역학의 미국 및 국제 사회에서의 자금 조달은이 연구를 위해 제공되었다.

<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>

저자는 더 경쟁 재정적 이익이 없다는 것을 선언합니다.

경험적인 데이터로 작업 할 때 이동 중에 그 결과 관절의 힘과 모멘트를 정량화하기 위해, 관심의 시스템의 역 동성 모델이 필요합니다. 낮은 말단 역학의 경우, 역 동성 모델은 일반적으로 정강이를 발을 대표하고 강체 허벅지. ) 운동 역학, B) 지상 반력 및 C) 세그먼트 anthropometrics 관성 속성 :이 모델에 대한 입력은 세 가지 기본 소스에서 온. 모션 데이터는 모션 분석​​ 시스템의 다양한 수집하지만 모든 시스템은 본질적으로 이동 (위치, 속도 및 가속도)의 기본적인 운동학을 제공한다. 지면 반력은 포스 플레이트 수집 피트에 작용하는 접촉력을 제공한다. Anthropometrics 눈금자, 유연한 테이프 및 / 또는 캘리퍼스를 이용하여 본체에서 직접 찍은 측정을 예로들 수 있습니다. 이러한 인체 측정은 역 dynami 사용될 바디 부분의 관성 특성을 추정하기 위해 이용된다CS는 분석한다. 관성 속성은 세그먼트 COM 또는 근위부 또는 원위부 관절을 통해 축 세그먼트의 상대적 질량의 질량 중심 (COM)의 위치와 관성 모멘트 (MOI)를 포함한다. 모션 및 지상 반력 데이터를 수집하기 위해 사용되는 방법 및 장치는 연구 그룹들과 유사하지만, 보디 세그먼트의 관성 추정은 연구자가 이들 관성 특성을 추정하기 위해 선택되는 방법에 따라 연구자마다 크게 달라질 수있다. 완전히 그대로 인간의 몸 세그먼트의 관성 특성을 추정 사용할 수있는 다양한 기술은 다음을 포함한다 : 1) 시신 데이터 1-5, 2) 수학적 모델 (즉, 기하학적 모델) 6,7, 3) 스캔 및 이미징 기술을 기반으로 회귀 방정식 8-15. 이들 기술의 대부분은 본체에서 직접 측정을 필요로하지만, 그것은 이전에 관계없이 추정 방법이 사용되는 것으로 본체 SEG의 정밀도를 보여왔다이 방법에 따라, 표준 관성 추정 높은 16입니다. 또한, 그대로 몸 세그먼트의 관성 특성의 추정에 오류가 (17, 18)를 보행시 결과 공동 순간의 크기에 미치는 영향을 최소화 것으로 나타났습니다. 조인트 모멘트 지상 반력 압력 명소 모멘트 아암 길이 및 세그먼트 운동학 17-19의 중심에서 더 큰 정도로 영향을 받는다. 따라서, 연구 참가자가 이러한 추정의 작은 오류가 연구의 결과에 거의 영향을 미칠 가능성이있는 것으로 주어진 할 수있는 개인을 사용할 때 몸 세그먼트의 관성 특성을 추정하는 방법은 문헌에 걸쳐 다양 것은 놀라운 일이 아니다. 완전히 그대로 몸 세그먼트에 대한 이러한 관성 추정의 대부분은 종종 낮은 말단 절단 수술을받은 사람을위한 보철물의 관성 특성을 추정하는 데 사용됩니다. 현대 하체 보철은 경량 소재를 사용하여 제조된다 resultiNG가 대체 사지보다 훨씬 가볍고 인공 사지. 이 인공 사지 그대로 다리 사이의 관성 비대칭에서 발생합니다. 전형적인 그대로 정강이와 발, 무릎 아래 보철물의 질량과 절단 단에 비해 약 35 % 이하이며, 슬관절 20-23 약 35 % 가까이 위치 대량의 센터가 있습니다. 낮은 질량 및 사지 ​​보철보다 근위 질량 분포는 그대로 생크 및 다리에 비해 사지 보철을위한 무릎 관절에 관성 상대적인 훨씬 낮은 (~ 60 %) 모멘트를 생성한다. 연구자 24,25 이전 보철 다리 속담 관성 추정들을 사용하여 관절 운동 추정치에 거의 영향을 가질 것을 제안했지만, 이러한 비교는지면 반력에서 발생 순간을 지배 걷는 자세 단계 동안 얻어진 조인트 순간에 집중 공동. 스윙 도중, 여기서 접지 반력은 존재하지보철물의 감소 관성 속성은 결과 공동 순간의 추정에 영향을 미칠 가능성이 더 높습니다. 일부 연구자들은 예를 들어 점을 감안, 26 ~ 32은 보철물 관성 특성을 표현하기 위해 그대로 세그먼트 관성 특성을 활용하고 다른 사람은 보철물의 관성 특성을 추정하기 위해 선택된 방법의 영향을 이해하는 것이 중요합니다, 직접 21-23 추정 보철물 관성 속성을 예 . 보철물의 관성 특성을 측정하기 위해 필요한 시간을 최소화하는 것이 우리의 기술의 개발에 중요한 고려 사항이었다. 모든 측정은 측정 한 후 보철물을 재조정과 관련된 추가 시간을 측정 시간을 줄이고 방지하기 위해 여기에 제시된 기술에 보철물을 완전히 그대로 유지됩니다. 따라서, 본 연구의 목적은 두 가지 있었다 : 1) AB의 관성 특성을 추정하기 위해 직접 사용할 수있는 기술을 보여elow 무릎 보철물, 2) 일방적, transtibial 절단 수술을받은 사람의 보행시 관절 운동 추정에 그대로 사지 관성 속성을 사용하여 제안 된 기술과 그 효과를 대조. 그것은 그대로 정강이와 발 관성 속성이 보철물 관성 특성을 직접 측정 비교 보철물의 관성 추정으로 사용되는 경우 관절 운동, 등급이 큰 것으로 가정했다.

