Biyomekanik Amerikan ve Uluslararası Dernekleri gelen fon bu çalışma için verilmiştir.

<ol>
	<li>Chandler, R. F., Clauser, C. E., McConville, J. T., Reynolds, H. M., Young, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+the+inertial+properties+of+the+human+body.">Investigation of the inertial properties of the human body.</a> Pamphlets DOT HS-801 430 and AMRL. , (1975).</li><li>Clauser, C. E., McConville, J. T., Young, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Weight, Volume, and Center of Mass of Segments of the Human Body. AMRL Technical Report. , 60-70 (1969).</li><li>Dempster, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Space+requirements+of+the+seated+operator.">Space requirements of the seated operator.</a> , 55-159 (1955).</li><li>Hinrichs, R. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regression+equations+to+predict+segmental+moments+of+inertia+from+anthropometric+measurements:+an+extension+of+the+data+of+Chandler+et.">Regression equations to predict segmental moments of inertia from anthropometric measurements: an extension of the data of Chandler et.</a> J Biomech. 18, 621-624 (1985).</li><li>Hinrichs, R. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adjustments+to+the+segment+center+of+mass+proportions+of+Clauser+et+al.">Adjustments to the segment center of mass proportions of Clauser et al.</a> J Biomech. 23, 949-951 (1990).</li><li>Hanavan Jr, E. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mathematical+model+of+the+human+body+Amrl-Tr-64-102.">A mathematical model of the human body Amrl-Tr-64-102.</a> AMRL Technical Report. 18, 1-149 (1964).</li><li>Hatze, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mathematical+model+for+the+computational+determination+of+parameter+values+of+anthropomorphic+segments.">A mathematical model for the computational determination of parameter values of anthropomorphic segments.</a> J Biomech. 13, 833-843 (1980).</li><li>Leva, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adjustments+to+Zatsiorsky-Seluyanov's+segment+inertia+parameters.">Adjustments to Zatsiorsky-Seluyanov's segment inertia parameters.</a> J Biomech. 29, 1223-1230 (1996).</li><li>Durkin, J. L., Dowling, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+body+segment+parameter+differences+between+four+human+populations+and+the+estimation+errors+of+four+popular+mathematical+models.">Analysis of body segment parameter differences between four human populations and the estimation errors of four popular mathematical models.</a> J Biomech Eng. 125, 515-522 (2003).</li><li>Durkin, J. L., Dowling, J. J., Andrews, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+measurement+of+body+segment+inertial+parameters+using+dual+energy+X-ray+absorptiometry.">The measurement of body segment inertial parameters using dual energy X-ray absorptiometry.</a> J Biomech. 35, 1575-1580 (2002).</li><li>Jensen, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimation+of+the+biomechanical+properties+of+three+body+types+using+a+photogrammetric+method.">Estimation of the biomechanical properties of three body types using a photogrammetric method.</a> J Biomech. 11, 349-358 (1978).</li><li>Martin, P. E., Mungiole, M., Marzke, M. W., Longhill, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+magnetic+resonance+imaging+for+measuring+segment+inertial+properties.">The use of magnetic resonance imaging for measuring segment inertial properties.</a> J Biomech. 22, 367-376 (1989).</li><li>Mungiole, M., Martin, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimating+segment+inertial+properties:+comparison+of+magnetic+resonance+imaging+with+existing+methods.">Estimating segment inertial properties: comparison of magnetic resonance imaging with existing methods.</a> J Biomech. 23, 1039-1046 (1990).</li><li>Zatsiorsky, V. M., Seluyanov, V. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mass+and+inertia+characteristics+of+the+main+segments+of+the+human+body.">The mass and inertia characteristics of the main segments of the human body.</a> Biomechanics VIII-B. , 1152-1159 (1983).</li><li>Zatsiorsky, V. M., Seluyanov, V. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomechanics+IX-B.">Biomechanics IX-B.</a> Human Kinetics. , (1985).</li><li>Challis, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+of+the+Estimation+of+Human+Limb+Inertial+Parameters.">Precision of the Estimation of Human Limb Inertial Parameters.</a> Journal of Applied Biomechanics. 15, 418-428 (1999).</li><li>Challis, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+of+Human+Limb+Moment+of+Inertia+Estimations+and+Their+Influence+on+Resultant+Joint+Moments.">Accuracy of Human Limb Moment of Inertia Estimations and Their Influence on Resultant Joint Moments.</a> Journal of Applied Biomechanics. 12, 517-530 (1996).</li><li>Challis, J. H., Kerwin, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+the+uncertainties+in+resultant+joint+moments+computed+in+a+dynamic+activity.">Quantification of the uncertainties in resultant joint moments computed in a dynamic activity.