942 resultados para Vocal nodules


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Symbiosis between Frankia,VA mycorrhizal fungi and Hippophae rhamnoides L.was studied in lab.The characteristic structures-arbuscules of VAM and nodules were confirmed in the root of H.rhamnoides L.,which was inoculated with VAMF and Frankia in pure artificial culture.Evaluated by the stimulation on the growth of the host plant,VAH is a better associated fungi and HR16 is a better Frankia for Hippophae rhamnoides L.

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Authigenic carbonates were sampled in methane-enriched piston core sediments collected from gas venting sites on the western continental slope of the Ulleung Basin, East Sea of Korea. Multidisciplinary investigations on these carbonates, including the scanning electronic microscope (SEM) observations and mineralogical-geochemical compositions, were carried out to identify the carbon and oxygen sources and the forming mechanism of these carbonates. The authigenic carbonates from the study area correspond to semi-consolidated, compact concretions or nodules ranging from 2 to 9 cm in size. X-ray diffraction and electron microprobe analyses showed that most of the sampled carbonate concretions were composed of almost purely authigenic high-Mg calcite (10.7-14.3 mol% MgCO3). Characteristically, microbial structures such as filaments and rods, which were probably associated with the authigenic minerals, were abundantly observed within the carbonate matrix. The carbonates were strongly depleted in delta C-13 (-33.85 parts per thousand to -39.53 parts per thousand Peedee Belemnite (PDB)) and were enriched in delta O-18 (5.16-5.60 parts per thousand PDB), indicating that the primary source of carbon is mainly derived from the anaerobic oxidation of methane. Such methane probably originated from the destabilization of the underlying gas hydrates as strongly supporting from the enriched O-18 levels. Furthermore, the strongly depleted delta C-13 values (-60.7 parts per thousand to -61.6 parts per thousand PDB) of the sediment void gases demonstrate that the majority of the gas venting at the Ulleung Basin is microbial methane by CO2 reduction. This study provides another example for the formation mechanism of methane-derived authigenic carbonates associated with gas-hydrate decomposition in gas-seeping pockmark environments. (c) 2009 Elsevier Ltd. All rights reserved.

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本文以东菲律宾海沉积物表层新型深水铁锰结壳、铁锰结核及结壳下伏沉积物为研究对象,通过对其显微结构构造、矿物组成、元素组分的分析、元素赋存状态的系统研究、铀系和10Be同位素年代学测试,结合结壳(核)成矿背景和控矿要素分析,研究和恢复了研究区深水铁锰结壳(核)的成因与古海洋环境响应。这一结果填补了深海沉积物表层新型深水铁锰结壳系统研究的空白,深化了对铁锰结壳(核)分布规律、成因和形成过程及其古海洋环境记录作用的认识,充实了海底金属成矿理论,为铁锰结壳(核)的勘探与开采提供了理论基础和支持,同时也为研究区晚中新世以来一直不甚明了的构造演化提供了新的研究载体和资料。 通过研究,得出如下结论:(1)研究区铁锰结壳(核)的成矿背景主要受控于南极底流强弱及物源供给的变化;(2)证实铁锰结壳(核)主要为水成成因,同时其物质组成也受一定程度的火山和陆源物质的影响;结壳(核)自形成以来没有遭受到明显的磷酸盐化等成岩后期改造和元素再迁移,具有重要的古海洋学意义;(3)通过新型铁锰结壳及下伏沉积物元素赋存状态的研究,认为生物作用对研究区结壳的形成并没有很大的直接影响,其物质成分主要来自于结壳中铁锰氧化物(氢氧化物)的吸附作用;(4)在控矿要素的研究中,归纳出了地质与海洋两大类结壳(核)控矿要素;(5)根据结壳成分长周期变化趋势,结合铀系和10Be测年结果,将研究区结壳的形成过程划分为三个主要阶段(5.6~2.8 Ma,2.8~2.7 Ma和2.7 Ma以来),并确定了晚中新世以来研究区南极底流的活动情况、火山和大陆来源(风尘)物质输入量的变化。

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Two marine urostylid ciliates, Holosticha hamulata n. sp. and Holosticha heterofoissneri Hu and Song, 2001, were investigated using live observation and protargol impregnation. Both species were isolated from Korean intertidal sediments of the Yellow Sea. Holosticha hamulata measures about 150 x 25 pro in vivo, and is characterized by a tripartite body shape with a narrow head, an inflated trunk, and a tail that distally projects ventrally forming a hook-like structure. It is the characteristic body shape that distinguishes H. hamulata distinctly from congeners. Holosticha hamulata differs from H. heterofoissneri, possibly the nearest relative, also by the location of the contractile vacuole (ahead of mid-body versus near posterior body third) and the configuration of the macronucleus (on average, 33 scattered nodules assuming a Y-shape versus 17 nodules that may form a U shape). The average number of the macronuclear nodules is a pronounced feature showing great consistency in populations of each species. However, their arrangement is variable in H. heterofoissneri where the nodules are basically scattered or connected by fine fibers forming an elongate U-shape. The location of the contractile vacuole as a taxonomic feature is discussed and a dichotomous key to the species of Holosticha sensu stricto is provided.

