scholarly journals Segmental volume and circulatory changes that occur in humans and Rhesus monkeys during 4 hour, −6 degree head down tilt

2021 ◽  
Vol 12 (1) ◽  
pp. 11-16
Author(s):  
Leslie David Montgomery ◽  
Clarence Oloff

Abstract Nonhuman primates are often used to investigate physiologic processes that occur in man during aerospace/cardiovascular orthostatic research. Few studies have compared nonhuman primates and man under identical test conditions to assess the degree of similarity between the two species. Impedance plethysmography was used to measure calf, thigh, pelvic, thoracic, upper arm, and lower arm volume changes in eight rhesus (Macacca Mulatta) monkeys and twelve human subjects during four hour exposures to −6 degree head down tilt (HDT).

2020 ◽  
Vol 11 (1) ◽  
pp. 12-18
Author(s):  
Leslie David Montgomery ◽  
Clarence Oloff

AbstractNonhuman primates are often used in biomedical research and to investigate physiologic processes that occur in man. Impedance plethysmography was used to measure calf, thigh, pelvic, abdominal, and thoracic volume changes in ten Rhesus and eight squirrel monkeys during five-minute exposures to HUT and HDT at angles of 5, 10, and 20 degrees. Calf, rump and tail measurements were made in three squirrel monkeys at 10 and 20 degrees of HUT and HDT. Fluid volume changes in all segments of the Rhesus monkeys were found to change during HUT an HDT in direct relation to the angle of tilt used. However, the volume changes that occurred in the squirrel monkeys were found to be quite different. Their calf, thigh, and pelvic segments lost volume during both HUT and HDT while their abdominal and thoracic segments responded similarly to those of the Rhesus monkeys. These results and those of the calf/tail measurements of the squirrel monkeys suggest that they may utilize their tails as a compensatory reservoir during postural changes and therefore, may not be an appropriate animal model for man under some orthostatic test conditions.


1998 ◽  
Vol 26 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Gerald Schatten ◽  
Laura Hewitson ◽  
Calvin Simerly ◽  
Peter Sutovsky ◽  
Gabor Huszar

The general perception of how innovative assisted reproductive technologies (ART) are introduced is through a carefully controlled series of experiments in an animal model, such as the mouse. Only after the technique has been proven can one consider confirmatory studies on mammals closely related to humans, such as rhesus monkeys or other nonhuman primates. With this background of a peer-reviewed body of well-established published data, there is sufficient foundation and rationale to propose a clinical investigation to a responsible human subjects institutional review board (IRB). IRBs weigh the benefits and risks of the new methods to human subjects, and then consider the appropriate informed consent procedures for the particular case. Only after a large number of clinical studies are performed at multiple sites and are peer reviewed can the efficacy and safety of the innovative approach be clearly evaluated. At that time, the potential therapy can be responsibly offered to suitable beneficiaries.


Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2157
Author(s):  
Kevin Langlois ◽  
Ellen Roels ◽  
Gabriël Van De Velde ◽  
Cláudia Espadinha ◽  
Christopher Van Vlerken ◽  
...  

Sensing pressure at the physical interface between the robot and the human has important implications for wearable robots. On the one hand, monitoring pressure distribution can give valuable benefits on the aspects of comfortability and safety of such devices. Additionally, on the other hand, they can be used as a rich sensory input to high level interaction controllers. However, a problem is that the commercial availability of this technology is mostly limited to either low-cost solutions with poor performance or expensive options, limiting the possibilities for iterative designs. As an alternative, in this manuscript we present a three-dimensional (3D) printed flexible capacitive pressure sensor that allows seamless integration for wearable robotic applications. The sensors are manufactured using additive manufacturing techniques, which provides benefits in terms of versatility of design and implementation. In this study, a characterization of the 3D printed sensors in a test-bench is presented after which the sensors are integrated in an upper arm interface. A human-in-the-loop calibration of the sensors is then shown, allowing to estimate the external force and pressure distribution that is acting on the upper arm of seven human subjects while performing a dynamic task. The validation of the method is achieved by means of a collaborative robot for precise force interaction measurements. The results indicate that the proposed sensors are a potential solution for further implementation in human–robot interfaces.


Author(s):  
T J Jemi Jeya ◽  
V Sriram ◽  
V Sundar

This paper presents the results from a comprehensive experimental study on the Quadrant Face Pile Supported Breakwater (QPSB) in two different water depths exposed to three different oblique wave attacks. The results are compared with that for a Vertical face Pile Supported Breakwater (VPSB) for identical test conditions. The paper compares the reflection coefficient, transmission coefficient, energy loss coefficient, non-dimensional pressure, and non-dimensional run-up as a function of the relative water depth and scattering parameter. The results obtained for QPSB are validated with existing results. The salient observations show that QPSB experiences better hydrodynamic performance characteristics than the VPSB under oblique waves.


2013 ◽  
Vol 3 (5) ◽  
pp. 575-595 ◽  
Author(s):  
Pauline Chatagny ◽  
Simon Badoud ◽  
Mélanie Kaeser ◽  
Anne-Dominique Gindrat ◽  
Julie Savidan ◽  
...  

1977 ◽  
Vol 99 (2) ◽  
pp. 126-132 ◽  
Author(s):  
L. K. Ives

Erosion tests were conducted on 310 stainless steel in combustion gas atmospheres at 975°C. SiC particles of 100 mesh (150 μm) size were employed over a velocity range of 15–70 m/s at a 90 deg (perpendicular) angle of impingement. A comparison is made with results obtained at 25°C in air using the same test equipment. Scanning electron microscopy examination of the eroded surfaces revealed important information concerning the nature of the erosion-corrosion process. A multiple component test specimen is described for application in comparing alloys under nearly identical test conditions.