</a> J Sports Sci. 14, 219-231 (1996).</li><li>Hunter, J. P., Marshall, R. N., McNair, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Segment-interaction+analysis+of+the+stance+limb+in+sprint+running.">Segment-interaction analysis of the stance limb in sprint running.</a> J Biomech. 37, 1439-1446 (2004).</li><li>Lin-Chan, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+added+prosthetic+mass+on+physiologic+responses+and+stride+frequency+during+multiple+speeds+of+walking+in+persons+with+transtibial+amputation.">The effects of added prosthetic mass on physiologic responses and stride frequency during multiple speeds of walking in persons with transtibial amputation.</a> Arch Phys Med Rehabil. 84, 1865-1871 (2003).</li><li>Mattes, S. J., Martin, P. E., Royer, T. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Walking+symmetry+and+energy+cost+in+persons+with+unilateral+transtibial+amputations:+matching+prosthetic+and+intact+limb+inertial+properties.">Walking symmetry and energy cost in persons with unilateral transtibial amputations: matching prosthetic and intact limb inertial properties.</a> Arch Phys Med Rehabil. 81, 561-568 (2000).</li><li>Smith, J. D., Martin, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Short+and+longer+term+changes+in+amputee+walking+patterns+due+to+increased+prosthesis+inertia.">Short and longer term changes in amputee walking patterns due to increased prosthesis inertia.</a> J Prosthet Orthot. 23, 114-123 (2011).</li><li>Smith, J. D., Martin, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+prosthetic+mass+distribution+on+metabolic+costs+and+walking+symmetry.">Effects of prosthetic mass distribution on metabolic costs and walking symmetry.</a> J Appl Biomech. 29, 317-328 (2013).</li><li>Czerniecki, J. M., Gitter, A., Munro, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Joint+moment+and+muscle+power+output+characteristics+of+below+knee+amputees+during+running:+the+influence+of+energy+storing+prosthetic+feet.">Joint moment and muscle power output characteristics of below knee amputees during running: the influence of energy storing prosthetic feet.</a> J Biomech. 24, 63-75 (1991).</li><li>Miller, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resultant+lower+extremity+joint+moments+in+below-knee+amputees+during+running+stance.">Resultant lower extremity joint moments in below-knee amputees during running stance.</a> J Biomech. 20, 529-541 (1987).</li><li>Vanicek, N., Strike, S., McNaughton, L., Polman, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gait+patterns+in+transtibial+amputee+fallers+vs.+non-fallers:+Biomechanical+differences+during+level+walking.">Gait patterns in transtibial amputee fallers vs. non-fallers: Biomechanical differences during level walking.</a> Gait &amp; Posture. 29, 415-420 (2009).</li><li>Royer, T., Koenig, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Joint+loading+and+bone+mineral+density+in+persons+with+unilateral,+trans-tibial+amputation.">Joint loading and bone mineral density in persons with unilateral, trans-tibial amputation.</a> Clin Biomech. 20, 1119-1125 (2005).</li><li>Underwood, H. A., Tokuno, C. D., Eng, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+two+prosthetic+feet+on+the+multi-joint+and+multi-plane+kinetic+gait+compensations+in+individuals+with+a+unilateral+trans-tibial+amputation.">A comparison of two prosthetic feet on the multi-joint and multi-plane kinetic gait compensations in individuals with a unilateral trans-tibial amputation.</a> Clin Biomech. 19, 609-616 (2004).</li><li>Sjodahl, C., Jarnlo, G. B., Soderberg, B., Persson, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinematic+and+kinetic+gait+analysis+in+the+sagittal+plane+of+trans-femoral+amputees+before+and+after+special+gait+re-education.">Kinematic and kinetic gait analysis in the sagittal plane of trans-femoral amputees before and after special gait re-education.</a> Prosthet Orthot Int. 26, 101-112 (2002).</li><li>Bateni, H., Olney, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinematic+and+kinetic+variations+of+below-knee+amputee+gait.">Kinematic and kinetic variations of below-knee amputee gait.</a> Journal of Prosthetics and Orthotics. 14, 2-12 (2002).</li><li>Buckley, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomechanical+adaptations+of+transtibial+amputee+sprinting+in+athletes+using+dedicated+prostheses.">Biomechanical adaptations of transtibial amputee sprinting in athletes using dedicated prostheses.</a> Clin Biomech. 15, 352-358 (2000).</li><li>Yack, H. J., Nielsen, D. H., Shurr, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetic+patterns+during+stair+ascent+in+patients+with+transtibial+amputations+using+three+different+prostheses.">Kinetic patterns during stair ascent in patients with transtibial amputations using three different prostheses.</a> Journal of Prosthetics and Orthotics. 11, 57-62 (1999).</li></ol>