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Two new urostylid ciliates, Metaurostylopsis songi n. sp. and Metaurostylopsis salina n. sp. and Metaurostylopsis marina (Kahl 1932) are investigated using live observation and protargol impregnation. These species were isolated in Korea from intertidal sediments, saline ponds, and coastal waters. Metaurostylopsis songi is in vivo about 120 pm x 25 mu m, has a slenderly ellipsoidal body, colorless cortical granules in rows on ventral and dorsal body sides, about 54 macronuclear nodules, 28-47 adoral membranelles, five frontal, two or three frontoterminal and six or seven transverse cirri, and 9-12 midventral cirral pairs followed posteriorly by 1-3 single cirri. In vivo M. salina is about 60 pin x 25 mu m, has a pyriform body, colorless cortical granules irregularly arranged, about 45 macronuclear nodules, 18-23 adoral membranelles, three frontal, three to five frontoterminal and two to five transverse cirri, and four or five midventral cirral pairs followed posteriorly by five to seven single cirri. Both species have three marginal cirral rows on each body side and 3 long dorsal kineties. The Korean specimens of M. marina match the Chinese population in all main features. Metaurostylopsis songi differs from M. marina by the more slender body, the number of frontal cirri (invariably five vs. four), and the arrangement of cortical granules (in rows on dorsal and ventral cortex vs. only along dorsal kinetics and anterior body margin). Metaurostylopsis salina differs from its congeners by the distinctly smaller size, the pyriform body shape, the scattered cortical granules (vs. in rows), and number of frontal cirri. It differs from M. marina also by the number of midventral cirral pairs (four or five vs. seven to 11).

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The morphology and infraciliature of a new ciliate, Metastrongylidium distichum, isolated from the Yellow Sea, are investigated using live observation and protargol impregnation. Metastrongylidium distichum is about 170 x 40 pm in vivo, clavate to elongate ellipsoidal with bluntly pointed posterior end, and has two macronuclear nodules, six distinctly large buccal and frontal cirri, three dorsal kineties and two each of spiralled ventral and marginal cirral rows. These features indicate a generic allocation in Strongylidium Sterki, 1878. However, the new ciliate has a distinct feature not recognizable in Strongylidiurn, viz., the presence of (three or four) transverse cirri. Thus, we propose a new genus Metastrongylidium for the new species, M distichum nov. gen., n. sp. Metastrongylidium belongs to the family Spirofilidae, where it differs from Mucotrichidium by the lack of postperistomial cirrus and the different frontal and ventral cirral pattern. Metastrongylidium distichum is easily distinguishable from the seemingly similar species Strongylidium californicum Kahl, 1932 by the macronuclear pattern (invariably 2 vs. many nodules). It highly resembles the poorly known species S. contortum (Gelei 1954) Borror, 1972 in the body outline and nuclear pattern, differing in the biotope, the posterior cirral pattern, and the arrangement of right marginal row.

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The morphology and infraciliature of a new ciliate, Kiitricha minuta n. sp., isolated from the Yellow Sea, were investigated using live observation and protargol impregnation. Kiitricha minuta represents a third member of the rarely known order Kiitrichida. It is unique in the subclass Hypotrichia in having many rows of small uniform cirri along the right side of the body and the dorsal kineties composed of dikinetids, most of which bear two cilia. Kiitricha minuta n. sp. is ovoid and measures about 60 x 45 mu m in vivo. It has a huge buccal cavity occupying about 80% of the body length, numerous body extrusomes, one macronucleus and two micronuclei, 27-27 adoral membranelles, 9-12 frontoventral cirral rows, a submarginal row of 7-9 cirri, 6 or 7 transverse cirri, and roughly 7-9 dorsal kineties. This new species differs distinctly from its only congener Kiitricha marina by its smaller size (60 mu m vs. 80-150 mu m), the presence of body extrusomes (vs. absent), the different macronuclear pattern (one vs. two nodules), and the lower number of frontoventral cirral rows (9-12 vs. 21-26), which terminate at the anterior two-thirds of body (vs. extend to the posterior). The new term "submarginal cirral row" is introduced to distinguish from the marginal cirral row in typical hypotrichs sensu lato. Based on our new observations and the literature, an improved diagnosis for the genus Kiitricha is provided and its phylogenetic importance is discussed.