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			<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

본 연구의 목적은 두 가지 있었다 : 1) 바로 아래의 무릎 보철의 관성 특성을 추정하기 위해 사용될 수있는 기술을 설명하고, 2) 그대로 가지 관성 특성을 사용하는 제안 된 기술과 그 효과를 대비 일방적 transtibial 절단 수술을받은 사람의 보행시 관절 운동 추정에. 진동 반응 보드 시스템의 유효성을 검사하고 알려진 기하학적 고체의 관성 특성을 측정 할 때 신뢰할 수있는 것으로 나타났다. 보철물의 관성 특성을 직접 측정이 그대로 정강이와 발을 기준으로 관성 추정에 비해 낮은 말단의 역 동성 모델링에 사용되었을 때, 허리와 무릎의 관절 반응 속도는 걷는 스윙 단계에서 유의하게 낮았다. 입장시 공동 역학의 차이는, 그러나, 스윙 동안 관찰보다 작았 다. 따라서, 걷기의 스윙 단계에 초점을 맞추고 연구원은 prosthes의 영향을 고려해야한다연구 결과에 관성 속성 추정이다. 입장을 위해, 우리의 연구에서 조사 두 관성 모델 중 하나는 가능성이 역 동성 평가와 유사한 결과로 이어질 것입니다.