Yazarlar, hiçbir rakip mali çıkarlarını olmadığını beyan ederim.

Ampirik verilerle çalışırken hareketi sırasında çıkan eklem güçleri ve anları ölçmek için, faiz sisteminin ters dinamiği modeli gereklidir. Alt ekstremite biyomekanik için, ters dinamik modelleri genellikle, sap ayak temsil ve gibi katı cisimler uyluk. A) hareket kinematiği, b) yer reaksiyon kuvvetleri, ve c) segmenti antropometrik ve eylemsizlik özellikleri: bu modeller için giriş üç birincil kaynaklardan gelir. Hareket verileri hareket analizi sistemleri çeşitli toplanan, ancak tüm sistemleri temelde hareketi (konum, hız ve ivme) temel kinematiğini sağlamaktadır. Yer reaksiyon kuvvetleri bir kuvvet plaka ile toplanır ve ayakları üzerinde hareket eden temas kuvvetleri sağlamaktadır. Antropometri hükümdarları, esnek bantlar ve / veya kumpas kullanarak vücudun doğrudan alınan ölçülerdir. Bu antropometrik ölçümler ters dynami kullanılan vücut bölümlerinin atalet özelliklerini tahmin etmek için kullanılırcs analizleri. Atalet özellikleri segmentinde COM veya proksimal veya distal eklem aracılığıyla bir eksene bölüm göreli kütle kütle, merkezi (COM) yer ve atalet momenti (İçişleri Bakanlığı) içerir. Hareket ve yer reaksiyon kuvveti veri toplamak için kullanılan yöntemler ve ekipmanlar araştırma grupları arasında benzer, ancak vücut segmentlerinin atalet tahminleri araştırmacı bu atalet özelliklerini tahmin etmek için seçtiği yöntem bağlı araştırmacılar arasında yaygın olarak değişebilir. Tamamen bozulmamış insan vücudu segmentinin atalet özelliklerini tahmin etmek için çok çeşitli teknikler şunlardır: 1) kadavra veri 1-5, 2) matematiksel modeller (yani, geometrik modeller) 6,7, ve 3) tarama ve görüntüleme teknikleri dayalı regresyon denklemleri 8-15. Bu tekniklerin çoğu gövdesinden doğrudan ölçümleri gerektirmez, ancak bir önceki ne olursa olsun, tahmin yöntemi kullanıldı ancak şu şartla ki vücut SEG hassas gösterilmiştirBu yöntemlere dayalı ment atalet tahminler, yüksek 16&#39;dır. Ayrıca sağlam vücut segmentlerinin atalet özelliklerinin tahminlerinde hatalar 17,18 yürüyüş sırasında çıkan eklem anların büyüklükleri üzerinde minimal bir etkiye sahip olduğu gösterilmiştir. Ortak anlar zemin reaksiyon kuvvetleri, basınç yerle an kol uzunlukları ve segment kinematik 17-19 merkezi tarafından büyük ölçüde etkilenmektedir. Bu nedenle, araştırma katılımcıları, bu tahminlere küçük hatalar çalışmanın sonuçları üzerinde çok az etkiye sahip olasıdır verilen sağlam bireyler kullanırken vücut bölümlerinin atalet özelliklerini tahmin yöntemleri literatürde çapında büyük ölçüde değişiklik olması şaşırtıcı değildir. Tamamen sağlam vücut segmenti için bu atalet tahminlerin çoğu genellikle alt ekstremite amputasyonu için protezlerin atalet özelliklerini tahmin etmek için kullanılır. Modern alt ekstremite protezleri hafif malzemeler kullanılarak imal edilir resulting onlar yerine bacaklarda daha hafiftir protez uzuvlar içinde. Bu protez bacak ile sağlam bacak arasında bir atalet asimetri sonuçlanır. Tipik bir sağlam sap ve ayak altında bir diz protezi kütlesine ve kalıntı uzuv ile karşılaştırıldığında yaklaşık% 35 daha az olan ve diz ekleminin 20-23 için yaklaşık% 35 daha yakın bulunan bir ağırlık merkezi vardır. Düşük kütleli ve protez bacak daha yakın kütle dağılımı, aynı zamanda sağlam ve ayak gövdesinin kıyasla protez bacak için diz eklemine atalet nisbetle çok daha düşük bir (~% 60) an üretir. Araştırmacılar 24,25 önceden protez bacak için sağlam atalet tahminler kullanılarak ortak kinetik tahminleriniz üzerinde çok az etkiye sahip olduğunu ileri sürmüşlerdir rağmen, bu karşılaştırmalar yer reaksiyon kuvveti üretilen an hakim yürüyüş duruş fazı sırasında çıkan eklem anları odaklanmıştır ortak. Salıncak sırasında, nerede yer reaksiyon kuvvetleri, mevcut değilProtezin düşük atalet özellikleri elde edilen ortak anlar tahminleri etkilemek için daha muhtemeldir. Bazı araştırmacılar örneğin göz önüne alındığında, 26-32 protez atalet özelliklerini temsil bozulmamış bölüm atalet özelliklerini kullanan ve diğerleri protezin atalet özelliklerini tahmin etmek için seçilen yöntemlerin etkisini anlamak için önemlidir, doğrudan 21-23 tahmin protez atalet özellikleri örneğin . Protezin atalet özelliklerini ölçmek için gereken süreyi en aza indirerek tekniğin geliştirilmesi de önemli bir husustur oldu. Tüm ölçümler ölçme işleminden sonra protez yeniden düzenledi bağlantılı bir kez daha ölçüm sürelerini azaltmak ve önlemek için burada sunulan teknikte protez tamamen bozulmadan kalır. Bu nedenle, bu çalışmanın amacı, iki kat idi: 1) ab atalet özelliklerini tahmin etmek için direkt olarak kullanılabilecek bir teknik göstermekelow-diz protezi ve 2) tek taraflı, transtibial amputasyon yürüyüş sırasında eklem kinetik tahminlere sağlam uzuv atalet özelliklerini kullanarak önerilen teknik ve bunun etkilerini kontrast. Bu, sağlam sap ve ayak atalet özellikleri protez atalet özelliklerini doğrudan ölçümleri ile karşılaştırıldığında protez için atalet tahminler olarak kullanıldığı zaman ortak kinetik büyüklükleri daha büyük olduğu varsayılmıştır.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Oscillation Rack &#38; Reaction Board</td>
			<td style="width:144px;">Custom Built</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Outer cage made from 80/20 aluminum, inner cage from various thicknesses of solid of aluminum.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Laboratory scale</td>
			<td style="width:144px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">NI LabView</td>
			<td style="width:144px;">National Instruments</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Software for recording TTL pulses from infrared photocell.</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">BNC-1050</td>
			<td style="width:144px;">National Instruments</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">BNC Breakout box with direct pin connections to the data acquisition card</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">MATLAB</td>
			<td style="width:144px;">Mathworks Inc.</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Software for processing oscillation and reaction board data to predict inertial properties of prosthesis.</td>
		</tr>
	</tbody>
</table>

oscillation and reaction board techniques for estimating inertial properties of a below-knee prosthesis

