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| 1 | Stemflow, throughfall and channelization of stemflow by roots in three Chihuahuan desert shrubs显示文摘 | Ernesto Martinez-Meza Walter G. Whitford | 1996 | Journal of Arid Environments1996，，3： | 3 |
| 2 | Stemflow contribution to the ‘fertile island’ effect in creosotebush, Larrea tridentata显示文摘 | Walter G Whitford John Anderson Patricia M Rice | 1997 | Journal of Arid Environments1997，，3： | 2 |
| 3 | Ex vivo testing of intact eye globes under inflation conditions to determine regional variation of mechanical stiffness显示文摘Background:The eye globe exhibits significant regional variation of mechanical behaviour.The aim of this present study is to develop a new experimental technique for testing intact eye globes in a form that is representative of in vivo conditions,and therefore suitable for determining the material properties of the complete outer ocular tunic.Methods:A test rig has been developed to provide closed-loop control of either applied intra-ocular pressure or resulting apical displacement;measurement of displacements across the external surface of the eye globe using high-resolution digital cameras and digital image correlation software;prevention of rigid-body motion and protection of the ocular surface from environmental drying.The method has been demonstrated on one human and one porcine eye globe,which were cyclically loaded.Finite element models based on specimen specific tomography,free from rotational symmetry,were used along with experimental pressure-displacement data in an inverse analysis process to derive the mechanical properties of tissue in different regions of the eye’s outer tunic.Results:The test method enabled monitoring of mechanical response to intraocular pressure variation across the surface of the eye globe.For the two eyes tested,the method showed a gradual change in the sclera’s stiffness from a maximum at the limbus to a minimum at the posterior pole,while in the cornea the stiffness was highest at the centre and lowest in the peripheral zone.Further,for both the sclera and cornea,the load–displacement behaviour did not vary significantly between loading cycles.Conclusions:The first methodology capable of mechanically testing intact eye globes,with applied loads and boundary conditions that closely represent in vivo conditions is introduced.The method enables determination of the regional variation in mechanical behaviour across the ocular surface. | Charles Whitford Akram Joda Steve Jones Fangjun Bao Paolo Rama Ahmed Elsheikh | 2016 | Eye and Vision2016，3，1： | 2 |
| 4 | 角膜生物力学检测方法介绍显示文摘力学问题贯穿于生物体的整个生命过程,对生物体中的力学问题进行定量分析,产生了生物学和物理学的交叉学科——生物力学;其研究重点是生理学、医学有关的力学问题.随着医疗检查诊断技术的发展,人们逐渐认识到眼生物力学性能的重要性.角膜生物力学性能测量在角膜疾病诊断、角膜屈光手术效果预测及眼内压测量等方面都具有非常重要的意义.角膜组织主要由致密交错的胶原纤维束和细胞外基质组成,其生物力学特征颇为复杂,表现为非线弹性、各向异性、黏弹性、区域差异性和年龄相关性等特征.生物力学性能测量的关键是找寻描述生物组织力学特性的本构方程,方程内包含的参量为本构参量,包括应力、应变和弹性模量等.根据测量时生物材料初始状态的差异,角膜生物力学性能参数的测量方法可分为离体和在体测量2种.虽然在体测量具有更为广阔的临床应用前景,然而当前在体测量技术并不成熟.临床常用仪器ORA和Corvis无法提供本构参量,尚不能作为眼生物学性能测量的标准实验手段.笔者就目前国际上常见几种离体测量技术的原理及发展做了详细介绍,以方便相关研究者更好地进行选择,这其中包括:轴向拉伸试验、基于薄壳理论的简单离体角膜膨胀试验、基于逆向建模技术的离体角膜膨胀试验和同样基于逆向建模技术的离体全眼球膨胀试验.将切成条状的角膜试件固定于材料试验机进行单向或双向拉伸,获取本构参量,是为轴向拉伸试验.最早用于角膜生物力学性能的测量,此方法设备简单,容易操作,但对角膜的生理结构破坏较大,测量值存在不小的误差.基于薄壳理论的简单离体角膜膨胀试验:将完整分离的角膜试件固定于填充有液体的前房模拟装置,模拟眼内压对角膜后表面施压并实时记录角膜形变;根据薄壳理论推导公式计算得到角膜组织的本构关系方程.离体角膜膨胀试验保持了角膜组织结构的完整性和提供更接近于角膜生理状态的施力方式,但仍存在破坏角巩膜连续解剖结构、机械固定方式导致应力集中等缺点.因薄壳理论的球形角膜结构和均质性生物力学性能假设限制了膨胀试验结果的精确性,通过构建具有个性化几何特征的角膜有限元生物力学模型,模拟角膜在眼内压力作用下的形变过程,将膨胀试验测量所得眼内压和角膜形变关系曲线作为目标曲线,不断调整本构方程系数使得模拟的角膜形变曲线和目标曲线逐渐逼近,反复迭代运算得到角膜组织本构参量的最优化结果,称为基于逆向建模技术的离体角膜嘭胀试验,具有较好的试验测量精度和可重复性.离体全眼球膨胀试验延续了角巩膜完整的曲面形状和采取接近眼球生理的施力方式,是相对最接近角膜生理状态的测量方法,但该试验也存在设备制作复杂、操作繁琐等缺点.如能在试验过程中提供接近生理状态的眼球支撑方式,解决角巩膜随眼内压力变化过程形变数据的准确提取等技术难题,有望实现对角巩膜组织区域差异性、各向异性及黏弹性等生物力学特征的一体化定量测量分析,具有非常广阔的应用前景. | Charles Whitford Ahmed Elsheikh 包芳军(整理翻译) | 2014 | 中华眼视光学与视觉科学杂志2014，16，5： | 2 |
| 5 | Microbial diversity and activity of disturbed soil in the northern Chihuahuan Desert显示文摘 | X. Liu William C. Lindemann Walter G. Whitford Robert L. Steiner | 2000 | Biology and Fertility of Soils2000，，3： | 2 |
