WorldWideScience

Sample records for artificial limbs

  1. Artificial Limbs

    Science.gov (United States)

    ... diabetes. They may cause you to need an amputation. Traumatic injuries, including from traffic accidents and military combat Cancer Birth defects If you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which is ...

  2. Adjustments to amputation and an artificial limb in lower limb amputees

    NARCIS (Netherlands)

    Sinha, Richa; van den Heuvel, Wim J. A.; Arokiasamy, Perianayagam

    2014-01-01

    Background: Positive adjustments to amputation and an artificial limb play important roles in the rehabilitation process. Objectives: To study the different facets of adjustments to amputation and an artificial limb in lower limb amputees and to assess the possible role of different background and a

  3. Myoelectric Control of Artificial Limb by Quantum Information Processing

    CERN Document Server

    Siomau, Michael

    2013-01-01

    Precise and elegant coordination of a prosthesis across many degrees of freedom is highly desired for rehabilitation of people with limb deficiency. Processing the electrical neural signals, collected from the surface of the remnant muscles of the stump, is a common way to activate certain function of the artificial limb. Based on the assumption that there are distinguishable and repeatable signal patterns among different types of muscular activation, the problem of the prosthesis control reduces to the pattern recognition. Widely accepted classical methods for pattern recognition, however, can not provide simultaneous and proportional control of the artificial limb. Here we show that quantum information processing of the neural signals allows us to overcome above difficulties suggesting a very simple scheme for myoelectric control of artificial limb with advanced functionalities.

  4. Myoelectric control of artificial limb inspired by quantum information processing

    Science.gov (United States)

    Siomau, Michael; Jiang, Ning

    2015-03-01

    Precise and elegant coordination of a prosthesis across many degrees of freedom represents a significant challenge to efficient rehabilitation of people with limb deficiency. Processing the electrical neural signals collected from the surface of the remnant muscles of the stump is a common way to initiate and control the different movements available to the artificial limb. Based on the assumption that there are distinguishable and repeatable signal patterns among different types of muscular activation, the problem of prosthesis control reduces to one of pattern recognition. Widely accepted classical methods for pattern recognition, however, cannot provide simultaneous and proportional control of the artificial limb. Here we show that, in principle, quantum information processing of the neural signals allows us to overcome the above-mentioned difficulties, suggesting a very simple scheme for myoelectric control of artificial limb with advanced functionalities.

  5. [History of artificial limbs for the leg].

    Science.gov (United States)

    Wetz, H H; Gisbertz, D

    2000-12-01

    Following the development of prosthetics for the lower limb since the middle of the 18th century one will find very interesting similarities to modern prostheses. This becomes evident when looking at former knee and ankle joint mechanisms or socket designs. Also, the materials used for the prostheses underwent very interesting variations. In our paper we will describe the development of socket designs and several materials from the beginning of the 19th century. Several still obtainable books dealing with 200 years of prosthetics development, were reviewed. Charles White describes in the year 1761 a supramalleolar amputation using the flap technique and the specially built BK prostheses the socket. V. Brünninghausen describes in 1809 a socket made of tin sheet. It was built oval, as the normal transverse section of the thigh is. Stump adhesion was obtained when a shortly trimmed dog fur--panelling the socket and covering the stump--was attached like brushes end on end. A similar fitting was described by Heine in 1811, v. Dornblüth in 1831, and Mrs. Eichler in 1836. Hermann first mentioned the need of a perpendicular construction of prostheses. Parmelee developed in 1868 the first suction socket. The first tuber-enclosing socketdesign was made by Riedel in 1911. We will show documents from this time and will also show, that muscle-physiological aspects had a very important influence on socket designs.

  6. The fastest runner on artificial legs: different limbs, similar function?

    Science.gov (United States)

    Weyand, Peter G; Bundle, Matthew W; McGowan, Craig P; Grabowski, Alena; Brown, Mary Beth; Kram, Rodger; Herr, Hugh

    2009-09-01

    The recent competitive successes of a bilateral, transtibial amputee sprint runner who races with modern running prostheses has triggered an international controversy regarding the relative function provided by his artificial limbs. Here, we conducted three tests of functional similarity between this amputee sprinter and competitive male runners with intact limbs: the metabolic cost of running, sprinting endurance, and running mechanics. Metabolic and mechanical data, respectively, were acquired via indirect calorimetry and ground reaction force measurements during constant-speed, level treadmill running. First, we found that the mean gross metabolic cost of transport of our amputee sprint subject (174.9 ml O(2)*kg(-1)*km(-1); speeds: 2.5-4.1 m/s) was only 3.8% lower than mean values for intact-limb elite distance runners and 6.7% lower than for subelite distance runners but 17% lower than for intact-limb 400-m specialists [210.6 (SD 13.2) ml O(2)*kg(-1)*km(-1)]. Second, the speeds that our amputee sprinter maintained for six all-out, constant-speed trials to failure (speeds: 6.6-10.8 m/s; durations: 2-90 s) were within 2.2 (SD 0.6)% of those predicted for intact-limb sprinters. Third, at sprinting speeds of 8.0, 9.0, and 10.0 m/s, our amputee subject had longer foot-ground contact times [+14.7 (SD 4.2)%], shorter aerial [-26.4 (SD 9.9)%] and swing times [-15.2 (SD 6.9)%], and lower stance-averaged vertical forces [-19.3 (SD 3.1)%] than intact-limb sprinters [top speeds = 10.8 vs. 10.8 (SD 0.6) m/s]. We conclude that running on modern, lower-limb sprinting prostheses appears to be physiologically similar but mechanically different from running with intact limbs.

  7. Proprioception in Above-the-Knee Amputees with Artificial Limbs

    OpenAIRE

    Latanioti, E. P.; Angoules, A. G.; Boutsikari, E. C.

    2013-01-01

    Purpose. To evaluate the lower limb proprioceptive sensation in patients with femoral amputation who received an artificial joint. Materials and Methods. 22 patients (18 men, 4 women), 24–65 years old (mean: 42), who had undergone above-the-knee joint amputation and underwent evaluation of proprioception using joint reposition in a predetermined angle of 15° knee flexion. The measurements were applied using a conventional goniometer to both amputated and healthy knees. The last ones were u...

  8. Proprioception in Above-the-Knee Amputees with Artificial Limbs

    Directory of Open Access Journals (Sweden)

    E. P. Latanioti

    2013-01-01

    Full Text Available Purpose. To evaluate the lower limb proprioceptive sensation in patients with femoral amputation who received an artificial joint. Materials and Methods. 22 patients (18 men, 4 women, 24–65 years old (mean: 42, who had undergone above-the-knee joint amputation and underwent evaluation of proprioception using joint reposition in a predetermined angle of 15° knee flexion. The measurements were applied using a conventional goniometer to both amputated and healthy knees. The last ones were used as internal control. All patients performed an active knee flexion from hyperextension to 15° in a closed kinetic chain in order to evaluate proprioceptive sensation of the knee joint using the joint position sense (JPS method during specific controllable circumstances very close to normal gait. Results. JPS at 15° flexion for the amputated knee was calculated to be equal to 13.91 (SD = ±4.74, and for the healthy side it was equal to 14.15 (SD = ±2.61. No statistically significant differences were detected between the amputated and the healthy limb (. Conclusions. The proprioceptive information of the stumps did not appear to be affected significantly after thigh amputation and application of artificial prosthesis when JPS at 15° was evaluated. It seems that these patients compensate the loss of the knee sensory receptors via alternative mechanisms.

  9. Influence of adjustments to amputation and artificial limb on quality of life in patients following lower limb amputation.

    Science.gov (United States)

    Sinha, Richa; van den Heuvel, Wim J A; Arokiasamy, Perianayagam; van Dijk, Jitse P

    2014-03-01

    The objectives of this study are to investigate the relationship between adjustments to amputation and artificial limb, and quality of life (QoL), and to analyse the influence of sociodemographic, medical and amputation-related factors on this relationship. Patients with unilateral and noncongenital lower limb amputation who were using artificial limb were interviewed (n=368) using structured questionnaires. The Trinity Amputation and Prosthesis Experience Scales (TAPES) were used to assess adjustments to amputation and artificial limb and the MOS Short-Form Health Survey (SF-36) was used to assess the physical (PCS) and mental (MCS) component summary of QoL. Absence of comorbidity and residual stump pain, being employed, young age, less functional restriction, being more adjusted to limitation, increased social adjustment and less restriction in athletic activity were related to better PCS scores. Absence of comorbidity and phantom limb pain, nonuse of assistive device, being more adjusted to limitation, increased social adjustment and being less functionally restricted were related to higher MCS scores. Comorbidity had a modifying effect on both PCS and MCS scores. In addition, age, being employed and residual stump pain had a modifying influence on PCS, whereas assistive device use and phantom limb pain had a modifying influence on MCS. Our findings show that TAPES subscales have a modifying effect on the associations between several background (sociodemographic and amputation characteristics) and QoL (PCS and MCS). This indicates that adjustments to amputation and artificial limb are the key determinants of QoL in individuals following lower limb amputation.

  10. Influence of adjustments to amputation and artificial limb on quality of life in patients following lower limb amputation

    NARCIS (Netherlands)

    Sinha, Richa; van den Heuvel, Wim J. A.; Arokiasamy, Perianayagam; van Dijk, Jitse P.

    2014-01-01

    The objectives of this study are to investigate the relationship between adjustments to amputation and artificial limb, and quality of life (QoL), and to analyse the influence of sociodemographic, medical and amputation-related factors on this relationship. Patients with unilateral and noncongenital

  11. Fifteen years of experience with Integral-Leg-Prosthesis: Cohort study of artificial limb attachment system.

    Science.gov (United States)

    Juhnke, Dora-Lisa; Beck, James P; Jeyapalina, Sujee; Aschoff, Horst H

    2015-01-01

    Integral-Leg-Prosthesis (ILP) is a comparatively new attachment system that allows direct skeletal docking of artificial limbs. Between January 1999 and December 2013, 69 patients with transfemoral amputation were fitted with ILPs by a single German surgeon. Device design iterations and surgical techniques evolved during these years. For the purposes of comparison, patients receiving the first two designs and procedure iterations were placed in group 1 and the patients fitted with the final design were placed in group 2. Infection rate and planned and unplanned surgical interventions were statistically compared using Fisher exact test. Data demonstrated that the high rate of stoma-associated infections seen in group 1 was dramatically reduced in group 2. Of the 39 patients with 42 implants in group 2, none had operative interventions secondary to infection. All group 2 patients remained infection-free without the use of antibiotics by following a simple but defined wound-hygiene protocol. We concluded that the final iteration of the osseointegrated intramedullary device with a low energy surface at the soft tissue and prosthesis interface allowed a biologically stable skin stoma that remained infection-free without chronic use of antibiotics. The reduction in the infection rate was attributed to the clinically based, empirically driven changes in design and surgical techniques.

  12. Fifteen years of experience with Integral-Leg-Prosthesis: Cohort study of artificial limb attachment system

    Directory of Open Access Journals (Sweden)

    Dora-Lisa Juhnke, MD

    2015-08-01

    Full Text Available Integral-Leg-Prosthesis (ILP is a comparatively new attachment system that allows direct skeletal docking of artificial limbs. Between January 1999 and December 2013, 69 patients with transfemoral amputation were fitted with ILPs by a single German surgeon. Device design iterations and surgical techniques evolved during these years. For the purposes of comparison, patients receiving the first two designs and procedure iterations were placed in group 1 and the patients fitted with the final design were placed in group 2. Infection rate and planned and unplanned surgical interventions were statistically compared using Fisher exact test. Data demonstrated that the high rate of stoma-associated infections seen in group 1 was dramatically reduced in group 2. Of the 39 patients with 42 implants in group 2, none had operative interventions secondary to infection. All group 2 patients remained infection-free without the use of antibiotics by following a simple but defined wound-hygiene protocol. We concluded that the final iteration of the osseointegrated intramedullary device with a low energy surface at the soft tissue and prosthesis interface allowed a biologically stable skin stoma that remained infection-free without chronic use of antibiotics. The reduction in the infection rate was attributed to the clinically based, empirically driven changes in design and surgical techniques.

  13. An osseointegrated human-machine gateway for long-term sensory feedback and motor control of artificial limbs.

    Science.gov (United States)

    Ortiz-Catalan, Max; Håkansson, Bo; Brånemark, Rickard

    2014-10-08

    A major challenge since the invention of implantable devices has been a reliable and long-term stable transcutaneous communication. In the case of prosthetic limbs, existing neuromuscular interfaces have been unable to address this challenge and provide direct and intuitive neural control. Although prosthetic hardware and decoding algorithms are readily available, there is still a lack of appropriate and stable physiological signals for controlling the devices. We developed a percutaneous osseointegrated (bone-anchored) interface that allows for permanent and unlimited bidirectional communication with the human body. With this interface, an artificial limb can be chronically driven by implanted electrodes in the peripheral nerves and muscles of an amputee, outside of controlled environments and during activities of daily living, thus reducing disability and improving quality of life. We demonstrate in one subject, for more than 1 year, that implanted electrodes provide a more precise and reliable control than surface electrodes, regardless of limb position and environmental conditions, and with less effort. Furthermore, long-term stable myoelectric pattern recognition and appropriate sensory feedback elicited via neurostimulation was demonstrated. The opportunity to chronically record and stimulate the neuromuscular system allows for the implementation of intuitive control and naturally perceived sensory feedback, as well as opportunities for the prediction of complex limb motions and better understanding of sensory perception. The permanent bidirectional interface presented here is a critical step toward more natural limb replacement, by combining stable attachment with permanent and reliable human-machine communication.

  14. Perceptual drifts of real and artificial limbs in the rubber hand illusion.

    Science.gov (United States)

    Fuchs, Xaver; Riemer, Martin; Diers, Martin; Flor, Herta; Trojan, Jörg

    2016-01-01

    In the rubber hand illusion (RHI), transient embodiment of an artificial hand is induced. An often-used indicator for this effect is the "proprioceptive drift", a localization bias of the real hand towards the artificial hand. This measure suggests that the real hand is attracted by the artificial hand. Principles of multisensory integration, however, rather suggest that conflicting sensory information is combined in a "compromise" fashion and that hands should rather be attracted towards each other. Here, we used a new variant of the RHI paradigm in which participants pointed at the artificial hand. Our results indicate that the perceived positions of the real and artificial hand converge towards each other: in addition to the well-known drift of the real hand towards the artificial hand, we also found an opposite drift of the artificial hand towards the real hand. Our results contradict the notion of perceptual substitution of the real hand by the artificial hand. Rather, they are in line with the view that vision and proprioception are fused into an intermediate percept. This is further evidence that the perception of our body is a flexible multisensory construction that is based on integration principles.

  15. Paré and prosthetics: the early history of artificial limbs.

    Science.gov (United States)

    Thurston, Alan J

    2007-12-01

    There is evidence for the use of prostheses from the times of the ancient Egyptians. Prostheses were developed for function, cosmetic appearance and a psycho-spiritual sense of wholeness. Amputation was often feared more than death in some cultures. It was believed that it not only affected the amputee on earth, but also in the afterlife. The ablated limbs were buried and then disinterred and reburied at the time of the amputee's death so the amputee could be whole for eternal life. One of the earliest examples comes from the 18th dynasty of ancient Egypt in the reign of Amenhotep II in the fifteenth century bc. A mummy in the Cairo Museum has clearly had the great toe of the right foot amputated and replaced with a prosthesis manufactured from leather and wood. The first true rehabilitation aids that could be recognized as prostheses were made during the civilizations of Greece and Rome. During the Dark Ages prostheses for battle and hiding deformity were heavy, crude devices made of available materials - wood, metal and leather. Such were the materials available to Ambroise Paré who invented both upper-limb and lower-limb prostheses. His 'Le Petit Lorrain', a mechanical hand operated by catches and springs, was worn by a French Army captain in battle. Subsequent refinements in medicine, surgery and prosthetic science greatly improved amputation surgery and the function of prostheses. What began as a modified crutch with a wooden or leather cup and progressed through many metamorphoses has now developed into a highly sophisticated prosthetic limb made of space-age materials.

  16. Effect of amputation level on the stress transferred to the femur by an artificial limb directly attached to the bone.

    Science.gov (United States)

    Newcombe, L; Dewar, M; Blunn, G W; Fromme, P

    2013-12-01

    Attachment of an artificial limb directly to the skeleton has a number of potential benefits and the technique has been implemented for several amputation sites. In this paper the transfer of stress from an external, transfemoral prosthesis to the femur during normal walking activity is investigated. The stress distribution in the femur and at the implant-bone interface is calculated using finite element analysis for the 3D geometry and inhomogeneous, anisotropic material properties obtained from a CT scan of a healthy femur. Attachment of the prosthetic leg at three different levels of amputation is considered. Stress concentrations are found at the distal end of the bone and adjacent to the implant tip and stress shielding is observed adjacent to the implant. It is found that the stress distribution in the femur distal to the epiphysis, where the femur geometry is close to cylindrical, can be predicted from a cylindrical finite element model, using the correct choice of bone diameter as measured from a radiograph. Proximal to the lesser trochanter the stress decreases as the femur geometry diverges significantly from a cylinder. The stress concentration at the distal, resected end of the bone is removed when a collared implant is employed. These findings form the basis for appropriate settings of an external fail-safe device to protect the bone from excessive stress in the event of an undue load.

  17. Current situation of artificial lower limbs of human body%人体下肢假肢的现代发展状况

    Institute of Scientific and Technical Information of China (English)

    张更林; 金宝士; 张宇光

    2004-01-01

    介绍了人体下肢假肢技术的发展历史、研究现状、应用情况及未来的发展状况.纵观假肢发展的趋势,主要以新材料、传动方式以及智能化等方面的研究为主.新材料的应用主要以高强度、低质量的一类材料为主,如钛合金、碳素纤维以及其他复合材料;而新技术则以液压、气压等传动方式;控制方面则趋向于智能控制等.着重阐述了现代假肢技术的构成及假肢膝关节的控制技术.%This paper reviews technological evolution, current researches and applications of artificial lower limbs for human, and proposes the trends of them. Developments of artificial limbs are mainly focus on researches on new materials, driving way and intelligentizing. New materials applied are mainly high strength as well as light mass materials, such as titanium alloys, carbon fiber composites and other composites. The new technologies include the barometric control unit, the hydraulic control unit and intellectual control,etc.. Modem module technology and control technology of knee joint for artificial limb are also reviewed.

  18. Estimation of forces at the interface between an artificial limb and an implant directly fixed into the femur in above-knee amputees.

    Science.gov (United States)

    Stephenson, Paul; Seedhom, Bahaa B

    2002-01-01

    This article describes the method used for estimating the forces and moments, acting during locomotion, at the interface between an artificial leg and an implant directly fixed into the femur, in above-knee amputees. Twelve transfemoral amputees completed a predefined gait assessment during which kinetic (ground reaction loads and torque) and kinematic (limb orientation) gait data were recorded. A developed mathematical model enabled the ground reaction forces to be translated to the level of amputation. It is assumed that the loads calculated at the stump-socket interface would approximate those experienced by the proposed implant. The longitudinal force and the moment in the sagittal plane were the two most significant loads at the stump. These data were essential to obtain to facilitate the analysis of stress arising at the implant-bone interface that has been subsequently undertaken.

  19. 电子假肢肌电信号源的改进%Enhancement of myoelectric signal of electronic artificial limb

    Institute of Scientific and Technical Information of China (English)

    董震; 顾玉东; 成效敏; 张凯莉; 朱艺

    2001-01-01

    Objective To provide myoelectric signal of electronic artificial limb via examination and assessment of the myoelectric signals given by upper extremity muscles in light contraction. Methods 60 normal human adults were included in the study. Myoelectric signals of four pairs of antagonists of the upper limb (forearm flexors - extensors, brachial biceps brachii - triceps brachii, deltoid - pectoralis major, infraspinatus - latissimus dorsi) in light contraction were recorded by using surface electrode. Frequency and amplitude of the signals was analyzed. Results  When the four pairs of antagonists were in light contraction, the frequency and amplitude of the myoelectric signals centralized in 85 - 150 Hz and 220 - 250 uV respectively. Conclusions The artificial limb equipped with myoelectric signals with frequency of 85 - 150 Hz and amplitude of 220 - 250 uV can increase real time of the myoelectric signal and practicability.%目的通过对上肢肌群肌肉轻收缩时肌电信号的检测与分析,提供电子假肢信号源。方法对60例正常人,用表面电极分别测定上肢四组拮抗肌(前臂屈肌——前臂伸肌,肱二头肌——肱三头肌,三角肌——胸大肌,冈下肌——背阔肌)在轻收缩时的肌电信号,并分析其频率与波幅。结果上肢四组拮抗肌在肌肉轻收缩时,肌电信号频率集中在85 ~ 150 Hz,波幅集中在220 ~ 250 V。结论采用频率85 ~ 150 Hz,波幅220 ~ 250 V的肌电信号作为电子假肢信号源,可提高肌电信号实时性及假肢的实用性。

  20. 推拿配合人工单下肢牵引治疗腰椎间盘突出症%Manipulation Combined with Artificial Single Lower Limb Traction in the Treatment of Lumbar Disc Herniation

    Institute of Scientific and Technical Information of China (English)

    李宏龙; 平晓慧

    2013-01-01

    Objective:To observe the clinical effect of artificial single lower limb traction combined with manipulation in the treatment of lumbar disc herniation. Methods:96 patients were randomly divided into observation group and control group. Observation group was treated with artificial sin-gle lower limb traction combined with manipulation, while control group was treated with double lower limb hammer traction. The clinical efficacy was compared between the two groups. Results:The total effective rate was 95.83%in observation group and 85.42%in control group with signifi-cant difference (P<0.05). The clinical effect in the observation group was better than that of control group. Conclusion:Artificial single lower limb traction is superior to traditional double lower limb hammer traction in the treatment of lumbar disc herniation.%目的:观察人工单下肢牵引法配合推拿治疗腰椎间盘突出症的疗效。方法:将96例患者随机分为观察组和对照组,观察组采用人工单下肢牵引法配合推拿治疗;对照组采用双下肢重锤牵引法配合推拿治疗,比较两组临床疗效。结果:观察组总有效率为95.83%,高于对照组的85.42%(P<0.05)。结论:人工单下肢牵引法治疗腰椎间盘突出症疗效优于传统的双下肢重锤牵引法。

  1. Flap repair for vascular prosthesis exposure after artificial blood vessel bypass surgery for critical limb ischemia%皮瓣重建修复下肢动脉旁路移植术后人工血管外露

    Institute of Scientific and Technical Information of China (English)

    吴巍巍; 吴昊; 曾昂; 白明; 曾嵘; 陈宇; 刘昌伟

    2013-01-01

    Objective To investigate the effectiveness of flap repair for vascular prosthesis exposure after the artificial blood vessel bypass surgery for critical limb ischemia.Methods From August 2007 to December 2011,bypass surgery with vascular prosthetic grafts were performed in 192 patients with critical limb ischemia.Five patients among them (2.6%) suffered from vascular prosthesis exposure 6 to 13 days after the previous surgery,including 4 males and 1 female,with a median age of 68 years (arranged from 52 to 81 years).The surgical managements included surgical debridement and local flap or transferred muscle-cutaneous flap repair to preserve the prosthetic vascular grafts.Three patients underwent Z-plasty with local flap repair,while 2 patients underwent transferred rectus abdominis or rectus femoris muscle flap repair of the wounds.Results After the surgery,prosthetic vascular graft was successfully preserved in 4 of the 5 cases with first intention healing.At a median follow-up of 38 months (arranged from 5 to 57 months),all the 4 limbs were salvaged with patent of the prosthetic grafts.One flap failed to heal and the prosthetic graft had to be removed due to infection and hemorrhage.An above-knee-amputation was performed due to severe limb ischemia.Conclusions The vascular prosthesis exposure is often a disaster after artificial blood vessel bypass surgery for critical limb ischemia.Local flap or transferred muscle-cutaneous flap repair is an effective surgical management to salvage the exposed graft and the affected limb.%目的 探讨皮瓣重建技术修复因重症下肢缺血行人工血管旁路移植术后人工血管外露的可行性.方法 回顾性分析2007年8月至201 1年12月诊治的192例下肢人工血管旁路移植术后患者,其中5例(2.6%)在前次术后6~13d发生人工血管外露,包括男性4例,女性1例,年龄52~81岁,中位年龄68岁.外科处理主要包括局部清创及保留移植物的任意皮

  2. Limb anomalies

    DEFF Research Database (Denmark)

    Gurrieri, Fiorella; Kjær, Klaus Wilbrandt; Sangiorgi, Eugenio

    2002-01-01

    In this review we describe the developmental mechanisms involved in the making of a limb, by focusing on the nature and types of interactions of the molecules that play a part in the regulation of limb patterning and characterizing clinical conditions that are known to result from the abnormal...... function of these molecules. The latter subject is divided into sections dealing with syndromal and nonsyndromal deficiencies, polydactylies, and brachydactylies. Conditions caused by mutations in homeobox genes and fibroblast growth factors and their receptor genes are listed separately. Since the process...... of limb development has been conserved for more than 300 millions years, with all the necessary adaptive modifications occurring throughout evolution, we also take into consideration the evolutionary aspects of limb development in terms of genetic repertoire, molecular pathways, and morphogenetic events....

  3. Computed-torque method for the control of a 2 DOF orthosis actuated through pneumatic artificial muscles: a specific case for the rehabilitation of the lower limb

    CERN Document Server

    Prattico, Flavio; Yamamoto, Shin-ichiroh

    2014-01-01

    In this paper we give a new control model based on the so called computed-torque method for the control of a 2 degrees of freedom orthosis for the rehabilitation of the lower limb, the AIRGAIT exoskeleton's leg orthosis. The actuation of the AIRGAIT is made through self-made pneumatic muscles. For this reason this work starts with the static and dynamic characterization of our pneumatic muscles. The followed approach is based on the analytical description of the system. For this, we describe the pneumatic muscles behaviour with an easy-invertible polynomial fit function in order to model its non-linear trend. We give a geometrical model of the mechanical system to compute the length between the attachments of the pneumatic muscles to the structure for every angles assumed by the two joints. We evaluate through Newton-Euler equation the couples at the joints for each values of the angles. At last we show some validation tests in order to characterize the functioning of the proposed control model on the actuati...

  4. Research on rigid polyurethane foam used in the production of artificial limbs%假肢制作中用硬质聚氨酯泡沫塑料的研究

    Institute of Scientific and Technical Information of China (English)

    樊守贞

    2015-01-01

    In accordance with the requirements of the prosthetic production process ,we studied the effect of formulation and process conditions on the properties of the rigid polyurethane foam which applied to the manufacture of artificial limbs .The research showed that :when the mass ratio of A ,B component is 1∶1 .45 ,50% compression pressure of the rigid polyurethane foam is 50 .4kg/cm2 ,and the yield pressure up to 28 .3kg/cm2 .Furthermore ,the rigid polyure‐thane foam has good temperature‐resisting and pressure‐resisting and is easy to use ,surface roughness is in line with the requirements of vacuum molding process after repalring .%根据假肢制作工艺的要求,对应用于假肢制作的硬质聚氨酯泡沫塑料的配方、工艺条件等进行了研究,其结果表明:当A ,B组分质量比为1∶1.45时,压缩50%时压强达50.4kg/cm2,屈服时压强达28.3kg/cm2。使用方便,其耐压、耐温、修型后的表面平整度符合真空成型工艺要求。

  5. Pneumatic Feedback for Wearable Lower Limb Exoskeletons Further Explored

    NARCIS (Netherlands)

    Muijzer-Witteveen, Heidi; Guerra, Francisco; Sluiter, Victor; Kooij, van der Herman; Bello, Fernando; Kajimoto, Hiroyuki; Visell, Yon

    2016-01-01

    For optimal control of wearable lower limb exoskeletons the sensory information flow should also be (partly) restored, especially when the users are Spinal Cord Injury subjects. Several methods, like electrotactile or electromechanical vibrotactile stimulation, to provide artificial sensory feedback

  6. Upper limb arterial thromboembolism

    DEFF Research Database (Denmark)

    Andersen, L V; Lip, Gregory Y.H.; Lindholt, J S;

    2013-01-01

    The aim of this review is to focus on risk factors, risk-modifying drugs and prognosis for upper limb arterial thromboembolism, and the relationship between upper limb arterial thromboembolism and atrial fibrillation (AF).......The aim of this review is to focus on risk factors, risk-modifying drugs and prognosis for upper limb arterial thromboembolism, and the relationship between upper limb arterial thromboembolism and atrial fibrillation (AF)....

  7. 人工真皮结合自体表皮治疗四肢皮肤软组织缺损的应用研究%Application study of artificial dermis combined with the auto-epidermis transplantation for treatment of skin and soft tissue defects limbs

    Institute of Scientific and Technical Information of China (English)

    陈朗; 周国富

    2012-01-01

    目的:评价人工真皮结合自体表皮修复四肢皮肤软组织缺损的临床疗效.方法:本组共10例四肢皮肤软组织缺损患者,其中肌腱外露3例,骨外露1例.一期清创后移植人工真皮,2~3周后待创面良性新生肉芽组织生长,二期移植自体薄层皮片.观察植皮皮片存活情况,外观,质地,瘢痕生长情况,评估临床效果.结果:10例患者所植皮片全部存活,外观均良好,无明显瘢痕.结论:采用人工真皮结合自体表皮移植治疗四肢皮肤软组织缺损操作简便,创面愈合良好,并可在合并肌腱及骨外露创面应用.%Objective To evaluate the curative effects of artificial dermis combined with the auto-epidermis transplantation for treatment of skin and soft tissue defects of limbs. Methods A total of 10 cases of patients with skin and soft tissue defect limbs, including 3 cases with tendon exposure, 1 case with bone exposure. All the patients were performed debridement and artificial dermis firstly for two to three weeks, when the local granulation tissue grew well, followed by split thickness autoskin transplantation. The survival of artificial dermis and split -thickness skin, appearance, texture, scar were observed, evaluate clinical effect. Results All cases had good coverage of wounds, postoperative follow-up of three months, recheck outcome showed skin graft healing was excellent and no obvious skin scar. Conclusion Repair of skin and soft tissue defects with artificial dermis had high quality of wounds healing, simple operation, and can be applied in wounds with tendons and bones exposed.

  8. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  9. LDTk: Limb Darkening Toolkit

    CERN Document Server

    Parviainen, Hannu

    2015-01-01

    We present a Python package LDTk that automates the calculation of custom stellar limb darkening (LD) profiles and model-specific limb darkening coefficients (LDC) using the library of PHOENIX-generated specific intensity spectra by Husser et al. (2013). The aim of the package is to facilitate analyses requiring custom generated limb darkening profiles, such as the studies of exoplanet transits--especially transmission spectroscopy, where the transit modelling is carried out for custom narrow passbands--eclipsing binaries (EBs), interferometry, and microlensing events. First, LDTk can be used to compute custom limb darkening profiles with uncertainties propagated from the uncertainties in the stellar parameter estimates. Second, LDTk can be used to estimate the limb-darkening-model specific coefficients with uncertainties for the most common limb-darkening models. Third, LDTk can be directly integrated into the log posterior computation of any pre-existing modelling code with minimal modifications. The last a...

  10. Artificial Intelligence.

    Science.gov (United States)

    Waltz, David L.

    1982-01-01

    Describes kinds of results achieved by computer programs in artificial intelligence. Topics discussed include heuristic searches, artificial intelligence/psychology, planning program, backward chaining, learning (focusing on Winograd's blocks to explore learning strategies), concept learning, constraint propagation, language understanding…

  11. Upper Limb Exoskeleton

    NARCIS (Netherlands)

    Rusak, Z.; Luijten, J.; Kooijman, A.

    2015-01-01

    The present invention relates a wearable exoskeleton for a user having a torso with an upper limb to support motion of the said upper limb. The wearable exoskeleton comprises a first fixed frame mountable to the torso, an upper arm brace and a first group of actuators for moving the upper arm brace

  12. Mobility of people with lower limb amputations: scales and questionnaires: a review

    OpenAIRE

    Rommers, G. M.; Groothoff, J. W.; Eisma, W.H.

    2001-01-01

    Objective and design: A systematic literature review to compare mobility scales used for lower limb amputees. A literature search was carried out by computerized search of biomedical literature including Medline and Embase. The studies included were published between 1978 and 1998 and including the following keywords: amputation, artificial limbs, prosthesis, lower limb, activities of daily living, mobility. Results: Thirty-five studies were identified; 19 had a measurement of separate levels...

  13. 特制人工膝关节假体在骨肉瘤合并病理骨折保肢治疗中的应用%Application of custom-manufactured artificial total knee prosthesis in limb salvage surgery for patients with a pathologic fracture in osteosarcoma

    Institute of Scientific and Technical Information of China (English)

    李福生; 徐绍年; 黄海; 杜振广; 王亮

    2014-01-01

    BACKGROUND:Osteosarcoma combined with pathological fracture was often treated by amputation. With clinical application of neoadjuvant chemotherapy and improvement of technology and material of the prosthesis, the limbs of patients with osteosarcoma combined with pathological fracture were reserved. OBJECTIVE:To evaluate the effect of the application of custom-manufactured artificial total knee prosthesis replacement in limb salvage treatment for patients with osteosarcoma combined with pathological fracture. METHODS:A total of 11 patients with pathological fracture with osteosarcoma located in adjacent knee Joint were enrol ed from June 2002 to September 2012. In accordance with individual condition of the patient, limb salvage treatment was designed for knee prosthesis for a tumor. Fol ow-up results were retrospectively analyzed. There were six males (54.5%) and five females (45.5%) and their age ranged from 11 to 50 years old with an average age of 25.4 years old. Onset regions:seven tumors were located in the distal femur and four tumors were in the proximal tibia. Al patients received neoadjuvant chemotherapy, and limb salvage treatment with custom-manufactured artificial knee prosthesis. The fol ow up was performed for 9 to 105 months. RESULTS AND CONCLUSION:In 11 patients after prosthesis replacement, the regional recurrence rates were 18%, lung metastasis rates were 36%. The five-year survival rate was 58%. Four patients developed lung metastases and died in 9 to 24 months postoperatively. During the last fol ow-up, Enneking score of the affected limbs was 11 to 30 points, averagely 23.3 points, with an excellent and good rate of 82%. Results indicated that combined with neoadjuvanet chemotherapy, the application of custom-manufactured artificial total knee prosthesis replacement in the treatment of osteosarcoma located in adjacent knee joint and pathological fracture achieved an ideal outcomes of the limb salvage treatment in the near future. The lone

  14. Out on a Limb: Investigating the Anatomy of Tree Limbs

    Science.gov (United States)

    Shaw, Edward L.

    2008-01-01

    The author presents several upper elementary science activities involving tree limbs that were collected after severe weather conditions. The activities involved 3rd-grade students arranging tree limb pieces in the correct order from the trunk to the tip of the limb, measuring the pieces, determining the age of a tree limb by its rings,…

  15. Phantom limb pain

    Science.gov (United States)

    ... Philadelphia, PA: Elsevier; 2015:chap 54. Nikolajsen L, Springer JS, Haroutiunian S. Phantom limb pain. In: Benzon HT, ... medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- ...

  16. Limb regeneration: a new development?

    Science.gov (United States)

    Nacu, Eugen; Tanaka, Elly M

    2011-01-01

    Salamander limb regeneration is a classical model of tissue morphogenesis and patterning. Through recent advances in cell labeling and molecular analysis, a more precise, mechanistic understanding of this process has started to emerge. Long-standing questions include to what extent limb regeneration recapitulates the events observed in mammalian limb development and to what extent are adult- or salamander- specific aspects deployed. Historically, researchers studying limb development and limb regeneration have proposed different models of pattern formation. Here we discuss recent data on limb regeneration and limb development to argue that although patterning mechanisms are likely to be similar, cell plasticity and signaling from nerves play regeneration-specific roles.

  17. Artificial blood

    Directory of Open Access Journals (Sweden)

    Sarkar Suman

    2008-01-01

    Full Text Available Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  18. Artificial blood.

    Science.gov (United States)

    Sarkar, Suman

    2008-07-01

    Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  19. 基于中枢模式产生器的主动式智能踝关节控制的研究%Study on the Control of Dynamic Artificial Limb Ankle Based on Central Pattern Generator

    Institute of Scientific and Technical Information of China (English)

    郭欣; 徐彩玉; 李明月; 苏龙涛

    2014-01-01

    In order to obtain the normal gait for the prosthesis-carrier with the change of external environment and gait,we designed a model of dynamic ankle prosthesis and control system and introduced the strategy of central pattern generator (CPG) about the moving trail of dynamic ankle prosthesis.The dynamic parts,which are incorporated in the model of dynamic ankle prosthesis,provide power in order to have anthropic function and character.The tool of Matlab/simulink was used to simulate the strategy.The simulation results showed that the strategy of CPG learning control in this study was effective and could track the reference trail rapidly and fit the moving trail of a person's normal limb.It can make the prosthetic timely regulation and action,enhance the prosthetic intelligence.It has important practical value for intelligent prosthesis development based on this analysis of technology.%为了使主动式踝关节假肢携带者能更好地根据外部环境和步态的变化实现假肢自然行走,设计了主动式智能踝关节假肢的机械结构和控制系统,提出了主动式踝关节假肢运动轨迹的中枢模式产生器(CPG)控制策略.主动式踝关节假肢通过动力机构为人体提供了运动动力,可实现人体运动的主要功能和特性.通过Matlab/simulink仿真,有效验证了基于生物中枢模式产生器控制机制的主动式踝关节的运动控制方法,能够使主动式踝关节假肢的输出轨迹准确快速地跟踪期望轨迹.因此该主动式踝关节假肢能实现及时调节和动作,智能性增强,同时本文提出的该项技术对智能假肢的发展具有重要的实用价值.

  20. Design and control of hybrid actuation lower limb exoskeleton

    Directory of Open Access Journals (Sweden)

    Hipolito Aguilar-Sierra

    2015-06-01

    Full Text Available In this article, two types of actuators are applied for a lower limb exoskeleton. They are DC motors with the harmonic drive and the pneumatic artificial muscles. This combination takes advantages of both the harmonic drive and the pneumatic artificial muscle. It provides both high accuracy position control and high ratio of strength and weight. The shortcomings of the two actuators are overcome by the hybrid actuation, for example, low control accuracy and modeling difficult of pneumatic artificial muscle, compactness, and structural flexibility of DC motors. The design and modeling processes are discussed to show the proposed exoskeleton can increase the strength of human lower limbs. Experiments and analysis of the exoskeleton are given to evaluate the effectiveness of the design and modeling.

  1. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  2. Artificial urushi.

    Science.gov (United States)

    Kobayashi, S; Uyama, H; Ikeda, R

    2001-11-19

    A new concept for the design and laccase-catalyzed preparation of "artificial urushi" from new urushiol analogues is described. The curing proceeded under mild reaction conditions to produce the very hard cross-linked film (artificial urushi) with a high gloss surface. A new cross-linkable polyphenol was synthesized by oxidative polymerization of cardanol, a phenol derivative from cashew-nut-shell liquid, by enzyme-related catalysts. The polyphenol was readily cured to produce the film (also artificial urushi) showing excellent dynamic viscoelasticity.

  3. Prediction on Lower Limbs' Joint Torques Using Artificial Neural Network during Vertical Jumps%神经网络模型预测纵跳时下肢关节内力矩

    Institute of Scientific and Technical Information of China (English)

    刘宇; 史世民; 钟运健

    2008-01-01

    关节肌肉力矩在生物力学研究中是一个非常有价值且应用性颇广的参数.要获得关节力矩数值,需同步测量运动学和地面反作用力参数,并通过逆向动力学(Inversce Dynamic)过程方能求得.目的在于建立推估两种纵跳:直立(Counter-Movement Jump,CMJ)和蹲位(Squat Jump,SJ)时下肢各关节力矩的人工神经网络(artificial ncural network,ANN),通过输入相对较容易测得的地面反作用力参数,推估下肢关节力矩(踝、膝、髋).以10位男性运动员为受试者,在测力台上完成两种纵跳,其所测得的地面反作用力参数作为神经网络模型的输入数据,以下肢各关节力矩为输出数据.经过网络优化后,所求得的最佳神经网络模型为"5-10-3模型"(即输入层有5个神经元;隐藏层为1层,有10个神经元;输出层有3个神经元).该模型所推估出的下肢各关节力矩极值相对误差均小于6%,与实测值的相关系数高达0.95以上,且在推估关节力矩曲线形态与角冲量方面的表现也十分良好,显示通过神经网络以地面反作用力来推估下肢各关节力矩的方法是准确和可行的.

  4. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  5. Natural - synthetic - artificial!

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  6. Limb salvage surgery

    Directory of Open Access Journals (Sweden)

    Dinesh Kadam

    2013-01-01

    Full Text Available The threat of lower limb loss is seen commonly in severe crush injury, cancer ablation, diabetes, peripheral vascular disease and neuropathy. The primary goal of limb salvage is to restore and maintain stability and ambulation. Reconstructive strategies differ in each condition such as: Meticulous debridement and early coverage in trauma, replacing lost functional units in cancer ablation, improving vascularity in ischaemic leg and providing stable walking surface for trophic ulcer. The decision to salvage the critically injured limb is multifactorial and should be individualised along with laid down definitive indications. Early cover remains the standard of care, delayed wound coverage not necessarily affect the final outcome. Limb salvage is more cost-effective than amputations in a long run. Limb salvage is the choice of procedure over amputation in 95% of limb sarcoma without affecting the survival. Compound flaps with different tissue components, skeletal reconstruction; tendon transfer/reconstruction helps to restore function. Adjuvant radiation alters tissue characters and calls for modification in reconstructive plan. Neuropathic ulcers are wide and deep often complicated by osteomyelitis. Free flap reconstruction aids in faster healing and provides superior surface for offloading. Diabetic wounds are primarily due to neuropathy and leads to six-fold increase in ulcerations. Control of infections, aggressive debridement and vascular cover are the mainstay of management. Endovascular procedures are gaining importance and have reduced extent of surgery and increased amputation free survival period. Though the standard approach remains utilising best option in the reconstruction ladder, the recent trend shows running down the ladder of reconstruction with newer reliable local flaps and negative wound pressure therapy.

  7. Limb salvage surgery.

    Science.gov (United States)

    Kadam, Dinesh

    2013-05-01

    The threat of lower limb loss is seen commonly in severe crush injury, cancer ablation, diabetes, peripheral vascular disease and neuropathy. The primary goal of limb salvage is to restore and maintain stability and ambulation. Reconstructive strategies differ in each condition such as: Meticulous debridement and early coverage in trauma, replacing lost functional units in cancer ablation, improving vascularity in ischaemic leg and providing stable walking surface for trophic ulcer. The decision to salvage the critically injured limb is multifactorial and should be individualised along with laid down definitive indications. Early cover remains the standard of care, delayed wound coverage not necessarily affect the final outcome. Limb salvage is more cost-effective than amputations in a long run. Limb salvage is the choice of procedure over amputation in 95% of limb sarcoma without affecting the survival. Compound flaps with different tissue components, skeletal reconstruction; tendon transfer/reconstruction helps to restore function. Adjuvant radiation alters tissue characters and calls for modification in reconstructive plan. Neuropathic ulcers are wide and deep often complicated by osteomyelitis. Free flap reconstruction aids in faster healing and provides superior surface for offloading. Diabetic wounds are primarily due to neuropathy and leads to six-fold increase in ulcerations. Control of infections, aggressive debridement and vascular cover are the mainstay of management. Endovascular procedures are gaining importance and have reduced extent of surgery and increased amputation free survival period. Though the standard approach remains utilising best option in the reconstruction ladder, the recent trend shows running down the ladder of reconstruction with newer reliable local flaps and negative wound pressure therapy.

  8. Limb girdle muscular dystrophies

    DEFF Research Database (Denmark)

    Vissing, John

    2016-01-01

    PURPOSE OF REVIEW: The aim of the study was to describe the clinical spectrum of limb girdle muscular dystrophies (LGMDs), the pitfalls of the current classification system for LGMDs, and emerging therapies for these conditions. RECENT FINDINGS: Close to half of all LGMD subtypes have been...

