Sudamérica, está formado por células principales (P) y básales (B), en donde las células principales están asociadas a los procesos de endocitosis y secreción, teniendo una base en su característica ultraestructural citoplasmática. Las células principales de los vasos deferentes del epitelio se caracteriza principalmente por la presencia de vesículas con variadas formas, tamaños y contenido interior en su citoplasma apical produciendo pequeñas invaginaciones y pequeñas vesículas pálidas ubicadas continuas al borde en cepillo de las microveilosidades apicales. Además, fueron observados, vesículas de superficie lisa y vesículas de gran tamaño; órganos multivesiculares, endosomas y lisosomas. También se observó la presencia de un aparato secretor apocrino, con expansiones citoplasmáticas apicales que se protruyen en el compartimiento luminar del conducto deferente. Células básales aplanadas, sin contacto con la superficie luminal, se encuentran junto a la membrana basal del conducto, las que no presentan características ultraestructurales especiales.

Fine Structure of Goblet Cell Regeneration on Experimental Colitis Induced by Dextran Sulfate Sodium / 대한해부학회지

Ulcerative colitis is recognized as important causes of gastrointestinal diseases in children and adults. I observed the fine structural changes of goblet cell regeneration after experimental ulcerative colitis induced by dextran sulfate sodium (DSS) in rats. Experimental colitis was induced with 5% DSS in the drinking water for 5 days, and the healing groups were fed with pure water for 7 days thereafter. In the early stage of goblet cell regeneration (repair 3 days group), granular endoplasmic reticulums were developed around the nucleus, and some mucigen granules were observed around the nucleus. In the middle stage of goblet cell regeneration (repair 5 days group), Golgi complexes were well developed in the upper region to the nucleus, and many mucous granules were observed. In the matured goblet cell regeneration (repair 7 days group), many mucous granules appeared in the upper region of the cell, and cell organelles were located in the base and periphery of the cell. These results suggest that the goblet cell was completely reconstructed within 7 days after ulcerative colitis.

Effect of beta-amyloid Peptide on Fine Structure of Cardiac Myocytes in Culture / 대한해부학회지

Several predetermined concentrations of beta-amyloid peptide, (betaA) were administered to the rat cardiac myocyte cultures for three days to determine the effects of betaA. Stainings with congo red and crystal violet were used to evaluate the deposition of betaA in the cardiac myocytes and MTT assay was used to elucidate the cytotoxic effects of betaA by anlaysis of cell viability. Beating rates and morphological changes were investigated with inverted microscope and TEM was used to study the fine structures. Administration of 0.5 microgram/ml of betaA to cardiac myocytes induced the reduction of beating rate, however, it did neither affect the viability nor fine structures. No significant differences in cell viability or fine structures were noted in the experimental groups which were exposed to 5 microgram/ml or higher concentration of betaA. Deposition of betaA was confirmed in the cytoplasm of betaA treated cardiac myocytes with congo red and crystal violet amyloid stains. The viability of cardiac myocytes exposed to betaA was found to be reduced significantly (19%) compared to control cultures with the MTT assay. Cardiac myocytes treated with betaA presented a reduced cytoplasmic area that appeared very condensed under inverted microscope. Mitochondrial abnormalities in betaA treated cardiac myocytes included their significant enlargement, vacuolization, disorganization or paucity of cristae, paracrystalline inclusion, and accumulation of amorphous material in mitochondrial space. Mitochondrial abnormalities were present sometimes in betaA treated cardiac myocytes without disorganization of myofibils or degeneration of other cell organelles. To understand the mechanism involved in amyloid deposit and its role in pathogenesis of the diseases such as Alzheimer and inclusion body myositis (IBM), a need for in vitro model is imperative. This model of betaA treated cultured cardiac myocytes represent a amyloidosis model, and it offers several advantages for future studies of betaA to help elucidate the pathogenesis of amyloid diseases. For example, cardiac myocytes can be easily accessible, and since cardiac myocytes can be cultured for quite a long time, it is possible to study morphological and physiological changes consequent to amyloid deposits.

Effects of Nocodazole on Fine Structures in Co-cultured Vascular Endothelial Cells and Cancer Cell Lines / 대한해부학회지