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以大洋采矿前期的湖试为例,介绍了AUV在矿产资源调查和深海采矿中的应用。在深海采矿系统作业前期,利用AUV调查湖底的地形地貌、结核的分布与覆盖率,确定集矿机作业地点的大地坐标。在深海采矿系统作业后期,利用AUV调查集矿机在湖底的行走轨迹和压陷深度,估算回采率。

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介绍了“CR 0 1”自治水下机器人的研制背景和系统的特点 ,以及“CR 0 1”在太平洋锰结核调查中的应用情况 ,并对所获得的数据进行了分析

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This work addresses two related questions. The first question is what joint time-frequency energy representations are most appropriate for auditory signals, in particular, for speech signals in sonorant regions. The quadratic transforms of the signal are examined, a large class that includes, for example, the spectrograms and the Wigner distribution. Quasi-stationarity is not assumed, since this would neglect dynamic regions. A set of desired properties is proposed for the representation: (1) shift-invariance, (2) positivity, (3) superposition, (4) locality, and (5) smoothness. Several relations among these properties are proved: shift-invariance and positivity imply the transform is a superposition of spectrograms; positivity and superposition are equivalent conditions when the transform is real; positivity limits the simultaneous time and frequency resolution (locality) possible for the transform, defining an uncertainty relation for joint time-frequency energy representations; and locality and smoothness tradeoff by the 2-D generalization of the classical uncertainty relation. The transform that best meets these criteria is derived, which consists of two-dimensionally smoothed Wigner distributions with (possibly oriented) 2-D guassian kernels. These transforms are then related to time-frequency filtering, a method for estimating the time-varying 'transfer function' of the vocal tract, which is somewhat analogous to ceptstral filtering generalized to the time-varying case. Natural speech examples are provided. The second question addressed is how to obtain a rich, symbolic description of the phonetically relevant features in these time-frequency energy surfaces, the so-called schematic spectrogram. Time-frequency ridges, the 2-D analog of spectral peaks, are one feature that is proposed. If non-oriented kernels are used for the energy representation, then the ridge tops can be identified, with zero-crossings in the inner product of the gradient vector and the direction of greatest downward curvature. If oriented kernels are used, the method can be generalized to give better orientation selectivity (e.g., at intersecting ridges) at the cost of poorer time-frequency locality. Many speech examples are given showing the performance for some traditionally difficult cases: semi-vowels and glides, nasalized vowels, consonant-vowel transitions, female speech, and imperfect transmission channels.

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Background: the impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood.Methods: the long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels.Results: of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz.Conclusions: Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.

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Objective. To compare the voice performance of children involved in street labor with regular children using perceptual-auditory and acoustic analyses.Methods. A controlled cross-sectional study was carried out on 7- to 10-year-old children of both genders. Children from both groups lived with their families and attended school regularly; however, child labor was evident in one group and not the other. A total of 200 potentially eligible street children, assisted by the Child Labor Elimination Programme (PETI), and 400 regular children were interviewed. Those with any vocal discomfort (106, 53% and 90, 22.5%) had their voices assessed for resonance, pitch, loudness, speech rate, maximum phonation time, and other acoustic measurements.Results. A total of 106 street children (study group [SG]) and 90 regular children (control group [CG]) were evaluated. the SG group demonstrated higher oral and nasal resonance, reduced loudness, a lower pitch, and a slower speech rate than the CG. the maximum phonation time, fundamental frequency, and upper harmonics were higher in the SG than the CG. Jitter and shimmer were higher in the CG than the SG.Conclusion. Using perceptual-auditory and acoustic analyses, we determined that there were differences in voice performance between the two groups, with street children having better quality perceptual and acoustic vocal parameters than regular children. We believe that this is due to the procedures and activities performed by the Child Labor Elimination Program (PETI), which helps children to cope with their living conditions.

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Y. Zhu, S. Williams and R. Zwiggelaar, 'Computer technology in detection and staging of prostate carcinoma: a review', Medical Image Analysis 10 (2), 178-199 (2006)

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Hughes, R. (2002). 'We are not Seeking Strength for its Own Sake': The British Labour Party, West Germany and the Cold War, 1951-64. Cold War History. 3(1) pp.67-94 RAE2008

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This article discusses the way in which the Chopin Year of 1910 was celebrated in Wielkopolska. It presents a script prepared in the nineteenth century and shows similarities with celebrations of Mickiewicz and other Polish heroes and artists. Invariably used in such commemorations was a “symbolic capital” that made it easier to create an intergenerational code, thereby disseminating knowledge of national culture and history. A significant role was played in 1910 by a centenary panel, which produced “Guidelines for popular Chopin celebrations” and also many occasional, popular materials. Chopin’s induction into the national pantheon involved the use of audio material (vocal and instrumental concerts), verbal material (articles, poems, lectures and brochures) and also a visual code (anniversary window stickers, tableaux vivants or tableaux illuminés). Illuminated pictures – recommended by a catalogue of slides produced in Poznań – stimulated the imagination of the masses and served as a guide through the composer’s life and work, and their impact was enhanced by a commentary. Most of the living pictures were probably inspired by Henryk Siemiradzki’s canvas Chopin grający na fortepianie w salonie księcia Radziwiłła [Chopin playing the piano in Prince Radziwiłł’s salon] and Józef Męcina Krzesz’s painting Ostatnie akordy Chopina [Chopin’s last chords]. This combination of codes made it possible to create a model adapted to the times and to the expectations of a mass audience. The Chopin anniversary, in which admiration was inseparably intertwined with manipulation, was a pretext for strengthening the national identity.