  9. Surgical treatment of traumatic lower limb pseudoaneurysm

    Institute of Scientific and Technical Information of China (English)

    Pan Zhongjie; Zhang Hua; Li Li; Jia Yutao; Tian Rong

    2014-01-01

    Objective:To summarize our experience in surgical treatment of traumatic lower limb pseudoaneurysm.Methods:Twenty patients with traumatic lower limb pseudoaneurysm were surgically treated in our department from January 2007 to January 2012.The treatment protocols included interventional covered-stent placement (10 cases),spring coil embolization (2 cases),and surgical operation (8 cases).Surgical operations included pseudoaneurysm repair (2 cases),autologousvein transplantation (1 case),and artificial-vessel bypass graft (5 cases).Results:All the patients were successfully treated without aggravating lower limb ischemia.Pseudoaneurysm disappeared after treatment.A surgical operation is suitable to most pseudoaneurysms,but its damage is relatively obvious and usually leads to more bleeding.It also requires a longer operating time.Compared to a surgical operation,interventional therapy is less traumatic and patients usually have a quicker recovery (P<0.05).All patients were followed up once per month for 12-36 months by color Doppler ultrasound examination.There were no cases of pseudoaneurysm recurrence.Conclusion:Both surgical operation and interventional therapy are safe and effective in the treatment of pseudoaneurysm.

  10. Artificial Intelligence

    CERN Document Server

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  11. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containin......Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie...

  12. 单侧初次人工髋关节置换患者康复期下肢关节的运动状况研究%Study of lower limbs joints movement of patients with unilateral and primary artificial hip replacement in con-valescence

    Institute of Scientific and Technical Information of China (English)

    龙术民; 杨陈诚; 杜勇

    2015-01-01

    Objective To explore the lower limbs joints movement of patients with unilateral and primary artificial hip replacement in convalescence. Methods 100 cases of patients with unilateral and primary artificial hip replacement in convalescence were chosen as the ob-servation group,while 100 cases of matched healthy subjects were included as the control groups. The three-dimensional kinematics and mo-tion of lower extremities were monitored. Results The difference in operated knee flexion,operated ankle planter flexion and operated hip flexion of the observation group and the observation group were statistically significant(P<0. 05). The difference in the joint angle peak of hip backward extension of sagittal section,hip adduction of frontal plane,knee adduction of frontal plane,ankle adduction and outreach of frontal plane,hip internal rotation and extorsion of horizontal plane,ankle rotation and extorsion of horizontal plane in two groups were statisti-cally significant(P<0. 05). Conclusion There are abnormal prosthetic joint movement,limited range of operated movement in patients with unilateral and primary artificial hip replacement in convalescence,and coterminous kinematic chains appear compensatory changes,it should strengthen the muscle exercises of operated hip.%目的:探究单侧初次人工髋关节置换康复期患者下肢关节的运动状况。方法选择100例单侧初次人工髋关节置换康复期患者作为观察组,纳入100例相匹配的健康体检者作为对照组,均进行下肢三维运动学与动力学监测。结果观察组患者术侧膝关节、踝关节、髋关节屈曲力矩峰值与对照组右下肢相比,差异有统计学意义(P<0.05)。观察组患者术侧矢状面髋后伸、额状面髋内收、额状面膝内收、额状面踝内收和外展、水平面髋内旋和外旋、水平面踝内旋和外旋等关节角度峰值分别与对照组右下肢相比,差异有统计学意义(P<0.05)。结论单侧初

  13. Lower limb landmine injuries.

    Science.gov (United States)

    Necmioglu, S; Subasi, M; Kayikci, C; Young, D B

    2004-04-01

    The medical records of 186 patients seeking treatment for landmine injuries in the authors' region between 1993 and 2001 were evaluated. Of these patients 13 died of accompanying complications. Ten (10) patients with general body trauma and upper limb trauma were excluded from the study. Of 163 patients with lower-limb injuries included in the study, 21 with traumatic amputation underwent surgical amputation at different levels. Patients without traumatic amputation were divided into 2 groups. There were 41 patients (29%) in Group I who were treated by limb salvage procedures. Treatments used in Group I including wound debridement, tendon repair, skin approximation, minimal osteosynthesis, external fixation of long bones and secondary wound coverage. In Group II, there were 101 patients (71%) with primary amputation. Trans-tibial amputation was performed in 52 cases (51.4%), ankle disarticulation in 24 (23.7%), trans-femoral amputation in 9 (8.9%), partial foot amputation in 8 (7.9%), knee disarticulation in 7 (6.9%) and hip disarticulation in 1 case. In Group I, there was infection in 21 patients (51.2%), revision in 27 (65.8%), and amputation in 15 (36.5%). In Group II, there was infection in 28 patients (27.7%), revision in 17 (16.8%), and amputation at a higher level in 8 (7%). In crush injuries such as those resulting from landmines, soft tissue, vascular, and neurological assessment must be performed with utmost care. Even so, the desired success in interventions intended to save a limb is complicated by a high infection rate, soft tissue complications, and high revision amputation rates. Therefore, a decision to amputate in the early term based on an accurate preoperative assessment is crucial.

  14. Experimental study on the pathogenesis of deep venous thrombosis in lower limbs following artificial total hip replacement%人工全髋关节置换术后下肢深静脉血栓形成原因的实验观察

    Institute of Scientific and Technical Information of China (English)

    杨景武; 史晓林

    2005-01-01

    不良事件及副反应:3例出血达1 000 mL.为充分暴露手术视野,用拉钩阻挡肌肉等组织,即造成血管的长期积压,血流迟缓.结论:人工全髋置换术易损伤髋臼血管内壁,从而导致血流减慢和血小板聚集,最终促使血栓形成.同时术中失血多,使血液黏稠导致血栓形成.根据易损伤区及安全区模式图可知,下肢深静脉血栓是可以减少的.%BACKGROUND:Deep venous thrombosis has already been recognized as an important serious postoperative complication because it can cause fatal pulmonary embolism and long-term deep venous dysfunction. With the constant development of artificial joint operation and the popularization of such surgery, much attention has been paid to the formation of deep venous thrombosis following artificial joint replacement.OBJECTIVE: To observe the anatomical property of acetabular surrounding arteries and veins, as well as their injury during total hip replacement,so as to explore the cause of deep venous thrombosis in lower limbs following artificial total hip replacement.DESIGN: Single sample observation and before-after self-control.SETTING: Gross anatomy was carried out in the anatomical laboratory of the Medical School of Huzhou Teachers' College; total hip replacement was carried out in the Orthopedic Department, Xinhua Hospital of Zhejiang Traditional Chinese Medicine College.PARTICIPANTS: Pelvic samples were collected from 60 normal adult corpuses (30 from men and 30 from women); meanwhile, 30 patients (18 males and 12 females) received total hip replacement in the Orthopedic Department of Xinhua Hospital, Zhejiang Traditional Chinese Medicine College, between March 2002 and August 2003.METHODS: Gross anatomy was carried out at the anatomical laboratory in the Medical School of Huzhou Teachers' College between March and May 2003. The running course of bilateral external iliac artery and vein, as well as the relationship between the branches of femoral artery and vein and acetabulum were

  15. Artificial ribonucleases.

    Science.gov (United States)

    Morrow, J R

    1994-01-01

    Many inorganic and organic compounds promote the reactions catalyzed by RNase A. Both the transesterification step, where a 2',3'-cyclic phosphate is formed with concomitant cleavage of RNA, and the hydrolysis step, where the 2',3'-cyclic phosphate is converted to a phosphate monoester, may be mimicked with compounds that are readily synthesized in the laboratory. Electrophilic activation of the phosphate ester and charge neutralization are generally important means by which artificial RNases promote phosphate diester displacement reactions. Several artificial RNases operate by a bifunctional general acid/general base mechanism, as does RNase A. Provision of an intramolecular nucleophile appears to be an important pathway for metal complex promoted phosphate diester hydrolysis. In contrast to the successful design of compounds that promote the reactions catalyzed by RNase A, there are no artificial nucleases to date that will cleave the 3' P-O bond of RNA or hydrolyze an oligonucleotide of DNA. Artificial RNases based on both metal complexes and organic compounds have been described. Metal complexes may be particularly effective catalysts for both transesterification and hydrolysis reactions of phosphate diesters. Under physiological conditions (37 degrees C and neutral pH), several metal complexes catalyze the transesterification of RNA. Future work should involve the development of metal complexes which are inert to metal ion release but which maintain open coordination sites for catalytic activity. The design of compounds containing multiple amine or imidazole groups that may demonstrate bifunctional catalysis is a promising route to new artificial RNases. Further design of these compounds and careful placement of catalytic groups may yield new RNase mimics that operate under physiological conditions. The attachment of artificial RNases to recognition agents such as oligodeoxynucleotides to create new sequence-specific endoribonucleases is an exciting field of

  16. Biotic - Abiotic Interface Between they Body and the Artificial Limb

    Science.gov (United States)

    2008-09-29

    stability, and biocompatibility, titanium is a commonly used material in dental and orthopedic applications (Pohler 2000). Its excellent biocompatibility...administrated inhaled anethesia using isofluorane. Pre-emptive analgesia was given 30 minutes before the procedure as a subcutaneous injection of buprenorphine...155–170. Bränemark PI, Breine U, Adell R, and Breine U. Intra-osseous anchorage of dental prostheses. Scand J Plast Recon Surg 1969;3:81-100

  17. 人工假体置换在股骨下段骨肉瘤合并病理性骨折保肢治疗中的应用%Application of artificial total knee prosthesis replacement in limb salvage surgery for osteosarcoma with pathological fracture located in the distal femur

    Institute of Scientific and Technical Information of China (English)

    刘燚; 崔志明; 崔胜宇; 杨健; 严建军

    2011-01-01

    BACKGROUND: Amputation surgery as a traditional treatment for osteosarcoma is preferred. With the continuous improvementof chemotherapy, prosthesis manufacturing process and materials science advances, it is possible to keep body functionsOBJECTIVE: To evaluate the effect of artificial total knee prosthesis replacement in the treatment of patients with osteosarcomaand pathological fracture located in the distal femur.METHODS: Limb salvage surgery with prosthetic knee replacement was performed in 9 patients with osteosarcoma andpathological fracture in the distal femur. The reconstruction of limb function was done using total knee replacement withindividualized prosthesis. Neoadjuvant chemotherapy was used in all the cases pre- and postoperaUvely.RESULTS AND CONCLUSION: The nine patients were followed up for 6-72 months Eight cases survived without tumor in 3years and 6 in 5 years. The 5 years survive rate was 66.7%. The range of extension and flexion of the knee was O°-1OO° in 6cases, and 3 in 0° 70°. The function of the knee was assessed by Enneking system. The results were graded as excellent in 6patients, good in 2 cases, and fair in 1 case. Material-related inflammation and rejection reactions were not found. It is effective forthe treatment of osteosarcoma and pathological fracture In the distal femur through extensive or radical resection andreconstruction by using prosthetic knee replacement.%背景:骨肉瘤的传统治疗以截肢手术为首选,随着化疗方案的不断改进,以及人工关节假体制作工艺和材料学的进步使保留肢体功能成为可能.目的:观察人工肿瘤假体在股骨下端骨肉瘤合并病理性骨折者保肢术中的临床应用效果.方法:对9例股骨下端骨肉瘤合并病理性骨折患者行肿瘤段广泛性切除或根治性切除,然后进行人工膝关节假体置换重建膝关节,置换前后均行新辅助化疗.结果与结论:9例均获得随访,随访6~72个月.无瘤3年生存者8

  18. Artificial Intelligence.

    Science.gov (United States)

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve.

  19. Plasticity in the visual system is associated with prosthesis use in phantom limb pain

    OpenAIRE

    2013-01-01

    The experience of strong phantom limb pain (PLP) in arm amputees was previously shown to be associated with structural neural plasticity in parts of the cortex that belong to dorsal and ventral visual streams. It has been speculated that this plasticity results from the extensive use of a functional prosthesis which is associated with increased visual feedback to control the artificial hand. To test this hypothesis, we reanalyzed data of cortical volumes of 21 upper limb amputees and tested t...

  20. Artificial blood.

    OpenAIRE

    1983-01-01

    #Blood substitutes have been developed for almost a century. The various type of artificial blood was continuously available on the market. The theme of this report is to identify the best substitute in emergency situation for some patients and science students. The definition of best is given; thus, as the vital part of the report, the comparison between them is described and discussed. Modified hemoglobin, bovine-based hemoglobin and PFCs are three basic types. In terms of the perfor...

  1. Artificial vision.

    Science.gov (United States)

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  2. Limb lengthening in achondroplasia

    Directory of Open Access Journals (Sweden)

    Sanjay K Chilbule

    2016-01-01

    Full Text Available Background: Stature lengthening in skeletal dysplasia is a contentious issue. Specific guidelines regarding the age and sequence of surgery, methods and extent of lengthening at each stage are not uniform around the world. Despite the need for multiple surgeries, with their attendant complications, parents demanding stature lengthening are not rare, due to the social bias and psychological effects experienced by these patients. This study describes the outcome and complications of extensive stature lengthening performed at our center. Materials and Methods: Eight achondroplasic and one hypochondroplasic patient underwent bilateral transverse lengthening for tibiae, humeri and femora. Tibia lengthening was carried out using a ring fixator and bifocal corticotomy, while a monolateral pediatric limb reconstruction system with unifocal corticotomy was used for the femur and humerus. Lengthening of each bone segment, height gain, healing index and complications were assessed. Subgroup analysis was carried out to assess the effect of age and bone segment on the healing index. Results: Nine patients aged five to 25 years (mean age 10.2 years underwent limb lengthening procedures for 18 tibiae, 10 femora and 8 humeri. Four patients underwent bilateral lengthening of all three segments. The mean length gain for the tibia, femur and humerus was 15.4 cm (100.7%, 9.9 cm (52.8% and 9.6 cm (77.9%, respectively. Healing index was 25.7, 25.6 and 20.6 days/cm, respectively, for the tibia, femur and humerus. An average of 33.3% height gain was attained. Lengthening of both tibia and femur added to projected height achieved as the 3 rd percentile of standard height in three out of four patients. In all, 33 complications were encountered (0.9 complications per segment. Healing index was not affected by age or bone segment. Conclusion: Extensive limb lengthening (more than 50% over initial length carries significant risk and should be undertaken only after due

  3. Lower limb replantations: indications and a new scoring system.

    Science.gov (United States)

    Battiston, Bruno; Tos, Pierluigi; Pontini, Italo; Ferrero, Sebastiano

    2002-01-01

    The need for reconstruction of lower limb amputations is increasing, due to high-energy trauma in road accidents and work-related injuries. The indication for lower limb replantation is still controversial. Compared with upper limb replantations, indications are more select due to the frequent complications in lower limb salvage procedures, such as severe general complications or local complications such as necrosis, infections, nonunions, the need for secondary lengthening, or other reconstructive procedures. The satisfactory results given by artificial prosthesis, such as quicker recovery time and fewer secondary procedures, also contribute to the higher degree of selection for lower limb replantation candidates. Since 1993, we have replanted 14 amputations of the lower limb in 12 patients, including 2 bilateral cases. Although survival of the replanted segment was obtained in all patients, 5 cases were subsequently amputated for severe secondary complications. Of the remaining 9 cases, evaluated by means of Chen criteria, 7 had good results (3 Chen I and 4 Chen II), 1 sufficient (Chen III), and 1 poor (Chen IV). The best results were obtained in young patients. Our experience led us to examine the necessity for careful, objective patient selection. We developed a score evaluation system by modifying the international classifying method for severe limb traumas (mangled extremity severity score, or MESS system). This relatively simple system, based on the retrospective study of our cases, considers several parameters (patient's age, general conditions, level and type of lesion, time of injury, and associated lesions), giving each one a score. The total score gives the indication for replantation, predicts the functional outcome, and facilitates decision-making.

  4. Adjustments to amputation and artificial limb, and quality of life in lower limb amputees

    NARCIS (Netherlands)

    Sinha, Richa

    2013-01-01

    Amputatie van ledematen heeft een grote impact op het individu, niet alleen bij de vervalsing van het lichaamsbeeld, maar ook van invloed op hun sociale en psychologische functioneren. Prothese is de enige manier waarop deze mensen kunnen onafhankelijk zijn, deel te nemen aan de samenleving, en herv

  5. Adjustments to amputation and artificial limb, and quality of life in lower limb amputees

    OpenAIRE

    Sinha, Richa

    2013-01-01

    Amputatie van ledematen heeft een grote impact op het individu, niet alleen bij de vervalsing van het lichaamsbeeld, maar ook van invloed op hun sociale en psychologische functioneren. Prothese is de enige manier waarop deze mensen kunnen onafhankelijk zijn, deel te nemen aan de samenleving, en hervatten hun werk. Er zijn verschillende factoren, die het gebruik van prothese door geamputeerden kan ook van invloed zijn en op hun beurt van invloed op hun kwaliteit van leven (QoL). De onderzoeksv...

  6. Limb Loss in Children: Prosthetic Issues

    Science.gov (United States)

    ... children with upper-limb (arms or hands) versus lower-limb (feet and legs) loss? Arms and legs are ... University of Illinois) studied how often children new lower-limb prostheses. His research suggests that: Children (1 to ...

  7. Evaluation of Limb-Girdle Muscular Dystrophy

    Science.gov (United States)

    2014-03-06

    Becker Muscular Dystrophy; Limb-Girdle Muscular Dystrophy, Type 2A (Calpain-3 Deficiency); Limb-Girdle Muscular Dystrophy, Type 2B (Miyoshi Myopathy, Dysferlin Deficiency); Limb-Girdle Muscular Dystrophy, Type 2I (FKRP-deficiency)

  8. 21 CFR 890.3475 - Limb orthosis.

    Science.gov (United States)

    2010-04-01

    ... PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3475 Limb orthosis. (a) Identification... improvement. Examples of limb orthoses include the following: A whole limb and joint brace, a hand splint,...

  9. Controlling pneumatic artificial muscles in exoskeletons with surface electromyography

    NARCIS (Netherlands)

    Groenhuis, Vincent; Chandrapal, Mervin; Stramigioli, Stefano; Chen, XiaoQi

    2014-01-01

    Powered exoskeletons are gaining more interest in the last few years, as useful devices to provide assistance to elderly and disabled people. Many different types of powered exoskeletons have been studied in the past. In this research paper, a soft lower limb exoskeleton driven by pneumatic artifici

  10. Positional information in axolotl and mouse limb extracellular matrix is mediated via heparan sulfate and fibroblast growth factor during limb regeneration in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Phan, Anne Q; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V; Gardiner, David M

    2015-08-01

    Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain-of-function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position-specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position-specific, developmental-stage-specific, and heparan sulfate-dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals.

  11. Simulation of Upper Limb Movements

    Science.gov (United States)

    Uherčík, Filip; Hučko, Branislav

    2011-12-01

    The paper deals with controlling an upper limb prosthesis based on the measurement of myoelectric signals (MES) while drinking. MES signals have been measured on healthy limbs to obtain the same response for the prosthesis. To simulate the drinking motion of a healthy upper limb, the program ADAMS was used, with all degrees of freedom and a hand after trans-radial amputation with an existing hand prosthesis. Modification of the simulation has the exact same logic of control, where the muscle does not have to be strenuous all the time, but it is the impulse of the muscle which drives the motor even though the impulse disappears and passed away.

  12. Prevalence and Characteristics of Phantom Limb Pain and Residual Limb Pain in the Long Term after Upper Limb Amputation

    Science.gov (United States)

    Desmond, Deirdre M.; MacLachlan, Malcolm

    2010-01-01

    This study aims to describe the prevalence and characteristics of phantom limb pain and residual limb pain after upper limb amputation. One-hundred and forty-one participants (139 males; mean age 74.8 years; mean time since amputation 50.1 years) completed a self-report questionnaire assessing residual and phantom limb pain experience. Prevalence…

  13. Artificial Economy

    Directory of Open Access Journals (Sweden)

    Alexandru JIVAN

    2011-08-01

    Full Text Available This paper proposes to eliminate, a routine in the economic thinking, claimed to be responsible for the negative essence of economic developments, from the point of view, of the ecological implications (employment in the planetary ecosystem. The methodological foundations start from the natural origins of the functionality of the human economic society according to the originary physiocrat liberalism, and from specific natural characteristics of the humankind. This paper begins with a comment-analysis of the difference between natural and artificial within the economy, and then explains some of the most serious diversions from the natural essence of economic liberalism. It shall be explained the original (heterodox interpretation of the Classical political economy (economics, by making calls to the Romanian economic thinking from aggravating past century. Highlighting the destructive impact of the economy - which, under the invoked doctrines, we call unnatural - allows an intuitive presentation of a logical extension of Marshall's market price, based on previous research. Besides the doctrinal arguments presented, the economic realities inventoried along the way (major deficiencies and effects, determined demonstrate the validity of the hypothesis of the unnatural character and therefore necessarily to be corrected, of the concept and of the mechanisms of the current economy.The results of this paper consist of original heterodox methodspresented, intuitive or developed that can be found conclusively within the key proposals for education and regulation.

  14. Endograft Limb Occlusion in EVAR

    DEFF Research Database (Denmark)

    Taudorf, M; Jensen, L P; Vogt, K C

    2014-01-01

    OBJECTIVE: To assess the incidence and outcome of graft limb occlusions after endovascular aortic repair (EVAR) of abdominal aortic aneurysm (AAA) in a high volume single centre. To quantify iliac artery tortuosity in patients with AAA and correlate this with limb occlusion. DESIGN: Data were...... collected consecutively and prospectively, and analyzed retrospectively. MATERIALS: Patients treated with Zenith bifurcated stent grafts from January 2000 to December 2010 at a tertiary referral vascular unit were analyzed. Routine regular office follow-up with computed tomography angiography (CTA) and......, subsequently, duplex ultrasound imaging was performed. Patients with limb occlusions were identified. For each index patient, two controls were obtained, one immediately preceding and one following the index patient in the consecutive cohort of EVAR patients. METHODS: Demographics and CTA data on limb graft...

  15. Percutaneous isolated limb perfusion with thrombolytics for severe limb ischemia.

    Science.gov (United States)

    Ali, Ahsan T; Kalapatapu, Venkat R; Bledsoe, Shelly; Moursi, Mohammed M; Eidt, John F

    2005-01-01

    Patients with severe tibioperoneal disease are poor candidates for a distal bypass. Absence of a distal target, lack of conduit, or multiple medical problems can make these patients a prohibitive risk for revascularization. Acute on chronic ischemia in this group poses a greater challenge. Thrombolytic therapy for acute ischemia can be prolonged and carries a significant risk of bleeding if continued beyond 24 hours. However, if the ischemic limbs can be isolated from the systemic circulation, a higher dose of the lytic agent can be given with lower risk. These are the initial results of a series of 10 patients who underwent percutaneous isolated limb perfusion with a high dose of thrombolytics for severe ischemia. Ten patients (lower extremity 8 and upper extremity 2) presented with severe limb-threatening ischemia. Mean ankle/brachial index (ABI) was 0.15 for the lower extremity, and there were no recordable digital pressures in patients with upper extremity ischemia. No distal target was visible on the initial arteriogram. These patients were then taken to the operating room, and under anesthesia, catheters were placed in an antegrade fashion via femoral approach in the popliteal artery and vein percutaneously. For upper extremity, the catheters were placed in the brachial artery and vein. A proximal tourniquet was then applied. This isolated the limb from the systemic circulation. Heparinized saline was infused through the arterial catheter while the venous catheter was left open. A closed loop or an isolated limb perfusion was confirmed when effluent became clear coming out of the venous port. A high dose of thrombolytic agent (urokinase 500,000 to 1,000,000 U) was infused into the isolated limb via the arterial catheter and drained out of the venous catheter. After 45 minutes, arterial flow was reestablished. In 4 patients, Reopro((R)) was used in addition to thrombolytics. Postprocedure angiograms showed minimal changes, but patients exhibited marked

  16. The phantom limb in dreams.

    Science.gov (United States)

    Brugger, Peter

    2008-12-01

    Mulder and colleagues [Mulder, T., Hochstenbach, J., Dijkstra, P. U., Geertzen, J. H. B. (2008). Born to adapt, but not in your dreams. Consciousness and Cognition, 17, 1266-1271.] report that a majority of amputees continue to experience a normally-limbed body during their night dreams. They interprete this observation as a failure of the body schema to adapt to the new body shape. The present note does not question this interpretation, but points to the already existing literature on the phenomenology of the phantom limb in dreams. A summary of published investigations is complemented by a note on phantom phenomena in the dreams of paraplegic patients and persons born without a limb. Integration of the available data allows the recommendation for prospective studies to consider dream content in more detail. For instance, "adaptation" to the loss of a limb can also manifest itself by seeing oneself surrounded by amputees. Such projective types of anosognosia ("transitivism") in nocturnal dreams should also be experimentally induced in normally-limbed individuals, and some relevant techniques are mentioned.

  17. Superior limb reimplantation. Case presentation.

    Directory of Open Access Journals (Sweden)

    Yovanny Ferrer Lozano

    2009-07-01

    Full Text Available Reimplantation surgery is only performed in highly specialized medical institutions. Its success is associate to the development and improvement of microsurgical techniques and to the constant training of the medical team. We present the case of a white patient of 17 years of age, who, as a result of an accident at the working place, suffered the total detachment of his upper right limb in the shoulder area. He was admitted in the emergency unit presenting hypovolemic shock and was immediately stabilized to perform later the limb reimplantation. The postsurgical development was satisfactory, proving that reimplantation can be considered a safe and functional practice in complex wounds or amputation affecting limbs.

  18. Apparatus for determining changes in limb volume

    Science.gov (United States)

    Bhagat, P. K.; Wu, V. C. (Inventor)

    1981-01-01

    Measuring apparatus for determining changes in the volume of limbs or other boty extremities by determining the cross-sectional area of such limbs many comprise a transmitter including first and second transducers for positioning on the surface of the limb at a predetermined distance there between, and a receiver including a receiver crystal for positioning on the surface of the limb. The distance between the receiver crystal and the first and second transducers are represented by respective first and second chords of the cross-section of the limb and the predetermined distance between the first and second transducers is represented by a third chord of the limb cross section.

  19. Trends in Artificial Intelligence.

    Science.gov (United States)

    Hayes, Patrick

    1978-01-01

    Discusses the foundations of artificial intelligence as a science and the types of answers that may be given to the question, "What is intelligence?" The paradigms of artificial intelligence and general systems theory are compared. (Author/VT)

  20. Artificiality in Social Sciences

    OpenAIRE

    Rennard, Jean-Philippe

    2007-01-01

    This text provides with an introduction to the modern approach of artificiality and simulation in social sciences. It presents the relationship between complexity and artificiality, before introducing the field of artificial societies which greatly benefited from the computer power fast increase, gifting social sciences with formalization and experimentation tools previously owned by "hard" sciences alone. It shows that as "a new way of doing social sciences", artificial societies should undo...

  1. Artificial life and Piaget.

    Science.gov (United States)

    Mueller, Ulrich; Grobman, K H.

    2003-04-01

    Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

  2. Focal skin defect, limb anomalies and microphthalmia.

    NARCIS (Netherlands)

    Jackson, K.E.; Andersson, H.C.

    2004-01-01

    We describe two unrelated female patients with congenital single focal skin defects, unilateral microphthalmia and limb anomalies. Growth and psychomotor development were normal and no brain malformation was detected. Although eye and limb anomalies are commonly associated, clinical anophthalmia and

  3. Congenital microgastria and hypoplastic upper limb anomalies.

    Science.gov (United States)

    Lueder, G T; Fitz-James, A; Dowton, S B

    1989-03-01

    Six cases of congenital microgastria associated with limb anomalies are reviewed. The microgastria-hypoplastic upper limb association may arise as a result of aberrant mesodermal development in the 5th embryonic week.

  4. Adolescent Neuroblastoma of Lower Limb

    Directory of Open Access Journals (Sweden)

    Rajeshwari K

    2013-04-01

    Full Text Available Neuroblastoma is an embryonic tumour of neural crest origin, commonly seen in children with upper abdomen involvement. Rarely neuroblastomas present in adolescents and adults involving lower limb. Histopathologically neuroblastoma of lower limb can be confused with other small round cell tumour especially with Ewing's sarcoma and rhabdomyosarcoma. A 16 year old male presented with 15x11cm swelling, pain and multiple discharging sinuses of right leg since 4 months. Routine haematological and biochemical analysis were within normal limits. Radiology of right leg showed large soft tissue swelling encompassing the pathological fracture of tibia and bowing of fibula. Fine needle aspiration of the swelling revealed malignant small round cell tumour. Histopathology revealed poorly differentiated neuroblastoma of lower limb. The immunohistochemistry of Synaptophysin and Chromogranin were positive and CD 99 was negative. Neuroblastoma diagnosed at unusual site with uncommon age has poor prognosis. Hence, one must keep in mind the differential diagnosis of neuroblastoma as one of the differential diagnosis in evaluating the soft tissue tumours of lower limb.

  5. Learning about Vertebrate Limb Development

    Science.gov (United States)

    Liang, Jennifer O.; Noll, Matthew; Olsen, Shayna

    2014-01-01

    We have developed an upper-level undergraduate laboratory exercise that enables students to replicate a key experiment in developmental biology. In this exercise, students have the opportunity to observe live chick embryos and stain the apical ectodermal ridge, a key tissue required for development of the vertebrate limb. Impressively, every…

  6. Homeomorphisms Between Limbs of the Mandelbrot Set

    DEFF Research Database (Denmark)

    Branner, Bodil; Fagella, Nuria

    1999-01-01

    Using a family of higher degree polynomials as a bridge, together with complex surgery techniques, we construct a homeomorphism between any two limbs of the Mandelbrot set of equal denominator. Induced by these homeomorphisms and complex conjugation, we obtain an involution between each limb...... of the limbs in the plane. As usual we plough in the dynamical planes and harvest in the parameter space....

  7. Artificial proprioceptive feedback for myoelectric control.

    Science.gov (United States)

    Pistohl, Tobias; Joshi, Deepak; Ganesh, Gowrishankar; Jackson, Andrew; Nazarpour, Kianoush

    2015-05-01

    The typical control of myoelectric interfaces, whether in laboratory settings or real-life prosthetic applications, largely relies on visual feedback because proprioceptive signals from the controlling muscles are either not available or very noisy. We conducted a set of experiments to test whether artificial proprioceptive feedback, delivered noninvasively to another limb, can improve control of a two-dimensional myoelectrically-controlled computer interface. In these experiments, participants were required to reach a target with a visual cursor that was controlled by electromyogram signals recorded from muscles of the left hand, while they were provided with an additional proprioceptive feedback on their right arm by moving it with a robotic manipulandum. Provision of additional artificial proprioceptive feedback improved the angular accuracy of their movements when compared to using visual feedback alone but did not increase the overall accuracy quantified with the average distance between the cursor and the target. The advantages conferred by proprioception were present only when the proprioceptive feedback had similar orientation to the visual feedback in the task space and not when it was mirrored, demonstrating the importance of congruency in feedback modalities for multi-sensory integration. Our results reveal the ability of the human motor system to learn new inter-limb sensory-motor associations; the motor system can utilize task-related sensory feedback, even when it is available on a limb distinct from the one being actuated. In addition, the proposed task structure provides a flexible test paradigm by which the effectiveness of various sensory feedback and multi-sensory integration for myoelectric prosthesis control can be evaluated.

  8. Retrieval of tropospheric column densities of NO2 from combined SCIAMACHY nadir/limb measurements

    Directory of Open Access Journals (Sweden)

    T. Wagner

    2009-11-01

    Full Text Available The SCIAMACHY instrument onboard the ESA satellite ENVISAT allows the retrieval of column densities of various trace gases, among them NO2. As only instrument of its kind, SCIAMACHY measures in an alternating limb/nadir mode. The limb measurements allow a direct determination of stratospheric column densities, which are needed to extract tropospheric from the total column density measurements performed in (quasi simultaneous nadir geometry. Here we discuss the potential and limitations of SCIAMACHY limb measurements for estimating stratospheric column densities of NO2 in comparison to a simple reference sector method, and the consequences for the resulting tropospheric column densities. A direct, absolute limb correction scheme improves spatial patterns of tropospheric NO2 column densities at high latitudes compared to the simple reference sector method. However, it results in artificial zonal stripes at low latitudes. Thus, also a relative limb correction scheme was defined, which turned out to successfully reduce stratospheric artefacts in the resulting tropospheric data product without introducing new ones. This relative limb correction scheme is rather simple, robust, and, in essence, based on measurements alone. The effect of the different stratospheric estimation schemes on tropospheric column densities is discussed with respect to zonal and temporal dependencies. In addition, error quantities are defined from the nadir/limb measurements which indicate remaining systematic errors as function of latitude and day. Our new suggested stratospheric estimation scheme, the relative limb correction, improves monthly mean tropospheric slant column densities significantly, e.g. from −1×1015 molec/cm2 (using a simple reference sector method to ≈0 in the Atlantic ocean, and from +1×1015 molec/cm2 to ≈0 over Siberia, at 50° N in January.

  9. Gremlin1 induces anterior-posterior limb bifurcations in developing Xenopus limbs but does not enhance limb regeneration.

    Science.gov (United States)

    Wang, Yi-Hsuan; Keenan, Samuel R; Lynn, Jeremy; McEwan, James C; Beck, Caroline W

    2015-11-01

    Gremlin1 (grem1) has been previously identified as being significantly up-regulated during regeneration of Xenopus laevis limbs. Grem1 is an antagonist of bone morphogenetic proteins (BMPs) with a known role in limb development in amniotes. It forms part of a self-regulating feedback loop linking epithelial (FGF) and mesenchymal (shh) signalling centres, thereby controlling outgrowth, anterior posterior and proximal distal patterning. Spatiotemporal regulation of the same genes in developing and regenerating Xenopus limb buds supports conservation of this mechanism. Using a heat shock inducible grem1 (G) transgene to created temperature regulated stable lines, we have shown that despite being upregulated in regeneration, grem1 overexpression does not enhance regeneration of tadpole hindlimbs. However, both the regenerating and contralateral, developing limb of G transgenics developed skeletal defects, suggesting that overexpressing grem1 negatively affects limb patterning. When grem1 expression was targeted earlier in limb bud development, we saw dramatic bifurcations of the limbs resulting in duplication of anterior posterior (AP) pattern, forming a phenotypic continuum ranging from duplications arising at the level of the femoral head to digit bifurcations, but never involving the pelvis. Intriguingly, the original limbs have AP pattern inversion due to de-restricted Shh signalling. We discuss a possible role for Grem1 regulation of limb BMPs in regulation of branching pattern in the limbs.

  10. Artificial cognition architectures

    CERN Document Server

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  11. Ultrasound imaging in lower limb prosthetics.

    Science.gov (United States)

    Douglas, Tania; Solomonidis, Stephan; Sandham, William; Spence, William

    2002-03-01

    The biomechanical interaction between the residual limb and the prosthetic socket determines the quality of fit of the socket in lower limb prosthetics. An understanding of this interaction and the development of quantitative measures to predict the quality of fit of the socket are important for optimal socket design. Finite-element modeling is used widely for biomechanical modeling of the limb/socket interaction and requires information on the internal and external geometry of the residual limb. Volumetric imaging methods such as X-ray computed tomography, magnetic resonance imaging, and ultrasound have been used to obtain residual limb shape information. Of these modalities, ultrasound has been introduced most recently and its development for visualization in prosthetics is the least mature. This paper reviews ultrasound image acquisition and processing methods as they have been applied in lower limb prosthetics.

  12. Artificial life and life artificialization in Tron

    Directory of Open Access Journals (Sweden)

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  13. Customizable Rehabilitation Lower Limb Exoskeleton System

    OpenAIRE

    Riaan Stopforth

    2012-01-01

    Disabled people require assistance with the motion of their lower limbs to improve rehabilitation. Exoskeletons used for lower limb rehabilitation are highly priced and are not affordable to the lowerincome sector of the population. This paper describes an exoskeleton lower limb system that was designed keeping in mind that the cost must be as low as possible. The forward kinematic system that is used must be a simplified model to decrease computational time, yet allow the exoskeleton to be a...

  14. New concepts in lower limb orthotics.

    Science.gov (United States)

    Loke, M

    2000-08-01

    Lower limb orthotics is in the process of a default transformation because of its association with lower limb prosthetics, a mechanical discipline that has translated component and material innovations into balance and velocity function gains to achieve a level of ambulation not possible a generation ago. This article discusses the fundamental mechanical similarities and differences of lower limb orthotics to prosthetics and their application to orthoses designed to improve the gait outcome of patients requiring orthotic intervention.

  15. Onion artificial muscles

    Science.gov (United States)

    Chen, Chien-Chun; Shih, Wen-Pin; Chang, Pei-Zen; Lai, Hsi-Mei; Chang, Shing-Yun; Huang, Pin-Chun; Jeng, Huai-An

    2015-05-01

    Artificial muscles are soft actuators with the capability of either bending or contraction/elongation subjected to external stimulation. However, there are currently no artificial muscles that can accomplish these actions simultaneously. We found that the single layered, latticed microstructure of onion epidermal cells after acid treatment became elastic and could simultaneously stretch and bend when an electric field was applied. By modulating the magnitude of the voltage, the artificial muscle made of onion epidermal cells would deflect in opposing directions while either contracting or elongating. At voltages of 0-50 V, the artificial muscle elongated and had a maximum deflection of -30 μm; at voltages of 50-1000 V, the artificial muscle contracted and deflected 1.0 mm. The maximum force response is 20 μN at 1000 V.

  16. Finite element analysis of a composite artificial ankle

    Science.gov (United States)

    Perkins, Leigh Ann; Johnston, Lawrence; Denniston, Charles; Czekalski, Blaise E.

    1993-01-01

    Ultra-light carbon fiber composite materials are being utilized in artificial limbs with increasing frequency in recent years. Dr. Arthur Copes, an orthotist from Baton Rouge, Louisiana, has developed a graphite expoxy composite material artificial ankle (Copes/Bionic Ankle) that is intended to be used by amputees who require the most advanced above-and-below-the-knee prosthetic devices. The Copes/Bionic Ankle is designed to reproduce the function of the natural ankle joint by allowing the composite material to act as a spring mechanism without the use of metal mechanical parts. NASA Marshall Space Flight Center has agreed to participate in the design effort by providing the structural analysis of the artificial ankle design.

  17. Selection and control of limb posture for stability

    NARCIS (Netherlands)

    Franklin, D.W.; Selen, L.P.J.; Franklin, S.; Wolpert, D.M.

    2013-01-01

    Impedance control can be used to stabilize the limb against both instability and unpredictable perturbations. Limb posture influences motor noise, energy usage and limb impedance as well as their interaction. Here we examine whether subjects use limb posture as part of a mechanism to regulate limb s

  18. [Critical limb ischemia--update].

    Science.gov (United States)

    Melamed, Eitan; Kotyba, Baydousi; Galili, Offer; Karmeli, Ron

    2010-12-01

    Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery occlusive disease. Without timely diagnosis and revascularization, patients with CLI are at risk of devastating complications including loss of limb and life. Therapeutic goals in treating patients with CLI include reducing cardiovascular risk factors, relieving ischemic pain, heating ulcers, preventing major amputation, improving quality of life and increasing survival. These aims may be achieved through medical therapy, revascularization or amputation. The past decade has seen substantial growth in endovascular therapies and options now exist for treating long segment occlusive disease, but surgical bypass may still yield more durable results. Patients who are younger, more active, and at low risk for surgery, may have better outcomes undergoing an operation. This is also indicated for endovascular failures, which may include technical failures or late occlusions after stents or other procedures. In contrast, frail patients with a limited life expectancy may experience better outcomes with endovascular therapy. For patients who are non-ambulatory, demented, or unfit to undergo revascularization, an amputation should be considered.

  19. Rehabilitation of lower limb amputees

    OpenAIRE

    Kovač, Ida; KAUZLARIĆ, NEVEN; Živković, Ognjen; Mužić, Vedrana; ABRAMOVIĆ, Marina; VULETIĆ, Zoran; Vukić, Tamara; IŠTVANOVIĆ, Neven; LIVAKOVIĆ, BRANKO

    2015-01-01

    Rehabilitation of amputees represents a complex process during the course of which an amputee receives professional aid and support, so as to adapt to the use of prosthesis, i.e. an artificial supplement for the lost body part. The process aims at achieving an independent performance of the amputee in all areas of everyday life and as high quality of life as possible. The rehabilitation encompasses not only the pre-amputation, postoperative, pre-prosthetic and prosthetic stage, within which a...

  20. Artificial intelligence in medicine.

    Science.gov (United States)

    Ramesh, A. N.; Kambhampati, C.; Monson, J. R. T.; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. RESULTS: The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. DISCUSSION: Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting. PMID:15333167

  1. The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb

    Science.gov (United States)

    Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A.

    2016-01-01

    Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation. PMID:27583121

  2. The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb.

    Science.gov (United States)

    Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A; Danish, Qazi

    2016-09-01

    Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation.

  3. Sports participation of Dutch lower limb amputees

    NARCIS (Netherlands)

    Bragaru, Mihail; Meulenbelt, Hendrik; Dijkstra, Pieter U.; Geertzen, Jan H.B.; Dekker, Rienk

    2013-01-01

    Objective: To analyze sports participation of Dutch lower limb amputees and factors influencing sports participation. Study design: A cross-sectional survey was performed. Dutch lower limb amputees (N = 2039) were invited to participate in a postal survey addressing personal and amputation character

  4. Recipient twin limb ischemia with postnatal onset.

    Science.gov (United States)

    Broadbent, Roland Spencer

    2007-02-01

    After the occurrence of 3 local cases of limb ischemia in newborn twins, we reviewed the literature to investigate this combination systematically. This review reveals a distinct condition: postnatal onset limb ischemia affecting recipient twins in twin-twin transfusion syndrome.

  5. Update on embryology of the upper limb.

    Science.gov (United States)

    Al-Qattan, Mohammad M; Kozin, Scott H

    2013-09-01

    Current concepts in the steps of upper limb development and the way the limb is patterned along its 3 spatial axes are reviewed. Finally, the embryogenesis of various congenital hand anomalies is delineated with an emphasis on the pathogenetic basis for each anomaly.

  6. Interhemispheric sensorimotor integration; an upper limb phenomenon?

    Science.gov (United States)

    Ruddy, Kathy L; Jaspers, Ellen; Keller, Martin; Wenderoth, Nicole

    2016-10-01

    Somatosensory information from the limbs reaches the contralateral Primary Sensory Cortex (S1) with a delay of 23ms for finger, and 40ms for leg (somatosensory N20/N40). Upon arrival of this input in the cortex, motor evoked potentials (MEPs) elicited by Transcranial Magnetic Stimulation (TMS) are momentarily inhibited. This phenomenon is called 'short latency afferent inhibition (SAI)' and can be used as a tool for investigating sensorimotor interactions in the brain. We used SAI to investigate the process of sensorimotor integration in the hemisphere ipsilateral to the stimulated limb. We hypothesized that ipsilateral SAI would occur with a delay following the onset of contralateral SAI, to allow for transcallosal conduction of the signal. We electrically stimulated the limb either contralateral or ipsilateral to the hemisphere receiving TMS, using a range of different interstimulus intervals (ISI). We tested the First Dorsal Interosseous (FDI) muscle in the hand, and Tibialis Anterior (TA) in the lower leg, in three separate experiments. Ipsilateral SAI was elicited in the upper limb (FDI) at all ISIs that were greater than N20+18ms (all p<.05) but never at any earlier timepoint. No ipsilateral SAI was detected in the lower limb (TA) at any of the tested ISIs. The delayed onset timing of ipsilateral SAI suggests that transcallosal communication mediates this inhibitory process for the upper limb. The complete absence of ipsilateral SAI in the lower limb warrants consideration of the potential limb-specific differences in demands for bilateral sensorimotor integration.

  7. Claimed walking distance of lower limb amputees

    NARCIS (Netherlands)

    Geertzen, JHB; Bosmans, JC; Van der Schans, CP; Dijkstra, PU

    2005-01-01

    Purpose: Walking ability in general and specifically for lower limb amputees is of major importance for social mobility and ADL independence. Walking determines prosthesis prescription. The aim of this study was to mathematically analyse factors influencing claimed walking distance of lower limb amp

  8. Four cases of trisomy 18 syndrome with limb reduction malformations.

    OpenAIRE

    Christianson, A L; Nelson, M. M.

    1984-01-01

    Limb reduction malformations of the arms are well documented in the trisomy 18 syndrome. Four cases of trisomy 18 syndrome with limb reduction malformations of the legs are described and compared with the upper limb malformations.