| 6 | In vivo study of corneal responses to increased intraocular pressure loading显示文摘Background:The cornea is responsible for two-thirds of the eye's refractive power which is a function of the shape and refractive index.The aim of this present study is to examine human eyes in vivo for corneal shape changes in response to short-term elevation in intraocular pressure.Methods:Videokeratographic and tonometric assessments at baseline were compared with the same assessments when intraocular pressure was elevated to approximately double(199±22%)the baseline levels using ophthalmodynamometer applanation of the sclera.Composite maps of the cornea and limbus were created by combining topographical assessments for central,nasal,temporal,inferior and superior fixation.Numerical finiteelement simulations were custom built for each subject and the stiffness distribution across corneal surface modified to achieve matches between simulated and experimental data.Results:The stiffness distributions required to achieve simulation-experimental matches showed a consistent trend with the 2.5 mm annulus bounded by the limbus showing a mean stiffness reduction of 47.3±10.8%compared with the central cornea(P=0.001).Conclusions:Corneal structure appears to provide the central cornea with a greater stiffness compared with the peripheral cornea and associated greater tolerance to elevation in intraocular pressure,consistent with the need for stable corneal refraction and vision.The method adopted to examine corneal biomechanical performance in vivo may have applications in additional studies. | Ahmed Elsheikh Charles W.McMonnies Charles Whitford Gavin C.Boneham | 2015 | Eye and Vision2015，2，1： | 2 |
| 7 | Enamel uptake and patient exposure to fluoride:comparison of APF gal and foam显示文摘 | Whitford GM Adair SM Hanes CMM | 1995 | American Academy of Pediatric dentistry1995，17，3： | 1 |
| 8 | Using resistance and resilience measurements for 'fitness' tests in ecosystem health显示文摘 | Rapport D J Desoyza A G | 1999 | Journal of environmental management1999，57，： | 1 |
| 9 | Induction of tumorigen-esis and metastasis by the murine orthologue of tumor protein D52 显示文摘 | Lewis J D Payton L A Whitford J G | 2007 | Mol Cancer Res2007，5，2： | 1 |
| 10 | Staging of the axilla in brest cancer:an accurate in vivo assessment using Positron emission tomography with 2-(fluorine-18)-fluoro-2 -deoxy-D-glucose显示文摘 | SMITH I C OGASTON K N WHITFORD P | 1998 | Ann Surg1998，220，： | 1 |
| 11 | Effects of pocket gophers on desert soils and vegetation显示文摘 | Graham I.H Kerley Walter G Whitford Fenton R Kay | 2003 | Journal of Arid Environments2003，，2： | 1 |
| 12 | Classifying Bankrupt Firms with Funds Flow Components显示文摘 | Gentry J A Newbold P Whitford D T | 1985 | Journal of Accounting Research1985，23，1： | 1 |
| 13 | Effects of water, nitrogen and sulfur amendments on cove,density and size of Chihuahuan desert ephemerals显示文摘 | LUDWIG j A WHITFORD W G CORNEIffUS J M | 1989 | J Arid Environ1989，16，： | 1 |
| 14 | 'City form and natural process' - indicators for the ecological performance of urban areas and their application to Merseyside, UK 显示文摘 | Whitford V Ennos A R Handley J F | 2001 | Landscape and Urban Planning2001，57，2： | 1 |
| 15 | Diversity of arthropod responses to host-plant water stress in a desert ecosystem in southern New Mexico 显示文摘 | Schowalter T D Lightfoot D C Whitford W G | 1999 | American Midland Naturalist1999，142，： | 1 |
| 16 | Translational Data from Adeno-Associated Virus-Mediated Gene Therapy of Hemophilia B in Dogs显示文摘 | Nichols TC Whitford MH Arruda VR | 2015 | Hum Gene Ther Clin Dev2015，26，1： | 1 |
| 17 | Induction of tumorigen- esis and metastasis by the murine orthologue of tumor protein D52 显示文摘 | Lewis J D Payton L A Whitford J G | 2007 | Mol Cancer Res2007，5，2： | 1 |
| 18 | Stem flow cuntribution to the 'fertile island' effect in crensotebush,Larrea tridentate显示文摘 | WHITFORD W G ANDERSON J RICE E M | 1997 | Journal of Arid Environments1997，35，： | 1 |
| 19 | Using resistance and resilience measurements for ' fitness' tests in ecosystem health显示文摘 | Whitford W G Rapport D J deSoyza | 1999 | Journal of Environmental Management1999，57，1： | 1 |
| 20 | Factors affecting annual plants assemblages on banner-tailed kangaroo rat mounds显示文摘 | Mun H Whitford W G | 1990 | Journal of Arid Environments1990，18，： | 1 |
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