{"title":"Haemodynamic responses to varying postural stress","authors":"R. Paz, S. Al-Dhaheri, H. Sun, L. Hrebien","doi":"10.1109/NEBC.1994.305179","DOIUrl":"https://doi.org/10.1109/NEBC.1994.305179","url":null,"abstract":"The authors present data demonstrating early cardiovascular responses to simulated gravity levels between 1G and -1G. A noninvasive, cardiac impedance cardiography system (the IQ System) was used to evaluate cardiac output (CO), stroke volume (SV), ventricular ejection time (VET), ejection fraction (EF), and pre-ejection period (PEP). Seven subjects were positioned at selected angles of +90/spl deg/, +45/spl deg/, 0/spl deg/, -45/spl deg/, and -90/spl deg/ for five minutes at each angle. These postural changes simulate different gravitational forces on the human body ranging from +1G to -1G. This study's findings demonstrate an overall increasing trend in CO, SV, VET and EF, and a slight decrease in PEP with postural changes from +90/spl deg/ to -90/spl deg/. Findings may aid responses to low and negative gravity environments.<<ETX>>","PeriodicalId":117140,"journal":{"name":"Proceedings of 1994 20th Annual Northeast Bioengineering Conference","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115288843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. V. Gundlapalli, C. W. Mayott, Mark C. Zimmerman, John R. Parsons, Joseph Benevenia
{"title":"An analysis of a custom expanding total femoral prosthesis with a rotating hinge knee","authors":"R. V. Gundlapalli, C. W. Mayott, Mark C. Zimmerman, John R. Parsons, Joseph Benevenia","doi":"10.1109/NEBC.1994.305184","DOIUrl":"https://doi.org/10.1109/NEBC.1994.305184","url":null,"abstract":"Osteosarcoma is the most common malignant bone tumor in the pediatric age group. The authors present an analysis of a custom total femoral prosthesis implanted in March 1992 in a 9 year old black male suffering from osteosarcoma. The custom design included a bipolar, expanding tube-in-tube mid-shaft component, and a rotating hinge knee used in the reconstruction of the patient's right lower limb after surgical resection of the femur. The areas analyzed were (i) the trochanteric attachment, (ii) the expanding component, and (iii) the rotating hinge knee. The greater trochanter was cabled around the prosthesis in order to maintain abduction and to provide proximal stability. The muscle maintained the vascularity of the bone. A porous surface on the prosthesis allowed bone ingrowth and stability. The stresses acting on the stainless steel multifilament cables reconnecting the greater and lesser trochanter were determined for bipedal stance, single-legged stance, stance phase of gait and running of the patient. They were calculated to be 0.5 MPa, 17 MPa, 23 MPa and 51 MPa respectively. On comparing these stresses to the fatigue data for stainless steel cables, it is estimated that the cables will last for 10/sup 8/ cycles which is approximated to be 10 years of usage. The expanding midshaft was designed to provide the required lengthening of the femur as the patient grows. A telescoping tube-in-tube with a cross pin was the design chosen because of minimal micromotion and wear.<<ETX>>","PeriodicalId":117140,"journal":{"name":"Proceedings of 1994 20th Annual Northeast Bioengineering Conference","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125026797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design and construction of an electro-mechanical bowling system","authors":"R. Herrmann, P.D. Irelan, R. K. Oberg","doi":"10.1109/NEBC.1994.305195","DOIUrl":"https://doi.org/10.1109/NEBC.1994.305195","url":null,"abstract":"This project describes the design and construction of an electromechanical device to help handicapped people candlepin bowl more independently. Five sub-systems were designed: an aiming system, a firing system, a reloading system, a user interface, and electronic logic to control all of the systems. The user controls all aspects of the aiming and firing of the howling ball. Through the use of a control panel the user can move a joystick to change the aim, slide a lever to change the speed, or push a button to fire a ball. The aiming system allows the user to control where the bail is fired both laterally and rotationally. The firing system is powered by a compressed spring. Once the ball has been fired the reloading system automatically loads another ball. Each mechanical sub-system was constructed and tested to assure the system work as designed. The system will be used at the Massachusetts Hospital School as an educational and recreational device.<<ETX>>","PeriodicalId":117140,"journal":{"name":"Proceedings of 1994 20th Annual Northeast Bioengineering Conference","volume":"72 1-2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116720901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}