  9. The aneurogenic limb identifies developmental cell interactions underlying vertebrate limb regeneration.

    Science.gov (United States)

    Kumar, Anoop; Delgado, Jean-Paul; Gates, Phillip B; Neville, Graham; Forge, Andrew; Brockes, Jeremy P

    2011-08-16

    The removal of the neural tube in salamander embryos allows the development of nerve-free aneurogenic limbs. Limb regeneration is normally nerve-dependent, but the aneurogenic limb regenerates without nerves and becomes nerve-dependent after innervation. The molecular basis for these tissue interactions is unclear. Anterior Gradient (AG) protein, previously shown to rescue regeneration of denervated limbs and to act as a growth factor for cultured limb blastemal cells, is expressed throughout the larval limb epidermis and is down-regulated by innervation. In an aneurogenic limb, the level of AG protein remains high in the epidermis throughout development and regeneration, but decreases after innervation following transplantation to a normal host. Aneurogenic epidermis also shows a fivefold difference in secretory gland cells, which express AG protein. The persistently high expression of AG in the epithelial cells of an aneurogenic limb ensures that regeneration is independent of the nerve. These findings provide an explanation for this classical problem, and identify regulation of the epidermal niche by innervation as a distinctive developmental mechanism that initiates the nerve dependence of limb regeneration. The absence of this regulation during anuran limb development might suggest that it evolved in relation to limb regeneration.

  10. Cross-limb Interference during motor learning

    DEFF Research Database (Denmark)

    Lauber, Benedikt; Jensen, Jesper Lundbye; Keller, Martin;

    2013-01-01

    the training, after the training and in an immediate retention test after the practice of the interference task for both the trained and the untrained hand. After training, subjects showed not only significant learning and interference effects for the trained limb but also for the contralateral untrained limb......It is well known that following skill learning, improvements in motor performance may transfer to the untrained contralateral limb. It is also well known that retention of a newly learned task A can be degraded when learning a competing task B that takes place directly after learning A. Here we...... investigate if this interference effect can also be observed in the limb contralateral to the trained one. Therefore, five different groups practiced a ballistic finger flexion task followed by an interfering visuomotor accuracy task with the same limb. Performance in the ballistic task was tested before...

  11. On stellar limb darkening and exoplanetary transits

    CERN Document Server

    Howarth, Ian D

    2011-01-01

    This paper examines how to compare stellar limb-darkening coefficients evaluated from model atmospheres with those estimated from photometry. Limb-darkening coefficients derived from light-curve analyses using approximate limb-darkening `laws' are shown to be dependent on system geometry, while different characterizations of a given model atmosphere can give quite different numerical results. These issues are examined in the context of exoplanetary transits, which offer significant advantages over traditional binary-star eclipsing systems in the investigation of stellar limb darkening. `Like for like' comparisons between light-curve analyses and new model-atmosphere results, mediated by synthetic photometry, are conducted for a small sample of stars. Agreement between the resulting synthetic-photometry/atmosphere-model (SPAM) limb-darkening coefficients and empirical values ranges from very good to quite poor, even though there is only a small dispersion in fundamental stellar parameters.

  12. NECROTIZING FASCIITIS OF LIMB: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Dhaarna

    2015-11-01

    Full Text Available Necrotizing fasciitis is a severe, rare, potentially lethal, soft tissue infection that tends to develop in scrotum, perineum, abdominal wall or the extremities. It is a medical emergency that threatens both patient’s limb and life. Necrotizing fasciitis has the potential to become quite severe - in such cases a radical debridement amounting to amputation of the limb may be required to save the patient’s life. Early diagnosis requires a high index of suspicion. We describe a case of a 49-year-old obese woman who developed necrotizing fasciitis in her left lower limb for which she underwent multiple radical surgical debridement, followed by skin grafting for reconstruction of the limb defects. Our main focus was to salvage the limb with the help of antibiotics and multiple debridements. This report emphasizes the need to have a relook at the use of Parenteral Crystalline Penicillin and diligent management of wounds resulting from repeated debridements.

  13. Slow Movements of Bio-Inspired Limbs

    Science.gov (United States)

    Babikian, Sarine; Valero-Cuevas, Francisco J.; Kanso, Eva

    2016-10-01

    Slow and accurate finger and limb movements are essential to daily activities, but the underlying mechanics is relatively unexplored. Here, we develop a mathematical framework to examine slow movements of tendon-driven limbs that are produced by modulating the tendons' stiffness parameters. Slow limb movements are driftless in the sense that movement stops when actuations stop. We demonstrate, in the context of a planar tendon-driven system representing a finger, that the control of stiffness suffices to produce stable and accurate limb postures and quasi-static (slow) transitions among them. We prove, however, that stable postures are achievable only when tendons are pretensioned, i.e., they cannot become slack. Our results further indicate that a non-smoothness in slow movements arises because the precision with which individual stiffnesses need to be altered changes substantially throughout the limb's motion.

  14. [Psychological adjustment following lower limb amputation].

    Science.gov (United States)

    Panyi, Lilla Krisztina; Lábadi, Beatrix

    2015-09-27

    Rehabilitation of lower limb amputees and the fitting of their prosthesis depend highly on the psychological adjustment process and motivational state of the patient. The loss of a limb is extremely challenging and can cause various physical and psychological problems. Depression, anxiety, decreased well-being and quality of life, body image dissatisfaction and changes in self-concept and identity are frequent after lower limb amputation. In the interest of adjustment patients have to cope with the emerging changes and difficulties in their lifes as well as the problems in psychological functioning. It is important for them to accept the alterations in their body and identity, and integrate them in a new self-concept in which process motivation is a fundamental issue. The aim of this article is to review the literature on psychological consequences of lower limb amputation, and to propose an integrative way of rehabilitation for lower limb amputees.

  15. Saunders's framework for understanding limb development as a platform for investigating limb evolution.

    Science.gov (United States)

    Young, John J; Tabin, Clifford J

    2016-11-11

    John W. Saunders, Jr. made seminal discoveries unveiling how chick embryos develop their limbs. He discovered the apical ectodermal ridge (AER), the zone of polarizing activity (ZPA), and the domains of interdigital cell death within the developing limb and determined their function through experimental analysis. These discoveries provided the basis for subsequent molecular understanding of how vertebrate limbs are induced, patterned, and differentiated. These mechanisms are strongly conserved among the vast diversity of tetrapod limbs suggesting that relatively minor changes and tweaks to the molecular cascades are responsible for the diversity observed in nature. Analysis of the pathway systems first identified by Saunders in the context of animals displaying limb reduction show how alterations in these pathways have resulted in multiple mechanisms of limb and digit loss. Other classes of modification to these same patterning systems are seen at the root of other, novel limb morphological alterations and elaborations.

  16. Threatened limb from stingray injury.

    Science.gov (United States)

    Shiraev, Timothy P; Marucci, Damian; McMullin, Gabrielle

    2016-01-01

    We present the case of a 43-year-old female who suffered a stingray injury to her left ankle. The sting caused occlusion of the dorsalis pedis artery, causing dry gangrene of the medial forefoot. A below knee amputation was recommended but she was transferred for a second opinion. A Prostaglandin E1 infusion was commenced, resulting in alleviation of pain and improvement in perfusion. Amputation of great and second toes was performed, with the head of the first metatarsal preserved and covered via a cross-over skin flap raised from the contralateral leg. Achilles tendon lengthening was then performed to return the foot to a functional position. This case serves to highlight the utility of prostaglandin infusion, and the requirement for a multidisciplinary approach to critical limb ischemia in order to avoid major amputation.

  17. Sonic Hedgehog Signaling in Limb Development

    Science.gov (United States)

    Tickle, Cheryll; Towers, Matthew

    2017-01-01

    The gene encoding the secreted protein Sonic hedgehog (Shh) is expressed in the polarizing region (or zone of polarizing activity), a small group of mesenchyme cells at the posterior margin of the vertebrate limb bud. Detailed analyses have revealed that Shh has the properties of the long sought after polarizing region morphogen that specifies positional values across the antero-posterior axis (e.g., thumb to little finger axis) of the limb. Shh has also been shown to control the width of the limb bud by stimulating mesenchyme cell proliferation and by regulating the antero-posterior length of the apical ectodermal ridge, the signaling region required for limb bud outgrowth and the laying down of structures along the proximo-distal axis (e.g., shoulder to digits axis) of the limb. It has been shown that Shh signaling can specify antero-posterior positional values in limb buds in both a concentration- (paracrine) and time-dependent (autocrine) fashion. Currently there are several models for how Shh specifies positional values over time in the limb buds of chick and mouse embryos and how this is integrated with growth. Extensive work has elucidated downstream transcriptional targets of Shh signaling. Nevertheless, it remains unclear how antero-posterior positional values are encoded and then interpreted to give the particular structure appropriate to that position, for example, the type of digit. A distant cis-regulatory enhancer controls limb-bud-specific expression of Shh and the discovery of increasing numbers of interacting transcription factors indicate complex spatiotemporal regulation. Altered Shh signaling is implicated in clinical conditions with congenital limb defects and in the evolution of the morphological diversity of vertebrate limbs. PMID:28293554

  18. Artificial Neural Networks

    OpenAIRE

    Chung-Ming Kuan

    2006-01-01

    Artificial neural networks (ANNs) constitute a class of flexible nonlinear models designed to mimic biological neural systems. In this entry, we introduce ANN using familiar econometric terminology and provide an overview of ANN modeling approach and its implementation methods.

  19. Introduction to artificial intelligence

    Science.gov (United States)

    Cheeseman, P.; Gevarter, W.

    1986-01-01

    This paper presents an introductory view of Artificial Intelligence (AI). In addition to defining AI, it discusses the foundations on which it rests, research in the field, and current and potential applications.

  20. Principles of artificial intelligence

    CERN Document Server

    Nilsson, Nils J

    1980-01-01

    A classic introduction to artificial intelligence intended to bridge the gap between theory and practice, Principles of Artificial Intelligence describes fundamental AI ideas that underlie applications such as natural language processing, automatic programming, robotics, machine vision, automatic theorem proving, and intelligent data retrieval. Rather than focusing on the subject matter of the applications, the book is organized around general computational concepts involving the kinds of data structures used, the types of operations performed on the data structures, and the properties of th

  1. Physics of Artificial Gravity

    Science.gov (United States)

    Bukley, Angie; Paloski, William; Clement, Gilles

    2006-01-01

    This chapter discusses potential technologies for achieving artificial gravity in a space vehicle. We begin with a series of definitions and a general description of the rotational dynamics behind the forces ultimately exerted on the human body during centrifugation, such as gravity level, gravity gradient, and Coriolis force. Human factors considerations and comfort limits associated with a rotating environment are then discussed. Finally, engineering options for designing space vehicles with artificial gravity are presented.

  2. Heidegger and artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, G.

    1987-01-01

    The discipline of Artificial Intelligence, in its quest for machine intelligence, showed great promise as long as its areas of application were limited to problems of a scientific and situation neutral nature. The attempts to move beyond these problems to a full simulation of man's intelligence has faltered and slowed it progress, largely because of the inability of Artificial Intelligence to deal with human characteristic, such as feelings, goals, and desires. This dissertation takes the position that an impasse has resulted because Artificial Intelligence has never been properly defined as a science: its objects and methods have never been identified. The following study undertakes to provide such a definition, i.e., the required ground for Artificial Intelligence. The procedure and methods employed in this study are based on Heidegger's philosophy and techniques of analysis as developed in Being and Time. Results of this study show that both the discipline of Artificial Intelligence and the concerns of Heidegger in Being and Time have the same object; fundamental ontology. The application of Heidegger's conclusions concerning fundamental ontology unites the various aspects of Artificial Intelligence and provides the articulation which shows the parts of this discipline and how they are related.

  3. The mangled limb: salvage versus amputation.

    Science.gov (United States)

    Wolinsky, Philip R; Webb, Lawrence X; Harvey, Edward J; Tejwani, Nirmal C

    2011-01-01

    A mangled extremity is defined as a limb with injury to three of four systems in the extremity. The decision to salvage or amputate the injured limb has generated much controversy in the literature, with studies to support advantages of each approach. Various scoring systems have proved unreliable in predicting the need for amputation or salvage; however, a recurring theme in the literature is that the key to limb viability seems to be the severity of the soft-tissue injury. Factors such as associated injuries, patient age, and comorbidities (such as diabetes) also should be considered. Attempted limb salvage should be considered only if a patient is hemodynamically stable enough to tolerate the necessary surgical procedures and blood loss associated with limb salvage. For persistently hemodynamically unstable patients and those in extremis, life comes before limb. Recently, the Lower Extremity Assessment Project study attempted to answer the question of whether amputation or limb salvage achieves a better outcome. The study also evaluated other factors, including return-to-work status, impact of the level of and bilaterality of the amputation, and economic cost. There appears to be no significant difference in return to work, functional outcomes, or the cost of treatment (including the prosthesis) between the two groups. A team approach with different specialties, including orthopaedics, plastic surgery, vascular surgery and trauma general surgery, is recommended for treating patients with a mangled extremity.

  4. Cross-limb interference during motor learning.

    Directory of Open Access Journals (Sweden)

    Benedikt Lauber

    Full Text Available It is well known that following skill learning, improvements in motor performance may transfer to the untrained contralateral limb. It is also well known that retention of a newly learned task A can be degraded when learning a competing task B that takes place directly after learning A. Here we investigate if this interference effect can also be observed in the limb contralateral to the trained one. Therefore, five different groups practiced a ballistic finger flexion task followed by an interfering visuomotor accuracy task with the same limb. Performance in the ballistic task was tested before the training, after the training and in an immediate retention test after the practice of the interference task for both the trained and the untrained hand. After training, subjects showed not only significant learning and interference effects for the trained limb but also for the contralateral untrained limb. Importantly, the interference effect in the untrained limb was dependent on the level of skill acquisition in the interfering motor task. These behavioural results of the untrained limb were accompanied by training specific changes in corticospinal excitability, which increased for the hemisphere ipsilateral to the trained hand following ballistic training and decreased during accuracy training of the ipsilateral hand. The results demonstrate that contralateral interference effects may occur, and that interference depends on the level of skill acquisition in the interfering motor task. This finding might be particularly relevant for rehabilitation.

  5. The functional anatomy of suggested limb paralysis.

    Science.gov (United States)

    Deeley, Quinton; Oakley, David A; Toone, Brian; Bell, Vaughan; Walsh, Eamonn; Marquand, Andre F; Giampietro, Vincent; Brammer, Michael J; Williams, Steven C R; Mehta, Mitul A; Halligan, Peter W

    2013-02-01

    Suggestions of limb paralysis in highly hypnotically suggestible subjects have been employed to successfully model conversion disorders, revealing similar patterns of brain activation associated with attempted movement of the affected limb. However, previous studies differ with regard to the executive regions involved during involuntary inhibition of the affected limb. This difference may have arisen as previous studies did not control for differences in hypnosis depth between conditions and/or include subjective measures to explore the experience of suggested paralysis. In the current study we employed functional magnetic resonance imaging (fMRI) to examine the functional anatomy of left and right upper limb movements in eight healthy subjects selected for high hypnotic suggestibility during (i) hypnosis (NORMAL) and (ii) attempted movement following additional left upper limb paralysis suggestions (PARALYSIS). Contrast of left upper limb motor function during NORMAL relative to PARALYSIS conditions revealed greater activation of contralateral M1/S1 and ipsilateral cerebellum, consistent with the engagement of these regions in the completion of movements. By contrast, two significant observations were noted in PARALYSIS relative to NORMAL conditions. In conjunction with reports of attempts to move the paralysed limb, greater supplementary motor area (SMA) activation was observed, a finding consistent with the role of SMA in motor intention and planning. The anterior cingulate cortex (ACC, BA 24) was also significantly more active in PARALYSIS relative to NORMAL conditions - suggesting that ACC (BA 24) may be implicated in involuntary, as well as voluntary inhibition of prepotent motor responses.

  6. Smartphone supported upper limb prosthesis

    Directory of Open Access Journals (Sweden)

    Hepp D.

    2015-09-01

    Full Text Available State of the art upper limb prostheses offer up to six active DoFs (degrees of freedom and are controlled using different grip patterns. This low number of DoFs combined with a machine-human-interface which does not provide control over all DoFs separately result in a lack of usability for the patient. The aim of this novel upper limb prosthesis is both offering simplified control possibilities for changing grip patterns depending on the patients’ priorities and the improvement of grasp capability. Design development followed the design process requirements given by the European Medical Device Directive 93/42 ECC and was structured into the topics mechanics, software and drive technology. First user needs were identified by literature research and by patient feedback. Consequently, concepts were evaluated against technical and usability requirements. A first evaluation prototype with one active DoF per finger was manufactured. In a second step a test setup with two active DoF per finger was designed. The prototype is connected to an Android based smartphone application. Two main grip patterns can be preselected in the software application and afterwards changed and used by the EMG signal. Three different control algorithms can be selected: “all-day”, “fine” and “tired muscle”. Further parameters can be adjusted to customize the prosthesis to the patients’ needs. First patient feedback certified the prosthesis an improved level of handling compared to the existing devices. Using the two DoF test setup, the possibilities of finger control with a neural network are evaluated at the moment. In a first user feedback test, the smartphone based software application increased the device usability, e.g. the change within preselected grip patterns and the “tired muscle” algorithm. Although the overall software application was positively rated, the handling of the prosthesis itself needs to be proven within a patient study to be

  7. 髋臼肿瘤的保肢治疗%Limb-salvage surgery for acetabular tumors

    Institute of Scientific and Technical Information of China (English)

    徐万鹏

    2013-01-01

    Surgical treatment of acetabular tumors referred to extensive amputation or limb salvage therapy for the treatments of acetabulum and its surrounding bone destruction caused by primary malignant bone tumors or aggressive benign bone tumors. The surgical treatment of malignant tumors before 1991 was mainly half pelvic amputation. From March 1991 to April 2003, local resection and re-implantation using allograft pelvis or inactivated tumor bone shell reconstruction were performed. Limb salvage was achieved. Half of the patients were cured with weight-bearing walking with a cane or crutches. The authors have been using their own designed artificial pelvic prosthesis for reconstruction after 2003. They pointed out that mounting should be on pressure transforming line. The prosthesis and the host bone were fixed without loosening during the follow-up. The majority of patients have good hip function as the contralateral hip. Patients’ gait may be limp, but could be able to walk independently. With the diagnosis and treatment practice for years, pelvic tumors were not so uncommon and the treatment was challenging. The pathology of acetabular tumor was complex and diverse, and it was tumors nearing multiple organs that made it difficult to diagnose early and misdiagnosis and wrong treatment occurred. In accordance with the nature of the tumor, tumor size, amputation or limb salvage could be used. It was difficult to resect tumors and limb salvage was a type of rescue methods. Fully preoperative preparation and postoperative care should be emphasized. The disease could be cured with assistant chemotherapy and radiotherapy.

  8. Transducers for ultrasonic limb plethysmography

    Science.gov (United States)

    Nickell, W. T.; Wu, V. C.; Bhagat, P. K.

    1983-01-01

    The design, construction, and performance characteristics of ultasonic transducers suitable for limb plethysmography are presented. Both 3-mm-diameter flat-plate and 12-mm-diameter hemispheric ceramic transducers operating at 2 MHz were fitted in 1-mm thick epoxy-resin lens/acoustic-coupling structures and mounted in exercie-EKG electrode housings for placement on the calf using adhesive collars. The effects of transducer directional characteristics on performance under off-axis rotation and the electrical impedances of the transducers were measured: The flat transducer was found to be sensitive to rotation and have an impedance of 800 ohms; the hemispheric transducer, to be unaffected by rotation and have an impedance of 80 ohms. The use of hemispheric transducers as both transmitter and receiver, or of a flat transducer as transmitter and a hemispheric transducer as receiver, was found to produce adequate dimensional measurements, with minimum care in transducer placement, in short-term physiological experiments and long-term (up to 7-day) attachment tests.

  9. Schwannoma in the Upper Limbs

    Directory of Open Access Journals (Sweden)

    Chris Yuk Kwan Tang

    2013-01-01

    Full Text Available Schwannomas are the commonest tumours of peripheral nerves. Despite the classical description that schwannomas are well encapsulated and can be completely enucleated during excision, a portion of them have fascicular involvement and could not be completely shelled out. A retrospective review for 8 patients was carried out over 10 years. 75% of schwannoma occurred over the distal region of upper limb (at elbow or distal to it. It occurs more in the mixed nerve instead of pure sensory or motor nerve. 50% of patients had mixed nerve involvement. Fascicular involvement was very common in schwannoma (75% of patients. Removal of the tumour with fascicles can cause functional deficit. At present, there is no method (including preoperative MRI which can predict the occurrence of fascicular involvement; the authors therefore proposed a new system to stratify patients who may benefit from interfascicular nerve grafts. In this group of patients, the authors strongly recommend that the possibility and option of nerve graft should be discussed with patients prior to schwannoma excision, so that nerve grafting could be directly proceeded with patient consent in case there is fascicular involvement of tumour found intraoperatively.

  10. Development of limb volume measuring system

    Science.gov (United States)

    Bhagat, P. K.; Kadaba, P. K.

    1983-01-01

    The mechanisms underlying the reductions in orthostatic tolerance associated with weightlessness are not well established. Contradictory results from measurements of leg volume changes suggest that altered venomotor tone and reduced blood flow may not be the only contributors to orthostatic intolerance. It is felt that a more accurate limb volume system which is insensitive to environmental factors will aid in better quantification of the hemodynamics of the leg. Of the varous limb volume techniques presently available, the ultrasonic limb volume system has proven to be the best choice. The system as described herein is free from environmental effects, safe, simple to operate and causes negligible radio frequency interference problems. The segmental ultrasonic ultrasonic plethysmograph is expected to provide a better measurement of limb volume change since it is based on cross-sectional area measurements.

  11. Gait initiation in lower limb amputees

    NARCIS (Netherlands)

    Vrieling, A.H.; van Keeken, H.G.; Schoppen, T.; Otten, E.; Halbertsma, J.P.; Hof, A.L.; Postema, K.

    2008-01-01

    Objective: To study limitations in function and adjustment strategies in lower limb amputees during gait initiation. Design: Observational cohort study. Setting: University Medical Center. Participants: Amputees with a unilateral transfemoral or transtibial amputation, and able-bodied subjects. Main

  12. Obstacle crossing in lower limb amputees

    NARCIS (Netherlands)

    Vrieling, A.H.; van Keeken, H.G.; Schoppen, Tanneke; Otten, Egbert; Halbertsma, J.P.; Hof, A.L.; Postema, K.

    2007-01-01

    Objective: To study limitations in function and adjustment strategies in lower limb amputees during obstacle crossing. Design: Observational cohort study. Subjects: Transfemoral and transtibial amputees and able-bodied control subjects. Methods: In a motion analysis laboratory unimpeded and obstacle

  13. Skeletal muscle dedifferentiation during salamander limb regeneration.

    Science.gov (United States)

    Wang, Heng; Simon, András

    2016-10-01

    Salamanders can regenerate entire limbs throughout their life. A critical step during limb regeneration is formation of a blastema, which gives rise to the new extremity. Salamander limb regeneration has historically been tightly linked to the term dedifferentiation, however, with refined research tools it is important to revisit the definition of dedifferentiation in the context. To what extent do differentiated cells revert their differentiated phenotypes? To what extent do progeny from differentiated cells cross lineage boundaries during regeneration? How do cell cycle plasticity and lineage plasticity relate to each other? What is the relationship between dedifferentiation of specialized cells and activation of tissue resident stem cells in terms of their contribution to the new limb? Here we highlight these problems through the case of skeletal muscle.

  14. Zika Linked to Deformed Limbs in Newborns

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160324.html Zika Linked to Deformed Limbs in Newborns Cause isn' ... 2016 TUESDAY, Aug. 9, 2016 (HealthDay News) -- The Zika virus has already been linked to serious birth ...

  15. Gait termination in lower limb amputees

    NARCIS (Netherlands)

    Vrieling, A. H.; van Keeken, H. G.; Schoppen, T.; Otten, E.; Halbertsma, J. P. K.; Hof, A. L.; Postema, K.

    2008-01-01

    Objective: To study the limitations in function and adjustment strategies of lower limb amputees in gait termination. Design: Observational cohort study. Setting: University Medical Centre. Participants: Unilateral transfemoral and transtibial amputees, and able-bodied control subjects. Main outcome

  16. Upper limb prosthetic use in Slovenia.

    Science.gov (United States)

    Burger, H; Marincek, C

    1994-04-01

    The article deals with the use of different types of upper limb prostheses in Slovenia. Four hundred and fourteen upper limb amputees were sent a questionnaire on the type of their prosthesis, its use and reasons for non-use, respectively. The replies were subject to statistical analysis. Most of the questioned upper limb amputees (70%) wear a prosthesis only for cosmesis. The use of a prosthesis depends on the level of upper limb amputation, loss of the dominant hand, and time from amputation. Prosthetic success appears to be unrelated to age at the time of amputation and the rehabilitation programme. The most frequent reason for not wearing a prosthesis is heat and consequent sweating of the stump. More than a third of amputees are dissatisfied with their prostheses.

  17. Artificial vision workbench.

    Science.gov (United States)

    Frenger, P

    1997-01-01

    Machine vision is an important component of medical systems engineering. Inexpensive miniature solid state cameras are now available. This paper describes how these devices can be used as artificial retinas, to take snapshots and moving pictures in monochrome or color. Used in pairs, they produce a stereoscopic field of vision and enable depth perception. Macular and peripheral vision can be simulated electronically. This paper also presents the author's design of an artificial orbit for this synthetic eye. The orbit supports the eye, protects it, and provides attachment points for the ocular motion control system. Convergence and image fusion can be produced, and saccades simulated, along with the other ocular motions. The use of lenses, filters, irises and focusing mechanisms are also discussed. Typical camera-computer interfaces are described, including the use of "frame grabbers" and analog-to-digital image conversion. Software programs for eye positioning, image manipulation, feature extraction and object recognition are discussed, including the application of artificial neural networks.

  18. Artificial intelligence in nanotechnology.

    Science.gov (United States)

    Sacha, G M; Varona, P

    2013-11-15

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines.

  19. Artificial muscles on heat

    Science.gov (United States)

    McKay, Thomas G.; Shin, Dong Ki; Percy, Steven; Knight, Chris; McGarry, Scott; Anderson, Iain A.

    2014-03-01

    Many devices and processes produce low grade waste heat. Some of these include combustion engines, electrical circuits, biological processes and industrial processes. To harvest this heat energy thermoelectric devices, using the Seebeck effect, are commonly used. However, these devices have limitations in efficiency, and usable voltage. This paper investigates the viability of a Stirling engine coupled to an artificial muscle energy harvester to efficiently convert heat energy into electrical energy. The results present the testing of the prototype generator which produced 200 μW when operating at 75°C. Pathways for improved performance are discussed which include optimising the electronic control of the artificial muscle, adjusting the mechanical properties of the artificial muscle to work optimally with the remainder of the system, good sealing, and tuning the resonance of the displacer to minimise the power required to drive it.

  20. Artificial intelligence in nanotechnology

    Science.gov (United States)

    Sacha, G. M.; Varona, P.

    2013-11-01

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines.

  1. Artificial organ engineering

    CERN Document Server

    Annesini, Maria Cristina; Piemonte, Vincenzo; Turchetti, Luca

    2017-01-01

    Artificial organs may be considered as small-scale process plants, in which heat, mass and momentum transfer operations and, possibly, chemical transformations are carried out. This book proposes a novel analysis of artificial organs based on the typical bottom-up approach used in process engineering. Starting from a description of the fundamental physico-chemical phenomena involved in the process, the whole system is rebuilt as an interconnected ensemble of elemental unit operations. Each artificial organ is presented with a short introduction provided by expert clinicians. Devices commonly used in clinical practice are reviewed and their performance is assessed and compared by using a mathematical model based approach. Whilst mathematical modelling is a fundamental tool for quantitative descriptions of clinical devices, models are kept simple to remain focused on the essential features of each process. Postgraduate students and researchers in the field of chemical and biomedical engineering will find that t...

  2. 21 CFR 890.3500 - External assembled lower limb prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External assembled lower limb prosthesis. 890.3500... External assembled lower limb prosthesis. (a) Identification. An external assembled lower limb prosthesis... the lower extremity. Examples of external assembled lower limb prostheses are the following:...

  3. The limb-girdle muscular dystrophies.

    Science.gov (United States)

    Wicklund, Matthew P; Kissel, John T

    2014-08-01

    A collection of more than 30 genetic muscle diseases that share certain key features, limb-girdle muscular dystrophies are characterized by progressive weakness and muscle atrophy of the hips, shoulders, and proximal extremity muscles with postnatal onset. This article discusses clinical, laboratory, and histologic features of the 6 most prevalent limb-girdle dystrophies. In this large group of disorders, certain distinctive features often can guide clinicians to a correct diagnosis.

  4. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2003-01-01

    As the power of Bayesian techniques has become more fully realized, the field of artificial intelligence has embraced Bayesian methodology and integrated it to the point where an introduction to Bayesian techniques is now a core course in many computer science programs. Unlike other books on the subject, Bayesian Artificial Intelligence keeps mathematical detail to a minimum and covers a broad range of topics. The authors integrate all of Bayesian net technology and learning Bayesian net technology and apply them both to knowledge engineering. They emphasize understanding and intuition but also provide the algorithms and technical background needed for applications. Software, exercises, and solutions are available on the authors' website.

  5. Artificial human vision.

    Science.gov (United States)

    Dowling, Jason

    2005-01-01

    Can vision be restored to the blind? As early as 1929 it was discovered that stimulating the visual cortex of an individual led to the perception of spots of light, known as phosphenes [1] . The aim of artificial human vision systems is to attempt to utilize the perception of phosphenes to provide a useful substitute for normal vision. Currently, four locations for electrical stimulation are being investigated; behind the retina (subretinal), in front of the retina (epiretinal), the optic nerve and the visual cortex (using intra- and surface electrodes). This review discusses artificial human vision technology and requirements, and reviews the current development projects.

  6. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  7. General artificial neuron

    Science.gov (United States)

    Degeratu, Vasile; Schiopu, Paul; Degeratu, Stefania

    2007-05-01

    In this paper the authors present a model of artificial neuron named the general artificial neuron. Depending on application this neuron can change self number of inputs, the type of inputs (from excitatory in inhibitory or vice versa), the synaptic weights, the threshold, the type of intensifying functions. It is achieved into optoelectronic technology. Also, into optoelectronic technology a model of general McCulloch-Pitts neuron is showed. The advantages of these neurons are very high because we have to solve different applications with the same neural network, achieved from these neurons, named general neural network.

  8. A Robot Hand Testbed Designed for Enhancing Embodiment and Functional Neurorehabilitation of Body Schema in Subjects with Upper Limb Impairment or Loss

    Science.gov (United States)

    Hellman, Randall B.; Chang, Eric; Tanner, Justin; Helms Tillery, Stephen I.; Santos, Veronica J.

    2015-01-01

    Many upper limb amputees experience an incessant, post-amputation “phantom limb pain” and report that their missing limbs feel paralyzed in an uncomfortable posture. One hypothesis is that efferent commands no longer generate expected afferent signals, such as proprioceptive feedback from changes in limb configuration, and that the mismatch of motor commands and visual feedback is interpreted as pain. Non-invasive therapeutic techniques for treating phantom limb pain, such as mirror visual feedback (MVF), rely on visualizations of postural changes. Advances in neural interfaces for artificial sensory feedback now make it possible to combine MVF with a high-tech “rubber hand” illusion, in which subjects develop a sense of embodiment with a fake hand when subjected to congruent visual and somatosensory feedback. We discuss clinical benefits that could arise from the confluence of known concepts such as MVF and the rubber hand illusion, and new technologies such as neural interfaces for sensory feedback and highly sensorized robot hand testbeds, such as the “BairClaw” presented here. Our multi-articulating, anthropomorphic robot testbed can be used to study proprioceptive and tactile sensory stimuli during physical finger–object interactions. Conceived for artificial grasp, manipulation, and haptic exploration, the BairClaw could also be used for future studies on the neurorehabilitation of somatosensory disorders due to upper limb impairment or loss. A remote actuation system enables the modular control of tendon-driven hands. The artificial proprioception system enables direct measurement of joint angles and tendon tensions while temperature, vibration, and skin deformation are provided by a multimodal tactile sensor. The provision of multimodal sensory feedback that is spatiotemporally consistent with commanded actions could lead to benefits such as reduced phantom limb pain, and increased prosthesis use due to improved functionality and reduced

  9. A robot hand testbed designed for enhancing embodiment and functional neurorehabilitation of body schema in subjects with upper limb impairment or loss.

    Science.gov (United States)

    Hellman, Randall B; Chang, Eric; Tanner, Justin; Helms Tillery, Stephen I; Santos, Veronica J

    2015-01-01

    Many upper limb amputees experience an incessant, post-amputation "phantom limb pain" and report that their missing limbs feel paralyzed in an uncomfortable posture. One hypothesis is that efferent commands no longer generate expected afferent signals, such as proprioceptive feedback from changes in limb configuration, and that the mismatch of motor commands and visual feedback is interpreted as pain. Non-invasive therapeutic techniques for treating phantom limb pain, such as mirror visual feedback (MVF), rely on visualizations of postural changes. Advances in neural interfaces for artificial sensory feedback now make it possible to combine MVF with a high-tech "rubber hand" illusion, in which subjects develop a sense of embodiment with a fake hand when subjected to congruent visual and somatosensory feedback. We discuss clinical benefits that could arise from the confluence of known concepts such as MVF and the rubber hand illusion, and new technologies such as neural interfaces for sensory feedback and highly sensorized robot hand testbeds, such as the "BairClaw" presented here. Our multi-articulating, anthropomorphic robot testbed can be used to study proprioceptive and tactile sensory stimuli during physical finger-object interactions. Conceived for artificial grasp, manipulation, and haptic exploration, the BairClaw could also be used for future studies on the neurorehabilitation of somatosensory disorders due to upper limb impairment or loss. A remote actuation system enables the modular control of tendon-driven hands. The artificial proprioception system enables direct measurement of joint angles and tendon tensions while temperature, vibration, and skin deformation are provided by a multimodal tactile sensor. The provision of multimodal sensory feedback that is spatiotemporally consistent with commanded actions could lead to benefits such as reduced phantom limb pain, and increased prosthesis use due to improved functionality and reduced cognitive burden.

  10. A robot hand testbed designed for enhancing embodiment and functional neurorehabilitation of body schema in subjects with upper limb impairment or loss

    Directory of Open Access Journals (Sweden)

    Randall B. Hellman

    2015-02-01

    Full Text Available Many upper limb amputees experience an incessant, post-amputation phantom limb pain and report that their missing limbs feel paralyzed in an uncomfortable posture. One hypothesis is that efferent commands no longer generate expected afferent signals, such as proprioceptive feedback from changes in limb configuration, and that the mismatch of motor commands and visual feedback is interpreted as pain. Non-invasive therapeutic techniques for treating phantom limb pain, such as mirror visual feedback (MVF, rely on visualizations of postural changes. Advances in neural interfaces for artificial sensory feedback now make it possible to combine MVF with a high-tech rubber hand illusion, in which subjects develop a sense of embodiment with a fake hand when subjected to congruent visual and somatosensory feedback. We discuss clinical benefits that could arise from the confluence of known concepts such as MVF and the rubber hand illusion, and new technologies such as neural interfaces for sensory feedback and highly sensorized robot hand testbeds, such as the BairClaw presented here. Our multi-articulating, anthropomorphic robot testbed can be used to study proprioceptive and tactile sensory stimuli during physical finger-object interactions. Conceived for artificial grasp, manipulation, and haptic exploration, the BairClaw could also be used for future studies on the neurorehabilitation of somatosensory disorders due to upper limb impairment or loss. A remote actuation system enables the modular control of tendon-driven hands. The artificial proprioception system enables direct measurement of joint angles and tendon tensions while temperature, vibration, and skin deformation are provided by a multimodal tactile sensor. The provision of multimodal sensory feedback that is spatiotemporally consistent with commanded actions could lead to benefits such as reduced phantom limb pain, and increased prosthesis use due to improved functionality and reduced

  11. LIMB Demonstration Project Extension and Coolside Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Goots, T.R.; DePero, M.J.; Nolan, P.S.

    1992-11-10

    This report presents results from the limestone Injection Multistage Burner (LIMB) Demonstration Project Extension. LIMB is a furnace sorbent injection technology designed for the reduction of sulfur dioxide (SO[sub 2]) and nitrogen oxides (NO[sub x]) emissions from coal-fired utility boilers. The testing was conducted on the 105 Mwe, coal-fired, Unit 4 boiler at Ohio Edison's Edgewater Station in Lorain, Ohio. In addition to the LIMB Extension activities, the overall project included demonstration of the Coolside process for S0[sub 2] removal for which a separate report has been issued. The primary purpose of the DOE LIMB Extension testing, was to demonstrate the generic applicability of LIMB technology. The program sought to characterize the S0[sub 2] emissions that result when various calcium-based sorbents are injected into the furnace, while burning coals having sulfur content ranging from 1.6 to 3.8 weight percent. The four sorbents used included calcitic limestone, dolomitic hydrated lime, calcitic hydrated lime, and calcitic hydrated lime with a small amount of added calcium lignosulfonate. The results include those obtained for the various coal/sorbent combinations and the effects of the LIMB process on boiler and plant operations.

  12. Limb apraxia in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Rapaić Dragan

    2014-01-01

    Full Text Available Background/Aim. There are almost no studies on apraxia in people with multiple sclerosis. Although the white matter is damaged in MS, it is not the only location in which the pathological changes are present. Demyelinated lesions in the cortex have recently been recognized as important components of multiple sclerosis pathology. The aim of this study was to determine whether apraxia is present among people with MS, and the importance of demographic characteristics and impairment of functional systems at conceptualization and execution of movements. Methods. The experimental group consisted of 30 patients, mean age 51.34 ± 7.70 years. The patients in the experimental group were diagnosed with MS according to the McDonald criteria. The control group consisted of 30 healthy subjects, mean age 50.30 ± 10.47 years. For research purposes, we used the following instruments: Questionnaire for Collecting Demographic Data, Kurtzke Functional Systems Scores, Waterloo-Sunnybrook Apraxia Battery (WatAB. Execution of motion tasks that are a part of the Watwere incorporated in the System for the Observation and Analysis of Motor Behavior. Results. Our study showed that limb apraxia was common in people with MS. Apraxia was present during pantomime in 26.70% of the patients, and during the imitation of movements in 44.80% of the patients. Gender, age, education level, duration of disease and a form of MS did not determine the quality of conceptualization and execution of movements. The time elapsed from the last exacerbation was a determinant of quality of executed movements. Impairments of functional systems predicted impairments of movement execution. The expanded disability scale score correlated with the severity of apraxia. Conclusion. Our study confirm the presence of apraxia in MS. It is necessary to carry out further studies using functional magnetic resonance imaging, as well as the conduct longitudinal studies to determine the precise structure of

  13. Development of a residuum/socket interface simulator for lower limb prosthetics.

    Science.gov (United States)

    McGrath, Michael Paul; Gao, Jianliang; Tang, Jinghua; Laszczak, Piotr; Jiang, Liudi; Bader, Dan; Moser, David; Zahedi, Saeed

    2017-03-01

    Mechanical coupling at the interface between lower limb residua and prosthetic sockets plays an important role in assessing socket fitting and tissue health. However, most research lab-based lower limb prosthetic simulators to-date have implemented a rigid socket coupling. This study describes the fabrication and implementation of a lower limb residuum/socket interface simulator, designed to reproduce the forces and moments present during the key loading phases of amputee walking. An artificial residuum made with model bones encased in silicone was used, mimicking the compliant mechanical loading of a real residuum/socket interface. A 6-degree-of-freedom load cell measured the overall kinetics, having previously been incorporated into an amputee's prosthesis to collect reference data. The developed simulator was compared to a setup where a rigid pylon replaced the artificial residuum. A maximum uniaxial load of 850 N was applied, comparable to the peak vertical ground reaction force component during amputee walking. Load cell outputs from both pylon and residuum setups were compared. During weight acceptance, when including the artificial residuum, compression decreased by 10%, while during push off, sagittal bending and anterior-posterior shear showed a 25% increase and 34% decrease, respectively. Such notable difference by including a compliant residuum further highlighted the need for such an interface simulator. Subsequently, the simulator was adjusted to produce key load cell outputs briefly aligning with those from amputee walking. Force sensing resistors were deployed at load bearing anatomic locations on the residuum/socket interface to measure pressures and were compared to those cited in the literature for similar locations. The development of such a novel simulator provides an objective adjunct, using commonly available mechanical test machines. It could potentially be used to provide further insight into socket design, fit and the complex load

  14. Micromachined Artificial Haircell

    Science.gov (United States)

    Liu, Chang (Inventor); Engel, Jonathan (Inventor); Chen, Nannan (Inventor); Chen, Jack (Inventor)

    2010-01-01

    A micromachined artificial sensor comprises a support coupled to and movable with respect to a substrate. A polymer, high-aspect ratio cilia-like structure is disposed on and extends out-of-plane from the support. A strain detector is disposed with respect to the support to detect movement of the support.

  15. Artificial Gravity Research Plan

    Science.gov (United States)

    Gilbert, Charlene

    2014-01-01

    This document describes the forward working plan to identify what countermeasure resources are needed for a vehicle with an artificial gravity module (intermittent centrifugation) and what Countermeasure Resources are needed for a rotating transit vehicle (continuous centrifugation) to minimize the effects of microgravity to Mars Exploration crewmembers.

  16. Artificial Left Ventricle

    CERN Document Server

    Ranjbar, Saeed; Meybodi, Mahmood Emami

    2014-01-01

    This Artificial left ventricle is based on a simple conic assumption shape for left ventricle where its motion is made by attached compressed elastic tubes to its walls which are regarded to electrical points at each nodal .This compressed tubes are playing the role of myofibers in the myocardium of the left ventricle. These elastic tubes have helical shapes and are transacting on these helical bands dynamically. At this invention we give an algorithm of this artificial left ventricle construction that of course the effect of the blood flow in LV is observed with making beneficiary used of sensors to obtain this effecting, something like to lifegates problem. The main problem is to evaluate powers that are interacted between elastic body (left ventricle) and fluid (blood). The main goal of this invention is to show that artificial heart is not just a pump, but mechanical modeling of LV wall and its interaction with blood in it (blood movement modeling) can introduce an artificial heart closed to natural heart...

  17. Artificial intelligence and psychiatry.

    Science.gov (United States)

    Servan-Schreiber, D

    1986-04-01

    This paper provides a brief historical introduction to the new field of artificial intelligence and describes some applications to psychiatry. It focuses on two successful programs: a model of paranoid processes and an expert system for the pharmacological management of depressive disorders. Finally, it reviews evidence in favor of computerized psychotherapy and offers speculations on the future development of research in this area.

  18. Observations of artificial satellites

    Directory of Open Access Journals (Sweden)

    A. MAMMANO

    1964-06-01

    Full Text Available The following publication gives the results of photographic
    observations of artificial satellites made at Asiago during the second
    and third year of this programme. The fixed camera technique and that
    with moving film (the latter still in its experimental stage have been used.

  19. Artificial intelligence within AFSC

    Science.gov (United States)

    Gersh, Mark A.

    1990-01-01

    Information on artificial intelligence research in the Air Force Systems Command is given in viewgraph form. Specific research that is being conducted at the Rome Air Development Center, the Space Technology Center, the Human Resources Laboratory, the Armstrong Aerospace Medical Research Laboratory, the Armamant Laboratory, and the Wright Research and Development Center is noted.

  20. Introduction to Artificial Neural Networks

    DEFF Research Database (Denmark)

    Larsen, Jan

    1999-01-01

    The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks.......The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks....

  1. Moving a generalised limb : a simulation with consequences for theories on limb control

    NARCIS (Netherlands)

    Otten, E

    2005-01-01

    The movement control of articulated limbs in vertebrates has been explained in terms of equilibrium points and moving equilibrium points or virtual trajectories. These hypotheses state that the nervous system makes the control Of multi-segment limbs easier by simply planning in terms of these equili

  2. Effects of varying inter-limb spacing to limb length ratio in metachronal swimming

    Science.gov (United States)

    Lai, Hong Kuan; Merkel, Rachael; Santhanakrishnan, Arvind

    2016-11-01

    Crustaceans such as shrimp, krill and crayfish swim by rhythmic paddling of four to five pairs of closely spaced limbs. Each pair is phase-shifted in time relative to the neighboring pair, resulting in a metachronal wave that travels in the direction of animal motion. The broad goal of this study is to investigate how the mechanical design of the swimming limbs affect scalability of metachronal swimming in terms of limb-based Reynolds number (Re). A scaled robotic model of metachronal paddling was developed, consisting of four pairs of hinged acrylic plates actuated using stepper motors that were immersed in a rectangular tank containing water-glycerin fluid medium. 2D PIV measurements show that the propulsive jets transition from being primarily horizontal (thrust-producing direction) at Re of order 10 to angled vertically at Re of order 100. The ratio of inter-limb spacing to limb length among metachronal swimming organisms ranges between 0.2 to 0.65. 2D PIV will be used to examine the jets generated between adjacent limbs for varying inter-limb spacing to limb length ratios. The effect of increasing this ratio to beyond the biologically observed range will be discussed.