Bu çalışmanın amacı, iki kat idi: 1) tam altında bir diz protezi atalet özelliklerini tahmin etmek için kullanılabilecek bir teknik göstermektedir, ve 2) sağlam uzuv atalet özellikleri kullanılarak, önerilen tekniği ve bu etkilerini kontrast tek taraflı, transtibial amputasyon yürüyüş sırasında eklem kinetik tahminleri. Bir salınım ve reaksiyon kurulu sistem valide ve bilinen geometrik katıların atalet özelliklerini ölçerken güvenilir olduğu gösterilmiştir. Protezin atalet özelliklerinin doğrudan ölçümleri sağlam bir şaft ve yürüyerek dayalı atalet tahminleri ile karşılaştırıldığında alt ekstremite ters dinamik modellenmesi kullanıldığı zaman, kalça ve diz eklem kinetik yürüyüş salınım fazında anlamlı olarak düşüktü. Duruşu sırasında eklem kinetik farklılıklar, ancak, salıncak sırasında gözlenen daha küçük. Bu nedenle, yürüyüş salınım fazı odaklanan araştırmacılar prosthes etkisini göz önündeçalışma sonuçlarına atalet özelliği tahminler olduğunu. Duruş için bizim çalışmamızda incelenen iki atalet modellerinden ya bir olasılıkla bir ters dinamik değerlendirme ile benzer sonuçlara yol açacak.

Diz protez bacak distalinde atalet özellikleri bozulmadan bacak (Tablo 1) göre daha düşüktü. Katılımcılar arasında ortalama, protez yan kütle diz boyunca enine bir eksen etrafında atalet momenti% 52 daha az olan,% 39 daha az olan, ve kütle konumun merkezine sağlam bacak için değerler ile karşılaştırıldığında diz% 24 daha yakın olmuştur. <table border="1" cellpadding="0" cellspacing="0" fo:keep-together.within-page="always" width="553"><tbody><tr><td> Konu </td><td> Bozulmamış * Ağırlık (kg) </td><td> Kütle † Artıları (kg) </td><td> Est. Kütle farkı (kg) </td><td> ‡ Iknee bozulmamış (kg · m 2) </td><td> Iknee artılarını (kg · m 2) </td><td> Diz ekleminin altında Bozulmamış CM (m) </td><td> Diz ekleminin altında Artıları CM (m) </td></tr><tr><td> A </td><td> 6.03 </td><td> 4.27 </td><td> 1.76 </td><td> 0,604 </td><td> 0.325 </td><td> 0.268 </td><td> 0.215 </td></tr><tr><td> B </td><td> 6.07 </td><td> 3.39 </td><td> 2.68 </td><td> 0.400 </td><td> 0.196 </td><td> 0.215 </td><td> 0.177 </td></tr><tr><td> C </td><td> 5.80 </td><td> 3.12 </td><td> 2.68 </td><td> 0.575 </td><td> 0,194 </td><td> 0.264 </td><td> 0.198 </td></tr><tr><td> D </td><td> 5.72 </td><td> 3.17 </td><td> 2.55 </td><td> 0.559 </td><td> 0.317 </td><td> 0.265 </td><td> 0.191 </td></tr><tr><td> D </td><td> 7.14 </td><td> 4.65 </td><td> 2.49 </td><td> 0.742 </td><td> 0.325 </td><td> 0.276 </td><td> 0.200 </td></tr><tr><td> F </td><td> 6.23 </td><td> 4.22 </td><td> 2.01 </td><td> 0.585 </td><td> 0.287 </td><td> 0.260 </td><td> 0.192 </td></tr><tr><td> Ortalama ± St </td><td> 6.17 ± 0.51 </td><td> 3.80 ± 0.66 </td><td> 2.36 ± 0.38 </td><td> 0.578 ± 0.109 </td><td> 0.274 ± 0.063 </td><td> 0.258 &amp;# 177; 0.022 </td><td> 0.196 ± 0.013 </td></tr></tbody></table> * Bozulmamış birleştirilen sağlam sap ve ayak için değerlerini belirtir. † Avantaj kombine protez ve kalıntı uzuv için değerlerini belirtir. Diz boyunca enine bir eksen etrafında atalet momenti ‡. Aşağı diz protez ve bozulmamış bacaklarda arasındaki atalet özellikleri Tablo 1.. Karşılaştırılması. Sonuç müşterek kuvvetler (Şekil 3) ve anlar bileği (Şekil 4), diz, kalça ve ters dinamik modelinde kullanılan atalet parametreler etkilendi. Protez atalet doğrudan tedbirler sağlam anatomi dayalı (regresyonları ile karşılaştırıldığında ters dinamik değerlendirmelerde kullanıldığı zaman özellikle, eklem kinetik salıncak başlatılması (~ yürüyüş döngüsünün% 65) ve salıncak sonlandırma (~ yürüyüş döngüsünün% 95) esnasında azaldı <strong&gt; Tablo 2). Etki büyüklüğü salıncak sırasında bu farklılıklar (≥ 1.0) önemsiz değildi öneririz. Bozulmamış atalet tahminleri kullanıldığı zaman ek olarak, ortak kinetik değerler protez atalet özelliklerinin doğrudan önlemler ile karşılaştırıldığında salıncak başlatılması ve sonlandırılması sırasında% 80 oranında ortalama artış. Bozulmamış bir uzuv atalet özellikleri protez yan modellemek için kullanılan Böylece, salınım sırasında protez tarafının ortak kinetik profiller daha çok yakın (bakınız Şekil 3 ve 4 &#39;e bakınız), bir sağlam ekstremitenin benziyordu. Duruş sırasında, istatistiksel farklılıklar bir dizi gözlendi. Duruşu sırasında herhangi bir fark büyük etki boyutu kalça anterioposterior çıkan eklem kuvvet (= 0.86 ES) için gözlenmiştir. Bu etki boyutu büyük ve hala duruşun bir parçası olarak kabul olsa da, bu tedbir için zirve değeri terminali duruşu (~% 52) sırasında meydana, ya da uzuv salıncak içine geçiş gibi. Diğer tüm significa için etki boyutlarıduruşu sırasında gözlenen nt farklılıklar kalça çıkan eklem reaksiyon kuvvetleri kutlanıyor bu değerlerin büyük ile küçük etkileri kabul edileceği, 0,01-0,41 arasında değişmektedir. Önemli farklılıklar duruşu sırasında bulunmuş olmasına rağmen, fark (yani, etki boyutları) büyüklüğü açısından değerlendirildiğinde bu farklılıklar, bu farklılıkların anlamlılık sorgulamaya bir yol olabilir. <img alt="Şekil 3," fo:content-width="5in" src="/files/ftp_upload/50977/50977fig3highres.jpg" width="500" /> Şekil 3. Anterioposterior (sol panel) ve dikey yönde (sağ panel) olarak ayak bileği, diz, kalça ve Sonuç ortak tepki kuvvetleri. Veri sunumu için deneklerin ortalamaları alınmıştır. Duruş fazı ayak temas yürüme döngüsünün% 0 başlar ve ayak-off ile yürüme döngüsünün yaklaşık% 60 biter. Salıncak t sonraki ayak temas edene kadar devamo yürüyüş döngüsünün% 100 aynı bacak. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/50977/50977fig3highres.jpg" target="_blank">, bu rakamın daha büyük bir versiyonunu görmek için buraya tıklayınız.</a> <img alt="Şekil 4," fo:content-width="5in" src="/files/ftp_upload/50977/50977fig4highres.jpg" width="500" /> Şekil 4. Ayak bileği, diz, kalça ve bir enine eksen (aka, mediolateral eksen) yaklaşık Sonuç ortak anlar. Veri sunumu için deneklerin ortalamaları alınmıştır. Duruş fazı ayak temas yürüme döngüsünün% 0 başlar ve ayak-off ile yürüme döngüsünün yaklaşık% 60 biter. Salıncak yürüme döngüsünün% 100 aynı bacağın sonraki ayak temas edene kadar devam eder. <img alt="Tablo 2" fo:content-width="6in" src="/files/ftp_upload/50977/50977table2.jpg" width="600" /> Tablo 2. Tepe edilen ortak reaksiyonkuvvetler ve momentler protez takımın ortak kinetik için konular ve iki atalet modelleri arasında istatistiksel karşılaştırmalar arasında ortalama Notlar:. Mean veriler ortalama (SD) olarak sunulmaktadır. % Yürüme Döngüsü sütun tepe değeri bu değişkene için meydana denekler genelinde ortalama yüzdesini gösterir. P &lt;.05 anlamlı kabul.