Endothelial cells were isolated from the aortic intima of Sprague-Dawley species, rat. These cells and each cancer cell line (HeLa, Hep G2, A549, L929 and NIH/3T3 cells) were co-cultivated in alpha-MEM with 3 micrometer or 30 micrometer nocodazole. To investigate the influences induced by nocodazole, the morphological changes were observed under inverted microscope and transmission electron microscope, the amounts of fibronectin produced by vascular endothelial cells and cancer cell lines and the activities of nitric oxide synthetase synthesized mainly by endothelial cells were analyzed in the aspects associated with fine structural changes. The vascular endothelial cells of control group at the 1st, 2nd and 3rd days extended the cell processes, which contacted with cells from all cell lines investigated, but the endothelial cells of nocodazole-treated groups didn't possess the processes. All cell lines in nocodazole-treated groups had a large number of micronucleated cells, but endothelial cells didn't show micronuclei. Compared with control group, the endothelial cells of nocodazole-treated groups at the 1st, 2nd and 3rd days showed the decrease of amounts of fibronectin because of the increase of heterochromatin area. The amounts of fibronectin increased in all cell lines of nocodazole-treated groups at the 2nd and 3rd days whereas the nuclear folding or the dilatation/numerical increase of rough endoplasmic reticulum didn't appear. The activities of nitric oxide synthetase heightened in endothelial cells of nocodazole-treated groups, and therefore the considerable changes in fine structures such as vesicles, lysosomes, liposomes, pyknosis and cell lysis occurred even though the extent of changes differed among the cell lines. Taken together, the materials such as fibronectin or nitric oxide synthetase produced by endothelial cells directly or indirectly acted on cancer cells, and the amounts of fibronectin and the vesicles, lysosomes, liposomes and cell lysis seemed to be much more increased or enforced. Therefore, co-culture system seemed to work better for the investigation of actions of nocodazole and the role of endothelial cells in cancer cells research. Also, the co-culture system was closer to the in vivo state and more favorable in studies for proliferation or metastasis of cancer cells.

Fine Structure and Albumin Gene Expression in Intrasplenically Transplanted Hepatocytes / 대한내과학회지

BACKGROUND: The morphological characteristics of hepatocytes transplanted into the spleen have been studied. However few attempts has been made to determine the expression of genes in intrasplenically transplanted hepatocytes. The aim of this study was to explore whether the pattern of expression of albumin gene in intrasplenically transplanted hepatocytes is similar to that in adult liver, resulting in the long-term expression of this hepatocyte-specific gene. METHODS: Hepatocytes isolated from liver of syngeneic Fischer 344 rats and transplanted into the spleen of rats from the same strain survived for 12 months in the absence of immunosuppressive drugs. Microscopic examination of intrasplenic hepatocytes and Northern blotting for albumin gene expression of RNA extracted from liver and spleen was performed. RESULTS: Microscopy demonstrated that hepatocytes attached themselves only in the red pulp of the spleen and isolated hepatocytes preserved the fine structures characteristic of normal hepatic parenchymal cells. Throughout the 12 months period, intrasplenically transplanted hepatocytes expressed albumin mRNA. CONCLUSIONS: Intrasplenically transplanted hepatocytes represent a unique in vivo system of extrahepatic maintenance of hepatocytes. This novel transplantation system could be used to investigate hepatocyte engraft, proliferation and gene expression.

EFFECT OF CLONIDINE ON CAT ARRHYTHMIAS OCCURRED DURING MYOCARDIAL ISCHEMIA / 中国药理学通报

Study was carried on pentobarbital anesthetized cats to investi-gate the effect of clonidine on arrhythmias induced by coronary occlusion. Clonidine 15???g/kg iv 15min prior to ligation of left anterior descending coronary artery significantly reduced the frequenecy of arrhythmias: the ventricular premature bats ( phase Ia, VPB from 80% in controls to 20%,P

Genetic analysis of a Minute mutation in the distal region of the second chromosome of Drosophila melanogaster.

Genetic organization of a proximal region of the second chromosome in Drosophila melanogaster has been analysed by saturation mutagenesis. Seven alleles were uncovered in this region in addition to the one previously known. Besides this, quite a few mutations were isolated that non-complemented more than one group of lethals and looked very much like deletions of varying extent. Except one, all the lethals complemented M(2)z.

Abnormalities in the fine structure of the spermatids of rats injected with cadmium.

The degenerative changes in the spermatids as measured by changes in fine structure abnormalities increased with time following injection of Cd2+ into rat testis. The spermatids in the twelve hours group appear as peculiarly club shaped and elongated structures with one or two small but perceptible vacuoles. The subacrosomal area and the space between the nucleus and the middle piece are seen abnormally dilated. In the 30 day group, the central filaments are the most susceptible unit of 9+2 axoneme complex. The plasma membrane, the cytoplasmic matrix, the mitochondria of the middle piece and the fibrous sheath appear shrunken, discontinuous and degenerative.

FINE STRUCTURE OF FERTILIZATION AND CYTOPLASMIC COMPONENTS OF THE PRONUCLEAR EMBRYOS IN THE GOAT / 解剖学报

Light and electron microscopic observations revealed that most of the embryos collected 15-16 hours after fertilization were at the pronuclear stage. Many supernumerary spermatozoa were found on the surface and in the outer zone of the zona pellucida, but none of them got into the inner zone of the zona or the perivitelline space. Some spermatozoa on the zona surface were observed in acrosome reaction stage, and those penetrated into the zona always left some acrosome reaction vesicles behind on the surface of the zona. The fertilized ovum eliminated almost all of its cortical granules and where there were some granules left, in the area that the plasma membrane had fewer microvilli. The cortical cytoplasm of the pronuclear zygote was populated with clustered hooded mitochondria, SER vesicles, yolk vacuoles and lipid droplets. Directly surrounding the pronucleus were a variety of organelles including welldeveloped Golgi complex, SER, mitochondria and annulate lamellae. The significance of these morphological changes of the fertilized ovum was discussed.