  3. Reorganization of gait after limb-saving surgery of the lower limb

    NARCIS (Netherlands)

    de Visser, E; Veth, RPH; Schreuder, HWB; Duysens, J; Mulder, T

    2003-01-01

    Objective: In this study, the concept of a cognitive dual-task performance and visual restriction during walking has been used to study the recovery of gait after limb-saving surgery in ten patients. Design: All patients were recovering from some form of treatment to tumors of the lower limbs. Patie

  4. Functional trade-offs in the limb bones of dogs selected for running versus fighting.

    Science.gov (United States)

    Kemp, T J; Bachus, K N; Nairn, J A; Carrier, D R

    2005-09-01

    The physical demands of rapid and economical running differ from the demands of fighting in ways that may prevent the simultaneous evolution of optimal performance in these two behaviors. Here, we test an hypothesis of functional trade-off in limb bones by measuring mechanical properties of limb bones in two breeds of domestic dog (Canis lupus familiaris L.) that have undergone intense artificial selection for running (greyhound) and fighting (pit bull) performance. The bones were loaded to fracture in three-point static bending. To correct for the effect of shear, we estimated the shear stress in the cross section and added energy due to shear stress to the tensile energy. The proximal limb bones of the pit bulls differed from those of the greyhounds in having relatively larger second moments of area of mid-diaphyseal cross sections and in having more circular cross-sectional shape. The pit bulls exhibited lower stresses at yield, had lower elastic moduli and failed at much higher levels of work. The stiffness of the tissue of the humerus, radius, femur and tibia was 1.5-2.4-fold greater in the greyhounds than in the pit bulls. These bones from the pit bulls absorbed 1.9-2.6-fold more energy before failure than did those of the greyhounds. These differences between breeds were not observed in the long bones of the feet, metacarpals and metatarsals. Nevertheless, the results of this analysis suggest that selection for high-speed running is associated with the evolution of relatively stiff, brittle limb bones, whereas selection for fighting performance leads to the evolution of limb bones with relatively high resistance to failure.

  5. Pharmacological interventions for phantom limb pain

    Institute of Scientific and Technical Information of China (English)

    FANG Jun; LIAN Yan-hong; XIE Kang-jie; CAI Shu-nü

    2013-01-01

    Objective To review the mechanisms and current clinical application of pharmacological interventions for phantom limb pain.Data sources Both Chinese and English language literatures were searched using MEDLINE (1982-2011),Pubmed (1982-2011) and the Index of Chinese Language Literature (1982-2011).Study selection Data from published articles about pharmacological management of phantom limb pain in recent domestic and foreign literature were selected.Data extraction Data were mainly extracted from 96 articles which are listed in the reference section of this review.Results By reviewing the mechanisms and current clinical application of pharmacological interventions for phantom limb pain,including anticonvulsants,antidepressants,local anaesthetics,N-methyl-D-aspartate receptor antagonists,non-steroidal anti-inflammatory drugs,tramadol,opioids,calcitonin,capsaicin,beta-adrenergic blockers,clonidine,muscle relaxants,and emerging drugs,we examined the efficacy and safety of these medications,outlined the limitations and future directions.Conclusions Although there is lack of evidence-based consensus guidelines for the pharmacological management of phantom limb pain,we recommend tricyclic antidepressants,gabapentin,tramadol,opioids,local anaesthetics and N-methyl-D-aspartate receptor antagonists as the rational options for the treatment of phantom limb pain.

  6. Phantom Limb Pain: Mechanisms and Treatment Approaches

    Directory of Open Access Journals (Sweden)

    Bishnu Subedi

    2011-01-01

    Full Text Available The vast amount of research over the past decades has significantly added to our knowledge of phantom limb pain. Multiple factors including site of amputation or presence of preamputation pain have been found to have a positive correlation with the development of phantom limb pain. The paradigms of proposed mechanisms have shifted over the past years from the psychogenic theory to peripheral and central neural changes involving cortical reorganization. More recently, the role of mirror neurons in the brain has been proposed in the generation of phantom pain. A wide variety of treatment approaches have been employed, but mechanism-based specific treatment guidelines are yet to evolve. Phantom limb pain is considered a neuropathic pain, and most treatment recommendations are based on recommendations for neuropathic pain syndromes. Mirror therapy, a relatively recently proposed therapy for phantom limb pain, has mixed results in randomized controlled trials. Most successful treatment outcomes include multidisciplinary measures. This paper attempts to review and summarize recent research relative to the proposed mechanisms of and treatments for phantom limb pain.

  7. Alignment of lower-limb prostheses.

    Science.gov (United States)

    Zahedi, M S; Spence, W D; Solomonidis, S E; Paul, J P

    1986-04-01

    Alignment of a prosthesis is defined as the position of the socket relative to the other prosthetic components of the limb. During dynamic alignment the prosthetist, using subjective judgment and feedback from the patient, aims to achieve the most suitable limb geometry for best function and comfort. Until recently it was generally believed that a patient could only be satisfied with a unique "optimum alignment." The purpose of this systematic study of lower-limb alignment parameters was to gain an understanding of the factors that make a limb configuration or optimum alignment, acceptable to the patient, and to obtain a measure of the variation of this alignment that would be acceptable to the amputee. In this paper, the acceptable range of alignments for 10 below- and 10 above-knee amputees are established. Three prosthetists were involved in the majority of the 183 below-knee and 100 above-knee fittings, although several other prosthetists were also involved. The effects of each different prosthetist on the established range of alignment for each patient are reported to be significant. It is now established that an amputee can tolerate several alignments ranging in some parameters by as much as 148 mm in shifts and 17 degrees in tilts. This paper describes the method of defining and measuring the alignment of lower-limb prostheses. It presents quantitatively established values for bench alignment position and the range of adjustment required for incorporation into the design of new alignment units.

  8. Neck muscle fatigue alters upper limb proprioception.

    Science.gov (United States)

    Zabihhosseinian, Mahboobeh; Holmes, Michael W R; Murphy, Bernadette

    2015-05-01

    Limb proprioception is an awareness by the central nervous system (CNS) of the location of a limb in three-dimensional space and is essential for movement and postural control. The CNS uses the position of the head and neck when interpreting the position of the upper limb, and altered input from neck muscles may affect the sensory inputs to the CNS and consequently may impair the awareness of upper limb joint position. The purpose of this study was to determine whether fatigue of the cervical extensors muscles (CEM) using a submaximal fatigue protocol alters the ability to recreate a previously presented elbow angle with the head in a neutral position. Twelve healthy individuals participated. CEM activity was examined bilaterally using surface electromyography, and kinematics of the elbow joint was measured. The fatigue protocol included an isometric neck extension task at 70 % of maximum until failure. Joint position error increased following fatigue, demonstrating a significant main effect of time (F 2, 18 = 19.41, p ≤ 0.0001) for absolute error. No significant differences were found for variable error (F 2, 18 = 0.27, p = 0.76) or constant error (F 2, 18 = 1.16 of time, p ≤ 0.33). This study confirms that fatigue of the CEM can reduce the accuracy of elbow joint position matching. This suggests that altered afferent input from the neck subsequent to fatigue may impair upper limb proprioception.

  9. Climbing robot actuated by meso-hydraulic artificial muscles

    Science.gov (United States)

    Bryant, Matthew; Fitzgerald, Jason; Miller, Samuel; Saltzman, Jonah; Kim, Sangkyu; Lin, Yong; Garcia, Ephrahim

    2014-03-01

    This paper presents the design, construction, experimental characterization, and system testing of a legged, wall-climbing robot actuated by meso-scale hydraulic artificial muscles. While small wall-climbing robots have seen increased research attention in recent years, most authors have primarily focused on designs for the gripping and adhesion of the robot to the wall, while using only standard DC servo-motors for actuation. This project seeks to explore and demonstrate a different actuation mechanism that utilizes hydraulic artificial muscles. A four-limb climbing robot platform that includes a full closed-loop hydraulic power and control system, custom hydraulic artificial muscles for actuation, an on-board microcontroller and RF receiver for control, and compliant claws with integrated sensing for gripping a variety of wall surfaces has been constructed and is currently being tested to investigate this actuation method. On-board power consumption data-logging during climbing operation, analysis of the robot kinematics and climbing behavior, and artificial muscle force-displacement characterization are presented to investigate and this actuation method.

  10. Artificial Enzymes, "Chemzymes"

    DEFF Research Database (Denmark)

    Bjerre, Jeannette; Rousseau, Cyril Andre Raphaël; Pedersen, Lavinia Georgeta M;

    2008-01-01

    Enzymes have fascinated scientists since their discovery and, over some decades, one aim in organic chemistry has been the creation of molecules that mimic the active sites of enzymes and promote catalysis. Nevertheless, even today, there are relatively few examples of enzyme models...... that successfully perform Michaelis-Menten catalysis under enzymatic conditions (i.e., aqueous medium, neutral pH, ambient temperature) and for those that do, very high rate accelerations are seldomly seen. This review will provide a brief summary of the recent developments in artificial enzymes, so called...... "Chemzymes", based on cyclodextrins and other molecules. Only the chemzymes that have shown enzyme-like activity that has been quantified by different methods will be mentioned. This review will summarize the work done in the field of artificial glycosidases, oxidases, epoxidases, and esterases, as well...

  11. Artificial neural network modelling

    CERN Document Server

    Samarasinghe, Sandhya

    2016-01-01

    This book covers theoretical aspects as well as recent innovative applications of Artificial Neural networks (ANNs) in natural, environmental, biological, social, industrial and automated systems. It presents recent results of ANNs in modelling small, large and complex systems under three categories, namely, 1) Networks, Structure Optimisation, Robustness and Stochasticity 2) Advances in Modelling Biological and Environmental Systems and 3) Advances in Modelling Social and Economic Systems. The book aims at serving undergraduates, postgraduates and researchers in ANN computational modelling. .

  12. Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Kapil Nahar

    2012-12-01

    Full Text Available An artificial neural network is an information-processing paradigm that is inspired by the way biological nervous systems, such as the brain, process information.The key element of this paradigm is the novel structure of the information processing system. It is composed of a large number of highly interconnected processing elements (neurons working in unison to solve specific problems.Ann’s, like people, learn by example.

  13. Essentials of artificial intelligence

    CERN Document Server

    Ginsberg, Matt

    1993-01-01

    Since its publication, Essentials of Artificial Intelligence has beenadopted at numerous universities and colleges offering introductory AIcourses at the graduate and undergraduate levels. Based on the author'scourse at Stanford University, the book is an integrated, cohesiveintroduction to the field. The author has a fresh, entertaining writingstyle that combines clear presentations with humor and AI anecdotes. At thesame time, as an active AI researcher, he presents the materialauthoritatively and with insight that reflects a contemporary, first hand

  14. Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Kapil Nahar

    2012-12-01

    Full Text Available An artificial neural network is an information-processing paradigm that is inspired by the way biological nervous systems, such as the brain, process information. The key element of this paradigm is the novel structure of the information processing system. It is composed of a large number of highly interconnected processing elements (neurons working in unison to solve specific problems. Ann’s, like people, learn by example.

  15. Endovascular management of acute limb ischemia.

    Science.gov (United States)

    Peeters, P; Verbist, J; Keirse, K; Deloose, K; Bosiers, M

    2010-06-01

    Acute limb ischemia (ALI) refers to a rapid worsening of limb perfusion resulting in rest pain, ischemic ulcers or gangrene. With an estimated incidence of 140 million/year, ALI is serious limb-threatening and life-threatening medical emergency demanding prompt action. Three prospective, randomized clinical trials provide data on trombolytic therapy versus surgical intervention in patients with acute lower extremity ischemia. Although they did not give us the final answer, satisfactory results are reported for percutaneous thrombolysis compared with surgery. Moreover, they suggest an important advantage of thrombolysis in acute bypass graft occlusions. Therefore, we believe thrombolytic therapy should be a part of the vascular surgeon's armamentarium to safely and successfully treat ALI patients.

  16. Cross-limb Interference during motor learning

    DEFF Research Database (Denmark)

    Lauber, Benedikt; Jensen, Jesper Lundbye; Keller, Martin

    2013-01-01

    It is well known that following skill learning, improvements in motor performance may transfer to the untrained contralateral limb. It is also well known that retention of a newly learned task A can be degraded when learning a competing task B that takes place directly after learning A. Here we....... Importantly, the interference effect in the untrained limb was dependent on the level of skill acquisition in the interfering motor task. These behavioural results of the untrained limb were accompanied by training specific changes in corticospinal excitability, which increased for the hemisphere ipsilateral...... to the trained hand following ballistic training and decreased during accuracy training of the ipsilateral hand. The results demonstrate that contralateral interference effects may occur, and that interference depends on the level of skill acquisition in the interfering motor task. This finding might...

  17. Automatic identification for standing tree limb pruning

    Institute of Scientific and Technical Information of China (English)

    Sun Renshan; Li Wenbin; Tian Yongchen; Hua Li

    2006-01-01

    To meet the demand of automatic pruning machines,this paper presents a new method for dynamic automatic identification of standing tree limbs and capture of the digital images of Platycladus orientalis.Methods of computer vision,image processing and wavelet analysis technology were used to compress,filter,segment,abate noise and capture the outline of the picture.We then present the arithmetic for dynamic automatic identification of standing tree limbs,extracting basic growth characteristics of the standing trees such as the form,size,degree of bending and their relative spatial position.We use pattern recognition technology to confirm the proportionate relationship matching the database and thus achieve the goal of dynamic automatic identification of standing tree limbs.

  18. Artificial sweetener; Jinko kanmiryo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-08-01

    The patents related to the artificial sweetener that it is introduced to the public in 3 years from 1996 until 1998 are 115 cases. The sugar quality which makes an oligosaccharide and sugar alcohol the subject is greatly over 28 cases of the non-sugar quality in the one by the kind as a general tendency of these patents at 73 cases in such cases as the Aspartame. The method of manufacture patent, which included new material around other peptides, the oligosaccharide and sugar alcohol isn`t inferior to 56 cases of the formation thing patent at 43 cases, and pays attention to the thing, which is many by the method of manufacture, formation. There is most improvement of the quality of sweetness with 31 cases in badness of the aftertaste which is characteristic of the artificial sweetener and so on, and much stability including the improvement in the flavor of food by the artificial sweetener, a long time and dissolution, fluid nature and productivity and improvement of the economy such as a cost are seen with effect on a purpose. (NEDO)

  19. ARTIFICIAL INSEMINATION IN BOVINE

    Directory of Open Access Journals (Sweden)

    A. L. M Marinho

    2016-02-01

    Full Text Available This literature review aims to show the main scientific advances achieved in the area of Artificial Insemination (AI within animal reproduction and how these can improve reproductive efficiency and productive of the Brazilian cattle herd. With knowledge of the mechanisms involved in the control of reproductive physiology, in levels endocrine, cellular and molecular, it was possible the development of reproductive biotechnologies, standing out the IA, It has been used on a large scale, by allow the multiplication of animals superior genetically , increase the birthrate and be particularly effective in adjusting the breeding season in cattle. Artificial insemination has an important role in animal genetic improvement; it is the main and more viable middle of spread of genes worldwide when compared to other methods how technologies of embryos and the natural breeding. There are several advantages in using artificial insemination in herd both of cutting as milkman, as herd genetic improvement in lesser time and at a low cost through the use of semen of demonstrably superior sires for production, well as in the control and decrease of diseases which entail reproductive losses and consequently productive, by allowing the creator The crossing of zebuine females with bulls of European breeds and vice-versa, through the use of semen, increasing the number of progeny of a reproducer superior

  20. Special Considerations for Multiple Limb Amputation.

    Science.gov (United States)

    Pasquina, Paul F; Miller, Matthew; Carvalho, A J; Corcoran, Michael; Vandersea, James; Johnson, Elizabeth; Chen, Yin-Ting

    2014-01-01

    It has been estimated that more than 1.6 million individuals in the United States have undergone at least one amputation. The literature abounds with research of the classifications of such injuries, their etiologies, epidemiologies, treatment regimens, average age of onset (average age of amputation), and much more. The subpopulation that is often overlooked in these evaluations, however, is comprised of individuals who have suffered multiple limb loss. The challenges faced by those with single-limb loss are amplified for those with multiple limb loss. Pain, lifestyle adjustment, and quality of life return are just a few key areas of concern in this population. Along with amputations resulting from trauma, many individuals with multiple amputations have endured them as a result of dysvascular disease. Over recent years, amputations as a result of dysvascular disease have risen to comprise more than 80 % of new amputations occurring in the United States every year. This compares to just 54 % of total current prevalence. Those with diabetes comorbid with dysvascular disease make up 74 % of those with dysvascular amputations, and these individuals with diabetes comorbid with dysvascular disease have a 55 % chance of enduring an amputation of their contralateral limb within 2-3 years of their initial amputation. With the well-documented aging of the nation's population and the similarly skyrocketing prevalence of dysvascular disease and diabetes, it can be expected that the number of individuals with multiple limb loss will continue to increase in the United States. This article outlines the recommended measures of care for this particular subpopulation, including pain management, behavioral health considerations, strategies for rehabilitation for various levels and variations of multiple limb loss, and the assistive technology and adaptive equipment that might be available for these individuals to best enable them to continue healthy, fulfilling lives following

  1. Lbx1 expression and frog limb development.

    Science.gov (United States)

    Sabo, Michelle C; Nath, Kimberly; Elinson, Richard P

    2009-12-01

    In order to identify prospective limb muscle cells in a frog, we cloned Lbx1 from the direct developing frog Eleutherodactylus coqui. Like in embryos of the frog Xenopus laevis but unlike in other vertebrates, EcLbx1 is expressed in all trunk somites. Like in embryos of chick, mouse, and zebrafish, cells expressing EcLbx1 are then found in limb buds, consistent with migration of those cells from somites. EcLbx1 is also expressed in the dorsal spinal cord as in other vertebrates.

  2. Cocaine-associated lower limb ischemia.

    LENUS (Irish Health Repository)

    Collins, Chris G

    2011-07-25

    Cocaine-associated thrombosis has been reported in the literature with reports of vascular injuries to cardiac, pulmonary, intestinal, placental, and musculoskeletal vessels; however, injury of the pedal vessels is rare. We report on a 31-year-old man who presented 2 months following a cocaine binge with limb-threatening ischemia without an otherwise identifiable embolic source. Angiography confirmed extensive occlusive disease of the tibioperoneal vessels. The patient improved following therapy with heparin and a prostacyclin analogue. Cocaine-induced thrombosis should be considered in patients presenting with acute arterial insufficiency in the lower limb without any other identifiable cause.

  3. Lower Limb Ischaemia Complicating Total Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Shiu-Wai Chan

    2012-06-01

    Full Text Available This article is about two patients having vascular injuries complicating total hip arthroplasty because of intraoperative indirect injuries. One patient had a delayed presentation of acute lower limb ischaemia, in which he required amputation of his left second toe because of ischaemic gangrene. The other patient had acute lower limb ischaemia leading to permanent muscle and nerve damage because of delayed recognition. Both patients had vascular interventions for the indirect vascular injuries. Preoperative workup for suspicious underlying peripheral vascular disease, intraoperative precautions, and perioperative period of vascular status monitoring are essential for prevention and early detection of such sinister events.

  4. Electrodiagnostic testing in diabetic neuropathy: Which limb?

    Science.gov (United States)

    Rota, E; Cocito, D

    2015-10-01

    Electrodiagnosis of subclinical diabetic neuropathies by nerve conduction studies remains challenging. The question arises about which nerves should be tested and what the best electrodiagnostic protocol to make an early diagnosis of diabetic neuropathies would be. On the basis of our findings and other evidence, which highlighted the remarkable prevalence of electrophysiological abnormalities in nerve conduction studies of the upper limbs, often in the presence of normal lower limb conduction parameters, we suggest that both ulnar and median nerves, in their motor and sensitive component, should be the two target nerves for electrodiagnostic protocols in diabetic neuropathies.

  5. Active upper limb prosthesis based on natural movement trajectories.

    Science.gov (United States)

    Ramírez-García, Alfredo; Leija, Lorenzo; Muñoz, Roberto

    2010-03-01

    The motion of the current prostheses is sequential and does not allow natural movements. In this work, complex natural motion patterns from a healthy upper limb were characterized in order to be emulated for a trans-humeral prosthesis with three degrees of freedom at the elbow. Firstly, it was necessary to define the prosthesis workspace, which means to establish a relationship using an artificial neural network (ANN), between the arm-forearm (3-D) angles allowed by the prosthesis, and its actuators length. The 3-D angles were measured between the forearm and each axis of the reference system attached at the elbow. Secondly, five activities of daily living (ADLs) were analyzed by means of the elbow flexion (EF), the forearm prono-supination (FPS) and the 3-D angles, from healthy subjects, by using a video-based motion analysis system. The 3-D angles were fed to the prosthesis model (ANN) in order to analyze which ADLs could be emulated by the prosthesis. As a result, a prosthesis kinematics approximation was obtained. In conclusion, in spite of the innovative mechanical configuration of the actuators, it was possible to carry out only three of the five ADLs considered. Future work will include improvement of the mechanical configuration of the prosthesis to have greater range of motion.

  6. HST observations of the limb polarization of Titan

    CERN Document Server

    Bazzon, Andreas; Buenzli, Esther

    2014-01-01

    Titan is an excellent test case for detailed studies of the scattering polarization from thick hazy atmospheres. We present the first limb polarization measurements of Titan, which are compared as a test to our limb polarization models. Previously unpublished imaging polarimetry from the HST archive is presented which resolves the disk of Titan. We determine flux-weighted averages of the limb polarization and radial limb polarization profiles, and investigate the degradation and cancelation effects in the polarization signal due to the limited spatial resolution of our observations. Taking this into account we derive corrected values for the limb polarization in Titan. The results are compared with limb polarization models, using atmosphere and haze scattering parameters from the literature. In the wavelength bands between 250 nm and 2000 nm a strong limb polarization of about 2-7 % is detected with a position angle perpendicular to the limb. The fractional polarization is highest around 1 micron. As a first ...

  7. Plasticity in the visual system is associated with prosthesis use in phantom limb pain

    Directory of Open Access Journals (Sweden)

    Sandra ePreißler

    2013-06-01

    Full Text Available The experience of strong phantom limb pain (PLP in arm amputees was previously shown to be associated with structural neural plasticity in parts of the cortex that belong to dorsal and ventral visual streams. It has been speculated that this plasticity results from the extensive use of a functional prosthesis which is associated with increased visual feedback to control the artificial hand.To test this hypothesis, we reanalyzed data of cortical volumes of 21 upper limb amputees and tested the association between the amount of use of the hand prosthesis and cortical volume plasticity.On the behavioral level, we found no relation between PLP and the amount of prosthesis use for the whole patient group. However, by subdividing the patient group into patients with strong PLP and those with low to medium PLP, stronger pain was significantly associated with less prosthesis use whereas the group with low PLP did not show such an association.Most plasticity of cortical volume was identified within the dorsal stream. The more the patients that suffered from strong PLP used their prosthesis, the smaller was the volume of their posterior parietal cortex.Our data indicate a relationship between prosthesis use and cortical plasticity of the visual stream. This plasticity might present a brain adaption process to new movement and coordination patterns needed to guide an artificial hand.

  8. Inducible limb-shaking transitory ischemic attacks

    DEFF Research Database (Denmark)

    Rosenbaum, Sverre; Ovesen, Christian; Futrell, Nancy

    2016-01-01

    with exercise-induced weakness associated with tremor in his right arm. His left internal carotid artery was occluded at the bifurcation. Administration of statin and antiplatelet did not relieve his symptoms, and his stereotypic, exercise-induced "limb-shaking" episodes persisted. He underwent successful...

  9. Limb disparity and wing shape in pterosaurs.

    Science.gov (United States)

    Dyke, G J; Nudds, R L; Rayner, J M V

    2006-07-01

    The limb proportions of the extinct flying pterosaurs were clearly distinct from their living counterparts, birds and bats. Within pterosaurs, however, we show that further differences in limb proportions exist between the two main groups: the clade of short-tailed Pterodactyloidea and the paraphyletic clades of long-tailed rhamphorhynchoids. The hindlimb to forelimb ratios of rhamphorhynchoid pterosaurs are similar to that seen in bats, whereas those of pterodactyloids are much higher. Such a clear difference in limb ratios indicates that the extent of the wing membrane in rhamphorhynchoids and pterodactyloids may also have differed; this is borne out by simple ternary analyses. Further, analyses also indicate that the limbs of Sordes pilosus, a well-preserved small taxon used as key evidence for inferring the extent and shape of the wing membrane in all pterosaurs, are not typical even of its closest relatives, other rhamphorhynchoids. Thus, a bat-like extensive hindlimb flight membrane, integrated with the feet and tail may be applicable only to a small subset of pterosaur diversity. The range of flight morphologies seen in these extinct reptiles may prove much broader than previously thought.

  10. Running With an Elastic Lower Limb Exoskeleton.

    Science.gov (United States)

    Cherry, Michael S; Kota, Sridhar; Young, Aaron; Ferris, Daniel P

    2016-06-01

    Although there have been many lower limb robotic exoskeletons that have been tested for human walking, few devices have been tested for assisting running. It is possible that a pseudo-passive elastic exoskeleton could benefit human running without the addition of electrical motors due to the spring-like behavior of the human leg. We developed an elastic lower limb exoskeleton that added stiffness in parallel with the entire lower limb. Six healthy, young subjects ran on a treadmill at 2.3 m/s with and without the exoskeleton. Although the exoskeleton was designed to provide ~50% of normal leg stiffness during running, it only provided 24% of leg stiffness during testing. The difference in added leg stiffness was primarily due to soft tissue compression and harness compliance decreasing exoskeleton displacement during stance. As a result, the exoskeleton only supported about 7% of the peak vertical ground reaction force. There was a significant increase in metabolic cost when running with the exoskeleton compared with running without the exoskeleton (ANOVA, P exoskeletons for human running are human-machine interface compliance and the extra lower limb inertia from the exoskeleton.

  11. 49 CFR 572.35 - Limbs.

    Science.gov (United States)

    2010-10-01

    ... OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Hybrid III Test Dummy § 572.35 Limbs. (a... between the foot and any other exterior surfaces. (iv) Place the longitudinal centerline of the test probe..., vertical or rotational movement at time zero. (vi) Impact the knee with the test probe so that...

  12. Limb reconstruction with the Ilizarov method

    NARCIS (Netherlands)

    Oostenbroek, H.J.

    2014-01-01

    In chapter 1, the background and origins of this study are explained. The aims of the study are defined. In chapter 2, an analysis of the complications rate of limb reconstruction in a cohort of 37 consecutive growing children was done. Several patient and deformity factors were investigated by logi

  13. Artificial intelligence in hematology.

    Science.gov (United States)

    Zini, Gina

    2005-10-01

    Artificial intelligence (AI) is a computer based science which aims to simulate human brain faculties using a computational system. A brief history of this new science goes from the creation of the first artificial neuron in 1943 to the first artificial neural network application to genetic algorithms. The potential for a similar technology in medicine has immediately been identified by scientists and researchers. The possibility to store and process all medical knowledge has made this technology very attractive to assist or even surpass clinicians in reaching a diagnosis. Applications of AI in medicine include devices applied to clinical diagnosis in neurology and cardiopulmonary diseases, as well as the use of expert or knowledge-based systems in routine clinical use for diagnosis, therapeutic management and for prognostic evaluation. Biological applications include genome sequencing or DNA gene expression microarrays, modeling gene networks, analysis and clustering of gene expression data, pattern recognition in DNA and proteins, protein structure prediction. In the field of hematology the first devices based on AI have been applied to the routine laboratory data management. New tools concern the differential diagnosis in specific diseases such as anemias, thalassemias and leukemias, based on neural networks trained with data from peripheral blood analysis. A revolution in cancer diagnosis, including the diagnosis of hematological malignancies, has been the introduction of the first microarray based and bioinformatic approach for molecular diagnosis: a systematic approach based on the monitoring of simultaneous expression of thousands of genes using DNA microarray, independently of previous biological knowledge, analysed using AI devices. Using gene profiling, the traditional diagnostic pathways move from clinical to molecular based diagnostic systems.

  14. One-sided limb preference is linked to alternating-limb locomotion in anuran amphibians.

    Science.gov (United States)

    Malashichev, Yegor B

    2006-11-01

    Amphibians provide a unique opportunity for identifying possible links between lateralized behaviors, locomotion, and phylogeny and for addressing the origin of lateralized behaviors of higher vertebrates. Five anuran species with different locomotive habits were tested for forelimb and hind limb preferences during 2 stereotyped behavior sequences--wiping a foreign object off their snout and righting themselves from the overturned position. The experiments were analyzed in a broader context of previous findings on anuran lateralization involving 11 anuran species that were studied within the same experimental paradigms. This analysis shows that one-sided forelimb and hind limb motor lateralization in anurans is strongly associated with alternating-limb locomotion and other unilateral limb activity. Conclusions reached for anuran amphibians may be applicable to other vertebrates possessing paired appendages-the degree of lateralization in motor response depends on the mode of locomotion used by a species.

  15. Polymer artificial muscles

    Directory of Open Access Journals (Sweden)

    Tissaphern Mirfakhrai

    2007-04-01

    Full Text Available The various types of natural muscle are incredible material systems that enable the production of large deformations by repetitive molecular motions. Polymer artificial muscle technologies are being developed that produce similar strains and higher stresses using electrostatic forces, electrostriction, ion insertion, and molecular conformational changes. Materials used include elastomers, conducting polymers, ionically conducting polymers, and carbon nanotubes. The mechanisms, performance, and remaining challenges associated with these technologies are described. Initial applications are being developed, but further work by the materials community should help make these technologies applicable in a wide range of devices where muscle-like motion is desirable.

  16. Mechanism of artificial heart

    CERN Document Server

    Yamane, Takashi

    2016-01-01

    This book first describes medical devices in relation to regenerative medicine before turning to a more specific topic: artificial heart technologies. Not only the pump mechanisms but also the bearing, motor mechanisms, and materials are described, including expert information. Design methods are described to enhance hemocompatibility: main concerns are reduction of blood cell damage and protein break, as well as prevention of blood clotting. Regulatory science from R&D to clinical trials is also discussed to verify the safety and efficacy of the devices.

  17. Uncertainty in artificial intelligence

    CERN Document Server

    Kanal, LN

    1986-01-01

    How to deal with uncertainty is a subject of much controversy in Artificial Intelligence. This volume brings together a wide range of perspectives on uncertainty, many of the contributors being the principal proponents in the controversy.Some of the notable issues which emerge from these papers revolve around an interval-based calculus of uncertainty, the Dempster-Shafer Theory, and probability as the best numeric model for uncertainty. There remain strong dissenting opinions not only about probability but even about the utility of any numeric method in this context.

  18. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2010-01-01

    Updated and expanded, Bayesian Artificial Intelligence, Second Edition provides a practical and accessible introduction to the main concepts, foundation, and applications of Bayesian networks. It focuses on both the causal discovery of networks and Bayesian inference procedures. Adopting a causal interpretation of Bayesian networks, the authors discuss the use of Bayesian networks for causal modeling. They also draw on their own applied research to illustrate various applications of the technology.New to the Second EditionNew chapter on Bayesian network classifiersNew section on object-oriente

  19. 7 CFR 51.1220 - Leaf or limb rub injury.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf or limb rub injury. 51.1220 Section 51.1220... STANDARDS) United States Standards for Grades of Peaches Definitions § 51.1220 Leaf or limb rub injury. “Leaf or limb rub injury” means that the scarring is not smooth, not light colored, or aggregates...

  20. Correcting for limb inertia and compliance in fast ergometers

    NARCIS (Netherlands)

    Hof, AL

    1997-01-01

    In fast moving ergometers for human limbs the acceleration induces transient moments due to the inertia of the limb, in combination with a not perfectly rigid limb fixation. Methods are described by which these effects can be corrected for. The correction of the moment consists of filtering the reco

  1. Artificial Intelligence in Space Platforms.

    Science.gov (United States)

    1984-12-01

    computer algorithms, there still appears to be a need for Artificial Inteligence techniques in the navigation area. The reason is that navigaion, in...RD-RI32 679 ARTIFICIAL INTELLIGENCE IN SPACE PLRTFORNSMU AIR FORCE 1/𔃼 INST OF TECH WRIGHT-PRTTERSON AFB OH SCHOOL OF ENGINEERING M A WRIGHT DEC 94...i4 Preface The purpose of this study was to analyze the feasibility of implementing Artificial Intelligence techniques to increase autonomy for

  2. Trimaran Resistance Artificial Neural Network

    Science.gov (United States)

    2011-01-01

    11th International Conference on Fast Sea Transportation FAST 2011, Honolulu, Hawaii, USA, September 2011 Trimaran Resistance Artificial Neural Network Richard...Trimaran Resistance Artificial Neural Network 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e... Artificial Neural Network and is restricted to the center and side-hull configurations tested. The value in the parametric model is that it is able to

  3. Parallel artificial liquid membrane extraction

    DEFF Research Database (Denmark)

    Gjelstad, Astrid; Rasmussen, Knut Einar; Parmer, Marthe Petrine

    2013-01-01

    This paper reports development of a new approach towards analytical liquid-liquid-liquid membrane extraction termed parallel artificial liquid membrane extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated by an arti...... by an artificial liquid membrane. Parallel artificial liquid membrane extraction is a modification of hollow-fiber liquid-phase microextraction, where the hollow fibers are replaced by flat membranes in a 96-well plate format....

  4. How to teach artificial organs.

    Science.gov (United States)

    Zapanta, Conrad M; Borovetz, Harvey S; Lysaght, Michael J; Manning, Keefe B

    2011-01-01

    Artificial organs education is often an overlooked field for many bioengineering and biomedical engineering students. The purpose of this article is to describe three different approaches to teaching artificial organs. This article can serve as a reference for those who wish to offer a similar course at their own institutions or incorporate these ideas into existing courses. Artificial organ classes typically fulfill several ABET (Accreditation Board for Engineering and Technology) criteria, including those specific to bioengineering and biomedical engineering programs.

  5. Spinal Cord Stimulation Therapy for the Treatment of Concomitant Phantom Limb Pain and Critical Limb Ischemia.

    Science.gov (United States)

    De Caridi, Giovanni; Massara, Mafalda; Serra, Raffaele; Risitano, Claudia; Giardina, Massimiliano; Acri, Ignazio Eduardo; Volpe, Pietro; David, Antonio

    2016-04-01

    Phantom limb pain (PLP) is a chronic condition experienced by about 80% of patients who have undergone amputation. In most patients, both the frequency and the intensity of pain attacks diminish with time, but severe pain persists in about 5-10%. Probably, factors in both the peripheral and central nervous system play a role in the occurrence and persistence of pain in the amputated lower limb. The classical treatment of PLP can be divided into pharmacologic, surgical, anesthetic, and psychological modalities. Spinal cord stimulation (SCS) does not represent a new method of treatment for this condition. However, the concomitant treatment of PLP and critical lower limb ischemia by using SCS therapy has not yet been described in the current literature. The aim of the present article is to highlight the possibility of apply SCS for the simultaneous treatment of PLP and critical lower limb ischemia on the contralateral lower limb after failure of medical therapy in a group of 3 patients, obtaining pain relief in both lower limbs, delaying an endovascular or surgical revascularization. After SCS implantation and test stimulation, the pain was reduced by 50% on both the right and the left side in all our patients. The main indications for permanent SCS therapy after 1 week of test stimulation were represented by transcutaneous oxygen (TcPO2) increase >75%, decrease of opioids analgesics use of at least 50% and a pain maintained to within 20-30/100 mm on visual analog scale.

  6. Experimental assessment of a new direct fixation implant for artificial limbs.

    NARCIS (Netherlands)

    Tomaszewski, P.K.; Lasnier, B.; Hannink, G.J.; Verkerke, G.J.; Verdonschot, N.J.J.

    2013-01-01

    An alternative to prosthetic socket rehabilitation of patients with transfemoral amputation is realized by means of direct skeletal fixation devices. offering significant improvements in mobility and comfort. However, strain shielding due to high stiffness of these metal-based implants causes consid

  7. Experimental assessment of a new direct fixation implant for artificial limbs

    NARCIS (Netherlands)

    Tomaszewski, P. K.; Lasnier, B.; Hannink, G.; Verkerke, G. J.; Verdonschot, N.

    2013-01-01

    An alternative to prosthetic socket rehabilitation of patients with transfemoral amputation is realized by means of direct skeletal fixation devices, offering significant improvements in mobility and comfort. However, strain shielding due to high stiffness of these metal-based implants causes consid

  8. Experimental assessment of a new direct fixation implant for artificial limbs.

    Science.gov (United States)

    Tomaszewski, P K; Lasnier, B; Hannink, G; Verkerke, G J; Verdonschot, N

    2013-05-01

    An alternative to prosthetic socket rehabilitation of patients with transfemoral amputation is realized by means of direct skeletal fixation devices. offering significant improvements in mobility and comfort. However, strain shielding due to high stiffness of these metal-based implants causes considerable and progressive bone loss. To overcome this phenomenon a new concept of a direct fixation implant, in form of a collared metallic pin articulating inside a polymer intramedullary part, was developed. In this study we used experimental and finite element techniques to assess whether the novel concept produced a more physiological strain distribution in the bone as compared to a standard titanium implant. Cortical strains were measured experimentally on seven human cadaver femora, both intact and implanted with a generic standard implant and the new implant. Three load configurations were considered, simulating: heel strike, toe off and one leg stance. A finite element model derived from computed tomography data was used to calculate strains in intact bone and bone with generic models of the two implant types. Significant strain shielding occurred around both implant types, albeit that for the novel design strain shielding was generally less (ptransfemoral amputation.

  9. Upper Extremity Artificial Limb Control as an Issue Related to Movement and Mobility in Daily Living

    Science.gov (United States)

    Wallace, Steve; Anderson, David I.; Trujillo, Michael; Weeks, Douglas L.

    2005-01-01

    The 1992 NIH Research Planning Conference on Prosthetic and Orthotic Research for the 21st Century (Childress, 1992) recognized that the field of prosthetics lacks theoretical understanding and empirical studies on learning to control an upper-extremity prosthesis. We have addressed this problem using a novel approach in which persons without…

  10. Optimal space-time precoding of artificial sensory feedback through mutichannel microstimulation in bi-directional brain-machine interfaces

    Science.gov (United States)

    Daly, John; Liu, Jianbo; Aghagolzadeh, Mehdi; Oweiss, Karim

    2012-12-01

    Brain-machine interfaces (BMIs) aim to restore lost sensorimotor and cognitive function in subjects with severe neurological deficits. In particular, lost somatosensory function may be restored by artificially evoking patterns of neural activity through microstimulation to induce perception of tactile and proprioceptive feedback to the brain about the state of the limb. Despite an early proof of concept that subjects could learn to discriminate a limited vocabulary of intracortical microstimulation (ICMS) patterns that instruct the subject about the state of the limb, the dynamics of a moving limb are unlikely to be perceived by an arbitrarily-selected, discrete set of static microstimulation patterns, raising questions about the generalization and the scalability of this approach. In this work, we propose a microstimulation protocol intended to activate optimally the ascending somatosensory pathway. The optimization is achieved through a space-time precoder that maximizes the mutual information between the sensory feedback indicating the limb state and the cortical neural response evoked by thalamic microstimulation. Using a simplified multi-input multi-output model of the thalamocortical pathway, we show that this optimal precoder can deliver information more efficiently in the presence of noise compared to suboptimal precoders that do not account for the afferent pathway structure and/or cortical states. These results are expected to enhance the way microstimulation is used to induce somatosensory perception during sensorimotor control of artificial devices or paralyzed limbs.

  11. [Artificial neural networks in Neurosciences].

    Science.gov (United States)

    Porras Chavarino, Carmen; Salinas Martínez de Lecea, José María

    2011-11-01

    This article shows that artificial neural networks are used for confirming the relationships between physiological and cognitive changes. Specifically, we explore the influence of a decrease of neurotransmitters on the behaviour of old people in recognition tasks. This artificial neural network recognizes learned patterns. When we change the threshold of activation in some units, the artificial neural network simulates the experimental results of old people in recognition tasks. However, the main contributions of this paper are the design of an artificial neural network and its operation inspired by the nervous system and the way the inputs are coded and the process of orthogonalization of patterns.

  12. Development of artificial empathy.

    Science.gov (United States)

    Asada, Minoru

    2015-01-01

    We have been advocating cognitive developmental robotics to obtain new insight into the development of human cognitive functions by utilizing synthetic and constructive approaches. Among the different emotional functions, empathy is difficult to model, but essential for robots to be social agents in our society. In my previous review on artificial empathy (Asada, 2014b), I proposed a conceptual model for empathy development beginning with emotional contagion to envy/schadenfreude along with self/other differentiation. In this article, the focus is on two aspects of this developmental process, emotional contagion in relation to motor mimicry, and cognitive/affective aspects of the empathy. It begins with a summary of the previous review (Asada, 2014b) and an introduction to affective developmental robotics as a part of cognitive developmental robotics focusing on the affective aspects. This is followed by a review and discussion on several approaches for two focused aspects of affective developmental robotics. Finally, future issues involved in the development of a more authentic form of artificial empathy are discussed.

  13. Creating an Artificial Muscle

    Science.gov (United States)

    Bohon, Katherine; Krause, Sonja

    1997-03-01

    Striated skeletal muscle responds to a nerve impulse in less than 100 ms. In the past, polymeric gels and conducting polymers have been investigated for use as artificial muscle. However, the main problem with these materials is their relatively slow response (>3 seconds). On the other hand, electrorheological (ER) fluids are materials that change from a liquid to a solid upon application of an electric field. These fluids have a response on the order of a millisecond. A novel approach to artificial muscle utilizing the fast time response of ER fluids and the elasticity of polymeric gels has been investigated. A commercial sample of a two-part poly(dimethyl siloxane) (PDMS) dielectric gel was used. The PDMS was cured around two flexible electrodes 5 mm apart while a mixture of PDMS with solvent was cured between the electrodes. The solvents were either silicone oil or an ER fluid composed of crosslinked poly(ethylene oxide) (PEO) particles in silicone oil. The mixtures investigated were 90/10, 60/40, 50/50, 40/60, 10/90 PDMS/solvent. Upon application of a 6.2 kV/cm DC electric field the gel was reversibly compressed. The time response of the gel was actuator has been created using the 60/40 PDMS/ER fluid mixture.

  14. The total artificial heart.

    Science.gov (United States)

    Cook, Jason A; Shah, Keyur B; Quader, Mohammed A; Cooke, Richard H; Kasirajan, Vigneshwar; Rao, Kris K; Smallfield, Melissa C; Tchoukina, Inna; Tang, Daniel G

    2015-12-01

    The total artificial heart (TAH) is a form of mechanical circulatory support in which the patient's native ventricles and valves are explanted and replaced by a pneumatically powered artificial heart. Currently, the TAH is approved for use in end-stage biventricular heart failure as a bridge to heart transplantation. However, with an increasing global burden of cardiovascular disease and congestive heart failure, the number of patients with end-stage heart failure awaiting heart transplantation now far exceeds the number of available hearts. As a result, the use of mechanical circulatory support, including the TAH and left ventricular assist device (LVAD), is growing exponentially. The LVAD is already widely used as destination therapy, and destination therapy for the TAH is under investigation. While most patients requiring mechanical circulatory support are effectively treated with LVADs, there is a subset of patients with concurrent right ventricular failure or major structural barriers to LVAD placement in whom TAH may be more appropriate. The history, indications, surgical implantation, post device management, outcomes, complications, and future direction of the TAH are discussed in this review.