Watch this Scientific Journal Video about Oscillation and Reaction Board Techniques for Estimating Inertial Properties of a Below-knee Prosthesis at JoVE.com

Oscillation and Reaction Board Techniques for Estimating Inertial Properties of a Below-knee Prosthesis

Vücut segmental atalet özellikleri ters dinamik modelleme için gereklidir. Bir salınım ve reaksiyon tahta teknik, aşağıda diz protezlerin atalet özellikleri kullanılarak ölçüldü. Protez bacak ters dinamik modelinde protez atalet doğrudan ölçümleri kullanılarak çıkan eklem kuvvet ve moment düşük çaplara sonuçlandı.

Altında diz Protezi Tahmin Atalet Özellikleri için salınım ve Reaksiyon Kurulu Teknikleri

The purpose of this study was two-fold: 1) demonstrate a technique that can be used to directly estimate the inertial properties of a below-knee ...

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16.6K Görüntüleme.  University of Northern Colorado.  Vücut segmental atalet özellikleri ters dinamik modelleme için gereklidir. Bir salınım ve reaksiyon tahta teknik, aşağıda diz protezlerin atalet özellikleri kullanılarak ölçüldü. Protez bacak ters dinamik modelinde protez atalet doğrudan ölçümleri kullanılarak çıkan eklem kuvvet ve moment düşük çaplara sonuçlandı. 

Video: Oscillation and Reaction Board Techniques for Estimating Inertial Properties of a Below-knee Prosthesis

Measuring the Mechanical Properties of Living Cells Using Atomic Force Microscopy

Mechanical properties of cells and extracellular matrix (ECM) play important roles in many biological processes including stem cell differentiation, tumor formation, and wound healing. Changes in stiffness of cells and ECM are often signs of changes in cell physiology or diseases in tissues. Hence, cell stiffness is an index to evaluate the status of cell cultures. Among the multitude of methods applied to measure the stiffness of cells and tissues, micro-indentation using an Atomic Force Microscope (AFM) provides a way to reliably measure the stiffness of living cells. This method has been widely applied to characterize the micro-scale stiffness for a variety of materials ranging from metal surfaces to soft biological tissues and cells. The basic principle of this method is to indent a cell with an AFM tip of selected geometry and measure the applied force from the bending of the AFM cantilever. Fitting the force-indentation curve to the Hertz model for the corresponding tip geometry can give quantitative measurements of material stiffness. This paper demonstrates the procedure to characterize the stiffness of living cells using AFM. Key steps including the process of AFM calibration, force-curve acquisition, and data analysis using a MATLAB routine are demonstrated. Limitations of this method are also discussed.