2001 ◽  
Vol 13 (3) ◽  
pp. 319-331 ◽  
Author(s):  
Daeyeol Lee ◽  
Nicholas L. Port ◽  
Wolfgang Kruse ◽  
Apostolos P. Georgopoulos

Two rhesus monkeys were trained to intercept a moving target at a fixed location with a feedback cursor controlled bya 2-D manipulandum. The direction from which the target appeared, the time from the target onset to its arrival at the interception point, and the target acceleration were randomized for each trial, thus requiring the animal to adjust its movement according to the visual input on a trail-by-trail basis. The two animals adopted different strategies, similar to those identified previously in human subjects. Single-cell activity was recorded from the arm area of the primary motor cortex in these two animals, and the neurons were classified based on the temporal patterns in their activity, using a nonhierarchical cluster analysis. Results of this analysis revealed differences in the complexity and diversity of motor cortical activity between the two animals that paralleled those of behavioral strategies. Most clusters displayed activity closedly related to the kinematics of hand movements. In addition, some clusters displayed patterns of activation that conveyed additional information necessary for successful performance of the task, such as the initial target velocity and the interval between successive submovements, suggesting that such information is represented in selective subpopulations of neurons in the primary motor cortex. These results also suggest that conversion of information about target motion into movement-related signals takes place in a broad network of cortical areas including the primary motor cortex.


2019 ◽  
Vol 3 (17) ◽  
pp. 2632-2641 ◽  
Author(s):  
David Salas ◽  
Karin L. Kwikkers ◽  
Nerea Zabaleta ◽  
Andrea Bazo ◽  
Harald Petry ◽  
...  

Abstract Adeno-associated virus (AAV)–based liver gene therapy has been shown to be clinically successful. However, the presence of circulating neutralizing antibodies (NABs) against AAV vector capsids remains a major challenge as it may prevent successful transduction of the target cells. Therefore, there is a need to develop strategies that would enable AAV-mediated gene delivery to patients with preexisting anti-AAV NABs. In the current study, the feasibility of using an immunoadsorption (IA) procedure for repeated, liver-targeted gene delivery in nonhuman primates was explored. The animals were administered IV with recombinant AAV5 (rAAV5) carrying the reporter gene human secreted embryonic alkaline phosphatase (hSEAP). Seven weeks after the first rAAV treatment, all of the animals were readministered with rAAV5 carrying the therapeutic hemophilia B gene human factor IX (hFIX). Half of the animals administered with rAAV5-hSEAP underwent IA prior to the second rAAV5 exposure. The transduction efficacies of rAAV5-hSEAP and rAAV5-hFIX were assessed by measuring the levels of hSEAP and hFIX proteins. Although no hFIX was detected after rAAV5-hFIX readministration without prior IA, all animals submitted to IA showed therapeutic levels of hFIX expression, and a threshold of anti-AAV5 NAB levels compatible with successful readministration was demonstrated. In summary, our data demonstrate that the use of a clinically applicable IA procedure enables successful readministration of an rAAV5-based gene transfer in a clinically relevant animal model. Finally, the analysis of anti-AAV NAB levels in human subjects submitted to IA confirmed the safety and efficacy of the procedure to reduce anti-AAV NABs. Furthermore, clinical translation was assessed using an immunoglobulin G assay as surrogate.


2011 ◽  
Vol 27 (3) ◽  
pp. 258-265 ◽  
Author(s):  
Yanxin Zhang ◽  
David G. Lloyd ◽  
Amity C. Campbell ◽  
Jacqueline A. Alderson

The purpose of this study was to quantify the effect of soft tissue artifact during three-dimensional motion capture and assess the effectiveness of an optimization method to reduce this effect. Four subjects were captured performing upper-arm internal-external rotation with retro-reflective marker sets attached to their upper extremities. A mechanical arm, with the same marker set attached, replicated the tasks human subjects performed. Artificial sinusoidal noise was then added to the recorded mechanical arm data to simulate soft tissue artifact. All data were processed by an optimization model. The result from both human and mechanical arm kinematic data demonstrates that soft tissue artifact can be reduced by an optimization model, although this error cannot be successfully eliminated. The soft tissue artifact from human subjects and the simulated soft tissue artifact from artificial sinusoidal noise were demonstrated to be considerably different. It was therefore concluded that the kinematic noise caused by skin movement artifact during upper-arm internal-external rotation does not follow a sinusoidal pattern and cannot be effectively eliminated by an optimization model.


2018 ◽  
Vol 22 (2) ◽  
pp. 209-222
Author(s):  
Fangfang Zhang ◽  
Trevor John Little

Purpose 3D garment design technology is developing rapidly thereby creating a need for different approaches to developing the patterns. The purpose of this paper is to evaluate the 3D dynamic ease distribution for a 3D garment design. Design/methodology/approach Standard garments were created from Size 2 to Size 14 for ten human subjects. Landmarks location on both human body and the standard garment under dynamic postures are recorded, and he fit and comfort evaluation of the standard garment were collected from the ten human subjects. Finally, these data were used to evaluate the 3D dynamic ease distribution for a 3D garment design. Findings 3D dynamic ease evaluation is challenging and the findings showed that the upper-arm design is a core element of the whole 3D garment design. The upper arm is not only a connecting part for both front and back pieces of the garment, but is also the main active part of the body, so it is the essential element to affect the comfort and fit of the garment under dynamic postures. Originality/value This research provides a novel 3D ease evaluation by analyzing the landmarks location of both human body and standard garment, and fit and comfort evaluation of the standard garment, which are all carried under dynamic postures.


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