  15. Effect of Upper Limb Deformities on Gross Motor and Upper Limb Functions in Children with Spastic Cerebral Palsy

    Science.gov (United States)

    Park, Eun Sook; Sim, Eun Geol; Rha, Dong-wook

    2011-01-01

    The aims of this study were to investigate the nature and extent of upper limb deformities via the use of various classifications, and to analyze the relationship between upper limb deformities and gross motor or upper limb functionality levels. Upper extremity data were collected from 234 children with spastic cerebral palsy (CP) who were…

  16. Generative Artificial Intelligence : Philosophy and Theory of Artificial Intelligence

    NARCIS (Netherlands)

    van der Zant, Tijn; Kouw, Matthijs; Schomaker, Lambertus; Mueller, Vincent C.

    2013-01-01

    The closed systems of contemporary Artificial Intelligence do not seem to lead to intelligent machines in the near future. What is needed are open-ended systems with non-linear properties in order to create interesting properties for the scaffolding of an artificial mind. Using post-structuralistic

  17. Clustering-based limb identification for pressure ulcer risk assessment.

    Science.gov (United States)

    Baran Pouyan, M; Nourani, M; Pompeo, M

    2015-01-01

    Bedridden patients have a high risk of developing pressure ulcers. Risk assessment for pressure ulceration is critical for preventive care. For a reliable assessment, we need to identify and track the limbs continuously and accurately. In this paper, we propose a method to identify body limbs using a pressure mat. Three prevalent sleep postures (supine, left and right postures) are considered. Then, predefined number of limbs (body parts) are identified by applying Fuzzy C-Means (FCM) clustering on key attributes. We collected data from 10 adult subjects and achieved average accuracy of 93.2% for 10 limbs in supine and 7 limbs in left/right postures.

  18. Reduction of residual limb volume in people with transtibial amputation

    Directory of Open Access Journals (Sweden)

    Audrey T. Tantua, MD

    2014-11-01

    Full Text Available The early postoperative phase after transtibial amputation is characterized by rapid residual limb volume reduction. Accurate measurement of residual limb volume is important for the timing of fitting a prosthesis. The aim of this study was to analyze the reduction of residual limb volume in people with transtibial amputation and to correlate residual limb volume with residual limb circumference. In a longitudinal cohort study of 21 people who had a transtibial amputation, residual limb volume was measured using a laser scanner and circumference was measured using a tape measure 1 wk postamputation and every 3 wk thereafter until 24 wk postamputation. A linear mixed model analysis was performed with weeks postamputation transformed according to the natural logarithm as predictor. Residual limb volume decreased significantly over time, with a large variation between patients. Residual limb volume did not correlate well with circumference. On average, residual limb volume decreased 200.5 mL (9.7% of the initial volume per natural logarithm of the weeks postamputation. The decrease in residual limb volume following a transtibial amputation was substantial in the early postamputation phase, followed by a leveling off. It was not possible to determine the specific moment at which the residual limb volume stabilized.

  19. Residual limb volume change: Systematic review of measurement and management

    Directory of Open Access Journals (Sweden)

    Joan E. Sanders, PhD

    2011-10-01

    Full Text Available Management of residual limb volume affects decisions regarding timing of fit of the first prosthesis, when a new prosthetic socket is needed, design of a prosthetic socket, and prescription of accommodation strategies for daily volume fluctuations. This systematic review assesses what is known about measurement and management of residual limb volume change in persons with lower-limb amputation. Publications that met inclusion criteria were grouped into three categories: group I: descriptions of residual limb volume measurement techniques; group II: studies investigating the effect of residual limb volume change on clinical care in people with lower-limb amputation; and group III: studies of residual limb volume management techniques or descriptions of techniques for accommodating or controlling residual limb volume. We found that many techniques for the measurement of residual limb volume have been described but clinical use is limited largely because current techniques lack adequate resolution and in-socket measurement capability. Overall, limited evidence exists regarding the management of residual limb volume, and the evidence available focuses primarily on adults with transtibial amputation in the early postoperative phase. While we can draw some insights from the available research about residual limb volume measurement and management, further research is required.

  20. Artificial Diets for Mosquitoes

    Directory of Open Access Journals (Sweden)

    Kristina K. Gonzales

    2016-12-01

    Full Text Available Mosquito-borne diseases are responsible for more than a million human deaths every year. Modern mosquito control strategies such as sterile insect technique (SIT, release of insects carrying a dominant lethal (RIDL, population replacement strategies (PR, and Wolbachia-based strategies require the rearing of large numbers of mosquitoes in culture for continuous release over an extended period of time. Anautogenous mosquitoes require essential nutrients for egg production, which they obtain through the acquisition and digestion of a protein-rich blood meal. Therefore, mosquito mass production in laboratories and other facilities relies on vertebrate blood from live animal hosts. However, vertebrate blood is expensive to acquire and hard to store for longer times especially under field conditions. This review discusses older and recent studies that were aimed at the development of artificial diets for mosquitoes in order to replace vertebrate blood.

  1. Artificial Immune Systems (2010)

    CERN Document Server

    Greensmith, Julie; Aickelin, Uwe

    2010-01-01

    The human immune system has numerous properties that make it ripe for exploitation in the computational domain, such as robustness and fault tolerance, and many different algorithms, collectively termed Artificial Immune Systems (AIS), have been inspired by it. Two generations of AIS are currently in use, with the first generation relying on simplified immune models and the second generation utilising interdisciplinary collaboration to develop a deeper understanding of the immune system and hence produce more complex models. Both generations of algorithms have been successfully applied to a variety of problems, including anomaly detection, pattern recognition, optimisation and robotics. In this chapter an overview of AIS is presented, its evolution is discussed, and it is shown that the diversification of the field is linked to the diversity of the immune system itself, leading to a number of algorithms as opposed to one archetypal system. Two case studies are also presented to help provide insight into the m...

  2. Sucrose compared with artificial sweeteners

    DEFF Research Database (Denmark)

    Sørensen, Lone Brinkmann; Vasilaras, Tatjana H; Astrup, Arne;

    2014-01-01

    There is a lack of appetite studies in free-living subjects supplying the habitual diet with either sucrose or artificially sweetened beverages and foods. Furthermore, the focus of artificial sweeteners has only been on the energy intake (EI) side of the energy-balance equation. The data are from...

  3. Instructional Applications of Artificial Intelligence.

    Science.gov (United States)

    Halff, Henry M.

    1986-01-01

    Surveys artificial intelligence and the development of computer-based tutors and speculates on the future of artificial intelligence in education. Includes discussion of the definitions of knowledge, expert systems (computer systems that solve tough technical problems), intelligent tutoring systems (ITS), and specific ITSs such as GUIDON, MYCIN,…

  4. A Primer on Artificial Intelligence.

    Science.gov (United States)

    Leal, Ralph A.

    A survey of literature on recent advances in the field of artificial intelligence provides a comprehensive introduction to this field for the non-technical reader. Important areas covered are: (1) definitions, (2) the brain and thinking, (3) heuristic search, and (4) programing languages used in the research of artificial intelligence. Some…

  5. Generalized Adaptive Artificial Neural Networks

    Science.gov (United States)

    Tawel, Raoul

    1993-01-01

    Mathematical model of supervised learning by artificial neural network provides for simultaneous adjustments of both temperatures of neurons and synaptic weights, and includes feedback as well as feedforward synaptic connections. Extension of mathematical model described in "Adaptive Neurons For Artificial Neural Networks" (NPO-17803). Dynamics of neural network represented in new model by less-restrictive continuous formalism.

  6. Artificial Ligaments: Promise or Panacea?

    Science.gov (United States)

    Lubell, Adele

    1987-01-01

    The Food and Drug Administration has approved a prosthetic ligament for limited use in persons with damaged anterior cruciate ligaments (ACL). This article addresses ligament repair, ACL tears, current treatment, development of the Gore-Tex artificial ligament, other artificial ligaments in process, and arguments for and against their use.…

  7. Development of a neural network screening aid for diagnosing lower limb peripheral vascular disease from photoelectric plethysmography pulse waveforms.

    Science.gov (United States)

    Allen, J; Murray, A

    1993-02-01

    An artificial neural network (ANN) was trained to classify photoelectric plethysmographic (PPG) pulse waveforms for the diagnosis of lower limb peripheral vascular disease (PVD). PPG pulses from the lower limbs, and pre- and post-exercise Doppler ultrasound ankle to brachial systolic blood pressure ratio measurements were obtained from patients referred to a vascular investigation laboratory. A single PPG pulse from the big toe of each leg was processed and normalized, and used as input data to the ANN. The ANN outputs represented the diagnostic classifications (normal, significant PVD and major PVD) and the ANN was trained with the ankle to brachial pressure indices (ABPI). The ANN structure consisted of an input layer (50 neuron units from the PPG pulse input), a single hidden layer (15 neurons) and an output layer (3 neurons for the PVD diagnoses). The back-propagation learning algorithm was used to train the ANN for 500 epochs with a PPG training set of pulses from 100 legs. Test data for network assessment comprised pulses from a further 50 legs (20 normal and 30 PVD, of which 15 were categorized as having major disease). A network sensitivity of 93% and specificity of 85% was achieved with respect to the Doppler ABPI standard, giving a diagnostic accuracy of 90%. The results of this study indicate that a neural network can be trained to distinguish between PPG pulses from normal and diseased lower limb arteries. The simplicity of PPG measurement and neural network classification holds promise for the screening of lower limb arterial PVD.

  8. Lower-Limb Rehabilitation Robot Design

    Science.gov (United States)

    Bouhabba, E. M.; Shafie, A. A.; Khan, M. R.; Ariffin, K.

    2013-12-01

    It is a general assumption that robotics will play an important role in therapy activities within rehabilitation treatment. In the last decade, the interest in the field has grown exponentially mainly due to the initial success of the early systems and the growing demand caused by increasing numbers of stroke patients and their associate rehabilitation costs. As a result, robot therapy systems have been developed worldwide for training of both the upper and lower extremities. This paper investigates and proposes a lower-limb rehabilitation robot that is used to help patients with lower-limb paralysis to improve and resume physical functions. The proposed rehabilitation robot features three rotary joints forced by electric motors providing linear motions. The paper covers mechanism design and optimization, kinematics analysis, trajectory planning, wearable sensors, and the control system design. The design and control system demonstrate that the proposed rehabilitation robot is safe and reliable with the effective design and better kinematic performance.

  9. Soft computing in artificial intelligence

    CERN Document Server

    Matson, Eric

    2014-01-01

    This book explores the concept of artificial intelligence based on knowledge-based algorithms. Given the current hardware and software technologies and artificial intelligence theories, we can think of how efficient to provide a solution, how best to implement a model and how successful to achieve it. This edition provides readers with the most recent progress and novel solutions in artificial intelligence. This book aims at presenting the research results and solutions of applications in relevance with artificial intelligence technologies. We propose to researchers and practitioners some methods to advance the intelligent systems and apply artificial intelligence to specific or general purpose. This book consists of 13 contributions that feature fuzzy (r, s)-minimal pre- and β-open sets, handling big coocurrence matrices, Xie-Beni-type fuzzy cluster validation, fuzzy c-regression models, combination of genetic algorithm and ant colony optimization, building expert system, fuzzy logic and neural network, ind...

  10. Beyond AI: Artificial Dreams Conference

    CERN Document Server

    Zackova, Eva; Kelemen, Jozef; Beyond Artificial Intelligence : The Disappearing Human-Machine Divide

    2015-01-01

    This book is an edited collection of chapters based on the papers presented at the conference “Beyond AI: Artificial Dreams” held in Pilsen in November 2012. The aim of the conference was to question deep-rooted ideas of artificial intelligence and cast critical reflection on methods standing at its foundations.  Artificial Dreams epitomize our controversial quest for non-biological intelligence, and therefore the contributors of this book tried to fully exploit such a controversy in their respective chapters, which resulted in an interdisciplinary dialogue between experts from engineering, natural sciences and humanities.   While pursuing the Artificial Dreams, it has become clear that it is still more and more difficult to draw a clear divide between human and machine. And therefore this book tries to portrait such an image of what lies beyond artificial intelligence: we can see the disappearing human-machine divide, a very important phenomenon of nowadays technological society, the phenomenon which i...

  11. Proximal monomelic amyotrophy of the upper limb.

    Science.gov (United States)

    Amir, D; Magora, A; Vatine, J J

    1987-07-01

    A 30-year-old patient of Central European origin, suffering from monomelic amyotrophy, is presented. The disease was characterized by proximal weakness of one upper limb, mainly of the shoulder girdle, accompanied by atrophy. The electrodiagnostic examination revealed signs of partial denervation in the presence of normal motor and sensory conduction. The disease, which is probably of the anterior horn cells, had a benign course and good prognosis, as evident from repeated examinations during a follow-up of eight years.

  12. Endovascular Management of Acute Limb Ischemia.

    LENUS (Irish Health Repository)

    Hynes, Brian G

    2011-09-14

    Despite major advances in pharmacologic and endovascular therapies, acute limb ischemia (ALI) continues to result in significant morbidity and mortality. The incidence of ALI may be as high as 13-17 cases per 100,000 people per year, with mortality rates approaching 18% in some series. This review will address the contemporary endovascular management of ALI encompassing pharmacologic and percutaneous interventional treatment strategies.

  13. Advances in lower-limb prosthetic technology.

    Science.gov (United States)

    Laferrier, Justin Z; Gailey, Robert

    2010-02-01

    The boundaries once faced by individuals with amputations are quickly being overcome through biotechnology. Although there are currently no prosthetics capable of replicating anatomic function, there have been radical advancements in prosthetic technology, medical science, and rehabilitation in the past 30 years, vastly improving functional mobility and quality of life for individuals with lower-limb amputations. What once seemed impossible is rapidly becoming reality. The future seems limitless, and the replication of anatomic function now seems possible.

  14. Special Considerations for Multiple Limb Amputation

    OpenAIRE

    Pasquina, Paul F.; Miller, Matthew; CARVALHO, A. J. de; Corcoran, Michael; Vandersea, James; Johnson, Elizabeth; Chen, Yin-Ting

    2014-01-01

    It has been estimated that more than 1.6 million individuals in the United States have undergone at least one amputation. The literature abounds with research of the classifications of such injuries, their etiologies, epidemiologies, treatment regimens, average age of onset (average age of amputation), and much more. The subpopulation that is often overlooked in these evaluations, however, is comprised of individuals who have suffered multiple limb loss. The challenges faced by those with sin...

  15. GOMOS bright limb ozone data set

    Directory of Open Access Journals (Sweden)

    S. Tukiainen

    2015-01-01

    Full Text Available We have created a daytime ozone profile data set from the measurements of the Global Ozone Monitoring by Occultation of Stars (GOMOS instrument on board the Envisat satellite. This so-called GOMOS bright limb (GBL data set contains ~ 358 000 stratospheric daytime ozone profiles measured by GOMOS in 2002–2012. The GBL data set complements the widely used GOMOS night-time data based on stellar occultation measurements. The GBL data set is based on the GOMOS daytime occultations but instead of the transmitted star light, we use limb scattered solar light. The ozone profiles retrieved from these radiance spectra cover 18–60 km tangent height range and have approximately 2–3 km vertical resolution. We show that these profiles are generally in better than 10% agreement with the NDACC (Network for the Detection of Atmospheric Composition Change ozone sounding profiles and with the GOMOS night-time, MLS (Microwave Limb Sounder, and OSIRIS (Optical Spectrograph, and InfraRed Imaging System satellite measurements. However, there is a 10–13% negative bias at 40 km tangent height and a 10–50% positive bias at 50 km when the solar zenith angle > 75°. These biases are most likely caused by stray light which is difficult to characterize and remove entirely from the measured spectra. Nevertheless, the GBL data set approximately doubles the amount of useful GOMOS ozone profiles and improves coverage of the summer pole.

  16. Lymphoscintigraphic evaluation of chronic lower limb oedema.

    Science.gov (United States)

    Khan, O; Maharaj, P; Rampaul, R; Archibald, A; Naipaul, R; Loutan, N

    2003-06-01

    Ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), venography, lymphoscinti-graphy (LS) and contrast lymphography are frequently utilized in the evaluation of lower limb oedema but no clinical data from the Caribbean have been published on the role of LS despite its well-recognized clinical application. The successful clinical application of CT, colour doppler sonography and MRI in differentiating the various causes of lower limb oedema is well understood. Lymphoscintigraphy has found less acceptability especially in the Caribbean where nuclear imaging techniques are only now currently being developed. This paper describes the initial experience with this technique in 15 patients over a five-year period and discusses its value when lower limb lymphoedema is suspected. Scintigrams were analyzed for visualization of lymph vessels and lymph nodes, dilatation of lymphatic vessels, collaterals and dermal back flow. Lymphoscintigrams were classified as normal (n = 5) or consistent with lymphoedema (n = 10). Failure to visualize lymphatic vessels occurred in two cases of suspected primary lymphoedema. In the remaining eight cases of secondary lymphoedema, a positive study based on altered lymphatic flow and anatomy was recorded. An alternative explanation was offered in three out of five cases in which a normal lymphoscintigram was obtained.

  17. What Is a Total Artificial Heart?

    Science.gov (United States)

    ... the NHLBI on Twitter. What Is a Total Artificial Heart? A total artificial heart (TAH) is a device ... outside power source. Normal Heart and CardioWest Total Artificial Heart Figure A shows the normal structure and location ...

  18. The artificial leaf.

    Science.gov (United States)

    Nocera, Daniel G

    2012-05-15

    To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially separated electron-hole pairs. The holes of this wireless current are captured by the oxygen evolving complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin-NADP(+) reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole fuel-forming water-splitting reaction under benign conditions and under 1 sun (100 mW/cm(2)) illumination. This Account describes the construction of an artificial leaf comprising earth-abundant elements by interfacing a triple junction, amorphous silicon photovoltaic with hydrogen- and oxygen-evolving catalysts made from a ternary alloy (NiMoZn) and a cobalt-phosphate cluster (Co-OEC), respectively. The latter captures the structural and functional attributes of the PSII-OEC. Similar to the PSII-OEC, the Co-OEC self-assembles upon oxidation of an earth-abundant metal ion from 2+ to 3+, may operate in natural water at room temperature, and is self-healing. The Co-OEC also activates H(2)O by a proton-coupled electron transfer mechanism in which the Co-OEC is increased by four hole equivalents akin to the S-state pumping of the Kok cycle of PSII. X-ray absorption spectroscopy studies have established that the Co-OEC is a structural relative of Mn(3)CaO(4)-Mn cubane of the PSII-OEC, where Co replaces Mn and the cubane is extended in a

  19. [Research and development of artificial retina material].

    Science.gov (United States)

    Hu, Ning; Yang, Jun; Peng, Chenglin; Wang, Xing; Zhang, Sijie; Zhang, Ying; Zheng, Erxin

    2008-04-01

    The application of artificial retina was introduced. The principal characteristics of artificial retina material were reviewed in particular. Moreover, the recent research development and application prospect were discussed.

  20. Initiation of limb regeneration: the critical steps for regenerative capacity.

    Science.gov (United States)

    Yokoyama, Hitoshi

    2008-01-01

    While urodele amphibians (newts and salamanders) can regenerate limbs as adults, other tetrapods (reptiles, birds and mammals) cannot and just undergo wound healing. In adult mammals such as mice and humans, the wound heals and a scar is formed after injury, while wound healing is completed without scarring in an embryonic mouse. Completion of regeneration and wound healing takes a long time in regenerative and non-regenerative limbs, respectively. However, it is the early steps that are critical for determining the extent of regenerative response after limb amputation, ranging from wound healing with scar formation, scar-free wound healing, hypomorphic limb regeneration to complete limb regeneration. In addition to the accumulation of information on gene expression during limb regeneration, functional analysis of signaling molecules has recently shown important roles of fibroblast growth factor (FGF), Wnt/beta-catenin and bone morphogenic protein (BMP)/Msx signaling. Here, the routine steps of wound healing/limb regeneration and signaling molecules specifically involved in limb regeneration are summarized. Regeneration of embryonic mouse digit tips and anuran amphibian (Xenopus) limbs shows intermediate regenerative responses between the two extremes, those of adult mammals (least regenerative) and urodele amphibians (more regenerative), providing a range of models to study the various abilities of limbs to regenerate.

  1. natural or artificial diets

    Directory of Open Access Journals (Sweden)

    A. O. Meyer-Willerer

    2005-01-01

    Full Text Available Se probaron alimentos artificiales y naturales con larva de camarón (Litopenaeus vannamei cultivados en diferentes recipientes. Estos fueron ocho frascos cónicos con 15L, ocho acuarios con 50L y como grupo control, seis tanques de fibra de vidrio con 1500L; todos con agua marina fresca y filtrada. La densidad inicial en todos los recipientes fue de 70 nauplios/L. Aquellos en frascos y acuarios recibieron ya sea dieta natural o artificial. El grupo control fue cultivado con dieta natural en los tanques grandes que utilizan los laboratorios para la producción masiva de postlarvas. El principal producto de excreción de larva de camarón es el ión amonio, que es tóxico cuando está presente en concentraciones elevadas. Se determinó diariamente con el método colorimétrico del indofenol. Los resultados muestran diferencias en la concentración del ión amonio y en la sobrevivencia de larvas entre las diferentes dietas y también entre los diferentes recipientes. En aquellos con volúmenes pequeños comparados con los grandes, se presentó mayor concentración de amonio (500 a 750µg/L, en aquellos con dietas naturales, debido a que este ión sirve de fertilizante a las algas adicionadas, necesitando efectuar recambios diarios de agua posteriores al noveno día de cultivo para mantener este ión a una concentración subletal. Se obtuvo una baja cosecha de postlarvas (menor a 15% con el alimento artificial larvario, debido a la presencia de protozoarios, alimentándose con el producto comercial precipitado en el fondo de los frascos o acuarios. Los acuarios con larvas alimentadas con dieta natural también mostraron concentraciones subletales de amonio al noveno día; sin embargo, la sobrevivencia fue cuatro veces mayor que con dietas artificiales. Los tanques control con dietas naturales presentaron tasas de sobrevivencia (70 ± 5% similares a la reportada por otros laboratorios.

  2. Functional, psychosocial and professional outcomes in long-term survivors of lower-extremity osteosarcomas: amputation versus limb salvage.

    Science.gov (United States)

    Ottaviani, Giulia; Robert, Rhonda S; Huh, Winston W; Jaffe, Norman

    2009-01-01

    As the number of osteosarcoma survivors increases, the impact of quality of life and function needs to be addressed. Limb salvage is the preferred treatment when patients have treatment options; yet, the questionable long-term durability and complications of prostheses, combined with ambiguous function, leave some doubt regarding the best clinical and surgical options. Comparisons between limb salvage patients, amputees and controls also require further investigation. Amputation would leave the patients with a lifelong requirement for an external prosthetic leg associated with an overall limited walking distance. While artificial limbs are much more sophisticated than those used in the past, phantom limb sensations remain a substantial and unpredictable problem in the amputee. Complications such as stump overgrowth, bleeding, and infection, also require further elucidation. Limb salvage surgery using endoprosthesis, allografts or reconstruction is performed in approximately 85% of patients affected by osteosarcoma located in the middle and/or distal femur. One drawback in limb-salvage surgery in the long-term survivor is that endoprostheses have a limited life span with long-term prosthetic failure. The inherent high rate of reoperation remains a serious problem. Replacing a damaged, infected or severely worn-out arthroplastic joint or its intramedullary stem is difficult, especially in the long-stem cemented endoprostheses used in the 1980s. Limb lengthening procedures in patients who have not reached maturity must also be addressed. Periprosthetic infections, compared to other indications for joint reconstruction, were found to be more frequent in patients treated for neoplastic conditions and their outcome can be devastating, resulting in total loss of joint function, amputation, and systemic complications. Quality of life in terms of function, psychological outcome and endpoint achievements such as marriage and employment apparently do not differ significantly

  3. Artificial Neural Network Analysis System

    Science.gov (United States)

    2007-11-02

    Contract No. DASG60-00-M-0201 Purchase request no.: Foot in the Door-01 Title Name: Artificial Neural Network Analysis System Company: Atlantic... Artificial Neural Network Analysis System 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Powell, Bruce C 5d. PROJECT NUMBER 5e. TASK NUMBER...34) 27-02-2001 Report Type N/A Dates Covered (from... to) ("DD MON YYYY") 28-10-2000 27-02-2001 Title and Subtitle Artificial Neural Network Analysis

  4. Bioengineering of Artificial Lymphoid Organs.

    Science.gov (United States)

    Nosenko, M A; Drutskaya, M S; Moisenovich, M M; Nedospasov, S A

    2016-01-01

    This review addresses the issue of bioengineering of artificial lymphoid organs.Progress in this field may help to better understand the nature of the structure-function relations that exist in immune organs. Artifical lymphoid organs may also be advantageous in the therapy or correction of immunodefficiencies, autoimmune diseases, and cancer. The structural organization, development, and function of lymphoid tissue are analyzed with a focus on the role of intercellular contacts and on the cytokine signaling pathways regulating these processes. We describe various polymeric materials, as scaffolds, for artificial tissue engineering. Finally, published studies in which artificial lymphoid organs were generated are reviewed and possible future directions in the field are discussed.

  5. Artificial intelligence in medicine.

    Science.gov (United States)

    Hamet, Pavel; Tremblay, Johanne

    2017-04-01

    Artificial Intelligence (AI) is a general term that implies the use of a computer to model intelligent behavior with minimal human intervention. AI is generally accepted as having started with the invention of robots. The term derives from the Czech word robota, meaning biosynthetic machines used as forced labor. In this field, Leonardo Da Vinci's lasting heritage is today's burgeoning use of robotic-assisted surgery, named after him, for complex urologic and gynecologic procedures. Da Vinci's sketchbooks of robots helped set the stage for this innovation. AI, described as the science and engineering of making intelligent machines, was officially born in 1956. The term is applicable to a broad range of items in medicine such as robotics, medical diagnosis, medical statistics, and human biology-up to and including today's "omics". AI in medicine, which is the focus of this review, has two main branches: virtual and physical. The virtual branch includes informatics approaches from deep learning information management to control of health management systems, including electronic health records, and active guidance of physicians in their treatment decisions. The physical branch is best represented by robots used to assist the elderly patient or the attending surgeon. Also embodied in this branch are targeted nanorobots, a unique new drug delivery system. The societal and ethical complexities of these applications require further reflection, proof of their medical utility, economic value, and development of interdisciplinary strategies for their wider application.

  6. Artificial Immune Systems Tutorial

    CERN Document Server

    Aickelin, Uwe

    2008-01-01

    The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted an...

  7. Artificial Immune Systems

    CERN Document Server

    Aickelin, Uwe

    2009-01-01

    The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted an...

  8. Programmable artificial phototactic microswimmer

    Science.gov (United States)

    Dai, Baohu; Wang, Jizhuang; Xiong, Ze; Zhan, Xiaojun; Dai, Wei; Li, Chien-Cheng; Feng, Shien-Ping; Tang, Jinyao

    2016-12-01

    Phototaxis is commonly observed in motile photosynthetic microorganisms. For example, green algae are capable of swimming towards a light source (positive phototaxis) to receive more energy for photosynthesis, or away from a light source (negative phototaxis) to avoid radiation damage or to hide from predators. Recently, with the aim of applying nanoscale machinery to biomedical applications, various inorganic nanomotors based on different propulsion mechanisms have been demonstrated. The only method to control the direction of motion of these self-propelled micro/nanomotors is to incorporate a ferromagnetic material into their structure and use an external magnetic field for steering. Here, we show an artificial microswimmer that can sense and orient to the illumination direction of an external light source. Our microswimmer is a Janus nanotree containing a nanostructured photocathode and photoanode at opposite ends that release cations and anions, respectively, propelling the microswimmer by self-electrophoresis. Using chemical modifications, we can control the zeta potential of the photoanode and program the microswimmer to exhibit either positive or negative phototaxis. Finally, we show that a school of microswimmers mimics the collective phototactic behaviour of green algae in solution.

  9. Progressive specification rather than intercalation of segments during limb regeneration.

    Science.gov (United States)

    Roensch, Kathleen; Tazaki, Akira; Chara, Osvaldo; Tanaka, Elly M

    2013-12-13

    An amputated salamander limb regenerates the correct number of segments. Models explaining limb regeneration were largely distinct from those for limb development, despite the presence of common patterning molecules. Intercalation has been an important concept to explain salamander limb regeneration, but clear evidence supporting or refuting this model was lacking. In the intercalation model, the first blastema cells acquire fingertip identity, creating a gap in positional identity that triggers regeneration of the intervening region from the stump. We used HOXA protein analysis and transplantation assays to show that axolotl limb blastema cells acquire positional identity in a proximal-to-distal sequence. Therefore, intercalation is not the primary mechanism for segment formation during limb regeneration in this animal. Patterning in development and regeneration uses similar mechanisms.

  10. Artificial intelligence: Deep neural reasoning

    Science.gov (United States)

    Jaeger, Herbert

    2016-10-01

    The human brain can solve highly abstract reasoning problems using a neural network that is entirely physical. The underlying mechanisms are only partially understood, but an artificial network provides valuable insight. See Article p.471

  11. Darwin, artificial selection, and poverty.

    Science.gov (United States)

    Sanchez, Luis

    2010-03-01

    This paper argues that the processes of evolutionary selection are becoming increasingly artificial, a trend that goes against the belief in a purely natural selection process claimed by Darwin's natural selection theory. Artificial selection is mentioned by Darwin, but it was ignored by Social Darwinists, and it is all but absent in neo-Darwinian thinking. This omission results in an underestimation of probable impacts of artificial selection upon assumed evolutionary processes, and has implications for the ideological uses of Darwin's language, particularly in relation to poverty and other social inequalities. The influence of artificial selection on genotypic and phenotypic adaptations arguably represents a substantial shift in the presumed path of evolution, a shift laden with both biological and political implications.

  12. Artificial Intelligence in Civil Engineering

    Directory of Open Access Journals (Sweden)

    Pengzhen Lu

    2012-01-01

    Full Text Available Artificial intelligence is a branch of computer science, involved in the research, design, and application of intelligent computer. Traditional methods for modeling and optimizing complex structure systems require huge amounts of computing resources, and artificial-intelligence-based solutions can often provide valuable alternatives for efficiently solving problems in the civil engineering. This paper summarizes recently developed methods and theories in the developing direction for applications of artificial intelligence in civil engineering, including evolutionary computation, neural networks, fuzzy systems, expert system, reasoning, classification, and learning, as well as others like chaos theory, cuckoo search, firefly algorithm, knowledge-based engineering, and simulated annealing. The main research trends are also pointed out in the end. The paper provides an overview of the advances of artificial intelligence applied in civil engineering.

  13. Food analysis using artificial senses.

    Science.gov (United States)

    Śliwińska, Magdalena; Wiśniewska, Paulina; Dymerski, Tomasz; Namieśnik, Jacek; Wardencki, Waldemar

    2014-02-19

    Nowadays, consumers are paying great attention to the characteristics of food such as smell, taste, and appearance. This motivates scientists to imitate human senses using devices known as electronic senses. These include electronic noses, electronic tongues, and computer vision. Thanks to the utilization of various sensors and methods of signal analysis, artificial senses are widely applied in food analysis for process monitoring and determining the quality and authenticity of foods. This paper summarizes achievements in the field of artificial senses. It includes a brief history of these systems, descriptions of most commonly used sensors (conductometric, potentiometric, amperometic/voltammetric, impedimetric, colorimetric, piezoelectric), data analysis methods (for example, artificial neural network (ANN), principal component analysis (PCA), model CIE L*a*b*), and application of artificial senses to food analysis, in particular quality control, authenticity and falsification assessment, and monitoring of production processes.

  14. 100 top-cited scientific papers in limb prosthetics

    OpenAIRE

    Eshraghi, Arezoo; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq; Shadgan, Babak

    2013-01-01

    Research has tremendously contributed to the developments in both practical and fundamental aspects of limb prosthetics. These advancements are reflected in scientific articles, particularly in the most cited papers. This article aimed to identify the 100 top-cited articles in the field of limb prosthetics and to investigate their main characteristics. Articles related to the field of limb prosthetics and published in the Web of Knowledge database of the Institute for Scientific Information (...

  15. Compressive neuropathy in the upper limb

    Directory of Open Access Journals (Sweden)

    Mukund R Thatte

    2011-01-01

    Full Text Available Entrampment neuropathy or compression neuropathy is a fairly common problem in the upper limb. Carpal tunnel syndrome is the commonest, followed by Cubital tunnel compression or Ulnar Neuropathy at Elbow. There are rarer entities like supinator syndrome and pronator syndrome affecting the Radial and Median nerves respectively. This article seeks to review comprehensively the pathophysiology, Anatomy and treatment of these conditions in a way that is intended for the practicing Hand Surgeon as well as postgraduates in training. It is generally a rewarding exercise to treat these conditions because they generally do well after corrective surgery. Diagnostic guidelines, treatment protocols and surgical technique has been discussed.

  16. UPPER LIMB PROSTHETIC FOR STROKE AFFECTED PATIENTS

    Directory of Open Access Journals (Sweden)

    DEBIKA KHANRA,

    2011-04-01

    Full Text Available Paralysis causes loss of muscle function and loss of feeling in the affected area. The main problem faced by the patients after paralysis is muscle atrophy caused due to non-functionality of the stump. Orthotics is an orthopedic device which supports the function of the arm, leg or torso. This paper deals with the design of an upper limb orthotic device which has a hollow shell/ braces structure and can be used by paralyzed patients to bring about simple hand movements independently by the patient.

  17. Mechanical properties of artificial snow

    OpenAIRE

    Lintzén, Nina

    2013-01-01

    Mechanical properties of snow have been a subject of research since the mid-20th century. Theresearch done is based on natural snow. During the last decades the winter business industryhas been growing and also the interest for constructing buildings and artwork of snow. Suchconstructions are generally built using artificial snow, i.e. snow produced by snow guns. Up tothe present constructions of snow are designed based on knowledge by experience. Only minorscientific studies on artificial sn...

  18. What are artificial neural networks?

    DEFF Research Database (Denmark)

    Krogh, Anders

    2008-01-01

    Artificial neural networks have been applied to problems ranging from speech recognition to prediction of protein secondary structure, classification of cancers and gene prediction. How do they work and what might they be good for? Udgivelsesdato: 2008-Feb......Artificial neural networks have been applied to problems ranging from speech recognition to prediction of protein secondary structure, classification of cancers and gene prediction. How do they work and what might they be good for? Udgivelsesdato: 2008-Feb...

  19. The handbook of artificial intelligence

    CERN Document Server

    Barr, Avron

    1982-01-01

    The Handbook of Artificial Intelligence, Volume II focuses on the improvements in artificial intelligence (AI) and its increasing applications, including programming languages, intelligent CAI systems, and the employment of AI in medicine, science, and education. The book first elaborates on programming languages for AI research and applications-oriented AI research. Discussions cover scientific applications, teiresias, applications in chemistry, dependencies and assumptions, AI programming-language features, and LISP. The manuscript then examines applications-oriented AI research in medicine

  20. Medical applications of artificial intelligence

    CERN Document Server

    Agah, Arvin

    2013-01-01

    Enhanced, more reliable, and better understood than in the past, artificial intelligence (AI) systems can make providing healthcare more accurate, affordable, accessible, consistent, and efficient. However, AI technologies have not been as well integrated into medicine as predicted. In order to succeed, medical and computational scientists must develop hybrid systems that can effectively and efficiently integrate the experience of medical care professionals with capabilities of AI systems. After providing a general overview of artificial intelligence concepts, tools, and techniques, Medical Ap

  1. Artificial weathering of granite

    Directory of Open Access Journals (Sweden)

    Silva Hermo, B.

    2008-06-01

    Full Text Available This article summarizes a series of artificial weathering tests run on granite designed to: simulate the action of weathering agents on buildings and identify the underlying mechanisms, determine the salt resistance of different types of rock; evaluate consolidation and water-repellent treatment durability; and confirm hypotheses about the origin of salts such as gypsum that are often found in granite buildings. Salt crystallization tests were also conducted, using sodium chloride, sodium sulphate, calcium sulphate and seawater solutions. One of these tests was conducted in a chamber specifically designed to simulate salt spray weathering and another in an SO2 chamber to ascertain whether granite is subject to sulphation. The test results are analyzed and discussed, along with the shortcomings of each type of trial as a method for simulating the decay observed in monuments. The effect of factors such as wet-dry conditions, type of saline solution and the position of the planes of weakness on the type of decay is also addressed.En este trabajo se hace una síntesis de varios ensayos de alteración artificial realizados con rocas graníticas. Estos ensayos tenían distintos objetivos: reproducir las formas de alteración encontradas en los edificios para llegar a conocer los mecanismos que las generan, determinar la resistencia de las diferentes rocas a la acción de las sales, evaluar la durabilidad de tratamientos de consolidación e hidrofugación y constatar hipótesis acerca del origen de algunas sales, como el yeso, que aparecen frecuentemente en edificios graníticos. En los ensayos de cristalización de sales se utilizaron disoluciones de cloruro de sodio, sulfato de sodio, sulfato de calcio y agua de mar. Uno de estos ensayos se llevó a cabo en una cámara especialmente diseñada para reproducir la alteración por aerosol marino y otro se realizó en una cámara de SO2, con el objeto de comprobar si en rocas graníticas se puede producir

  2. Inter-limb differences in quadriceps strength and volitional activation.

    Science.gov (United States)

    Pietrosimone, Brian G; Park, Chang M; Gribble, Phillip A; Pfile, Kate R; Tevald, Michael A

    2012-01-01

    In this crossover study, we wished to determine if normalized inter-limb differences in strength differed from inter-limb differences in voluntary activation at 30°, 70°, and 90° of knee flexion. We also assessed the relationship between inter-limb differences in torque with the inter-limb differences in activation. Twenty-five healthy volunteers were used for final data analyses; the order of leg tested, joint angle, and measurement technique (isokinetic strength, voluntary activation) were randomly assigned. Quadriceps strength was measured isokinetically at 1.05 rad · s(-1), while quadriceps voluntary activation was assessed via the central activation ratio. Absolute values of inter-limb differences for both measures were calculated by subtracting the non-dominant leg values from those of the dominant leg. Inter-limb isokinetic strength differences were greater than inter-limb central activation ratio differences at all joint angles (P = 0.003). Interestingly, inter-limb deficits between measures were not strongly correlated, suggesting that these measurements may be evaluating completely different phenomena within the neuromuscular system. These measurement techniques may provide unique information regarding neuromuscular function, suggesting that researchers and clinicians must utilize information from both techniques to determine the true clinical nature of inter-limb deficits.

  3. 21 CFR 890.3420 - External limb prosthetic component.

    Science.gov (United States)

    2010-04-01

    ... total prosthesis. Examples of external limb prosthetic components include the following: Ankle, foot... shoulder joint components; and cable and prosthesis suction valves. (b) Classification. Class I...

  4. Development of a totally implantable artificial larynx

    NARCIS (Netherlands)

    Verkerke, GJ; Veenstra, Aalze; de Vries, MP; Schutte, HK; Busscher, HJ; Herrmann, IF; Van der Mei, HC; Rakhorst, G; Clements, MP

    1996-01-01

    Background. The consequences of a life-saving laryngectomy are still very distressing. The Eureka project "Artificial Larynx" aims at realization of an implantable artificial larynx to eliminate all drawbacks. Methods. The artificial larynx will consist of artificial vocal folds of adjustable pitch

  5. Anatomical and biomechanical traits of broiler chickens across ontogeny. Part II. Body segment inertial properties and muscle architecture of the pelvic limb

    Directory of Open Access Journals (Sweden)

    Heather Paxton

    2014-07-01

    Full Text Available In broiler chickens, genetic success for desired production traits is often shadowed by welfare concerns related to musculoskeletal health. Whilst these concerns are clear, a viable solution is still elusive. Part of the solution lies in knowing how anatomical changes in afflicted body systems that occur across ontogeny influence standing and moving. Here, to demonstrate these changes we quantify the segment inertial properties of the whole body, trunk (legs removed and the right pelvic limb segments of five broilers at three different age groups across development. We also consider how muscle architecture (mass, fascicle length and other properties related to mechanics changes for selected muscles of the pelvic limb. All broilers used had no observed lameness, but we document the limb pathologies identified post mortem, since these two factors do not always correlate, as shown here. The most common leg disorders, including bacterial chondronecrosis with osteomyelitis and rotational and angular deformities of the lower limb, were observed in chickens at all developmental stages. Whole limb morphology is not uniform relative to body size, with broilers obtaining large thighs and feet between four and six weeks of age. This implies that the energetic cost of swinging the limbs is markedly increased across this growth period, perhaps contributing to reduced activity levels. Hindlimb bone length does not change during this period, which may be advantageous for increased stability despite the increased energetic costs. Increased pectoral muscle growth appears to move the centre of mass cranio-dorsally in the last two weeks of growth. This has direct consequences for locomotion (potentially greater limb muscle stresses during standing and moving. Our study is the first to measure these changes in the musculoskeletal system across growth in chickens, and reveals how artificially selected changes of the morphology of the pectoral apparatus may cause

  6. Residual stress distribution in rabbit limb bones.

    Science.gov (United States)

    Yamada, Satoshi; Tadano, Shigeru; Fujisaki, Kazuhiro

    2011-04-29

    The presence of the residual stresses in bone tissue has been noted and the authors have reported that there are residual stresses in bone tissue. The aim of our study is to measure the residual stress distribution in the cortical bone of the extremities of vertebrates and to describe the relationships with the osteon population density. The study used the rabbit limb bones (femur, tibia/fibula, humerus, and radius/ulna) and measured the residual stresses in the bone axial direction at anterior and posterior positions on the cortical surface. The osteons at the sections at the measurement positions were observed by microscopy. As a result, the average stresses at the hindlimb bones and the forelimb bones were 210 and 149 MPa, respectively. In the femur, humerus, and radius/ulna, the residual stresses at the anterior position were larger than those at the posterior position, while in the tibia, the stress at the posterior position was larger than that at the anterior position. Further, in the femur and humerus, the osteon population densities in the anterior positions were larger than those in the posterior positions. In the tibia, the osteon population density in the posterior position was larger than that in the anterior position. Therefore, tensile residual stresses were observed at every measurement position in the rabbit limb bones and the value of residual stress correlated with the osteon population density (r=0.55, P<0.01).

  7. Altitude Registration of Limb-Scattered Radiation

    Science.gov (United States)

    Moy, Leslie; Bhartia, Pawan K.; Jaross, Glen; Loughman, Robert; Kramarova, Natalya; Chen, Zhong; Taha, Ghassan; Chen, Grace; Xu, Philippe

    2017-01-01

    One of the largest constraints to the retrieval of accurate ozone profiles from UV backscatter limb sounding sensors is altitude registration. Two methods, the Rayleigh scattering attitude sensing (RSAS) and absolute radiance residual method (ARRM), are able to determine altitude registration to the accuracy necessary for long-term ozone monitoring. The methods compare model calculations of radiances to measured radiances and are independent of onboard tracking devices. RSAS determines absolute altitude errors, but, because the method is susceptible to aerosol interference, it is limited to latitudes and time periods with minimal aerosol contamination. ARRM, a new technique introduced in this paper, can be applied across all seasons and altitudes. However, it is only appropriate for relative altitude error estimates. The application of RSAS to Limb Profiler (LP) measurements from the Ozone Mapping and Profiler Suite (OMPS) on board the Suomi NPP (SNPP) satellite indicates tangent height (TH) errors greater than 1 km with an absolute accuracy of +/-200 m. Results using ARRM indicate a approx. 300 to 400m intra-orbital TH change varying seasonally +/-100 m, likely due to either errors in the spacecraft pointing or in the geopotential height (GPH) data that we use in our analysis. ARRM shows a change of approx. 200m over 5 years with a relative accuracy (a long-term accuracy) of 100m outside the polar regions.

  8. Limb Regeneration in Axolotl: Is It Superhealing?

    Directory of Open Access Journals (Sweden)

    Stéphane Roy

    2006-01-01

    Full Text Available The ability of axolotls to regenerate their limbs is almost legendary. In fact, urodeles such as the axolotl are the only vertebrates that can regenerate multiple structures like their limbs, jaws, tail, spinal cord, and skin (the list goes on throughout their lives. It is therefore surprising to realize, although we have known of their regenerative potential for over 200 years, how little we understand the mechanisms behind this achievement of adult tissue morphogenesis. Many observations can be drawn between regeneration and other disciplines such as development and wound healing. In this review, we present new developments in functional analysis that will help to address the role of specific genes during the process of regeneration. We also present an analysis of the resemblance between wound healing and regeneration, and discuss whether axolotls are superhealers. A better understanding of these animals' regenerative capacity could lead to major benefits by providing regenerative medicine with directions on how to develop therapeutic approaches leading to regeneration in humans.