무릎에 인공 다리 말단의 관성 특성은 그대로 다리 (표 1)에 비해 낮았다. 참가자 걸쳐 평균화, 보철 측 질량 무릎 통해 횡단 축 주위의 관성 모멘트가 52 % 이하이고, 39 % 이하이고, 질량의 위치의 중심이 그대로 발에 대한 값과 비교 무릎 24 % 가까이되었다. <table border="1" cellpadding="0" cellspacing="0" fo:keep-together.within-page="always" width="553"><tbody><tr><td> 제목 </td><td> 그대로 * 질량 (kg) </td><td> 질량 † 프로 (kg) </td><td> EST. 질량 차이 (kg) </td><td> ‡ Iknee 그대로 (kg · m 2) </td><td> Iknee 프로 (kg · m 2) </td><td> 무릎 관절 아래에 그대로 CM (M) </td><td> 무릎 관절 아래 프로의 CM (M) </td></tr><tr><td> </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> 디 </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> E </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> 에프 </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> ± STD에게 의미 </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> * 비 손상이 결합 된 그대로 정강이와 발에 대한 값을 의미한다. † 장점이 결합 된 보철물과 절단 단의 값을 의미한다. 무릎을 통해 가로 축에 대한 관성 모멘트 ‡. 아래 무릎의 인공 그대로 사지 사이의 관성 특성 표 1. 비교. 결과 연합군 (그림 3)과 순간 발목에서 (그림 4), 무릎, 엉덩이는 역 동성 모델에 사용되는 관성 매개 변수에 의해 영향을 받았다. 보철물 관성의 직접적인 조치가 그대로 해부학 (에 따라 회귀에 비해 역 동성 평가에 사용 된 경우 특히, 공동 역학은 스윙의 시작 (~ 보행주기의 65 %)와 스윙 종료 (~ 보행주기의 95 %) 동안 감소했다 <strong&gt; 표 2). 효과의 크기는 스윙하는 동안 이러한 차이는 (≥ 1.0) 사소한되지 않은 것이 좋습니다. 그대로 관성 추정을 사용할 때뿐만 아니라, 관절 운동 값은 보철물 관성 특성을 직접 측정과 비교 스윙의 시작과 종료시 80 %까지 평균 증가했다. 그대로 다리의 관성 속성이 보철 측면을 모델링하는 데 사용 때 따라서, 스윙하는 동안 인공 측의 공동 운동 프로파일은 더 밀접하게 (그림 3, 4 참조) 그대로 사지의 것과 닮았다. 자세 동안 통계적 차이 수가 관찰되었다. 입장시 어떤 차이가 가장 큰 효과 크기는 엉덩이 anterioposterior 결과 공동의 힘 (= 0.86 ES) 관찰되었다. 이 효과의 크기가 크고 아직 입장의 한 부분으로 간주되지만,이 측정 값의 최대 값은 단말기의 자세 (~ 52 %)하는 동안 오류가 발생했습니다, 또는 사지 스윙으로 전환되었을 때. 다른 뜻인지에 대한 효과 크기자세 동안 관찰 NT의 차이는 엉덩이 결과 공동 반력에서 관찰되는 이러한 값 중 큰 작은 효과로 간주 될 수있는, 0.01-0.41였다. 큰 차이는 자세에서 발견되었지만, 그 차이 (즉, 효과의 크기)의 크기의 측면에서 고려 이러한 차이는이 차이의 유의성에 의문을 초래할 수 있습니다. <img alt="그림 3" fo:content-width="5in" src="/files/ftp_upload/50977/50977fig3highres.jpg" width="500" /> 그림 3. anterioposterior (왼쪽 패널) 및 수직 방향 (오른쪽 패널)에서 발목, 무릎, 엉덩이의 결과적인 공동 반력. 데이터는 프레 젠 테이션을위한 과목에 걸쳐 평균 하였다. 자세 단계는 발 접촉 보행주기의 0 %에서 시작하여 발가락 오프와 보행주기의 약 60 %에서 끝납니다. 스윙은 t의 다음 발에 닿을 때까지 계속그는 보행주기의 100 % 같은 다리. <a href="https://www.jove.com/files/ftp_upload/50977/50977fig3highres.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a> <img alt="그림 4" fo:content-width="5in" src="/files/ftp_upload/50977/50977fig4highres.jpg" width="500" /> 그림 4. 발목, 무릎, 엉덩이를 통해 가로 축 (일명, 내 외측 축)에 대한 결과적인 공동 순간. 데이터는 프레 젠 테이션을위한 과목에 걸쳐 평균 하였다. 자세 단계는 발 접촉 보행주기의 0 %에서 시작하여 발가락 오프와 보행주기의 약 60 %에서 끝납니다. 스윙은 보행주기의 100 %에서 같은 다리의 다음 발에 닿을 때까지 계속됩니다. <img alt="표 2" fo:content-width="6in" src="/files/ftp_upload/50977/50977table2.jpg" width="600" /> 표 2. 피크 결과 공동 반응힘과 모멘트는 보철 팀의 공동 역학에 대한 주제와 두 관성 모델 사이의 통계적 비교를 통해 평균주의 사항 :. 평균 데이터는 평균 (SD)로 표시됩니다. % 보행주기의 열은 피크 값이 그 변수의 발생 과목에 걸쳐 평균 비율을 나타냅니다. p &lt;.05 중요하게 고려.

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

신체 분절의 관성 특성은 역 동성 모델링이 필요합니다. 진동 반응 보드 기술, 아래 - 무릎 보철의 관성 특성을 사용하는 것은 측정 하였다. 보철 다리의 역 동성 모델에 보철물 관성의 직접적인 조치를 사용하면 결과 공동 힘과 모멘트의 낮은, 등급 결과.

아래 - 무릎 보철물의 추정 관성 속성에 대한 진동 및 반응 보드 기술

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 ...

oscillation-reaction-board-techniques-for-estimating-inertial

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16.6K 조회수.  University of Northern Colorado.  신체 분절의 관성 특성은 역 동성 모델링이 필요합니다. 진동 반응 보드 기술, 아래 - 무릎 보철의 관성 특성을 사용하는 것은 측정 하였다. 보철 다리의 역 동성 모델에 보철물 관성의 직접적인 조치를 사용하면 결과 공동 힘과 모멘트의 낮은, 등급 결과. 

비디오: 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).

원자 힘 현미경을 사용하여 살아있는 세포의 기계적 특성을 측정

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

연구

생체공학

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.

엔지니어링 플랫폼 및 Neurally 통제 강화 대퇴 보철물의 설계 및 평가를위한 실험 프로토콜

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.

재생 연구를위한 고조파 나노 입자

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.

입자 추적 Microrheology에 의한 바이오 필름의 기계적 성질의 제자리 매핑에서

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.

컴퓨터 단층 촬영 및 골 형성 - 혈관 신생 커플 링의 광학 이미징 두개골 뼈자가 이식과 동종 이식 통합을 평가하기 위해

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.

에탄올에 리그 노 셀룰로즈의 생물에 대한 강력한 펜 토스 발효 효모의 진화를위한 기술

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.

액체에서의 펄스 레이저 어블 레이션에 의한 금속 나노 입자의 제조 : 나노 입자의 항균성 연구를위한 도구

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.

물 정화를위한 막으로 방오 특성을 가진 히드로 겔의 합성

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.

반자동 경도 Microcomputed Tomography 기반 정량적 구조 분석 누드 쥐 척추 골절 골다공증 관련 모델의

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.

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