检索结果-南通市图书馆

Simulation of Human Phonation with Vocal Nodules

American Journal of Computational Mathematics 2011年第3期1卷 189-201页

作者： shinji deguchi Yuki Kawahara 不详

The geometric and biomechanical properties of the larynx strongly influence voice quality and efficiency. A physical understanding of phonation natures in pathological conditions is important for predictions of how voice disorders can be treated using therapy and rehabilitation. Here, we present a continuum-based numerical model of phonation that considers complex fluid-structure interactions occurring in the airway. This model considers a three-dimensional geometry of vocal folds, muscle contractions, and viscoelastic properties to provide a realistic framework of phonation. The vocal fold motion is coupled to an unsteady compressible respiratory flow, allowing numerical simulations of normal and diseased phonations to derive clear relationships between actual laryngeal structures and model parameters such as muscle activity. As a pilot analysis of diseased phonation, we model vocal nodules, the mass lesions that can appear bilaterally on both sides of the vocal folds. Comparison of simulations with and without the nodules demonstrates how the lesions affect vocal fold motion, consequently restricting voice quality. Furthermore, we found that the minimum lung pressure required for voice production increases as nodules move closer to the center of the vocal fold. Thus, simulations using the developed model may provide essential insight into complex phonation phenomena and further elucidate the etiologic mechanisms of voice disorders.

关键词： Aerodynamics Flow–Structure Interaction Self-Excited Oscillation Phonation Vocal Fold Larynx Vocal Tract Speech Production Voice Production Vocal Nodules Vocal Cord Polyp Voice Disorder

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Measuring surface geometry of adherent cells using oblique transillumination

引用

Advances in Bioscience and Biotechnology 2011年第5期2卷 359-363页

作者： shinji deguchi Haruhisa Bamba 不详

We present a new technique for estimating cell surface geometry. A dish supporting adherent cells is observed using oblique transillumination and rotated in the horizontal plane using a stepping motor. The stage rotation-dependent movements of the start and end points of a shadow formed behind the illuminated cells uniquely determine the relative height differences between points along the cell surface. Thus, using custom-made apparatuses and living endothelial cells, we demonstrate that the combination of a rotating stage and oblique lighting allows for the evaluation of three-dimensional surface geometry of adherent cells. As compared to confocal microscopy and atomic force microscopy, which are commonly used for measuring cell surface geometry, this approach can be performed rapidly and is especially suitable for the observation of unstained cells over a large surface covering multiple cells at a time.

关键词： 3D Cell Morphology Oblique Illumination Rotating Stage Microscopy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Producing single microbubbles with controlled size using microfiber

引用

Advances in Bioscience and Biotechnology 2011年第5期2卷 385-390页

作者： shinji deguchi Satoshi Takahashi Syuhei Tanimura Hidenori Hiraki 不详

Microbubble-mediated pore formation in sonoporation includes a combination of complex processes such as collision or coalescence of translating or collapsing microbubbles with vascular cells. Although understanding the pore formation mechanisms may improve drug delivery efficiency, their details are still poorly understood. In the present study, we describe an experimental model that produces single air bubbles with controllable size. A carbon microfiber in liquids is illuminated by an infrared laser to produce individual bubbles having size comparable to that of the microfiber. The microbubbles can be physically isolated from the fiber for placing at arbitrary positions in the liquids. The lifetime of the bubbles is several tens of minutes depending on the intensity of the laser used. The preparation of the controllable air bubbles may be useful in future investigations of ultrasound-mediated microbubble–cell interactions.

关键词： Microbubble Nanobubble Carbon Fiber Glass Fiber Infrared Laser Drug Delivery System

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：