  9. Line Caustic Microlensing and Limb Darkening

    CERN Document Server

    Rhie, S H; Rhie, Sun Hong; Bennett, David P.

    1999-01-01

    In a line caustic crossing microlensing event, the caustic line moving across the surface of the source star provides a direct method to measure the integrated luminosity profile of the star. Combined with the enormous brightening at the caustic crossings, microlensing offers a promising tool for studying stellar luminosity profiles. We derive the amplification behavior of the two extra images that become partial images conjoined across the critical curve at a line caustic crossing. We identify the multiplicative factors that depend on the caustic crossing point and the relative size of the star, and the shape function that depends on the stellar luminosity profile. We examine the analytic limb-darkening models -- linear, square root, and square -- using the analytic form of the shape function. We find that the microlensing lightcurves must be determined to an accuracy of better than 0.3-0.8% in order to be able to determine the linear limb-darkening parameter $c_1$ with precision of binaries as reported by P...

  10. Lower limb prosthesis utilisation by elderly amputees.

    Science.gov (United States)

    Bilodeau, S; Hébert, R; Desrosiers, J

    2000-08-01

    The goal of prosthetic rehabilitation is to compensate for the loss of a limb by amputation by, in the case of a lower limb, encouraging walking, and to achieve the same level of autonomy as prior to the amputation. However, because of difficulties walking, elderly amputees may use their prosthesis to a greater or lesser degree or simply stop using it during the rehabilitation period. The objective of this research was to study factors such as physical and mental health, rehabilitation, physical independence and satisfaction with the prosthesis to understand why amputees use their prosthesis or not. The sample was composed of 65 unilateral vascular amputees 60 years old or over living at home. The information was collected from medical records, by telephone interview and by mail questionnaire. Prosthesis use was measured by a questionnaire on amputee activities developed by Day (1981). Eighty-one per cent (81%) of the subjects wore their prosthesis every day and 89% of this group wore it 6 hours or more per day. Less use of the prosthesis was significantly related to age, female gender, possession of a wheelchair, level of physical disability, cognitive impairment, poorer self-perceived health and the amputee's dissatisfaction. A multiple regression analysis showed that satisfaction, not possessing a wheelchair and cognitive integrity explained 46% of the variance in prosthesis use.

  11. [Arterial surgery of the upper limb].

    Science.gov (United States)

    Perrault, L; Lassonde, J; Laurendeau, F

    1991-01-01

    Arterial surgery of the upper limb represents 2.5% of peripheral vascular procedures in our center. From 1976 to 1989, 58 procedures were performed in 45 patients. There were 26 men and 19 women with average age of 52 years, ranging from 6 to 92 years. These patients were grouped in three categories according to etiology: 1) trauma; 2) acute non traumatic ischemia and 3) chronic ischemia. Sixteen patients (35.5%) were operated on for arterial trauma including three false aneurysms. Blunt trauma was the cause in 9 patients, penetrating in 6 and iatrogenic in one. Angioplasty and primary end to end anastomosis were used in 6, bypass in 4, simple ligation in 3, thrombectomy in 3. The outcome was excellent in 15/16 (93%). Non traumatic acute ischemia occurred in 16 patients (35.5%) and was due to emboli of cardiac origin in 92%. All patients were treated by thromboembolectomy. This group had a high mortality (5/16, 31%) because of associated medical conditions. The third group of 13 patients (29%) underwent surgery for chronic ischemia of the upper limb localized to the subclavian artery in 92%. They were treated with carotid subclavian bypasses in 9, other types of bypass in 3 and endarterectomy in 1. Excellent results were obtained in 10/13 (78%). Overall, satisfactory results were obtained in 90% of surviving patients. Operative mortality was 11.1% and the amputation rate was 13%.

  12. Limb salvage: When, where, and how?

    Directory of Open Access Journals (Sweden)

    Ajay Puri

    2015-01-01

    Full Text Available From an era where amputation was the only option to the current day function preserving resections and complex reconstructions has been a major advance in the treatment of musculoskeletal sarcomas. The objectives of extremity reconstruction after oncologic resection include providing skeletal stability where necessary, adequate wound coverage to allow early subsequent adjuvant therapy, optimising the aesthetic outcome and preservation of functional capability with early return to function. This article highlights the concepts of surgical margins in oncology, discusses the principles governing safe surgical resection in these tumors and summarises the current modalities and recent developments relevant to reconstruction after limb salvage. The rationale of choice of a particular resection modality and the unique challenges of reconstruction in skeletally immature individuals are also discussed. Striking the right balance between adequate resection, while yet retaining or reconstructing tissue for acceptable function and cosmesis is a difficult task. Complications are not uncommon and patients and their families need to be counseled regarding the potential setbacks that may occur in the course of their eventual road to recovery, Limb salvage entails a well orchestrated effort involving various specialties and better outcomes are likely to be achieved with centralization of expertise at regional centers.

  13. New Lower-Limb Gait Asymmetry Indices Based on a Depth Camera

    Directory of Open Access Journals (Sweden)

    Edouard Auvinet

    2015-02-01

    Full Text Available Background: Various asymmetry indices have been proposed to compare the spatiotemporal, kinematic and kinetic parameters of lower limbs during the gait cycle. However, these indices rely on gait measurement systems that are costly and generally require manual examination, calibration procedures and the precise placement of sensors/markers on the body of the patient. Methods: To overcome these issues, this paper proposes a new asymmetry index, which uses an inexpensive, easy-to-use and markerless depth camera (Microsoft Kinect™ output. This asymmetry index directly uses depth images provided by the Kinect™ without requiring joint localization. It is based on the longitudinal spatial difference between lower-limb movements during the gait cycle. To evaluate the relevance of this index, fifteen healthy subjects were tested on a treadmill walking normally and then via an artificially-induced gait asymmetry with a thick sole placed under one shoe. The gait movement was simultaneously recorded using a Kinect™ placed in front of the subject and a motion capture system. Results: The proposed longitudinal index distinguished asymmetrical gait (p < 0.001, while other symmetry indices based on spatiotemporal gait parameters failed using such Kinect™ skeleton measurements. Moreover, the correlation coefficient between this index measured by Kinect™ and the ground truth of this index measured by motion capture is 0.968. Conclusion: This gait asymmetry index measured with a Kinect™ is low cost, easy to use and is a promising development for clinical gait analysis.

  14. Characterisation of dynamic couplings at lower limb residuum/socket interface using 3D motion capture.

    Science.gov (United States)

    Tang, Jinghua; McGrath, Michael; Laszczak, Piotr; Jiang, Liudi; Bader, Dan L; Moser, David; Zahedi, Saeed

    2015-12-01

    Design and fitting of artificial limbs to lower limb amputees are largely based on the subjective judgement of the prosthetist. Understanding the science of three-dimensional (3D) dynamic coupling at the residuum/socket interface could potentially aid the design and fitting of the socket. A new method has been developed to characterise the 3D dynamic coupling at the residuum/socket interface using 3D motion capture based on a single case study of a trans-femoral amputee. The new model incorporated a Virtual Residuum Segment (VRS) and a Socket Segment (SS) which combined to form the residuum/socket interface. Angular and axial couplings between the two segments were subsequently determined. Results indicated a non-rigid angular coupling in excess of 10° in the quasi-sagittal plane and an axial coupling of between 21 and 35 mm. The corresponding angular couplings of less than 4° and 2° were estimated in the quasi-coronal and quasi-transverse plane, respectively. We propose that the combined experimental and analytical approach adopted in this case study could aid the iterative socket fitting process and could potentially lead to a new socket design.

  15. Decoding Lower Limb Muscle Activity and Kinematics from Cortical Neural Spike Trains during Monkey Performing Stand and Squat Movements

    Science.gov (United States)

    Ma, Xuan; Ma, Chaolin; Huang, Jian; Zhang, Peng; Xu, Jiang; He, Jiping

    2017-01-01

    Extensive literatures have shown approaches for decoding upper limb kinematics or muscle activity using multichannel cortical spike recordings toward brain machine interface (BMI) applications. However, similar topics regarding lower limb remain relatively scarce. We previously reported a system for training monkeys to perform visually guided stand and squat tasks. The current study, as a follow-up extension, investigates whether lower limb kinematics and muscle activity characterized by electromyography (EMG) signals during monkey performing stand/squat movements can be accurately decoded from neural spike trains in primary motor cortex (M1). Two monkeys were used in this study. Subdermal intramuscular EMG electrodes were implanted to 8 right leg/thigh muscles. With ample data collected from neurons from a large brain area, we performed a spike triggered average (SpTA) analysis and got a series of density contours which revealed the spatial distributions of different muscle-innervating neurons corresponding to each given muscle. Based on the guidance of these results, we identified the locations optimal for chronic electrode implantation and subsequently carried on chronic neural data recordings. A recursive Bayesian estimation framework was proposed for decoding EMG signals together with kinematics from M1 spike trains. Two specific algorithms were implemented: a standard Kalman filter and an unscented Kalman filter. For the latter one, an artificial neural network was incorporated to deal with the nonlinearity in neural tuning. High correlation coefficient and signal to noise ratio between the predicted and the actual data were achieved for both EMG signals and kinematics on both monkeys. Higher decoding accuracy and faster convergence rate could be achieved with the unscented Kalman filter. These results demonstrate that lower limb EMG signals and kinematics during monkey stand/squat can be accurately decoded from a group of M1 neurons with the proposed

  16. Decoding Lower Limb Muscle Activity and Kinematics from Cortical Neural Spike Trains during Monkey Performing Stand and Squat Movements.

    Science.gov (United States)

    Ma, Xuan; Ma, Chaolin; Huang, Jian; Zhang, Peng; Xu, Jiang; He, Jiping

    2017-01-01

    Extensive literatures have shown approaches for decoding upper limb kinematics or muscle activity using multichannel cortical spike recordings toward brain machine interface (BMI) applications. However, similar topics regarding lower limb remain relatively scarce. We previously reported a system for training monkeys to perform visually guided stand and squat tasks. The current study, as a follow-up extension, investigates whether lower limb kinematics and muscle activity characterized by electromyography (EMG) signals during monkey performing stand/squat movements can be accurately decoded from neural spike trains in primary motor cortex (M1). Two monkeys were used in this study. Subdermal intramuscular EMG electrodes were implanted to 8 right leg/thigh muscles. With ample data collected from neurons from a large brain area, we performed a spike triggered average (SpTA) analysis and got a series of density contours which revealed the spatial distributions of different muscle-innervating neurons corresponding to each given muscle. Based on the guidance of these results, we identified the locations optimal for chronic electrode implantation and subsequently carried on chronic neural data recordings. A recursive Bayesian estimation framework was proposed for decoding EMG signals together with kinematics from M1 spike trains. Two specific algorithms were implemented: a standard Kalman filter and an unscented Kalman filter. For the latter one, an artificial neural network was incorporated to deal with the nonlinearity in neural tuning. High correlation coefficient and signal to noise ratio between the predicted and the actual data were achieved for both EMG signals and kinematics on both monkeys. Higher decoding accuracy and faster convergence rate could be achieved with the unscented Kalman filter. These results demonstrate that lower limb EMG signals and kinematics during monkey stand/squat can be accurately decoded from a group of M1 neurons with the proposed

  17. Promise of a Low Power Mobile CPU based Embedded System in Artificial Leg Control

    Science.gov (United States)

    Hernandez, Robert; Zhang, Fan; Zhang, Xiaorong; Huang, He; Yang, Qing

    2013-01-01

    This paper presents the design and implementation of a low power embedded system using mobile processor technology (Intel Atom™ Z530 Processor) specifically tailored for a neural-machine interface (NMI) for artificial limbs. This embedded system effectively performs our previously developed NMI algorithm based on neuromuscular-mechanical fusion and phase-dependent pattern classification. The analysis shows that NMI embedded system can meet real-time constraints with high accuracies for recognizing the user's locomotion mode. Our implementation utilizes the mobile processor efficiently to allow a power consumption of 2.2 watts and low CPU utilization (less than 4.3%) while executing the complex NMI algorithm. Our experiments have shown that the highly optimized C program implementation on the embedded system has superb advantages over existing PC implementations on MATLAB. The study results suggest that mobile-CPU-based embedded system is promising for implementing advanced control for powered lower limb prostheses. PMID:23367113

  18. [The use of a synthetic vascular artificial prosthesis or arterial homograft in cases of patients with the arteriosclerosis and terminal insufficiency of kidney cured by the kidney transplantation].

    Science.gov (United States)

    Pupka, Artur; Blocher, Dariusz; Staniszewski, Tomasz; Płonek, Tomasz; Bogdan, Justyna

    2009-01-01

    Arterial transplantations were practiced in the vascular surgery since the beginning of her formation but without successes in the distant observation. Transplantation of a kidney is a routine conduct in the treatment of the decadent incapacity of a kidney. The dissertation concerns a use of arterial allografts kept using a method of a cold ischaemia in the protective liquid or synthetic vascular dacron artificial limbs or PTFE used as arterial foot-bridges at patients with the atherosclerotic obstruction aortal-pelvic, treated with the kidney transplantation. The arterial transplant is created from the aorta, arteria iliacas common and externa, femoral arteries common and superficial. A tissue material is kept using the method of the cold ischaemia and practical as the aortal foot-bridge-femoral or aortal-two-femoral at classified earlier patients being subjecteds to transfusion. The other way of a transplantation of a kidney at patients with the arteriosclerosis is the realization earlier or one-temporarily the vascular foot-bridge with use of the synthetic artificial limb. It seems that vascular artificial limbs about enlarged resistance on the contagion should be used in such a case. Sonographic examinations with duplex doppler and angiography are performed in all cases. The analysis of such cures can make a creation of the most profitable algorithm of the conduct possible in cases of patients suffering from ischaemia of lower limbs and requiring a transplantation of a kidney because of its incapacity.

  19. Transient alien limb phenomenon in right frontoparietal infarction

    Directory of Open Access Journals (Sweden)

    Panda Samhita

    2010-01-01

    Full Text Available Alien limb phenomenon is associated with different neurological disorders, such as stroke and corticobasal degeneration. It is usually caused by involvement of the corpus callosum, with or without the frontal regions. Rarely, it can result from insult in the posterior cerebral artery territory. Alien limb phenomenon is generally persistent. Here, an unusual case of transient alien hand phenomenon is reported.

  20. Fundamental ratios and logarithmic periodicity in human limb bones.

    Science.gov (United States)

    Pietak, Alexis; Ma, Siyan; Beck, Caroline W; Stringer, Mark D

    2013-05-01

    Fundamental mathematical relationships are widespread in biology yet there is little information on this topic with regard to human limb bone lengths and none related to human limb bone volumes. Forty-six sets of ipsilateral upper and lower limb long bones and third digit short bones were imaged by computed tomography. Maximum bone lengths were measured manually and individual bone volumes calculated from computed tomography images using a stereologic method. Length ratios of femur : tibia and humerus : ulna were remarkably similar (1.21 and 1.22, respectively) and varied little (bone volume ratios varied much more than upper limb ratios. The relationship between bone length and volume was found to be well described by power laws, with R(2) values ranging from 0.983 to 0.995. The most striking finding was a logarithmic periodicity in bone length moving from distal to proximal up the limb (upper limb λ = 0.72, lower limb λ = 0.93). These novel data suggest that human limb bone lengths and volumes follow fundamental and highly conserved mathematical relationships, which may contribute to our understanding of normal and disordered growth, stature estimation, and biomechanics.

  1. Sex Differences in Limb and Joint Stiffness in Recreational Runners

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2015-09-01

    Full Text Available Purpose. Female runners are known to be at greater risk from chronic running injuries than age-matched males, although the exact mechanisms are often poorly understood. The aim of the current investigation was to determine if female recreational runners exhibit distinct limb and joint stiffness characteristics in relation to their male counterparts. Methods. Fourteen male and fourteen female runners ran over a force platform at 4.0 m · s-1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system operating at 250 Hz. Measures of limb and joint stiffness were calculated as a function of limb length and joint moments divided by the extent of limb and joint excursion. All stiffness and joint moment parameters were normalized to body mass. Sex differences in normalized limb and knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that normalized limb (male = 0.18 ± 0.07, female = 0.37 ± 0.10 kN · kg · m-1 and knee stiffness (male = 5.59 ± 2.02, female = 7.34 ± 1.78 Nm · kg · rad-1 were significantly greater in female runners. Conclusions. On the basis that normalized knee and limb stiffness were shown to be significantly greater in female runners, the findings from the current investigation may provide further insight into the aetiology of the distinct injury patterns observed between sexes.

  2. Micro-lightguide spectrophotometry for tissue perfusion in ischemic limbs

    DEFF Research Database (Denmark)

    Jørgensen, Lise Pyndt; Schroeder, Torben V

    2012-01-01

    To validate micro-lightguide spectrophotometry (O2C) in patients with lower limb ischemia and to compare results with those obtained from toe blood pressure.......To validate micro-lightguide spectrophotometry (O2C) in patients with lower limb ischemia and to compare results with those obtained from toe blood pressure....

  3. Primary Upper Limb Lymphedema: Case Report of a Rare Pathology

    Science.gov (United States)

    McFarlane, Michael EC

    2017-01-01

    Introduction Lymphedema is characterized by a defect in the lymphatic system that causes limb swelling. Impaired uptake and transport of lymphatic fluid through lymphatic vessels causes accumulation of protein-rich fluid in the interstitial spaces, which leads to swelling of the limb. Primary lymphedema often presents at birth. The rare cases that arise after age 35 years are described as lymphedema tarda. The great majority of patients with lymphedema have swelling of the lower limbs—upper limb lymphedema is a rare disorder. Case Presentation An 84-year-old woman presented with a 3-year history of unilateral swelling of the right upper limb. There were no constitutional symptoms and no evidence of lymphadenopathy or systemic disease. Blood tests, carcinoembryonic antigen test, computed tomography scans, and venous Doppler ultrasound were all normal. The diagnosis was primary upper limb lymphedema. Discussion The swelling that occurs in upper limb lymphedema is permanent and usually extends to the hand. About one-third of patients with this condition also present with lower limb lymphedema. Thorough investigations are warranted in cases of unilateral upper limb lymphedema to rule out occult malignancy and systemic disease. PMID:28080951

  4. Lower limb deficient children in the Netherlands : epidemiological aspects

    NARCIS (Netherlands)

    Rijnders, LJM; Boonstra, AM; Groothoff, JW; Cornel, MC; Eisma, WH

    2000-01-01

    information on the characteristics of children with limb deficiencies and amputations in the Netherlands is largely lacking. The present study aimed to collect data about the prevalence of congenital deficiencies, the ratio of congenital to acquired limb deficiencies, types of lower leg deficiency o

  5. Critical evaluation of endovascular surgery for limb salvage.

    Science.gov (United States)

    Lucas, Layla C; Mills, Joseph L

    2011-01-01

    Rest pain, tissue loss, and gangrene are manifestations of critical limb ischemia caused by peripheral arterial disease and define a patient subgroup at highest risk for major limb amputation. Patients with nonhealing lower extremity wounds should be screened for the risk factors for peripheral arterial disease and offered noninvasive vascular testing. The diagnosis of critical limb ischemia mandates prompt institution of medical and surgical management to achieve the best chance of limb salvage. Surgical intervention has evolved from primary amputation to open bypass to the present era of endovascular therapy. The goals of surgical bypass and endovascular therapy are to improve perfusion sufficiently to permit healing. Despite poorer patency rates and the more frequent need for reintervention, endovascular therapy has been shown in multiple retrospective studies to achieve limb salvage similar to open bypass. Only one large, prospective, randomized controlled trial exists comparing open bypass with endovascular therapy: The Bypass versus Angioplasty in Severe Limb Ischemia of the Leg (BASIL) trial. Close clinical surveillance and serial monitoring of limb perfusion by means of noninvasive arterial studies are needed to determine the need for further vascular intervention. Limb salvage patients suffer from multiple comorbidities and benefit from a multidisciplinary, team approach to care.

  6. Cell to cell signalling during vertebrate limb bud development

    NARCIS (Netherlands)

    Panman, Lia

    2004-01-01

    Communication between cells is essential during embryonic development. The vertebrate limb bud provides us a model to study signalling interactions between cells during patterning of embryonic tissues and organogenesis. In chapter 1 I give an introduction about limb bud development that is focussed

  7. Upper Limb Ischemic Gangrene as a Complication of Hemodialysis Access

    Directory of Open Access Journals (Sweden)

    Shamir O. Cawich

    2015-01-01

    Full Text Available Upper limb ischemia is a well-recognized complication of dialysis access creation but progression to gangrene is uncommon. We report a case of upper limb ischemic gangrene and discuss the lessons learned during the management of this case. Clinicians must be vigilant for this complication and they should be reminded that it requires urgent management to prevent tissue loss.

  8. Prenatal MRI evaluation of limb-body wall complex

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre-Pascual, Elisa [Perelman School of Medicine at the University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Hospital Universitario Doce de Octubre, Department of Radiology, Madrid (Spain); Epelman, Monica [Perelman School of Medicine at the University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Nemours Children' s Hospital, Department of Medical Imaging, Orlando, FL (United States); Johnson, Ann M.; Chauvin, Nancy A.; Coleman, Beverly G.; Victoria, Teresa [Perelman School of Medicine at the University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States)

    2014-11-15

    The sonographic (US) features of limb-body wall complex have been well documented; however the literature regarding the findings on MRI in limb-body wall complex is scant. To characterize the prenatal MRI features of limb-body wall complex. We performed a retrospective review of all MRI scans of fetuses diagnosed with limb-body wall complex at our institution from 2001 to 2011. Fetuses without correlating US scans or follow-up information were excluded. Three pediatric radiologists blinded to the specific US findings reviewed the prenatal MRIs. Images were evaluated for the organ location and attachment, the body part affected, characterization of the body wall defect, and spinal, limb and umbilical cord abnormalities. Ten subjects met inclusion criteria. MRI was able to detect and characterize the body part affected and associated abnormalities. All fetuses had ventral wall defects, a small thorax and herniated liver and bowel. The kidneys were extracorporeal in three cases. The extruded organs were attached to the placenta or the uterine wall in all cases. Abnormal spinal curvatures of various degrees of severity were present in all cases. Eight cases had a short, uncoiled cord. Limb anomalies were present in 6 of the 10 cases. We illustrate the common fetal MRI findings of limb-body wall complex. The prenatal diagnosis of limb-body wall complex and the differentiation of this defect from treatable abdominal wall defects are crucial to providing appropriate guidance for patient counseling and management. (orig.)

  9. Doctors Try Brain-Training to Curb 'Phantom Limb Pain'

    Science.gov (United States)

    ... with the study. "The problem with having a prosthetic limb is that when you try to control that hand, it does not translate. You use other parts ... needed for a patient to move their "phantom" hand, and linked those signals to a robot prosthetic limb. Patients experienced an increase in phantom pain ...

  10. Limb-Darkening Coefficients for Eclipsing White Dwarfs

    CERN Document Server

    Gianninas, A; Kilic, Mukremin; Bergeron, P

    2013-01-01

    We present extensive calculations of linear and non-linear limb-darkening coefficients as well as complete intensity profiles appropriate for modeling the light-curves of eclipsing white dwarfs. We compute limb-darkening coefficients in the Johnson-Kron-Cousins UBVRI photometric system as well as the Large Synoptic Survey Telescope (LSST) ugrizy system using the most up-to-date model atmospheres available. In all, we provide the coefficients for seven different limb-darkening laws. We describe the variations of these coefficients as a function of the atmospheric parameters, including the effects of convection at low effective temperatures. Finally, we discuss the importance of having readily available limb-darkening coefficients in the context of present and future photometric surveys like the LSST, Palomar Transient Factory (PTF), and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The LSST, for example, may find ~10^5 eclipsing white dwarfs. The limb-darkening calculations presented h...

  11. Computational aerodynamics and artificial intelligence

    Science.gov (United States)

    Mehta, U. B.; Kutler, P.

    1984-01-01

    The general principles of artificial intelligence are reviewed and speculations are made concerning how knowledge based systems can accelerate the process of acquiring new knowledge in aerodynamics, how computational fluid dynamics may use expert systems, and how expert systems may speed the design and development process. In addition, the anatomy of an idealized expert system called AERODYNAMICIST is discussed. Resource requirements for using artificial intelligence in computational fluid dynamics and aerodynamics are examined. Three main conclusions are presented. First, there are two related aspects of computational aerodynamics: reasoning and calculating. Second, a substantial portion of reasoning can be achieved with artificial intelligence. It offers the opportunity of using computers as reasoning machines to set the stage for efficient calculating. Third, expert systems are likely to be new assets of institutions involved in aeronautics for various tasks of computational aerodynamics.

  12. Knitting and weaving artificial muscles

    Science.gov (United States)

    Maziz, Ali; Concas, Alessandro; Khaldi, Alexandre; Stålhand, Jonas; Persson, Nils-Krister; Jager, Edwin W. H.

    2017-01-01

    A need exists for artificial muscles that are silent, soft, and compliant, with performance characteristics similar to those of skeletal muscle, enabling natural interaction of assistive devices with humans. By combining one of humankind’s oldest technologies, textile processing, with electroactive polymers, we demonstrate here the feasibility of wearable, soft artificial muscles made by weaving and knitting, with tunable force and strain. These textile actuators were produced from cellulose yarns assembled into fabrics and coated with conducting polymers using a metal-free deposition. To increase the output force, we assembled yarns in parallel by weaving. The force scaled linearly with the number of yarns in the woven fabric. To amplify the strain, we knitted a stretchable fabric, exhibiting a 53-fold increase in strain. In addition, the textile construction added mechanical stability to the actuators. Textile processing permits scalable and rational production of wearable artificial muscles, and enables novel ways to design assistive devices. PMID:28138542

  13. Artificial sweeteners: safe or unsafe?

    Science.gov (United States)

    Qurrat-ul-Ain; Khan, Sohaib Ahmed

    2015-02-01

    Artificial sweeteners or intense sweeteners are sugar substitutes that are used as an alternative to table sugar. They are many times sweeter than natural sugar and as they contain no calories, they may be used to control weight and obesity. Extensive scientific research has demonstrated the safety of the six low-calorie sweeteners currently approved for use in foods in the U.S. and Europe (stevia, acesulfame-K, aspartame, neotame, saccharin and sucralose), if taken in acceptable quantities daily. There is some ongoing debate over whether artificial sweetener usage poses a health threat .This review article aims to cover thehealth benefits, and risks, of consuming artificial sweeteners, and discusses natural sweeteners which can be used as alternatives.

  14. [Implantation of the artificial retina].

    Science.gov (United States)

    Yagi, T; Hayashida, Y

    1999-05-01

    In some degenerative retinal diseases, e.g., retinitis pigmentosa and age-related macular degeneration, the photoreceptors are destroyed to cause serious visual defects. Recent studies on blind human subjects revealed that a large number of ganglion cells remains intact and is capable of transmitting signals to the brain to evoke partial visual perception. This provided hope to compensate for the visual defects with retinal prostheses. The recent progress of microfabrication technique made it possible to implement the Vary Large Scale Integrated circuit, the artificial retina, which emulates a part of retinal function. The idea of implanting the artificial retina to the patients was proposed recently and experiments using animals have been put into practice. This article surveys the front line of the artificial retina implantation.

  15. Artificial heart for humanoid robot

    Science.gov (United States)

    Potnuru, Akshay; Wu, Lianjun; Tadesse, Yonas

    2014-03-01

    A soft robotic device inspired by the pumping action of a biological heart is presented in this study. Developing artificial heart to a humanoid robot enables us to make a better biomedical device for ultimate use in humans. As technology continues to become more advanced, the methods in which we implement high performance and biomimetic artificial organs is getting nearer each day. In this paper, we present the design and development of a soft artificial heart that can be used in a humanoid robot and simulate the functions of a human heart using shape memory alloy technology. The robotic heart is designed to pump a blood-like fluid to parts of the robot such as the face to simulate someone blushing or when someone is angry by the use of elastomeric substrates and certain features for the transport of fluids.

  16. Contact dermatitis to a limb prosthesis.

    Science.gov (United States)

    Sood, Apra; Taylor, James S; Billock, John N

    2003-09-01

    PROSTHESIS USERS commonly develop various skin problems on the residual limb, directly under the prosthetic device when the device is in direct contact with the skin. Prolonged occlusion and humidity increase the likelihood of developing contact sensitivity to moisturizing creams, medicaments, and materials in the prosthesis itself.1 Allergic contact dermatitis to various prosthetic design materials is uncommon, and the relevance of positive patch-test results to chemicals present in prostheses may be difficult to establish. Most reports of allergic contact dermatitis to prostheses have been concerned with surgical amputees and not congenital amputees. We report a 5-year-old boy with a transverse partial hemimelia who developed allergic contact dermatitis to an adhesive used in his myoelectric prosthesis. Unlike most prostheses, myoelectric prostheses are worn directly against the skin, for surface electromyography electrode contact.

  17. Magnetic Fields in Limb Solar Flares

    Science.gov (United States)

    Lozitsky, V. G.; Lozitska, N. I.; Botygina, O. A.

    2013-02-01

    Two limb solar flares, of 14 July 2005 and 19 July 2012, of importance X1.2 and M7.7, are analyzed at present work. Magnetic field strength in named flares are investigated by Stokes I±V profiles of Hα and D3 HeI lines. There are direct evidences to the magnetic field inhomogeneity in flares, in particular, non-paralelism of bisectors in I+V and I-V profiles. In some flare places, the local maximums of bisectors splitting were found in both lines. If these bisector splittings are interpreted as Zeeman effect manifestation, the following magnetic field strengths reach up to 2200 G in Hα and 1300 G in D3. According to calculations, the observed peculiarities of line profiles may indicate the existence of optically thick emissive small-scale elements with strong magnetic fields and lowered temperature.

  18. Post-transplant distal limb syndrome

    Directory of Open Access Journals (Sweden)

    María Florencia Borghi Torzillo

    2017-02-01

    Full Text Available The post-transplant distal limb syndrome is a not well known entity, with a prevalence of 5% in patients with renal transplant. Its diagnosis is based on clinical symptoms, bone scintigraphy and MRI, it has a benign course and the patient recovers without sequel. We present the case of a 37-year-old male, with medical history of hypertension, Berger's disease in 1999 that required dialysis three times a week for four years (2009-2013 and renal transplant in 2013. The patient consults on January 2014 referring severe pain in both feet, with sudden onset; he remembers the exact date of the beginning of the pain and denies trauma, pain prevents ambulation. The bone scintigraphy shows pathological uptake in both feet with no difference between the two. Although there is no treatment for this disease, it has a benign course

  19. How x rays inhibit amphibian limb regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Maden, M.; Wallace, H.

    1976-07-01

    The effects of an inhibiting dose of 2,000 rad of x-rays on the regenerating limbs of axolotl larvae have been examined in a histological and cytological study. Particular attention was paid to the mitotic indices of normal and irradiated epidermal and blastemal cells. Both the characteristic pattern of epidermal mitotic stimulation which normally follows amputation and the later increase in blastemal mitoses are suppressed by irradiation. In most cells the effects are permanent, but in a small proportion a mitotic delay is induced and upon subsequent division chromosome damage in the form of micronuclei is revealed. Thus irradiated cells which do divide almost certainly die. These results are discussed in relation to other theories of x-ray inhibition of regeneration with particular reference to the view that irradiated cells can be reactivated.

  20. Optimising Body Layout Design of Limbed Machines

    Institute of Scientific and Technical Information of China (English)

    Shu-jun Zhang; Jin Tong; Kevin Hapeshi; Dong-hui Chen

    2007-01-01

    This paper presents our efforts to explain why mammals have large thigh muscles while insects have small ones. After a discussion of this observation a definition of body foot ratio is defined which describes how animals stand and how their legs are arranged. To investigate the mechanics, we present a closed optimum solution of the body foot ratio for a 2D two-leg walking machine. A multi-walker is used as a case for 3D general analysis, and the numerical simulation is presented. Both 2D and 3D case studies can explain the above observations of mammals and insects. These findings can also be used as a guide for the design of man-made limbed machines.

  1. Limb bone morphology, bone strength, and cursoriality in lagomorphs.

    Science.gov (United States)

    Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

    2014-10-01

    The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which 'cursorial specialization' affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and μCT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high 'displacement advantage', permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with increasing

  2. MR imaging in congenital lower limb deformities

    Energy Technology Data Exchange (ETDEWEB)

    Laor, T. [Dept. of Radiology, Children`s Hospital and Harvard Medical School, Boston, MA (United States); Jaramillo, D. [Dept. of Radiology, Children`s Hospital and Harvard Medical School, Boston, MA (United States); Hoffer, F.A. [Dept. of Radiology, Children`s Hospital and Harvard Medical School, Boston, MA (United States); Kasser, J.R. [Dept. of Orthopedics, Children`s Hospital and Harvard Medical School, Boston, MA (United States)

    1996-06-01

    Treatment for children with cogenital deformities of the lower extremities may vary, depending on the state of the unossified skeletal structures and surrounding soft tissues. The purpose of our study was to demonstrate the spectrum of the osteochondral and extrasosseous abnormalities as depicted with MR imaging. We retrospectively reviewed MR examinations of 13 limbs of ten children (aged 1 month-9 years, mean 2.1 years) with longitudinal and transverse deformities of the lower extremities. The lesions imaged were fibular hemimelia (n=5), tibial hemimelia (n=5), and congenital constriction bands (n=3). Each examination was assessed for abnormalities in the osteocartilaginous and extraosseous (articular or periarticular components such as ligaments, tendons, and menisci; the muscles and the arteries) structures. Abnormalities were seen in all patients. Osteocartilaginous abnormalities in the patients with longitudinal deformities included abnormal distal femoral epiphyses, abnormal proximal tribial physes, hypertrophied and dislocated proximal fibular epiphyses, unsuspected fibular and tibial remnants, and absence or coalition of the tarsal bones. No osteocartilaginous abnormalities were seen in the patients with congential constriction bands. Articular abormalities in patients with either form of hemimelia included absent cruciate ligaments and menisci, dislocated or absent cartilaginous patellae, absent patellar tendons, and abnormal collateral ligaments. All but one limb imaged had absent or attenuated muscle groups. Of the nine MR arteriograms performed at the level of the knee, eight were abnormal. The normal popliteal trifurcation was absent or in an abnormal location. We conclude that MR imaging of children with congenital lower extremity deformities shows many osteochondral and extraosseous abnormalities that are not depicted by conventional radiogrpahy. This information can help to plan early surgical intervention and prosthetic rehabilitation. (orig.)

  3. Lower limb joint replacement in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Clement Nicholas D

    2012-06-01

    Full Text Available Abstract Introduction There is limited literature regarding the peri-operative and surgical management of patients with rheumatoid disease undergoing lower limb arthroplasty. This review article summarises factors involved in the peri-operative management of major lower limb arthroplasty surgery for patients with rheumatoid arthritis. Methods We performed a search of the medical literature, using the PubMed search engine (http://www.pubmed.gov. We used the following terms: ‘rheumatoid’ ‘replacement’ ‘arthroplasty’ and ‘outcome’. Findings The patient should be optimised pre-operatively using a multidisciplinary approach. The continued use of methotrexate does not increase infection risk, and aids recovery. Biologic agents should be stopped pre-operatively due the increased infection rate. Patients should be made aware of the increased risk of infection and periprosthetic fracture rates associated with their disease. The surgical sequence is commonly hip, knee and then ankle. Cemented total hip replacement (THR and total knee replacement (TKR have superior survival rates over uncemented components. The evidence is not clear regarding a cruciate sacrificing versus retaining in TKR, but a cruciate sacrificing component limits the risk early instability and potential revision. Patella resurfacing as part of a TKR is associated with improved outcomes. The results of total ankle replacement remain inferior to THR and TKR. RA patients achieve equivalent pain relief, but their rehabilitation is slower and their functional outcome is not as good. However, the key to managing these complicated patients is to work as part of a multidisciplinary team to optimise their outcome.

  4. Agent communication and artificial institutions

    OpenAIRE

    Fornara, Nicoletta; Viganò, Francesco; Colombetti, Marco

    2011-01-01

    In this paper we propose an application-independent model for the definition of artificial institutions that can be used to define open multi-agent systems. Such a model of institutional reality makes us able also to define an objective and external semantics of a commitment-based Agent Communication Language (ACL). In particular we propose to regard an ACL as a set of conventions to act on a fragment of institutional reality, defined in the context of an artificial institution. Another c...

  5. Training Applications of Artificial Intelligence.

    Science.gov (United States)

    1987-03-23

    nearifest tLer,sclvCs in ELO r operatii.L costs in the life C’VclE Of the ef’uijjteft. E F re\\ lously rcntione6 ey~ arrle of usingF the 1lirefineer...Ibid., p. 35. 4. Avron Barr and Edward Feigenbaum, The Handbook of Artificial Intelligence, Vol. 1, p. 2. 5. Wissam W. Ahmed, "Theories of Artificial...Barr, Avron and Geigenbaum, Edward A. ed. The Handbook of Arti- ficial Intelligence. Vol. 1. Stanford: heuristech Press. 1981. Gevartner, William B

  6. Rewritable artificial magnetic charge ice

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y. -L.; Xiao, Z. -L.; Snezhko, A.; Xu, J.; Ocola, L. E.; Divan, R.; Pearson, J. E.; Crabtree, G. W.; Kwok, W. -K.

    2016-05-19

    Artificial ices enable the study of geometrical frustration by design and through direct observation. However, it has proven difficult to achieve tailored long-range ordering of their diverse configurations, limiting both fundamental and applied research directions. We designed an artificial spin structure that produces a magnetic charge ice with tunable long-range ordering of eight different configurations. We also developed a technique to precisely manipulate the local magnetic charge states and demonstrate write-read-erase multifunctionality at room temperature. This globally reconfigurable and locally writable magnetic charge ice could provide a setting for designing magnetic monopole defects, tailoring magnonics, and controlling the properties of other two-dimensional materials.

  7. Fecundación artificial

    OpenAIRE

    2013-01-01

    Por Fecundación artificial se entiende, la fecundación de una hembra sin el servicio directo del macho, es decir la introducción al aparato genital femenino, del esperma que se ha recogido por medios artificiales. Esta fecundación, practicada en debidas condiciones, tiene el mismo efecto de la fecundación natural, con las ventajas que veremos más adelante. La fecundación artificial permite explotar un reproductor a su máximum de capacidad, ya que se considera, para no hacer cálculo...

  8. Artificial intelligence techniques in Prolog

    CERN Document Server

    Shoham, Yoav

    1993-01-01

    Artificial Intelligence Techniques in Prolog introduces the reader to the use of well-established algorithmic techniques in the field of artificial intelligence (AI), with Prolog as the implementation language. The techniques considered cover general areas such as search, rule-based systems, and truth maintenance, as well as constraint satisfaction and uncertainty management. Specific application domains such as temporal reasoning, machine learning, and natural language are also discussed.Comprised of 10 chapters, this book begins with an overview of Prolog, paying particular attention to Prol

  9. Limb lengthening in Africa: tibial lengthening indicated for limb length discrepancy and postosteomyelitis pseudarthrosis

    Directory of Open Access Journals (Sweden)

    Ibrahima F

    2014-05-01

    Full Text Available Farikou Ibrahima,1,2 Pius Fokam,2 Félicien Faustin Mouafo Tambo11Department of Surgery and Specialties, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, 2Department of Surgery, Douala General Hospital, Douala, CameroonBackground: We present a case of lengthening of a tibia to treat postosteomyelitis pseudarthrosis and limb length discrepancy by the Ilizarov device.Objective: The objective was to treat the pseudarthrosis and correct the consequent limb length discrepancy of 50 mm.Materials and methods: The patient was a 5-year-old boy. Osteotomy of the tibia, excision of fibrosis, and decortications were carried out. After a latency period of 5 days, the lengthening started at a rate of 1 mm per day.Results: The pseudarthrosis healed and the gained correction was 21.73%. The index consolidation was 49 days/cm. Minor complications were reported.Discussion: Osteomyelitis of long bones is a common poverty-related disease in Africa. The disease usually is diagnosed at an advanced stage with complications. In these conditions, treatment is much more difficult. Most surgical procedures treating this condition use the Ilizarov device. The most common reported surgical complications are refractures and recurrence of infection.Conclusion: This technique should be popularized in countries with limited resources because it would be an attractive alternative to the amputations that are sometimes performed.Keywords: Limb length discrepancy (LLD, bone gap, Ilizarov device

  10. Tactile, thermal, and electrical thresholds in patients with and without phantom limb pain after traumatic lower limb amputation

    Directory of Open Access Journals (Sweden)

    Li S

    2015-04-01

    Full Text Available Shengai Li,1,2 Danielle H Melton,1,2 Sheng Li1,2 1Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston, Houston, TX, USA; 2Neurorehabilitation Research Laboratory, TIRR Memorial Hermann Research Center, Houston, TX, USA Purpose: To examine whether there is central sensitization in patients with phantom limb pain (PLP after traumatic limb amputation. Methods: Seventeen patients after unilateral lower limb amputation secondary to trauma were enrolled. Ten patients had chronic PLP, while the other seven patients had no PLP. Tactile-sensation threshold, cold- and warm-sensation thresholds, cold- and heat-pain thresholds, electrical-sensation threshold (EST, and electrical-pain threshold on the distal residual limb and the symmetrical site on the sound limb were measured in all tested patients. Their thresholds were compared within the PLP and non-PLP group, and between the groups. Results: The novel findings included: 1 electrical-pain threshold was only decreased in the sound limb in the PLP group and there was no difference between two limbs in the non-PLP group, suggesting central sensitization in patients with PLP; and 2 EST was increased on the affected limb as compared to the sound limb within the PLP group, but there were no significant differences in EST between the PLP and non-PLP group. There were in general no significant differences in other tested thresholds within the groups and between groups. Conclusion: Our results demonstrate central sensitization in the patients with PLP after traumatic limb amputation. Keywords: central sensitization, pain threshold, human

  11. Functional reconstruction of ischemic contracture in the lower limb

    Institute of Scientific and Technical Information of China (English)

    TANG Hao; ZHANG Shao-cheng; TAN Zhang-yong; ZHU Hong-wei; ZHANG Qiu-lin; LI Ming

    2011-01-01

    Objective: To discuss the method of functional reconstruction of ischemic contracture in the lower limb and propose a classification protocol for ischemic contracture in the lower limb based on its severity and prognosis.Methods: Atotal of 42 patients with ischemic contracture in the lower limb were included in this study. According to different types of disturbance and degrees of severity,surgical reconstructions consisting of nerve decompression,tendon lengthening or transfer, intrinsic foot muscle release and sural-tibial nerve anastomosis were performed in every patient.Results: Postoperatively, all patients were able to walk on flat ground. Drop foot was corrected in 10 patients,and 5 patients still felt some difficulty during stair activity.Split Achilles tendon transfer to flexor hallucis longus tendon was performed in 12 patients, and their walking stability was improved. Seven patients accepted ipsilateral suraltibial nerve anastomosis, and sensitivity recovery reached to S2 in 2 patients and S3 in 5 patients.Conclusions: Ischemic contracture in the lower limb is a devastating complication after lower limb trauma. The prevention of contracture is much more important than the treatment of an established contracture. Split Achilles tendon transfer to flexor hallucis longus tendon and sural-tibial nerve anastomosis, which was initially implemented by us, could improve the functional recovery of ischemic contracture in lower limbs, and thus provides a new alternative for functional reconstruction of ischemic contracture in the lower limb.

  12. Capturing the Perceived Phantom Limb through Virtual Reality

    Directory of Open Access Journals (Sweden)

    Christian Rogers

    2016-01-01

    Full Text Available Phantom limb is the sensation amputees may feel when the missing limb is still attached to the body and is still moving as it would if it still existed. Despite there being between 50 and 80% of amputees who report neuropathic pain, also known as phantom limb pain (PLP, there is still little understanding of why PLP occurs. There are no fully effective long-term treatments available. One of the struggles with PLP is the difficulty for amputees to describe the sensations of their phantom limbs. The sensations may be of a limb that is in a position that is impossible for a normal limb to attain. The goal of this project was to treat those with PLP by developing a system to communicate the sensations those with PLP were experiencing accurately and easily through various hand positions using a model arm with a user friendly interface. The system was developed with Maya 3D animation software, the Leap Motion input device, and the Unity game engine. The 3D modeled arm was designed to mimic the phantom sensation being able to go beyond normal joint extensions of regular arms. The purpose in doing so was to obtain a true 3D visualization of the phantom limb.