This paper demonstrates a protocol to characterize the mechanical properties of living cells by means of microindentation using an Atomic Force Microscope (AFM).

Atomik Kuvvet Mikroskobu kullanarak Yaşam Hücrelerinin Mekanik Özellikleri Ölçme

Mechanical  properties of cells and extracellular matrix (ECM) play important roles in many  biological processes including stem cell differentiation, ...

Biyomühendislik

Engineering Platform and Experimental Protocol for Design and Evaluation of a Neurally-controlled Powered Transfemoral Prosthesis

To enable intuitive operation of powered artificial legs, an interface between user and prosthesis that can recognize the user's movement intent is desired. A novel neural-machine interface (NMI) based on neuromuscular-mechanical fusion developed in our previous study has demonstrated a great potential to accurately identify the intended movement of transfemoral amputees. However, this interface has not yet been integrated with a powered prosthetic leg for true neural control. This study aimed to report (1) a flexible platform to implement and optimize neural control of powered lower limb prosthesis and (2) an experimental setup and protocol to evaluate neural prosthesis control on patients with lower limb amputations. First a platform based on a PC and a visual programming environment were developed to implement the prosthesis control algorithms, including NMI training algorithm, NMI online testing algorithm, and intrinsic control algorithm. To demonstrate the function of this platform, in this study the NMI based on neuromuscular-mechanical fusion was hierarchically integrated with intrinsic control of a prototypical transfemoral prosthesis. One patient with a unilateral transfemoral amputation was recruited to evaluate our implemented neural controller when performing activities, such as standing, level-ground walking, ramp ascent, and ramp descent continuously in the laboratory. A novel experimental setup and protocol were developed in order to test the new prosthesis control safely and efficiently. The presented proof-of-concept platform and experimental setup and protocol could aid the future development and application of neurally-controlled powered artificial legs.

Neural-machine interfaces (NMI) have been developed to identify the user's locomotion mode. These NMIs are potentially useful for neural control of powered artificial legs, but have not been fully demonstrated. This paper presented (1) our designed engineering platform for easy implementation and development of neural control for powered lower limb prostheses and (2) an experimental setup and protocol in a laboratory environment to evaluate neurally-controlled artificial legs on patients with lower limb amputations safely and efficiently.

Mühendisliği Platformu ve Nöral kontrollü Enerjili Transfemoral Protez Tasarım ve Değerlendirme Deneysel Protokol

To enable intuitive operation of powered artificial legs, an interface between user and prosthesis that can recognize the user's movement intent is ...

Harmonic Nanoparticles for Regenerative Research

In this visualized experiment, protocol details are provided for in vitro labeling of human embryonic stem cells (hESC) with second harmonic generation nanoparticles (HNPs). The latter are a new family of probes recently introduced for labeling biological samples for multi-photon imaging. HNPs are capable of doubling the frequency of excitation light by the nonlinear optical process of second harmonic generation with no restriction on the excitation wavelength.
Multi-photon based methodologies for hESC differentiation into cardiac clusters (maintained as long term air-liquid cultures) are presented in detail. In particular, evidence on how to maximize the intense second harmonic (SH) emission of isolated HNPs during 3D monitoring of beating cardiac tissue in 3D is shown. The analysis of the resulting images to retrieve 3D displacement patterns is also detailed.

Protocol details are provided for in vitro labeling human embryonic stem cells with second harmonic generating nanoparticles. Methodologies for hESC investigation by multi-photon microscopy and their differentiation into cardiac clusters are also presented.

Rejeneratif Araştırma harmonik nanopartiküller

In this visualized experiment, protocol details are provided for in vitro labeling of human embryonic stem cells (hESC) with second harmonic generation ...

In Situ Mapping of the Mechanical Properties of Biofilms by Particle-tracking Microrheology

Bacterial cells are able to form surface-attached biofilm communities known as biofilms by encasing themselves in extracellular polymeric substances (EPS). The EPS serves as a physical and protective scaffold that houses the bacterial cells and consists of a variety of materials that includes proteins, exopolysaccharides and DNA. The composition of the EPS may change, which remodels the mechanic properties of the biofilm to further develop or support alternative biofilm structures, such as streamers, as a response to environmental cues. Despite this, there are little quantitative descriptions on how EPS components contribute to the mechanical properties and function of biofilms. Rheology, the study of the flow of matter, is of particular relevance to biofilms as many biofilms grow in flow conditions and are constantly exposed to shear stress. It also provides measurement and insight on the spreading of the biofilm on a surface. Here, particle-tracking microrheology is used to examine the viscoelasticity and effective crosslinking roles of different matrix components in various parts of the biofilm during development. This approach allows researchers to measure mechanic properties of biofilms at the micro-scale, which might provide useful information for controlling and engineering biofilms.

In Situ Mapping of the Mechanical Properties of Biofilms by Particle-tracking Microrheology

Particle-tracking microrheology investigates the viscoelasticity of materials. Here, the technique is used to determine the viscoelasticity, creep compliance and effective crosslinking roles of different matrix components of a bacterial biofilm. The matrix consists of polymeric substances secreted by the bacteria and its components determine biofilm structure and mechanical properties.

Parçacık izleme Microrheology tarafından Biyofilmler Mekanik Özelliklerinin Yerinde Haritalama

Bacterial cells are able to form surface-attached biofilm communities known as biofilms by encasing themselves in extracellular polymeric substances ...

Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that implantation of a bone autograft would induce greater bone regeneration by abundant blood vessel formation. To investigate the effect of the graft on neovascularization at the defect site, we developed a micro&#8211;computed tomography (&#181;CT) approach to characterize newly forming blood vessels, which involves systemic perfusion of the animal with a polymerizing contrast agent. This method enables detailed vascular analysis of an organ in its entirety. Additionally, blood perfusion was assessed using fluorescence imaging (FLI) of a blood-borne fluorescent agent. Bone formation was quantified by FLI using a hydroxyapatite-targeted probe and &#181;CT analysis. Stem cell recruitment was monitored by bioluminescence imaging (BLI) of transgenic mice that express luciferase under the control of the osteocalcin promoter. Here we describe and demonstrate preparation of the allograft, calvarial defect surgery, &#181;CT scanning protocols for the neovascularization study and bone formation analysis (including the in vivo perfusion of contrast agent), and the protocol for data analysis.
The 3D high-resolution analysis of vasculature demonstrated significantly greater angiogenesis in animals with implanted autografts, especially with respect to arteriole formation. Accordingly, blood perfusion was significantly higher in the autograft group by the 7th day after surgery. We observed superior bone mineralization and measured greater bone formation in animals that received autografts. Autograft implantation induced resident stem cell recruitment to the graft-host bone suture, where the cells differentiated into bone-forming cells between the 7th and 10th postoperative day. This finding means that enhanced bone formation may be attributed to the augmented vascular feeding that characterizes autograft implantation. The methods depicted may serve as an optimal tool to study bone regeneration in terms of tightly bounded bone formation and neovascularization.

Implantation of autologous and allogeneic bone grafts constitute accepted approaches to treat major craniofacial bone loss. Yet the effect of graft composition on the interplay among neovascularization, cell differentiation and bone formation is unclear. We present a multimodal imaging protocol aimed to elucidate the angiogenesis-osteogenesis interdependence at the graft proximity.

Bilgisayarlı Tomografi ve Osteogenezi-anjiyogenez bağlamalar Optik Görüntüleme Kranial Kemik Otogreftlerin ve allogreft Entegrasyon değerlendirmek için

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that ...

Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol

Lignocellulosic biomass is an abundant, renewable feedstock useful for production of fuel-grade ethanol and other bio-products. Pretreatment and enzyme saccharification processes release sugars that can be fermented by yeast. Traditional industrial yeasts do not ferment xylose (comprising up to 40% of plant sugars) and are not able to function in concentrated hydrolyzates. Concentrated hydrolyzates are needed to support economical ethanol recovery, but they are laden with toxic byproducts generated during pretreatment. While detoxification methods can render hydrolyzates fermentable, they are costly and generate waste disposal liabilities. Here, adaptive evolution and isolation techniques are described and demonstrated to yield derivatives of the native Scheffersomyces stipitis strain NRRL Y-7124 that are able to efficiently convert hydrolyzates to economically recoverable ethanol despite adverse culture conditions. Improved individuals are enriched in an evolving population using multiple selection pressures reliant on natural genetic diversity of the S. stipitis population and mutations induced by exposures to two diverse hydrolyzates, ethanol or UV radiation. Final evolution cultures are dilution plated to harvest predominant isolates, while intermediate populations, frozen in glycerol at various stages of evolution, are enriched on selective media using appropriate stress gradients to recover most promising isolates through dilution plating. Isolates are screened on various hydrolyzate types and ranked using a novel procedure involving dimensionless relative performance index (RPI) transformations of the xylose uptake rate and ethanol yield data. Using the RPI statistical parameter, an overall relative performance average is calculated to rank isolates based on multiple factors, including culture conditions (varying in nutrients and inhibitors) and kinetic characteristics. Through application of these techniques, derivatives of the parent strain had the following improved features in enzyme saccharified hydrolyzates at pH 5-6: reduced initial lag phase preceding growth, reduced diauxic lag during glucose-xylose transition, significantly enhanced fermentation rates, improved ethanol tolerance and accumulation to 40 g/L.

Adaptive evolution and isolation techniques are described and demonstrated to yield derivatives of Scheffersomyces stipitis strain NRRL Y-7124 that are able to rapidly consume hexose and pentose mixed sugars in enzyme saccharified undetoxified hydrolyzates and to accumulate over 40 g/L ethanol.

Etanol ile lignoselüloz biyo dönüşümünü için Sağlam Pentoz-fermente Maya Evrimi Teknikleri

Lignocellulosic biomass is an abundant, renewable feedstock useful for production of fuel-grade ethanol and other bio-products. Pretreatment and enzyme ...

Production of Metal Nanoparticles by Pulsed Laser-ablation in Liquids: A Tool for Studying the Antibacterial Properties of Nanoparticles

The emergence of multidrug-resistant bacteria is a global clinical concern leading some to speculate about our return to a "pre-antibiotics" era of medicine. In addition to efforts to identify novel small-molecule antimicrobial drugs, there has been great interest in the use of metal nanoparticles as coatings for medical devices, wound dressings, and consumer packaging, due to their antimicrobial properties. The wide variety of methods available for nanoparticle synthesis results in a broad spectrum of chemical and physical properties which can affect antibacterial efficacy. This manuscript describes the pulsed laser-ablation in liquids (PLAL) method to create nanoparticles. This approach allows for the fine tuning of nanoparticle size, composition, and stability using post-irradiation methods as well as the addition of surfactants or volume excluders. By controlling particle size and composition, a large range of physical and chemical properties of metal nanoparticles can be explored which may contribute to their antimicrobial efficacy thereby opening new avenues for antibacterial development.