  13. Limb Heaviness: A Perceptual Phenomenon Associated With Poststroke Fatigue?

    Science.gov (United States)

    Kuppuswamy, Annapoorna; Clark, Ella; Rothwell, John; Ward, Nick S

    2016-05-01

    Poststroke fatigue and limb heaviness are 2 perceptual problems that commonly occur after stroke. Previous work suggests that poststroke fatigue may be related to altered sensorimotor processing whereas limb heaviness is often considered an association of muscle weakness. To address the hypothesis that the perception of limb heaviness may also be a problem of altered sensorimotor control, we investigated whether it was more closely related to poststroke fatigue or muscle weakness. In 69 chronic stroke survivors, we found that those with high perceived limb heaviness (31 individuals) also reported significantly higher levels of fatigue (4.8/7) than those with no perceived limb heaviness (38 individuals, fatigue score = 2.68/7), but there was no difference in weakness between the 2 groups. This intriguing finding is discussed in relation to effort perception and sensory processing. The association between limb heaviness and poststroke fatigue and a dissociation from muscle weakness gives rise to the hypothesis that limb heaviness maybe a centrally arising sensorimotor disorder.

  14. Individual limb mechanical analysis of gait following stroke.

    Science.gov (United States)

    Mahon, Caitlin E; Farris, Dominic J; Sawicki, Gregory S; Lewek, Michael D

    2015-04-13

    The step-to-step transition of walking requires significant mechanical and metabolic energy to redirect the center of mass. Inter-limb mechanical asymmetries during the step-to-step transition may increase overall energy demands and require compensation during single-support. The purpose of this study was to compare individual limb mechanical gait asymmetries during the step-to-step transitions, single-support and over a complete stride between two groups of individuals following stroke stratified by gait speed (≥0.8 m/s or phases of a stride, as well as over a complete stride. Robust inter-limb asymmetries in mechanical power existed during walking after stroke; for both groups, the non-paretic limb produced significantly more positive net mechanical power than the paretic limb during all phases of a stride and over a complete stride. Interestingly, no differences in inter-limb mechanical power asymmetry were noted between groups based on walking speed, during any phase or over a complete stride. Paretic propulsion, however, was different between speed-based groups. The fact that paretic propulsion (calculated from anterior-posterior forces) is different between groups, but our measure of mechanical work (calculated from all three directions) is not, suggests that limb power output may be dominated by vertical components, which are required for upright support.

  15. MONITORING OF LOWER LIMB COMFORT AND INJURY IN ELITE FOOTBALL

    Directory of Open Access Journals (Sweden)

    Michael Kinchington

    2010-12-01

    Full Text Available The aim of the study was to examine the relation between lower limb comfort scores and injury and to measure the responsiveness of a lower limb comfort index (LLCI to changes over time, in a cohort of professional footballers. Lower limb comfort was recorded for each individual using a comfort index which assessed the comfort status of five anatomical segments and footwear. Specifically we tested the extent to which comfort zones as measured by the LLCI were related to injury measured as time loss events. The hypothesis for the study was that poor lower limb comfort is related to time loss events (training or match day. A total of 3524 player weeks of data was collected from 182 professional athletes encompassing three codes of football (Australian Rules, Rugby league, Rugby Union. The study was conducted during football competition periods for the respective football leagues and included a period of pre- season training. The results of regression indicated that poor lower limb comfort was highly correlated to injury (R2 =0.77 and accounted for 43.5 time loss events/ 1000hrs football exposure. While poor comfort was predictive of injury 47% of all time loss events it was not statistically relevant (R2 =0.18. The results indicate lower limb comfort can be used to assess the well-being of the lower limb; poor comfort is associated with injury, and the LLCI has good face validity and high criterion-related validity for the relationship between comfort and injury

  16. Artificial Intelligence Assists Ultrasonic Inspection

    Science.gov (United States)

    Schaefer, Lloyd A.; Willenberg, James D.

    1992-01-01

    Subtle indications of flaws extracted from ultrasonic waveforms. Ultrasonic-inspection system uses artificial intelligence to help in identification of hidden flaws in electron-beam-welded castings. System involves application of flaw-classification logic to analysis of ultrasonic waveforms.

  17. Artificial neural networks in medicine

    Energy Technology Data Exchange (ETDEWEB)

    Keller, P.E.

    1994-07-01

    This Technology Brief provides an overview of artificial neural networks (ANN). A definition and explanation of an ANN is given and situations in which an ANN is used are described. ANN applications to medicine specifically are then explored and the areas in which it is currently being used are discussed. Included are medical diagnostic aides, biochemical analysis, medical image analysis and drug development.

  18. Thinking, Creativity, and Artificial Intelligence.

    Science.gov (United States)

    DeSiano, Michael; DeSiano, Salvatore

    This document provides an introduction to the relationship between the current knowledge of focused and creative thinking and artificial intelligence. A model for stages of focused and creative thinking gives: problem encounter/setting, preparation, concentration/incubation, clarification/generation and evaluation/judgment. While a computer can…

  19. Artificial penile nodules: case reports.

    OpenAIRE

    Lim, K B; Seow, C.S.; Tulip, T; Daniel, M.; Vijayasingham, S M

    1986-01-01

    An interesting cultural practice of implanting foreign bodies under the skin of the penis for enhancing sexual excitement in the man's sexual partner is described. Recognition of this is important to venereologists because of their primary concern with the genital area. The term artificial penile nodule has been suggested for the condition resulting from this practice.

  20. Artificial Video for Video Analysis

    Science.gov (United States)

    Gallis, Michael R.

    2010-01-01

    This paper discusses the use of video analysis software and computer-generated animations for student activities. The use of artificial video affords the opportunity for students to study phenomena for which a real video may not be easy or even possible to procure, using analysis software with which the students are already familiar. We will…

  1. Making Artificial Seawater More Natural

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Marine fish will die if placed in fresh water and they cannot live in simple salt water. Instead, they need water that contains a mixture of different ingredients, as found in natural seawater. Conventional methods of making artificial seawater have shortcomings, because the water so achieved is only composed of mineral elements and lacks organic components similar to those in natural seawater.

  2. Twist1 activity thresholds define multiple functions in limb development.

    Science.gov (United States)

    Krawchuk, Dayana; Weiner, Shoshana J; Chen, You-Tzung; Lu, Benson C; Costantini, Frank; Behringer, Richard R; Laufer, Ed

    2010-11-01

    The basic helix-loop-helix transcription factor Twist1 is essential for normal limb development. Twist1(-/-) embryos die at midgestation. However, studies on early limb buds found that Twist1(-/-) mutant limb mesenchyme has an impaired response to FGF signaling from the apical ectodermal ridge, which disrupts the feedback loop between the mesenchyme and AER, and reduces and shifts anteriorly Shh expression in the zone of polarizing activity. We have combined Twist1 null, hypomorph and conditional alleles to generate a Twist1 allelic series that survives to birth. As Twist1 activity is reduced, limb skeletal defects progress from preaxial polydactyly to girdle reduction combined with hypoplasia, aplasia or mirror symmetry of all limb segments. With reduced Twist1 activity there is striking and progressive upregulation of ectopic Shh expression in the anterior of the limb, combined with an anterior shift in the posterior Shh domain, which is expressed at normal intensity, and loss of the posterior AER. Consequently limb outgrowth is initially impaired, before an ectopic anterior Shh domain expands the AER, promoting additional growth and repatterning. Reducing the dosage of FGF targets of the Etv gene family, which are known repressors of Shh expression in anterior limb mesenchyme, strongly enhances the anterior skeletal phenotype. Conversely this and other phenotypes are suppressed by reducing the dosage of the Twist1 antagonist Hand2. Our data support a model whereby multiple Twist1 activity thresholds contribute to early limb bud patterning, and suggest how particular combinations of skeletal defects result from differing amounts of Twist1 activity.

  3. Another Step Closer to Artificial Blood

    Science.gov (United States)

    ... news/fullstory_162357.html Another Step Closer to Artificial Blood Synthetic product could save lives on battlefield and ... 5, 2016 SATURDAY, Dec. 3, 2016 (HealthDay News) -- Artificial blood stored as a powder could one day revolutionize ...

  4. 21 CFR 886.3200 - Artificial eye.

    Science.gov (United States)

    2010-04-01

    ... OPHTHALMIC DEVICES Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a... inserted in a patient's eye socket anterior to an orbital implant, or the eviscerated eyeball, for...

  5. MRI findings of benign monomelic amyotrophy of lower limb.

    Science.gov (United States)

    Hamano, T; Mutoh, T; Hirayama, M; Ito, K; Kimura, M; Aita, T; Kiyosawa, K; Ohtaki, T; Kuriyama, M

    1999-06-01

    We report here magnetic resonance imaging (MRI) findings of two patients with benign monomelic amyotrophy of lower limb. Both subjects showed unilateral amyotrophy of the lower limb with a benign clinical course, and the affected muscles demonstrated neurogenic changes. On T1- and T2-weighted MRI, marked atrophy and increased signal intensity were found mainly in gastrocnemius and soleus muscles. Moreover, MRI examination also revealed that thigh muscles including semitendinosus, semimembranosus, and vastus intermedius and lateralis muscles were involved in one of the patients. We concluded that muscle MRI is very useful for detecting affected muscles, especially deep skeletal muscles in patients with benign monomelic amyotrophy of lower limb.

  6. Benign monomelic amyotrophy with proximal upper limb involvement: case report.

    Science.gov (United States)

    Neves, Marco Antonio Orsini; Freitas, Marcos R G de; Mello, Mariana Pimentel de; Dumard, Carlos Henrique; Freitas, Gabriel R de; Nascimento, Osvaldo J M

    2007-06-01

    Monomelic amyotrophy (MA) is a rare condition in which neurogenic amyotrophy is restricted to an upper or lower limb. Usually sporadic, it usually has an insidious onset with a mean evolution of 2 to 4 years following first clinical manifestations, which is, in turned, followed by stabilization. We report a case of 20-years-old man who presented slowly progressive amyotrophy associated with proximal paresis of the right upper limb, which was followed by clinical stabilization 4 years later. Eletroneuromyography revealed denervation along with myofasciculations in various muscle groups of the right upper limb. We call attention to this rare location of MA, as well as describe some theories concerning its pathophysiology .

  7. Twist1 activity thresholds define multiple functions in limb development

    OpenAIRE

    Krawchuk, Dayana; Weiner, Shoshana J; Chen, You-Tzung; Lu, Benson; Costantini, Frank; Behringer, Richard R.; Laufer, Ed

    2010-01-01

    The basic helix-loop-helix transcription factor Twist1 is essential for normal limb development. Twist1−/− embryos die at midgestation. However, studies on early limb buds found that Twist1−/− mutant limb mesenchyme has an impaired response to FGF signaling from the apical ectodermal ridge, which disrupts the feedback loop between the mesenchyme and AER, and reduces and shifts anteriorly Shh expression in the zone of polarizing activity. We have combined Twist1 null, hypomorph and conditional...

  8. Introduction to Concepts in Artificial Neural Networks

    Science.gov (United States)

    Niebur, Dagmar

    1995-01-01

    This introduction to artificial neural networks summarizes some basic concepts of computational neuroscience and the resulting models of artificial neurons. The terminology of biological and artificial neurons, biological and machine learning and neural processing is introduced. The concepts of supervised and unsupervised learning are explained with examples from the power system area. Finally, a taxonomy of different types of neurons and different classes of artificial neural networks is presented.

  9. Topological Optimization of Artificial Microstructure Strategies

    Science.gov (United States)

    2015-04-02

    Topographic Optimization Through Artificial Microstructure Strategies During this project as part of DARPA MCMA we aimed to develop and demonstrate...Topographic Optimization Through Artificial Microstructure Strategies Report Title During this project as part of DARPA MCMA we aimed to develop and...Artificial Microstructure Strategies (Yale and Johns Hopkins) During DARPA MCMA we aimed to develop and demonstrate a 3D microstructural

  10. Artificial Intelligence and Its Importance in Education.

    Science.gov (United States)

    Tilmann, Martha J.

    Artificial intelligence, or the study of ideas that enable computers to be intelligent, is discussed in terms of what it is, what it has done, what it can do, and how it may affect the teaching of tomorrow. An extensive overview of artificial intelligence examines its goals and applications and types of artificial intelligence including (1) expert…

  11. Lengthening of replanted or revascularized lower limbs: is length discrepancy a contraindication for limb salvage?

    Science.gov (United States)

    Parmaksizoglu, Fatih; Beyzadeoglu, Tahsin

    2002-08-01

    Some replantation cases require substantial bone shortening for primary closure. Leg-length discrepancy can be restored by lengthening of the replanted or revascularized extremities. Between 1991 and 2000, four patients with four total and two subtotal below-knee amputations had replantation or revascularization for their severely damaged extremities. All of them had extensive debridement, vascular repair, bone shortening and nerve repair for sensibility of their soles. One of the replanted extremities failed and had to undergo below-knee amputation because of sepsis. No other infection or vascular complications were encountered following the replantations or revascularizations. After bony consolidation, four legs were lengthened; for elimination of length discrepancy in three cases, and for obtaining balanced body proportion in one case in which the other leg was also amputated. In all procedures, a unilateral dynamic axial external fixator was used. The lengthening was performed from the proximal tibial metaphysis, with a subperiosteal osteotomy. Evaluation of injury according to the Mangled Extremity Severity Score (MESS) would encourage the surgeon to avoid salvage surgery with a shortened extremity, because of the required debridement of soft tissue and bone. These authors think the amount of limb shortening is not a major criterion in evaluating a traumatic total or subtotal below-knee amputation for salvage replantation or revascularization. A knee that has stable joint motion and the possibility of preservation of sensibility of the sole broadens the scope of indications for limb salvage, even with deliberate shortening that can be restored by lengthening; length discrepancy is not a contraindication for limb salvage.

  12. TES/Aura L1B Spectra Limb V002

    Data.gov (United States)

    National Aeronautics and Space Administration — The L1B Limb granule consists of radiometrically calibrated spectra & associated NESR, observed at 0.025 cm-1 resolution for an entire Global Survey &...

  13. When a Parent Loses a Limb: Helping Children Cope

    Science.gov (United States)

    ... Things to Remember Limb loss is not a punishment. However, if it was the result of an accident, you may want to talk about safety issues with the child at an appropriate time. The child will not “ ...

  14. Pain Management in Four-Limb Amputation: A Case Report.

    Science.gov (United States)

    Warner, Nafisseh S; Warner, Matthew A; Moeschler, Susan M; Hoelzer, Bryan C

    2015-09-01

    Acute pain following amputation can be challenging to treat due to multiple underlying mechanisms and variable clinical responses to treatment. Furthermore, poorly controlled preoperative pain is a risk factor for developing chronic pain. Evidence suggests that epidural analgesia and peripheral nerve blockade may decrease the severity of residual limb pain and the prevalence of phantom pain after lower extremity amputation. We present the perioperative analgesic management of a patient with gangrene of the bilateral upper and lower extremities as a result of septic shock and prolonged vasopressor administration who underwent four-limb amputation in a single procedure. A multimodal analgesic regimen was utilized, including titration of preoperative opioid and neuropathic pain agents, perioperative intravenous, epidural and peripheral nerve catheter infusions, and postoperative oral medication titration. More than 8 months postoperatively, the patient has satisfactory pain control with no evidence for phantom limb pain. To our knowledge, there have been no publications to date concerning analgesic regimens in four-limb amputation.

  15. Endoscopic release of limb constriction rings in utero.

    Science.gov (United States)

    Ronderos-Dumit, D; Briceño, F; Navarro, H; Sanchez, N

    2006-01-01

    Amniotic band syndrome is a sporadic condition that may result in constriction bands, amputation and multiple craniofacial, visceral and body wall defects. It occurs in 1/1,200 to 1/15,000 live births. Most cases present with multiple congenital anomalies that are incompatible with life. A small group of fetuses shows isolated limb constrictions that may cause severe limb dysfunction or limb amputation if left untreated. Successful in utero surgical lyses of constriction rings have been reported. We report a case of constriction amniotic bands involving both legs and compromising blood flow to the distal extremity. The constriction ring was successfully released by a minimally invasive endoscopic surgical technique avoiding severe limb dysfunction or foot amputation.

  16. Improved decoding of limb-state feedback from natural sensors.

    Science.gov (United States)

    Wagenaar, J B; Ventura, V; Weber, D J

    2009-01-01

    Limb state feedback is of great importance for achieving stable and adaptive control of FES neuroprostheses. A natural way to determine limb state is to measure and decode the activity of primary afferent neurons in the limb. The feasibility of doing so has been demonstrated by [1] and [2]. Despite positive results, some drawbacks in these works are associated with the application of reverse regression techniques for decoding the afferent neuronal signals. Decoding methods that are based on direct regression are now favored over reverse regression for decoding neural responses in higher regions in the central nervous system [3]. In this paper, we apply a direct regression approach to decode the movement of the hind limb of a cat from a population of primary afferent neurons. We show that this approach is more principled, more efficient, and more generalizable than reverse regression.

  17. [Tests of hand functionality in upper limb amputation with prosthesis].

    Science.gov (United States)

    Bazzini, G; Orlandini, D; Moscato, T A; Nicita, D; Panigazzi, M

    2007-01-01

    The need for standardized instruments for clinical measurements has become pressing in the fields of occupational rehabilitation and ergonomics. This is particularly the case for instruments that allow a quantitative evaluation of upper limb function, and especially hand function in patients who have undergone an amputation and then application of an upper limb prosthesis. This study presents a review of the main tests used to evaluate hand function, with a critical analysis of their use in subjects with an upper limb prosthesis. The tests are divided into: tests to evaluate strength, tests to evaluate co-ordination and dexterity, tests of global or overall function, and tests proposed specifically for subjects with an upper limb prosthesis. Of the various tests presented, the authors give their preference to the Bimanual Functional Assessment, Abilhand and/or the ADL Questionnaire, because of the practical usefulness, clinimetric features, simplicity and ease of administration of these tests.

  18. Review: Quality of life in lower limb peripheral vascular surgery

    NARCIS (Netherlands)

    Donker, J.M.; de Vries, Jolanda; Ho, G.H.; Bastos Gonçalves, F.; Hoeks, S.E.; Verhagen, H.J.M.; van der Laan, L.

    2015-01-01

    Purpose Vascular intervention studies generally consider patency and limb salvage as primary outcomes. However, quality of life is increasingly considered an important patient-oriented outcome measurement of vascular interventions. Existing literature was analyzed to determine the effect of differen

  19. Positional identity of adult stem cells in salamander limb regeneration.

    Science.gov (United States)

    Kumar, Anoop; Gates, Phillip B; Brockes, Jeremy P

    2007-01-01

    Limb regeneration in larval and adult salamanders proceeds from a mound of mesenchymal stem cells called the limb blastema. The blastema gives rise just to those structures distal to its level of origin, and this property of positional identity is reset to more proximal values by treatment with retinoic acid. We have identified a cell surface protein, called Prod1/CD59, which appears to be a determinant of proximodistal identity. Prod1 is expressed in an exponential gradient in an adult limb as determined by detection of both mRNA and immunoreactive protein. Prod1 protein is up-regulated after treatment of distal blastemas with RA and this is particularly marked in cells of the dermis. These cells have previously been implicated in pattern formation during limb regeneration.

  20. Left and right hand recognition in upper limb amputees.

    Science.gov (United States)

    Nico, Daniele; Daprati, Elena; Rigal, François; Parsons, Lawrence; Sirigu, Angela

    2004-01-01

    Previous research suggests a close similarity in brain activity between mental simulation of a movement and its real counterpart. To explore this similarity, we aimed to assess whether imagery is affected by the loss of a limb or of its motor skills. We examined the performance of 16 adult, upper limb amputees (and age-matched controls) in a left/right hand judgement task that implicitly requires motor imagery. The experimental group included subjects who had suffered the amputation of the dominant or the non-dominant limb. Although responding well above chance, amputees as a group were slower and less accurate than controls. Nevertheless, their response pattern was similar to that of controls, namely slower response times and more errors for stimuli depicting hands in unnatural orientations, i.e. postures difficult to reach with a real movement. Interestingly, for all stimuli, amputees' performance was strongly affected by the side of limb loss: subjects who underwent amputation of their preferred limb made more errors and required greater latencies to respond as compared with amputees of the non-dominant limb. In a further analysis we observed that the habit of wearing an aesthetic prosthesis significantly interfered with the ability to judge the corresponding hand. Our data lead to three main conclusions: (i) loss of a single limb per se does not prevent motor imagery but it significantly enhances its difficulty; (ii) these subjects apparently perform the hand recognition task using a strategy in which they initially mentally simulate movements of their dominant limb; (iii) wearing a prosthesis, devoid of any motor function, seems to interfere with motor imagery, consistent with the view that only 'tools' can be incorporated in a dynamic body schema.

  1. Benign monomelic amyotrophy with proximal upper limb involvement: case report

    OpenAIRE

    Neves,Marco Antonio Orsini; Marcos R. G.de Freitas; Mello,Mariana Pimentel; Dumard,Carlos Henrique; Gabriel R. de Freitas; Nascimento, Osvaldo J.M.

    2007-01-01

    Monomelic amyotrophy (MA) is a rare condition in which neurogenic amyotrophy is restricted to an upper or lower limb. Usually sporadic, it usually has an insidious onset with a mean evolution of 2 to 4 years following first clinical manifestations, which is, in turned, followed by stabilization. We report a case of 20-years-old man who presented slowly progressive amyotrophy associated with proximal paresis of the right upper limb, which was followed by clinical stabilization 4 years later. E...

  2. Pelvic and hind limb musculature of Staurikosaurus pricei (Dinosauria: Saurischia)

    OpenAIRE

    Grillo,Orlando N.; SERGIO A.K. AZEVEDO

    2011-01-01

    The study of pelvic and hind limb bones and muscles in basal dinosaurs is important for understanding the early evolution of bipedal locomotion in the group. The use of data from both extant and extinct taxa placed into a phylogenetic context allowed to make well-supported inferences concerning most of the hind limb musculature of the basal saurischian Staurikosaurus pricei Colbert, 1970 (Santa Maria Formation, Late Triassic of Rio Grande do Sul, Brazil). Two large concavities in the lateral ...

  3. Autosomal recessive limb girdle myasthenia in two sisters.

    Directory of Open Access Journals (Sweden)

    Shankar A

    2002-10-01

    Full Text Available Limb girdle myasthenic syndromes are rare genetic disorders described under the broad heterogeneous group known as congenital myasthenic syndromes and present with mixed features of myasthenia and myopathy. The familial limb girdle myasthenia has been described as one with selective weakness of pectoral and pelvic girdles, showing a positive response to edrophonium chloride. A report of two sisters affected by this disorder is presented.

  4. Image Processing for Planetary Limb/Terminator Extraction

    Science.gov (United States)

    Udomkesmalee, S.; Zhu, D. Q.; Chu, C. -C.

    1995-01-01

    A novel image segmentation technique for extracting limb and terminator of planetary bodies is proposed. Conventional edge- based histogramming approaches are used to trace object boundaries. The limb and terminator bifurcation is achieved by locating the harmonized segment in the two equations representing the 2-D parameterized boundary curve. Real planetary images from Voyager 1 and 2 served as representative test cases to verify the proposed methodology.

  5. Idiopathic unilateral lower limb gangrene in a neonate

    Directory of Open Access Journals (Sweden)

    Jagjit Singh

    2011-01-01

    Full Text Available We are reporting a very unusual case of unilateral lower limb gangrene in 12 days neonate, who was brought to us with bluish discoloration of left foot with gangrene of toes. A negative sepsis screen, normal Doppler study, normal magnetic resonance angiography and absence of evidence of hypercoagulable state prompted us to make the diagnosis of idiopathic unilateral lower limb gangrene in this newborn. Because of the rarity we are reporting this case with vide review of literature.

  6. Limb versus Speech Motor Control: A Conceptual Review

    OpenAIRE

    Grimme, Britta; Fuchs, Susanne; Perrier, Pascal; Schöner, Gregor

    2011-01-01

    International audience; This paper presents a comparative conceptual review of speech and limb motor control. Speech is essentially cognitive in nature and constrained by the rules of language, while limb movement is often oriented to physical objects. We discuss the issue of intrinsic vs. extrinsic variables underlying the representations of motor goals as well as whether motor goals specify terminal postures or entire trajectories. Timing and coordination is recognized as an area of strong ...

  7. Lower limb deficient children in the Netherlands: epidemiological aspects

    OpenAIRE

    Rijnders, LJM; Boonstra, AM; Groothoff, JW; Cornel, MC; Eisma, WH

    2000-01-01

    information on the characteristics of children with limb deficiencies and amputations in the Netherlands is largely lacking. The present study aimed to collect data about the prevalence of congenital deficiencies, the ratio of congenital to acquired limb deficiencies, types of lower leg deficiency or amputation and male/female ratios. Data were obtained from a regional birth defects registry for the northern parr. of the Netherlands (EUROCAT-NNL) and from a national survey, inclusion criteria...

  8. Economic reasoning and artificial intelligence.

    Science.gov (United States)

    Parkes, David C; Wellman, Michael P

    2015-07-17

    The field of artificial intelligence (AI) strives to build rational agents capable of perceiving the world around them and taking actions to advance specified goals. Put another way, AI researchers aim to construct a synthetic homo economicus, the mythical perfectly rational agent of neoclassical economics. We review progress toward creating this new species of machine, machina economicus, and discuss some challenges in designing AIs that can reason effectively in economic contexts. Supposing that AI succeeds in this quest, or at least comes close enough that it is useful to think about AIs in rationalistic terms, we ask how to design the rules of interaction in multi-agent systems that come to represent an economy of AIs. Theories of normative design from economics may prove more relevant for artificial agents than human agents, with AIs that better respect idealized assumptions of rationality than people, interacting through novel rules and incentive systems quite distinct from those tailored for people.

  9. Tadpole-like artificial micromotor

    Science.gov (United States)

    Liu, Limei; Liu, Mei; Su, Yajun; Dong, Yonggang; Zhou, Wei; Zhang, Lina; Zhang, Hui; Dong, Bin; Chi, Lifeng

    2015-01-01

    We describe a polymer-based artificial tadpole-like micromotor, which is fabricated through the electrospinning technique. By incorporating functional materials onto its surface or within its body, the resulting tadpole-like micromotor can not only move autonomously in an aqueous solution with a flexible tail, but also exhibit thermo- and magnetic responsive properties.We describe a polymer-based artificial tadpole-like micromotor, which is fabricated through the electrospinning technique. By incorporating functional materials onto its surface or within its body, the resulting tadpole-like micromotor can not only move autonomously in an aqueous solution with a flexible tail, but also exhibit thermo- and magnetic responsive properties. Electronic supplementary information (ESI) available: Experimental section, Fig. S1-S3 and Video S1-S4. See DOI: 10.1039/c4nr06621a

  10. Torsional Carbon Nanotube Artificial Muscles

    Science.gov (United States)

    Foroughi, Javad; Spinks, Geoffrey M.; Wallace, Gordon G.; Oh, Jiyoung; Kozlov, Mikhail E.; Fang, Shaoli; Mirfakhrai, Tissaphern; Madden, John D. W.; Shin, Min Kyoon; Kim, Seon Jeong; Baughman, Ray H.

    2011-10-01

    Rotary motors of conventional design can be rather complex and are therefore difficult to miniaturize; previous carbon nanotube artificial muscles provide contraction and bending, but not rotation. We show that an electrolyte-filled twist-spun carbon nanotube yarn, much thinner than a human hair, functions as a torsional artificial muscle in a simple three-electrode electrochemical system, providing a reversible 15,000° rotation and 590 revolutions per minute. A hydrostatic actuation mechanism, as seen in muscular hydrostats in nature, explains the simultaneous occurrence of lengthwise contraction and torsional rotation during the yarn volume increase caused by electrochemical double-layer charge injection. The use of a torsional yarn muscle as a mixer for a fluidic chip is demonstrated.

  11. Artificial intelligence and computer vision

    CERN Document Server

    Li, Yujie

    2017-01-01

    This edited book presents essential findings in the research fields of artificial intelligence and computer vision, with a primary focus on new research ideas and results for mathematical problems involved in computer vision systems. The book provides an international forum for researchers to summarize the most recent developments and ideas in the field, with a special emphasis on the technical and observational results obtained in the past few years.

  12. Artificial color perception using microwaves

    CERN Document Server

    Choudhury, Debesh

    2013-01-01

    We report the feasibility of artificial color perception under microwave illumination using a standard microwave source and an antenna. We have sensed transmitted microwave power through color objects and have distinguished the colors by analyzing the sensed transmitted power. Experiments are carried out using a Gunn diode as the microwave source, some colored liquids as the objects and a microwave diode as the detector. Results are presented which open up an unusual but new way of perceiving colors using microwaves.

  13. Automated Scheduling Via Artificial Intelligence

    Science.gov (United States)

    Biefeld, Eric W.; Cooper, Lynne P.

    1991-01-01

    Artificial-intelligence software that automates scheduling developed in Operations Mission Planner (OMP) research project. Software used in both generation of new schedules and modification of existing schedules in view of changes in tasks and/or available resources. Approach based on iterative refinement. Although project focused upon scheduling of operations of scientific instruments and other equipment aboard spacecraft, also applicable to such terrestrial problems as scheduling production in factory.

  14. Artificial color perception using microwaves

    OpenAIRE

    Choudhury, Debesh; Caulfield, H. John

    2013-01-01

    We report the feasibility of artificial color perception under microwave illumination using a standard microwave source and an antenna. We have sensed transmitted microwave power through color objects and have distinguished the colors by analyzing the sensed transmitted power. Experiments are carried out using a Gunn diode as the microwave source, some colored liquids as the objects and a microwave diode as the detector. Results are presented which open up an unusual but new way of perceiving...

  15. A Definition of Artificial Intelligence

    OpenAIRE

    2012-01-01

    In this paper we offer a formal definition of Artificial Intelligence and this directly gives us an algorithm for construction of this object. Really, this algorithm is useless due to the combinatory explosion. The main innovation in our definition is that it does not include the knowledge as a part of the intelligence. So according to our definition a newly born baby also is an Intellect. Here we differs with Turing's definition which suggests that an Intellect is a person with knowledge gai...

  16. Towards photovoltaic powered artificial retina

    OpenAIRE

    2011-01-01

    The aim of this article is to provide an overview of current and future concepts in the field of retinal prostheses, and is focused on the power supply based on solar energy conversion; we introduce the possibility of using PV minimodules as power supply for a new concept of retinal prostheses: Photovoltaic Powered Artificial Retina (PVAR). Main characteristics of these PV modules are presented showing its potential for this application. Peer Reviewed

  17. Artificial Sweeteners versus Natural Sweeteners

    OpenAIRE

    Neacsu, N.A.; Madar, A.

    2014-01-01

    Carbohydrates are an important dietary nutrient which is mostly used to supply energy to the body, as well as a carbon source for synthesis of other needed chemicals. In addition, mono- and disaccharides are craved because of their sweetness. We present different types of sweeteners, which are the basic contents of foods which we consume every day and are demonstrated the positive and negative effects of natural and artificial sweeteners.

  18. Artificial Sweeteners versus Natural Sweeteners

    Directory of Open Access Journals (Sweden)

    Neacsu, N.A.

    2014-06-01

    Full Text Available Carbohydrates are an important dietary nutrient which is mostly used to supply energy to the body, as well as a carbon source for synthesis of other needed chemicals. In addition, mono- and disaccharides are craved because of their sweetness. We present different types of sweeteners, which are the basic contents of foods which we consume every day and are demonstrated the positive and negative effects of natural and artificial sweeteners.

  19. Bioengineering of Artificial Lymphoid Organs

    OpenAIRE

    Nosenko, M. A.; Drutskaya, M. S; M. M. Moisenovich; Nedospasov, S A

    2016-01-01

    This review addresses the issue of bioengineering of artificial lymphoid organs.Progress in this field may help to better understand the nature of the structure-function relations that exist in immune organs. Artifical lymphoid organs may also be advantageous in the therapy or correction of immunodefficiencies, autoimmune diseases, and cancer. The structural organization, development, and function of lymphoid tissue are analyzed with a focus on the role of intercellular contacts and on the cy...

  20. Lower limb strength in sports-active transtibial amputees.

    Science.gov (United States)

    Nolan, Lee

    2009-09-01

    The aim of this study was to compare hip strength in sports-active transtibial (TT) amputees, sedentary TT amputees and sports-active non-amputees. Three 'active' (exercising recreationally at least three times per week) TT amputees, four 'inactive' or sedentary TT amputees and nine 'active' able-bodied persons (AB) underwent concentric and eccentric hip flexion and extension strength testing on both limbs on an isokinetic dynamometer at 60 and 120 degrees /s. Little strength asymmetry was noted between the limbs of the active TT amputees (8% and 14% at 60 and 120 degrees /s, respectively), their residual limb being slightly stronger. Inactive TT amputees demonstrated up to 49% strength asymmetry, their intact limb being the stronger. Active TT amputees demonstrated greater peak hip torques (Nm/kg) for all conditions and speeds compared to inactive TT amputees. Peak hip torques (Nm/kg), were greater in the active TT amputees' residual limb compared to AB. While inactive TT amputees and AB had similar flexion/extension ratios, active TT amputees exhibited a lower ratio indicating overdeveloped hip extensors with respect to their hip flexors. It is not known whether this is due to the demands of sport or exercise with a prosthetic limb, or remaining residual thigh atrophy.

  1. The role of Hox genes during vertebrate limb development.

    Science.gov (United States)

    Zakany, Jozsef; Duboule, Denis

    2007-08-01

    The potential role of Hox genes during vertebrate limb development was brought into focus by gene expression analyses in mice (P Dolle, JC Izpisua-Belmonte, H Falkenstein, A Renucci, D Duboule, Nature 1989, 342:767-772), at a time when limb growth and patterning were thought to depend upon two distinct and rather independent systems of coordinates; one for the anterior-to-posterior axis and the other for the proximal-to-distal axis (see D Duboule, P Dolle, EMBO J 1989, 8:1497-1505). Over the past years, the function and regulation of these genes have been addressed using both gain-of-function and loss-of-function approaches in chick and mice. The use of multiple mutations either in cis-configuration in trans-configuration or in cis/trans configurations, has confirmed that Hox genes are essential for proper limb development, where they participate in both the growth and organization of the structures. Even though their molecular mechanisms of action remain somewhat elusive, the results of these extensive genetic analyses confirm that, during the development of the limbs, the various axes cannot be considered in isolation from each other and that a more holistic view of limb development should prevail over a simple cartesian, chess grid-like approach of these complex structures. With this in mind, the functional input of Hox genes during limb growth and development can now be re-assessed.

  2. Limb proportions show developmental plasticity in response to embryo movement

    Science.gov (United States)

    Pollard, A. S.; Charlton, B. G.; Hutchinson, J. R.; Gustafsson, T.; McGonnell, I. M.; Timmons, J. A.; Pitsillides, A. A.

    2017-01-01

    Animals have evolved limb proportions adapted to different environments, but it is not yet clear to what extent these proportions are directly influenced by the environment during prenatal development. The developing skeleton experiences mechanical loading resulting from embryo movement. We tested the hypothesis that environmentally-induced changes in prenatal movement influence embryonic limb growth to alter proportions. We show that incubation temperature influences motility and limb bone growth in West African Dwarf crocodiles, producing altered limb proportions which may, influence post-hatching performance. Pharmacological immobilisation of embryonic chickens revealed that altered motility, independent of temperature, may underpin this growth regulation. Use of the chick also allowed us to merge histological, immunochemical and cell proliferation labelling studies to evaluate changes in growth plate organisation, and unbiased array profiling to identify specific cellular and transcriptional targets of embryo movement. This disclosed that movement alters limb proportions and regulates chondrocyte proliferation in only specific growth plates. This selective targeting is related to intrinsic mTOR (mechanistic target of rapamycin) pathway activity in individual growth plates. Our findings provide new insights into how environmental factors can be integrated to influence cellular activity in growing bones and ultimately gross limb morphology, to generate phenotypic variation during prenatal development. PMID:28165010

  3. LIMB Demonstration Project Extension and Coolside Demonstration. [Final report

    Energy Technology Data Exchange (ETDEWEB)

    Goots, T.R.; DePero, M.J.; Nolan, P.S.

    1992-11-10

    This report presents results from the limestone Injection Multistage Burner (LIMB) Demonstration Project Extension. LIMB is a furnace sorbent injection technology designed for the reduction of sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) emissions from coal-fired utility boilers. The testing was conducted on the 105 Mwe, coal-fired, Unit 4 boiler at Ohio Edison`s Edgewater Station in Lorain, Ohio. In addition to the LIMB Extension activities, the overall project included demonstration of the Coolside process for S0{sub 2} removal for which a separate report has been issued. The primary purpose of the DOE LIMB Extension testing, was to demonstrate the generic applicability of LIMB technology. The program sought to characterize the S0{sub 2} emissions that result when various calcium-based sorbents are injected into the furnace, while burning coals having sulfur content ranging from 1.6 to 3.8 weight percent. The four sorbents used included calcitic limestone, dolomitic hydrated lime, calcitic hydrated lime, and calcitic hydrated lime with a small amount of added calcium lignosulfonate. The results include those obtained for the various coal/sorbent combinations and the effects of the LIMB process on boiler and plant operations.

  4. Beller Lecture: Artificial Ferroic Systems

    Science.gov (United States)

    Heyderman, Laura

    In artificial ferroic systems, novel functionality is engineered through the combination of structured ferroic materials and the control of the interactions between the different components. I will present two classes of these systems, beginning with hybrid mesoscopic structures incorporating two different ferromagnetic layers whose static and dynamic behaviour result from the mutual imprint of the magnetic domain configurations. Here we have demonstrated a new vortex core reversal mechanism, which occurs when it is displaced across domain boundaries with a magnetic field. I will then describe our progress on artificial spin ice, consisting of arrays of dipolar-coupled nanomagnets arranged in frustrated geometries. We have employed photoemission electron microscopy to observe the behaviour of emergent magnetic monopoles in an array of nanomagnets placed on the kagome lattice. We have also created artificial spin ice with fluctuating magnetic moments and observed the evolution of magnetic configurations with time. This has provided a means to study relaxation processes with a controlled route to the lowest-energy state. Recently, we have demonstrated with muon spin relaxation that these magnetic metamaterials can support thermodynamic phase transitions, and future directions include the incorporation of novel magnetic materials such as ultrathin magnetic films, the investigation of 3D structures, as well as the implementation of x-ray resonant magnetic scattering to study magnetic correlations in smaller nanomagnets and at faster timescales

  5. Miniature curved artificial compound eyes.

    Science.gov (United States)

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-04

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories.

  6. Artificial life: The coming evolution

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J.D. (Los Alamos National Lab., NM (USA) Santa Fe Inst., NM (USA)); Belin, A.d' A. (Shute, Mihaly, and Weinberger, Santa Fe, NM (USA))

    1990-01-01

    Within fifty to a hundred years a new class of organisms is likely to emerge. These organisms will be artificial in the sense that they will originally be designed by humans. However, they will reproduce, and will evolve into something other than their initial form; they will be alive'' under any reasonable definition of the word. These organisms will evolve in a fundamentally different manner than contemporary biological organisms, since their reproduction will be under at least partial conscious control, giving it a Lamarckian component. The pace of evolutionary change consequently will be extremely rapid. The advent of artificial life will be the most significant historical event since the emergence of human beings. The impact on humanity and the biosphere could be enormous, larger than the industrial revolution, nuclear weapons, or environmental pollution. We must take steps now to shape the emergence of artificial organisms; they have potential to be either the ugliest terrestrial disaster, or the most beautiful creation of humanity. 22 refs., 3 figs.

  7. Pleiotropic patterning response to activation of Shh signaling in the limb apical ectodermal ridge.

    Science.gov (United States)

    Wang, Chi-Kuang Leo; Tsugane, Mizuyo H; Scranton, Victoria; Kosher, Robert A; Pierro, Louis J; Upholt, William B; Dealy, Caroline N

    2011-05-01

    Sonic hedgehog (Shh) signaling in the limb plays a central role in coordination of limb patterning and outgrowth. Shh expression in the limb is limited to the cells of the zone of polarizing activity (ZPA), located in posterior limb bud mesoderm. Shh is not expressed by limb ectoderm or apical ectodermal ridge (AER), but recent studies suggest a role for AER-Shh signaling in limb patterning. Here, we have examined the effects of activation of Shh signaling in the AER. We find that targeted expression of Shh in the AER activates constitutive Shh signaling throughout the AER and subjacent limb mesoderm, and causes a range of limb patterning defects with progressive severity from mild polydactyly, to polysyndactyly with proximal defects, to severe oligodactyly with phocomelia and partial limb ventralization. Our studies emphasize the importance of control of the timing, level and location of Shh pathway signaling for limb anterior-posterior, proximal-distal, and dorsal-ventral patterning.

  8. Artificial insemination history: hurdles and milestones.

    Science.gov (United States)

    Ombelet, W; Van Robays, J

    2015-01-01

    Artificial insemination with homologous (AIH) or donor semen (AID) is nowadays a very popular treatment procedure used for many subfertile women worldwide. The rationale behind artificial insemination is to increase gamete density at the site of fertilisation. The sequence of events leading to today's common use of artificial insemination traces back to scientific studies and experimentation many centuries ago. Modern techniques used in human artificial insemination programmes are mostly adapted from the work on cattle by dairy farmers wishing to improve milk production by using artificial insemination with sperm of selected bulls with well chosen genetic traits. The main reason for the renewed interest in artificial insemination in human was associated with the refinement of techniques for the preparation of washed motile spermatozoa in the early years of IVF. The history of artificial insemination is reviewed with particular interest to the most important hurdles and milestones.

  9. Modified Vertical Rectus Abdominis Musculocutaneous Flap for Limb Salvage Procedures in Proximal Lower Limb Musculoskeletal Sarcomas

    Directory of Open Access Journals (Sweden)

    Haitham H. Khalil

    2008-01-01

    Full Text Available Introduction and aim. Management of complicated wounds after tumor extipiration of pelvic and proximal lower limb musculoskeletal sarcoma represents an essential component in the outcome of these patients. The authors present modified vertical rectus abdominis musculocutaneous (VRAM flap techniques to reconstruct extensive defects after debridment of these complicated wounds. Material and Methods. Over a period of 4 years (2002–2005, 5 men and 2 women were managed. Median age was 21 years (range 15–49. The patients were managed for complicated lower trunk, groin, and upper thigh wounds after resection of three pelvic chondrosarcomas as well as two pelvic and two proximal femur osteosarcomas. The modifications included a VRAM flap with lateral and tongue-like extension design of the skin paddle (5 cases or a delayed extended VRAM flap (2 cases. Results. All flaps showed complete survival and healing with no ischemic events providing stable coverage. All patients were ambulant with good limb functions in terms of walking and gait after adequate rehabilitation, 2 needed support with crutches. Conclusion. The modified VRAM flaps offer reliable reconstructive tools for coverage of complex groin and thigh defects by providing larger well-vascularized soft tissue with acceptable donor site.

  10. Trade-offs in relative limb length among Peruvian children: extending the thrifty phenotype hypothesis to limb proportions.