The antimicrobial properties of metals such as copper and silver have been recognized for centuries. This protocol describes pulsed laser-ablation in liquids, a method of synthesizing metal nanoparticles that provides the ability to fine tune the properties of these nanoparticles to optimize their antimicrobial effects.

Sıvılardaki Darbeli Lazer-Ablasyonuyla Metal Nanopartikül Üretimi: Nanopartiküllerin Antibakteriyel Özelliklerini İncelemek İçin Bir Alet

The emergence of multidrug-resistant bacteria is a global clinical concern leading some to speculate about our return to a "pre-antibiotics" era of ...

Synthesis of Hydrogels with Antifouling Properties As Membranes for Water Purification

Hydrogels have been widely utilized to enhance the surface hydrophilicity of membranes for water purification, increasing the antifouling properties and thus achieving stable water permeability through membranes over time. Here, we report a facile method to prepare hydrogels based on zwitterions for membrane applications. Freestanding films can be prepared from sulfobetaine methacrylate (SBMA) with a crosslinker of poly(ethylene glycol) diacrylate (PEGDA) via photopolymerization. The hydrogels can also be prepared by impregnation into hydrophobic porous supports to enhance the mechanical strength. These films can be characterized by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to determine the degree of conversion of the (meth)acrylate groups, using goniometers for hydrophilicity and differential scanning calorimetry (DSC) for polymer chain dynamics. We also report protocols to determine the water permeability in dead-end filtration systems and the effect of foulants (bovine serum albumin, BSA) on membrane performance.

This paper reports practical methods to prepare hydrogels in freestanding films and impregnated membranes and to characterize their physical properties, including water transport properties.

Su Arıtma Membranlar olarak Zehirli Özelliklere Sahip Hidrojeller Sentezi

Hydrogels have been widely utilized to enhance the surface hydrophilicity of membranes for water purification, increasing the antifouling properties and ...

Semiautomated Longitudinal Microcomputed Tomography-based Quantitative Structural Analysis of a Nude Rat Osteoporosis-related Vertebral Fracture Model

Osteoporosis-related vertebral compression fractures (OVCFs) are a common and clinically unmet need with increasing prevalence as the world population ages. Animal OVCF models are essential to the preclinical development of translational tissue engineering strategies. While a number of models currently exist, this protocol describes an optimized method for inducing multiple highly reproducible vertebral defects in a single nude rat. A novel longitudinal semiautomated microcomputed tomography (&#181;CT)-based quantitative structural analysis of the vertebral defects is also detailed. Briefly, rats were imaged at multiple time points post-op. The day 1 scan was reoriented to a standard position, and a standard volume of interest was defined. Subsequent &#181;CT scans of each rat were automatically registered to the day 1 scan so the same volume of interest was then analyzed to assess for new bone formation. This versatile approach can be adapted to a variety of other models where longitudinal imaging-based analysis could benefit from precise 3D semiautomated alignment. Taken together, this protocol describes a readily quantifiable and easily reproducible system for osteoporosis and bone research. The suggested protocol takes 4 months to induce osteoporosis in nude ovariectomized rats and between 2.7 and 4 h to generate, image, and analyze two vertebral defects, depending on tissue size and equipment.

The goal of this protocol is to generate a nude rat osteoporosis-related vertebral compression fracture model that can be longitudinally evaluated in vivo using a semiautomated microcomputed tomography-based quantitative structural analysis.

Semiautomated boyuna Microcomputed tomografi tabanlı nicel yapısal analizi bir çıplak sıçan vertebra kırığı Osteoporoz ile ilgili Model

Osteoporosis-related vertebral compression fractures (OVCFs) are a common and clinically unmet need with increasing prevalence as the world population ...

A Millimeter Scale Flexural Testing System for Measuring the Mechanical Properties of Marine Sponge Spicules

Many load bearing biological structures (LBBSs)&#8212;such as feather rachises and spicules&#8212;are small (&#60;1 mm) but not microscopic. Measuring the flexural behavior of these LBBSs is important for understanding the origins of their remarkable mechanical functions.
We describe a protocol for performing three-point bending tests using a custom-built mechanical testing device that can measure forces ranging from 10-5 to 101 N and displacements ranging from 10-7 to 10-2 m. The primary advantage of this mechanical testing device is that the force and displacement capacities can be easily adjusted for different LBBSs. The device&#39;s operating principle is similar to that of an atomic force microscope. Namely, force is applied to the LBBS by a load point that is attached to the end of a cantilever. The load point displacement is measured by a fiber optic displacement sensor and converted into a force using the measured cantilever stiffness. The device&#39;s force range can be adjusted by using cantilevers of different stiffnesses.
The device&#39;s capabilities are demonstrated by performing three-point bending tests on the skeletal elements of the marine sponge Euplectella aspergillum. The skeletal elements&#8212;known as spicules&#8212;are silica fibers that are approximately 50 &#181;m in diameter. We describe the procedures for calibrating the mechanical testing device, mounting the spicules on a three-point bending fixture with a &#8776;1.3 mm span, and performing a bending test. The force applied to the spicule and its deflection at the location of the applied force are measured.

We present a protocol for performing three-point bending tests on sub-millimeter scale fibers using a custom-built mechanical testing device. The device can measure forces ranging from 20 &#181;N up to 10 N and can therefore accommodate a variety of fiber sizes.

Deniz sünger Spicules mekanik özelliklerini ölçmek için bir milimetre ölçek bükülme test sistemi

Many load bearing biological structures (LBBSs)&#8212;such as feather rachises and spicules&#8212;are small (&#60;1 mm) but not microscopic. Measuring the ...