    Directory of Open Access Journals (Sweden)

    Emma Pomeroy

    Full Text Available BACKGROUND AND METHODS: Both the concept of 'brain-sparing' growth and associations between relative lower limb length, childhood environment and adult disease risk are well established. Furthermore, tibia length is suggested to be particularly plastic under conditions of environmental stress. The mechanisms responsible are uncertain, but three hypotheses may be relevant. The 'thrifty phenotype' assumes that some components of growth are selectively sacrificed to preserve more critical outcomes, like the brain. The 'distal blood flow' hypothesis assumes that blood nutrients decline with distance from the heart, and hence may affect limbs in relation to basic body geometry. Temperature adaptation predicts a gradient of decreased size along the limbs reflecting decreasing tissue temperature/blood flow. We examined these questions by comparing the size of body segments among Peruvian children born and raised in differentially stressful environments. In a cross-sectional sample of children aged 6 months to 14 years (n = 447 we measured head circumference, head-trunk height, total upper and lower limb lengths, and zeugopod (ulna and tibia and autopod (hand and foot lengths. RESULTS: Highland children (exposed to greater stress had significantly shorter limbs and zeugopod and autopod elements than lowland children, while differences in head-trunk height were smaller. Zeugopod elements appeared most sensitive to environmental conditions, as they were relatively shorter among highland children than their respective autopod elements. DISCUSSION: The results suggest that functional traits (hand, foot, and head may be partially protected at the expense of the tibia and ulna. The results do not fit the predictions of the distal blood flow and temperature adaptation models as explanations for relative limb segment growth under stress conditions. Rather, our data support the extension of the thrifty phenotype hypothesis to limb growth, and suggest that

  11. A Prosthesis to Train the Proprioceptive Capabilities of the Residual Limb of Military Personnel Recovering from Lower Limb Amputation

    Science.gov (United States)

    2012-09-01

    feedback from the ankle and foot poses challenge. To compensate for the lack of afferent feedback, amputees look down at the prosthesis to sense...10-1-0573 TITLE: A prosthesis to train the proprioceptive capabilities of the residual limb of military personnel recovering from lower limb...To) 1September2011-31August2012 4. TITLE AND SUBTITLE A Prosthesis to Train the Proprioceptive Capabilities of the 5a. CONTRACT NUMBER

  12. Walking like dinosaurs: chickens with artificial tails provide clues about non-avian theropod locomotion.

    Directory of Open Access Journals (Sweden)

    Bruno Grossi

    Full Text Available Birds still share many traits with their dinosaur ancestors, making them the best living group to reconstruct certain aspects of non-avian theropod biology. Bipedal, digitigrade locomotion and parasagittal hindlimb movement are some of those inherited traits. Living birds, however, maintain an unusually crouched hindlimb posture and locomotion powered by knee flexion, in contrast to the inferred primitive condition of non-avian theropods: more upright posture and limb movement powered by femur retraction. Such functional differences, which are associated with a gradual, anterior shift of the centre of mass in theropods along the bird line, make the use of extant birds to study non-avian theropod locomotion problematic. Here we show that, by experimentally manipulating the location of the centre of mass in living birds, it is possible to recreate limb posture and kinematics inferred for extinct bipedal dinosaurs. Chickens raised wearing artificial tails, and consequently with more posteriorly located centre of mass, showed a more vertical orientation of the femur during standing and increased femoral displacement during locomotion. Our results support the hypothesis that gradual changes in the location of the centre of mass resulted in more crouched hindlimb postures and a shift from hip-driven to knee-driven limb movements through theropod evolution. This study suggests that, through careful experimental manipulations during the growth phase of ontogeny, extant birds can potentially be used to gain important insights into previously unexplored aspects of bipedal non-avian theropod locomotion.

  13. Walking like dinosaurs: chickens with artificial tails provide clues about non-avian theropod locomotion.

    Science.gov (United States)

    Grossi, Bruno; Iriarte-Díaz, José; Larach, Omar; Canals, Mauricio; Vásquez, Rodrigo A

    2014-01-01

    Birds still share many traits with their dinosaur ancestors, making them the best living group to reconstruct certain aspects of non-avian theropod biology. Bipedal, digitigrade locomotion and parasagittal hindlimb movement are some of those inherited traits. Living birds, however, maintain an unusually crouched hindlimb posture and locomotion powered by knee flexion, in contrast to the inferred primitive condition of non-avian theropods: more upright posture and limb movement powered by femur retraction. Such functional differences, which are associated with a gradual, anterior shift of the centre of mass in theropods along the bird line, make the use of extant birds to study non-avian theropod locomotion problematic. Here we show that, by experimentally manipulating the location of the centre of mass in living birds, it is possible to recreate limb posture and kinematics inferred for extinct bipedal dinosaurs. Chickens raised wearing artificial tails, and consequently with more posteriorly located centre of mass, showed a more vertical orientation of the femur during standing and increased femoral displacement during locomotion. Our results support the hypothesis that gradual changes in the location of the centre of mass resulted in more crouched hindlimb postures and a shift from hip-driven to knee-driven limb movements through theropod evolution. This study suggests that, through careful experimental manipulations during the growth phase of ontogeny, extant birds can potentially be used to gain important insights into previously unexplored aspects of bipedal non-avian theropod locomotion.

  14. Bioimpedance profiling of the limbs: Update

    Science.gov (United States)

    Ward, L. C.; Essex, T.; Bartlett, M.; Kilbreath, S.; Brookes, D.

    2010-04-01

    Bioelectrical impedance spectroscopy (BIS) is now commonly used to assess breast cancer-related lymphoedema. Typically, the ratio of impedances of the two arms, determined at zero frequency (Z0), is used as a quantitative index of the presence of excess lymph. Measurement uses skin electrodes spanning the whole limb. However, lymphoedema may be highly localised and may involve changes other than simple fluid accumulation, e.g. increased fat and fibrosis, that also give rise to changes in impedance-related parameters such as capacitance. We have previously reported (13th ICEBI, Graz, 2007) a prototype mobile electrode probe that replaces the distal sense electrode which, when moved proximally along the arm, provides an impedance profile. We report here the further development of this technology to incorporate real-time measurement of impedance integrated with a digital measuring wheel. This allows exact synchronisation of impedance with position on the arm. A commercial BIS instrument (ImpediMed SFB7) was modified to collect impedance (R and Xc) data every msec and the mean impedance computed for each 10-mm slice. The apparent resistivity values for arm tissue were used to calculate slice volumes. These computed volumes were compared to equivalent slice volumes from perometry and DXA. The system is being further validated by correlating slice impedance parameters with lean tissue volume determined by pQCT (StraTec XCT 3000), for multiple positions along the arm. Ultimately, it is hoped that such measurements will not only allow localised tissue volume measurement but will also provide information of tissue composition in conditions such as lymphoedema.

  15. Fecundación Artificial

    Directory of Open Access Journals (Sweden)

    Ochoa. Fidel

    1939-10-01

    Full Text Available Por Fecundación artificial se entiende, la fecundación de una hembra sin el servicio directo del macho, es decir la introducción al aparato genital femenino, del esperma que se ha recogido por medios artificiales. Esta fecundación, practicada en debidas condiciones, tiene el mismo efecto de la fecundación natural, con las ventajas que veremos más adelante. La fecundación artificial permite explotar un reproductor a su máximum de capacidad, ya que se considera, para no hacer cálculos alegres, que un servicio de un caballo puede servir, diluido, por lo menos para cuatro yeguas, según los autores americanos, y para 10 a 15, según otros autores. El toro y el carnero pueden dar esperma suficiente en un servicio para fecundar de 10 a 12 hembras, según,los americanos, y según otros autores, hasta para 40. Los investigadores rusos han podido fecundar hasta 60 vacas con un solo servicio y han logrado con reproductores valiosos, fecundar 10.263 vacas por toro, a pesar de que éstos sólo han servido, durante un periodo de monta de sólo dos meses. Estos mismos han logrado fecundar artificialmente 2.733 ovejas con un solo carnero, y 1.403 con otro Los investigadores americanos han contado 22 servicios a un carnero vigoroso en un periodo de ocho horas, y durante este tiempo produjo esperma suficiente para haber fecundado 200 ovejas artificialmente. La fecundación artificial sirve para evitar la trasmisión de enfermedades que se contagian por el coito, tales como la durina, enfermedad ésta producida por un tripanosoma que por fortuna no existe entre nosotros. A las estaciones de monta llevan con frecuencia hembras afectadas de enfermedades como la vaginitis granulosa de la vaca, que se contagia al toro y de éste a otras hembras. Como el control sanitario de toda hembra llevada al servicio de un reproductor de estas estaciones de monta no siempre puede efectuarse por dificultades de distinta índole, mediante la fecundación artificial

  16. Major limb amputations: A tertiary hospital experience in northwestern Tanzania

    Directory of Open Access Journals (Sweden)

    Chalya Phillipo L

    2012-05-01

    Full Text Available Abstract Background Major limb amputation is reported to be a major but preventable public health problem that is associated with profound economic, social and psychological effects on the patient and family especially in developing countries where the prosthetic services are poor. The purpose of this study was to outline the patterns, indications and short term complications of major limb amputations and to compare our experience with that of other published data. Methods This was a descriptive cross-sectional study that was conducted at Bugando Medical Centre between March 2008 and February 2010. All patients who underwent major limb amputation were, after informed consent for the study, enrolled into the study. Data were collected using a pre-tested, coded questionnaire and analyzed using SPSS version 11.5 computer software. Results A total of 162 patients were entered into the study. Their ages ranged between 2–78 years (mean 28.30 ± 13.72 days. Males outnumbered females by a ratio of 2:1. The majority of patients (76.5% had primary or no formal education. One hundred and twelve (69.1% patients were unemployed. The most common indication for major limb amputation was diabetic foot complications in 41.9%, followed by trauma in 38.4% and vascular disease in 8.6% respectively. Lower limbs were involved in 86.4% of cases and upper limbs in 13.6% of cases giving a lower limb to upper limb ratio of 6.4:1 Below knee amputation was the most common procedure performed in 46.3%. There was no bilateral limb amputation. The most common additional procedures performed were wound debridement, secondary suture and skin grafting in 42.3%, 34.5% and 23.2% respectively. Two-stage operation was required in 45.4% of patients. Revision amputation rate was 29.6%. Post-operative complication rate was 33.3% and surgical site infection was the most common complication accounting for 21.0%. The mean length of hospital stay was 22.4 days and mortality

  17. Second-Generation Six-Limbed Experimental Robot

    Science.gov (United States)

    Kennedy, Brett; Okon, Avi; Aghazarian, Hrand; Robinson, Matthew; Garrett, Michael; Magnone, Lee

    2004-01-01

    The figure shows the LEMUR II - the second generation of the Limbed Excursion Mechanical Utility Robot (LEMUR), which was described in "Six-Legged Experimental Robot" (NPO-20897), NASA Tech Briefs, Vol. 25, No. 12 (December 2001), page 58. The LEMUR II incorporates a number of improvements, including new features, that extend its capabilities beyond those of its predecessor, which is now denoted the LEMUR I. To recapitulate: the LEMUR I was a six-limbed robot for demonstrating robotic capabilities for assembly, maintenance, and inspection. The LEMUR I was designed to be capable of walking autonomously along a truss structure toward a mechanical assembly at a prescribed location and to perform other operations. The LEMUR I was equipped with stereoscopic video cameras and image-data-processing circuitry for navigation and mechanical operations. It was also equipped with a wireless modem, through which it could be commanded remotely. Upon arrival at a mechanical assembly, the LEMUR I would perform simple mechanical operations with one or both of its front limbs. It could also transmit images to a host computer. Each of the six limbs of the LEMUR I was operated independently. Each of the four rear limbs had three degrees of freedom (DOFs), while each of the front two limbs had four DOFs. The front two limbs were designed to hold, operate, and/or be integrated with tools. The LEMUR I included an onboard computer equipped with an assortment of digital control circuits, digital input/output circuits, analog-to-digital converters for input, and digital-to-analog (D/A) converters for output. Feedback from optical encoders in the limb actuators was utilized for closed-loop microcomputer control of the positions and velocities of the actuators. The LEMUR II incorporates the following improvements over the LEMUR I: a) The drive trains for the joints of the LEMUR II are more sophisticated, providing greater torque and accuracy. b) The six limbs are arranged symmetrically about

  18. Synergistic control of forearm based on accelerometer data and artificial neural networks

    Directory of Open Access Journals (Sweden)

    B. Mijovic

    2008-05-01

    Full Text Available In the present study, we modeled a reaching task as a two-link mechanism. The upper arm and forearm motion trajectories during vertical arm movements were estimated from the measured angular accelerations with dual-axis accelerometers. A data set of reaching synergies from able-bodied individuals was used to train a radial basis function artificial neural network with upper arm/forearm tangential angular accelerations. The trained radial basis function artificial neural network for the specific movements predicted forearm motion from new upper arm trajectories with high correlation (mean, 0.9149-0.941. For all other movements, prediction was low (range, 0.0316-0.8302. Results suggest that the proposed algorithm is successful in generalization over similar motions and subjects. Such networks may be used as a high-level controller that could predict forearm kinematics from voluntary movements of the upper arm. This methodology is suitable for restoring the upper limb functions of individuals with motor disabilities of the forearm, but not of the upper arm. The developed control paradigm is applicable to upper-limb orthotic systems employing functional electrical stimulation. The proposed approach is of great significance particularly for humans with spinal cord injuries in a free-living environment. The implication of a measurement system with dual-axis accelerometers, developed for this study, is further seen in the evaluation of movement during the course of rehabilitation. For this purpose, training-related changes in synergies apparent from movement kinematics during rehabilitation would characterize the extent and the course of recovery. As such, a simple system using this methodology is of particular importance for stroke patients. The results underlie the important issue of upper-limb coordination.

  19. Functional analysis of limb transcriptional enhancers in the mouse.

    Science.gov (United States)

    Nolte, Mark J; Wang, Ying; Deng, Jian Min; Swinton, Paul G; Wei, Caimiao; Guindani, Michele; Schwartz, Robert J; Behringer, Richard R

    2014-01-01

    Transcriptional enhancers are genomic sequences bound by transcription factors that act together with basal transcriptional machinery to regulate gene transcription. Several high-throughput methods have generated large datasets of tissue-specific enhancer sequences with putative roles in developmental processes. However, few enhancers have been deleted from the genome to determine their roles in development. To understand the roles of two enhancers active in the mouse embryonic limb bud we deleted them from the genome. Although the genes regulated by these enhancers are unknown, they were selected because they were identified in a screen for putative limb bud-specific enhancers associated with p300, an acetyltransferase that participates in protein complexes that promote active transcription, and because the orthologous human enhancers (H1442 and H280) drive distinct lacZ expression patterns in limb buds of embryonic day (E) 11.5 transgenic mice. We show that the orthologous mouse sequences, M1442 and M280, regulate dynamic expression in the developing limb. Although significant transcriptional differences in enhancer-proximal genes in embryonic limb buds accompany the deletion of M1442 and M280 no gross limb malformations during embryonic development were observed, demonstrating that M1442 and M280 are not required for mouse limb development. However, M280 is required for the development and/or maintenance of body size; M280 mice are significantly smaller than controls. M280 also harbors an "ultraconserved" sequence that is identical between human, rat, and mouse. This is the first report of a phenotype resulting from the deletion of an ultraconserved element. These studies highlight the importance of determining enhancer regulatory function by experiments that manipulate them in situ and suggest that some of an enhancer's regulatory capacities may be developmentally tolerated rather than developmentally required.

  20. Artificial organic networks artificial intelligence based on carbon networks

    CERN Document Server

    Ponce-Espinosa, Hiram; Molina, Arturo

    2014-01-01

    This monograph describes the synthesis and use of biologically-inspired artificial hydrocarbon networks (AHNs) for approximation models associated with machine learning and a novel computational algorithm with which to exploit them. The reader is first introduced to various kinds of algorithms designed to deal with approximation problems and then, via some conventional ideas of organic chemistry, to the creation and characterization of artificial organic networks and AHNs in particular. The advantages of using organic networks are discussed with the rules to be followed to adapt the network to its objectives. Graph theory is used as the basis of the necessary formalism. Simulated and experimental examples of the use of fuzzy logic and genetic algorithms with organic neural networks are presented and a number of modeling problems suitable for treatment by AHNs are described: ·        approximation; ·        inference; ·        clustering; ·        control; ·        class...

  1. FPGA controlled artificial vascular system

    Directory of Open Access Journals (Sweden)

    Laqua D.

    2015-09-01

    Full Text Available Monitoring the oxygen saturation of an unborn child is an invasive procedure, so far. Transabdominal fetal pulse oximetry is a promising method under research, used to estimate the oxygen saturation of a fetus noninvasively. Due to the nature of the method, the fetal information needs to be extracted from a mixed signal. To properly evaluate signal processing algorithms, a phantom modeling fetal and maternal blood circuits and tissue layers is necessary. This paper presents an improved hardware concept for an artificial vascular system, utilizing an FPGA based CompactRIO System from National Instruments. The experimental model to simulate the maternal and fetal blood pressure curve consists of two identical hydraulic circuits. Each of these circuits consists of a pre-pressure system and an artificial vascular system. Pulse curves are generated by proportional valves, separating these two systems. The dilation of the fetal and maternal artificial vessels in tissue substitutes is measured by transmissive and reflective photoplethysmography. The measurement results from the pressure sensors and the transmissive optical sensors are visualized to show the functionality of the pulse generating systems. The trigger frequency for the maternal valve was set to 1 per second, the fetal valve was actuated at 0.7 per second for validation. The reflective curve, capturing pulsations of the fetal and maternal circuit, was obtained with a high power LED (905 nm as light source. The results show that the system generates pulse curves, similar to its physiological equivalent. Further, the acquired reflective optical signal is modulated by the alternating diameter of the tubes of both circuits, allowing for tests of signal processing algorithms.

  2. A neural tracking and motor control approach to improve rehabilitation of upper limb movements

    Directory of Open Access Journals (Sweden)

    Schmid Maurizio

    2008-02-01

    Full Text Available Abstract Background Restoration of upper limb movements in subjects recovering from stroke is an essential keystone in rehabilitative practices. Rehabilitation of arm movements, in fact, is usually a far more difficult one as compared to that of lower extremities. For these reasons, researchers are developing new methods and technologies so that the rehabilitative process could be more accurate, rapid and easily accepted by the patient. This paper introduces the proof of concept for a new non-invasive FES-assisted rehabilitation system for the upper limb, called smartFES (sFES, where the electrical stimulation is controlled by a biologically inspired neural inverse dynamics model, fed by the kinematic information associated with the execution of a planar goal-oriented movement. More specifically, this work details two steps of the proposed system: an ad hoc markerless motion analysis algorithm for the estimation of kinematics, and a neural controller that drives a synthetic arm. The vision of the entire system is to acquire kinematics from the analysis of video sequences during planar arm movements and to use it together with a neural inverse dynamics model able to provide the patient with the electrical stimulation patterns needed to perform the movement with the assisted limb. Methods The markerless motion tracking system aims at localizing and monitoring the arm movement by tracking its silhouette. It uses a specifically designed motion estimation method, that we named Neural Snakes, which predicts the arm contour deformation as a first step for a silhouette extraction algorithm. The starting and ending points of the arm movement feed an Artificial Neural Controller, enclosing the muscular Hill's model, which solves the inverse dynamics to obtain the FES patterns needed to move a simulated arm from the starting point to the desired point. Both position error with respect to the requested arm trajectory and comparison between curvature factors

  3. Formal Definition of Artificial Intelligence

    OpenAIRE

    Dobrev, Dimiter

    2005-01-01

    * This publication is partially supported by the KT-DigiCult-Bg project. A definition of Artificial Intelligence (AI) was proposed in [1] but this definition was not absolutely formal at least because the word "Human" was used. In this paper we will formalize the definition from [1]. The biggest problem in this definition was that the level of intelligence of AI is compared to the intelligence of a human being. In order to change this we will introduce some parameters to which AI ...

  4. Advanced Artificial Intelligence Technology Testbed

    Science.gov (United States)

    Anken, Craig S.

    1993-01-01

    The Advanced Artificial Intelligence Technology Testbed (AAITT) is a laboratory testbed for the design, analysis, integration, evaluation, and exercising of large-scale, complex, software systems, composed of both knowledge-based and conventional components. The AAITT assists its users in the following ways: configuring various problem-solving application suites; observing and measuring the behavior of these applications and the interactions between their constituent modules; gathering and analyzing statistics about the occurrence of key events; and flexibly and quickly altering the interaction of modules within the applications for further study.

  5. Epistasis analysis using artificial intelligence.

    Science.gov (United States)

    Moore, Jason H; Hill, Doug P

    2015-01-01

    Here we introduce artificial intelligence (AI) methodology for detecting and characterizing epistasis in genetic association studies. The ultimate goal of our AI strategy is to analyze genome-wide genetics data as a human would using sources of expert knowledge as a guide. The methodology presented here is based on computational evolution, which is a type of genetic programming. The ability to generate interesting solutions while at the same time learning how to solve the problem at hand distinguishes computational evolution from other genetic programming approaches. We provide a general overview of this approach and then present a few examples of its application to real data.

  6. Improving designer productivity. [artificial intelligence

    Science.gov (United States)

    Hill, Gary C.

    1992-01-01

    Designer and design team productivity improves with skill, experience, and the tools available. The design process involves numerous trials and errors, analyses, refinements, and addition of details. Computerized tools have greatly speeded the analysis, and now new theories and methods, emerging under the label Artificial Intelligence (AI), are being used to automate skill and experience. These tools improve designer productivity by capturing experience, emulating recognized skillful designers, and making the essence of complex programs easier to grasp. This paper outlines the aircraft design process in today's technology and business climate, presenting some of the challenges ahead and some of the promising AI methods for meeting these challenges.

  7. Artificial intelligence a beginner's guide

    CERN Document Server

    Whitby, Blay

    2012-01-01

    Tomorrow begins right here as we embark on an enthralling and jargon-free journey into the world of computers and the inner recesses of the human mind. Readers encounter everything from the nanotechnology used to make insect-like robots, to computers that perform surgery, in addition to discovering the biggest controversies to dog the field of AI. Blay Whitby is a Lecturer on Cognitive Science and Artificial Intelligence at the University of Sussex UK. He is the author of two books and numerous papers.

  8. Logical Foundations Of Artificial Intelligence

    Directory of Open Access Journals (Sweden)

    Angel Garrido

    2010-04-01

    Full Text Available The procedures of searching solutions to problems, in Artificial Intelligence, can be brought about, in many occasions, without knowledge of the Domain, and in other situations, with knowledge of it. This last procedure is usually called Heuristic Search. In such methods the matrix techniques reveal themselves as essential. Their introduction can give us an easy and precise way in the search of solution. Our paper explains how the matrix theory appears and fruitfully participates in A I, with feasible applications to Game Theory.

  9. Lower-limb valgus deformity associated with developmental hip dysplasia

    Institute of Scientific and Technical Information of China (English)

    GUO Sheng-jie; ZHOU Yi-xin; YANG De-jin; YANG Xu-cheng

    2012-01-01

    Background Treating developmental dysplasia of the hip is often challenging.The difficulties include not only the hip surgery itself but also the treatment of the associated lower-limb valgus deformity However,there have been very few studies on such deformity in patients with developmental hip dysplasia.In this study,we investigated the prevalence and severity of lower-limb valgus deformity,along with the relationship between the severity ef valgus deformity and mechanical alterations of the hip or the ipsilateral knee.Methods Two hundred and six affected lower limbs of 116 adult patients with untreated developmental dysplasia of the hip were included in the study,grouped according to the severity of hip dysplasia.Each study participant's radiographs were measured to quantitatively evaluate the mechanical axis deviation of the lower limb,and further to evaluate the prevalence and severity of the lower-limb valgus deformity.Some mechanical alterations of the hip and the ipsilateral knee were also measured on the radiographs.Results Of the affected lower limbs,14.1% had valgus deformities.Study participants with Crowe typeⅢ?hip dysplasiahad the most severe deformity and the highest prevalence of deformity.Severity of valgus deformity had a strong positive correlation with the lateral migration of the femoral head but not with the superior migration.A decreased lateral distal femoral angle contributed to the lower-limb valgus deformity,and the lateral distal femoral angle had a strong negative correlation with the severity of valgus deformity.Conclusions Hip dysplasia is commonly associated with lower-limb valgus deformity,and the severity of the lower-limb valgus deformity is mostly affected by lateral migration but not superior migration of the femoral head.The valgus deformity may originate mainly in the distal femur,in addition to the hip joint itself.These findings can be taken into account when planning to treat the patients with hip dysplasia.

  10. An upper limb robot model of children limb for cerebral palsy neurorehabilitation.

    Science.gov (United States)

    Pathak, Yagna; Johnson, Michelle

    2012-01-01

    Robot therapy has emerged in the last few decades as a tool to help patients with neurological injuries relearn motor tasks and improve their quality of life. The main goal of this study was to develop a simple model of the human arm for children affected with cerebral palsy (CP). The Simulink based model presented here shows a comparison for children with and without disabilities (ages 6-15) with normal and reduced range of motion in the upper limb. The model incorporates kinematic and dynamic considerations required for activities of daily living. The simulation was conducted using Matlab/Simulink and will eventually be integrated with a robotic counterpart to develop a physical robot that will provide assistance in activities of daily life (ADLs) to children with CP while also aiming to improve motor recovery.

  11. Critical Limb Ischemia in Association with Charcot Neuroarthropathy: Complex Endovascular Therapy for Limb Salvage

    Energy Technology Data Exchange (ETDEWEB)

    Palena, Luis Mariano, E-mail: marianopalena@hotmail.com [Policlinico Abano Terme, Interventional Radiology Unit (Italy); Brocco, Enrico [Policlinico Abano Terme, Diabetic Foot Department, Foot and Ankle Clinic (Italy); Manzi, Marco [Policlinico Abano Terme, Interventional Radiology Unit (Italy)

    2013-05-09

    Charcot neuroarthropathy is a low-incidence complication of diabetic foot and is associated with ankle and hind foot deformity. Patients who have not developed deep ulcers are managed with offloading and supportive bracing or orthopedic arthrodesis. In patients who have developed ulcers and severe ankle instability and deformity, below-the-knee amputation is often indicated, especially when deformity and cutaneous involvement result in osteomyelitis. Ischemic association has not been described but can be present as a part of peripheral arterial disease in the diabetic population. In this extreme and advanced stage of combined neuroischemic diabetic foot disease, revascularization strategies can support surgical and orthopedic therapy, thus preventing osteomyelitis and leading to limb and foot salvage.

  12. Large Geomagnetic Storms Associated with Limb Halo Coronal Mass Ejections

    CERN Document Server

    Gopalswamy, Nat; Xie, Hong; Akiyama, Sachiko; Makela, Pertti

    2009-01-01

    Solar cycle 23 witnessed the observation of hundreds of halo coronal mass ejections (CMEs), thanks to the high dynamic range and extended field of view of the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO) mission. More than two thirds of halo CMEs originating on the front side of the Sun have been found to be geoeffective (Dst = 45deg) have a 20% shorter delay time on the average. It was suggested that the geomagnetic storms due to limb halos must be due to the sheath portion of the interplanetary CMEs (ICMEs) so that the shorter delay time can be accounted for. We confirm this suggestion by examining the sheath and ejecta portions of ICMEs from Wind and ACE data that correspond to the limb halos. Detailed examination showed that three pairs of limb halos were interacting events. Geomagnetic storms following five limb halos were actually produced by other disk halos. The storms followed by four isolated limb halos and the ones associated with interact...

  13. Ubiquitous human upper-limb motion estimation using wearable sensors.

    Science.gov (United States)

    Zhang, Zhi-Qiang; Wong, Wai-Choong; Wu, Jian-Kang

    2011-07-01

    Human motion capture technologies have been widely used in a wide spectrum of applications, including interactive game and learning, animation, film special effects, health care, navigation, and so on. The existing human motion capture techniques, which use structured multiple high-resolution cameras in a dedicated studio, are complicated and expensive. With the rapid development of microsensors-on-chip, human motion capture using wearable microsensors has become an active research topic. Because of the agility in movement, upper-limb motion estimation has been regarded as the most difficult problem in human motion capture. In this paper, we take the upper limb as our research subject and propose a novel ubiquitous upper-limb motion estimation algorithm, which concentrates on modeling the relationship between upper-arm movement and forearm movement. A link structure with 5 degrees of freedom (DOF) is proposed to model the human upper-limb skeleton structure. Parameters are defined according to Denavit-Hartenberg convention, forward kinematics equations are derived, and an unscented Kalman filter is deployed to estimate the defined parameters. The experimental results have shown that the proposed upper-limb motion capture and analysis algorithm outperforms other fusion methods and provides accurate results in comparison to the BTS optical motion tracker.

  14. Hair patterns of the lower limb in Central Indian males.

    Science.gov (United States)

    Chaurasia, B D

    1977-08-01

    The distribution of hair of the right lower limb has been studied in a random sample of 220 healthy Central Indian males 17 to 45 years of age. The common hair patterns observed are the proximal phalangeal hair in all toes in 55.45%, the middle phalangeal hair in the third toe in 8.18%, the tibial on the dorsum of foot in 69.55%, and the pedo-cruro-femoral in the lower limb in 70.00% subjects. Comparison of these findings with those of the right upper limb shows that hairiness of the two limbs is correlated, that the dorsum of foot is less hairy than the dorsum of hand, and that the third and second toes are comparable with the fourth and third fingers, respectively, as regards their middle phalangeal hair. Comparison with the available literature shows that the Central Indian males resemble the Whites in having greater frequency of middle phalangeal hair than those of the Negroes, that the dorsum of feet of this population is less hairy than the White and more hairy than the Negroes, and that the general hairiness of the lower limb is more or less equal in the three groups of persons.

  15. Teaching Training Method of a Lower Limb Rehabilitation Robot

    Directory of Open Access Journals (Sweden)

    Yongfei Feng

    2016-03-01

    Full Text Available This paper presents a new lower limb rehabilitation robot (hereafter, referred to as LLR-Ro to help patients with lower limb disorder recover their movement function. Based on the ergonomics and kinematics principle, the motion of a human lower limb is analysed, which provides a theoretical basis for the leg mechanism design of LLR-Ro. This paper also proposes a teaching training method for improving the training performance of LLR-Ro. When a physician trains the lower limb of a patient, the acceleration data of the patient’s lower limb motion will be collected through a wireless data acquisition system. The data can reproduce the movement trajectory of the physician rehabilitation training and this can be used as the training trajectory of LLR-Ro. The experiment results of this study demonstrate that the teaching training method is feasible. The theory analysis and experimental research of LLR-Ro lay the foundations for the future clinical application of this method.

  16. Regeneration of limb joints in the axolotl (Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Jangwoo Lee

    Full Text Available In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

  17. Regeneration of limb joints in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Lee, Jangwoo; Gardiner, David M

    2012-01-01

    In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander) model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

  18. Macroevolutionary diversity of amniote limb proportions predicted by developmental interactions.

    Science.gov (United States)

    Young, Nathan M

    2013-11-01

    Mammals, birds, and reptiles exhibit a remarkable diversity of limb proportions. These evolved differences are thought to reflect selection for biomechanical, postural, and locomotor requirements primarily acting on independent variation in later fetal and postnatal segmental growth. However, earlier conserved developmental events also have the potential to impact the evolvability of limb proportions by limiting or biasing initial variation among segments. Notably, proximo-distal patterning of the amniote limb through activation-inhibition dynamics predicts that initial proportions of segments should exhibit both tradeoffs between stylopod and autopod and a diagnostic reduction in variance of the zeugopod. Here it is demonstrated that this developmental "design rule" predicts patterns of macroevolutionary diversity despite the effects of variation in segmental growth over ontogeny, lineage-specific differences in phylogenetic history, or functional adaptation. These results provide critical comparative evidence of a conserved Turing-like mechanism in proximo-distal limb segmentation, and suggest that development has played a previously unrecognized role in the evolvability of limb proportions in a wide range of amniote taxa.

  19. A computational clonal analysis of the developing mouse limb bud.

    Directory of Open Access Journals (Sweden)

    Luciano Marcon

    Full Text Available A comprehensive spatio-temporal description of the tissue movements underlying organogenesis would be an extremely useful resource to developmental biology. Clonal analysis and fate mappings are popular experiments to study tissue movement during morphogenesis. Such experiments allow cell populations to be labeled at an early stage of development and to follow their spatial evolution over time. However, disentangling the cumulative effects of the multiple events responsible for the expansion of the labeled cell population is not always straightforward. To overcome this problem, we develop a novel computational method that combines accurate quantification of 2D limb bud morphologies and growth modeling to analyze mouse clonal data of early limb development. Firstly, we explore various tissue movements that match experimental limb bud shape changes. Secondly, by comparing computational clones with newly generated mouse clonal data we are able to choose and characterize the tissue movement map that better matches experimental data. Our computational analysis produces for the first time a two dimensional model of limb growth based on experimental data that can be used to better characterize limb tissue movement in space and time. The model shows that the distribution and shapes of clones can be described as a combination of anisotropic growth with isotropic cell mixing, without the need for lineage compartmentalization along the AP and PD axis. Lastly, we show that this comprehensive description can be used to reassess spatio-temporal gene regulations taking tissue movement into account and to investigate PD patterning hypothesis.

  20. Progressive thinning of visual motion area in lower limb amputees

    Directory of Open Access Journals (Sweden)

    Guangyao eJiang

    2016-03-01

    Full Text Available Accumulating evidence has indicated that amputation or deafferentation of a limb induces functional or structural reorganization in the visual areas. However, the extent of the visual areas involved after lower limb amputation remains uncertain. In this investigation, we studied 48 adult patients with unilateral lower limb amputation and 48 matched healthy controls using T1-weighted magnetic resonance imaging. Template-based regions of interest analysis was implemented to detect the changes of cortical thickness in the specific visual areas. Compared with normal controls, amputees exhibited significantly lower thickness in the V5/middle temporal (V5/MT+ visual area, as well as a trend of cortical thinning in the V3d. There was no significant difference in the other visual areas between the two groups. In addition, no significant difference of cortical thickness was found between patients with amputation at different levels. Across all amputees, correlation analyses revealed that the cortical thickness of the V5/MT+ was negatively correlated to the time since amputation. In conclusion, our findings indicate that the amputation of unilateral lower limb could induce changes in the motor-related visual cortex, and provide an update on the plasticity of the human brain after limb injury.

  1. [Artificial crowns influence upon edge parodontium status].

    Science.gov (United States)

    Zhulev, E N; Serov, A B

    2010-01-01

    With the aim of prosthetic treatment efficacy increase study of edge parodontium tissue reaction upon different types of artificial crowns was done and methods of chronic localized parodontitis prevention were developed. Changes of the main gingival fluid characteristics (amount, acidity, interleukine-1beta concentration) and indicators of microcirculation in edge parodontium of the teeth under the artificial crowns influence were disclosed. There were developed methods of chronic localized parodontitis prevention produced by artificial crowns edge.

  2. Semantic Interpretation of An Artificial Neural Network

    Science.gov (United States)

    1995-12-01

    ARTIFICIAL NEURAL NETWORK .7,’ THESIS Stanley Dale Kinderknecht Captain, USAF 770 DEAT7ET77,’H IR O C 7... ARTIFICIAL NEURAL NETWORK THESIS Stanley Dale Kinderknecht Captain, USAF AFIT/GCS/ENG/95D-07 Approved for public release; distribution unlimited The views...Government. AFIT/GCS/ENG/95D-07 SEMANTIC INTERPRETATION OF AN ARTIFICIAL NEURAL NETWORK THESIS Presented to the Faculty of the School of Engineering of

  3. ARTIFICIAL LIVING SYSTEM AND ITS COMPLEXITY

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yongguang

    2001-01-01

    In this paper the author shows some artificial living systems, whose basic life characteristics are explored, especially the differentiation in evolution from single cellular to multi-cellular organism. In addition, the author discusses diversity and evolvability also.The author gives a modified entropy function to measure the diversity. Finally, the author drops an open problem about the structure of "gene" of artificial living systems, so that we can measure the evolutionary order between the artificial living systems.

  4. Meta-Learning Evolutionary Artificial Neural Networks

    OpenAIRE

    Abraham, Ajith

    2004-01-01

    In this paper, we present MLEANN (Meta-Learning Evolutionary Artificial Neural Network), an automatic computational framework for the adaptive optimization of artificial neural networks wherein the neural network architecture, activation function, connection weights; learning algorithm and its parameters are adapted according to the problem. We explored the performance of MLEANN and conventionally designed artificial neural networks for function approximation problems. To evaluate the compara...

  5. Progress and Challenge of Artificial Intelligence

    Institute of Scientific and Technical Information of China (English)

    Zhong-Zhi Shi; Nan-Ning Zheng

    2006-01-01

    Artificial Intelligence (AI) is generally considered to be a subfield of computer science, that is concerned to attempt simulation, extension and expansion of human intelligence. Artificial intelligence has enjoyed tremendous success over the last fifty years. In this paper we only focus on visual perception, granular computing, agent computing, semantic grid. Human-level intelligence is the long-term goal of artificial intelligence. We should do joint research on basic theory and technology of intelligence by brain science, cognitive science, artificial intelligence and others. A new cross discipline intelligence science is undergoing a rapid development. Future challenges are given in final section.

  6. Artificial senses for characterization of food quality

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan-bo; LAN Yu-bin; R.E. Lacey

    2004-01-01

    Food quality is of primary concern in the food industry and to the consumer. Systems that mimic human senses have been developed and applied to the characterization of food quality. The five primary senses are: vision, hearing, smell, taste and touch.In the characterization of food quality, people assess the samples sensorially and differentiate "good" from "bad" on a continuum.However, the human sensory system is subjective, with mental and physical inconsistencies, and needs time to work. Artificial senses such as machine vision, the electronic ear, electronic nose, electronic tongue, artificial mouth and even artificial the head have been developed that mimic the human senses. These artificial senses are coordinated individually or collectively by a pattern recognition technique, typically artificial neural networks, which have been developed based on studies of the mechanism of the human brain. Such a structure has been used to formulate methods for rapid characterization of food quality. This research presents and discusses individual artificial sensing systems. With the concept of multi-sensor data fusion these sensor systems can work collectively in some way. Two such fused systems, artificial mouth and artificial head, are described and discussed. It indicates that each of the individual systems has their own artificially sensing ability to differentiate food samples. It further indicates that with a more complete mimic of human intelligence the fused systems are more powerful than the individual systems in differentiation of food samples.

  7. Artificial Promoters for Metabolic Optimization

    DEFF Research Database (Denmark)

    Jensen, Peter Ruhdal; Hammer, Karin

    1998-01-01

    In this article, we review some of the expression systems that are available for Metabolic Control Analysis and Metabolic Engineering, and examine their advantages and disadvantages in different contexts. In a recent approach, artificial promoters for modulating gene expression in micro-organisms......In this article, we review some of the expression systems that are available for Metabolic Control Analysis and Metabolic Engineering, and examine their advantages and disadvantages in different contexts. In a recent approach, artificial promoters for modulating gene expression in micro......-organisms were constructed using synthetic degenerated oligonucleotides. From this work, a promoter library was obtained for Lactococcus lactis, containing numerous individual promoters and covering a wide range of promoter activities. Importantly, the range of promoter activities was covered in small steps...... of activity change. Promoter libraries generated by this approach allow for optimization of gene expression and for experimental control analysis in a wide range of biological systems by choosing from the promoter library promoters giving, e.g., 25%, 50%, 200%, and 400% of the normal expression level...

  8. Artificial neural networks in neurosurgery.

    Science.gov (United States)

    Azimi, Parisa; Mohammadi, Hasan Reza; Benzel, Edward C; Shahzadi, Sohrab; Azhari, Shirzad; Montazeri, Ali

    2015-03-01

    Artificial neural networks (ANNs) effectively analyze non-linear data sets. The aimed was A review of the relevant published articles that focused on the application of ANNs as a tool for assisting clinical decision-making in neurosurgery. A literature review of all full publications in English biomedical journals (1993-2013) was undertaken. The strategy included a combination of key words 'artificial neural networks', 'prognostic', 'brain', 'tumor tracking', 'head', 'tumor', 'spine', 'classification' and 'back pain' in the title and abstract of the manuscripts using the PubMed search engine. The major findings are summarized, with a focus on the application of ANNs for diagnostic and prognostic purposes. Finally, the future of ANNs in neurosurgery is explored. A total of 1093 citations were identified and screened. In all, 57 citations were found to be relevant. Of these, 50 articles were eligible for inclusion in this review. The synthesis of the data showed several applications of ANN in neurosurgery, including: (1) diagnosis and assessment of disease progression in low back pain, brain tumours and primary epilepsy; (2) enhancing clinically relevant information extraction from radiographic images, intracranial pressure processing, low back pain and real-time tumour tracking; (3) outcome prediction in epilepsy, brain metastases, lumbar spinal stenosis, lumbar disc herniation, childhood hydrocephalus, trauma mortality, and the occurrence of symptomatic cerebral vasospasm in patients with aneurysmal subarachnoid haemorrhage; (4) the use in the biomechanical assessments of spinal disease. ANNs can be effectively employed for diagnosis, prognosis and outcome prediction in neurosurgery.

  9. Artificial Shortages and Strategic Pricing

    Directory of Open Access Journals (Sweden)

    Partha Gangopadhyay

    2012-01-01

    Full Text Available Problem statement: We consider a monopolist who manipulates the market by artificially creating shortages that result in an increase in current price that, in turn, boosts demand for the product in subsequent periods. The approach is to develop an intertemporal model of pricing strategy for a monopolist. Approach: The postulated pricing strategy creates an incentive for producers to reduce current supply and raise current prices and sacrifice current profits in order to increase future profits. The main problem is to explain the precise mathematical conditions under which the pricing strategy will be chosen by a monopolist. Results: We derive the optimal pricing strategy to argue that the monopolist has an incentive to adopt simple market manipulation that calls forth a close examination of issues concerning deregulation. Conclusion: The paper examines two possible strategies for a typical monopolist-strategic pricing vis-a-vis a myopic pricing. The intuition is that the monopolist can manipulate the market by artificially creating shortages that result in an increase in current price that, in turn, boosts demand for the product in subsequent periods.

  10. Artificial muscle: facts and fiction.

    Science.gov (United States)

    Schaub, Marcus C

    2011-12-19

    Mechanical devices are sought to support insufficient or paralysed striated muscles including the failing heart. Nickel-titanium alloys (nitinol) present the following two properties: (i) super-elasticity, and (ii) the potential to assume different crystal structures depending on temperature and/or stress. Starting from the martensite state nitinol is able to resume the austenite form (state of low potential energy and high entropy) even against an external resistance. This one-way shape change is deployed in self-expanding vascular stents. Heating induces the force generating transformation from martensite to the austenite state while cooling induces relaxation back to the martensite state. This two-way shape change oscillating between the two states may be used in cyclically contracting support devices of silicon-coated nitinol wires. Such a contractile device sutured to the right atrium has been tested in vitro in a bench model and in vivo in sheep. The contraction properties of natural muscles, specifically of the myocardium, and the tight correlation with ATP production by oxidative phosphorylation in the mitochondria is briefly outlined. Force development by the nitinol device cannot be smoothly regulated as in natural muscle. Its mechanical impact is forced onto the natural muscle regardless of the actual condition with regard to metabolism and Ca2+-homeostasis. The development of artificial muscle on the basis of nitinol wires is still in its infancy. The nitinol artificial muscle will have to prove its viability in the various clinical settings.

  11. CLINICAL EFFECTS OF REVASCULARIZATION IN LOWER LIMB ISCHEMIA%血运重建治疗下肢动脉缺血的临床分析

    Institute of Scientific and Technical Information of China (English)

    李晓曦; 吕伟明; 常光其; 吴壮宏; 林勇杰

    2001-01-01

    目的总结对严重下肢动脉缺血患者重建患肢血供的临床效果。方法对1995年1月~2000年12月间重建肢体血液循环的49例56侧肢体进行回顾性分析。动脉闭塞分别位于近肾腹主动脉-双髂动脉,腹主动脉-双髂动脉,髂动脉,股动脉或股-月国动脉。手术指征是间歇性跛行,静息痛和趾端坏疽。手术方式是股动静脉转流术12例14侧肢体,人造血管旁路搭桥术28例33侧肢体,动脉内膜切除及股深动脉补片成形术5例5侧肢体,一期截肢4例。结果术后随访平均38个月。在重建血运的52侧肢体中,4侧出现患肢坏疽而截肢;共截肢8侧,累计截肢率为14.3%。人造血管旁路搭桥术、动脉内膜切除及股深动脉补片成形状的肢体血流通畅率为68.4%(26/38侧肢体),保肢率为94.7%(36/38侧肢体); 股动静脉转流术的保肢率为85.7%(12/14侧肢体)。结论血运重建是救治下肢动脉闭塞患肢的有效方法,应根据具体情况选择动脉旁路搭桥、动脉内膜切除及股深动脉补片成形或股动静脉转流术。动脉造影是重建手术成功的必要保证。%Objective To investigate the clinical effects of revascularization in lower extremity for severe ischemia. Methods Fifty-six lower limbs with severe ischemia in 49 patients were evaluated retrospectively, who underwent surgical intervention from January of 1995 to December of 2000. By arteriography, the actual anatomic distributions of occlusive disease included infrarenal aorta-bicommon iliac arteries, abdominal aorta-bicommon iliac arteries, iliac artery, and femoral artery or femoropopliteal artery. The indication for surgery was disabling claudication, rest pain and gangrene. Fourteen limbs in 12 cases received arterialization of femoral venous system by artificial venous-arterial fistula. Artificial vascular grafts were implanted in 33 limbs of 28 cases, endarterectomy and patch profundaplasty were performed

  12. A Pathway to Artificial Metalloenzymes

    KAUST Repository

    Fischer, Johannes

    2015-12-01

    The advancement of catalytic systems and the application thereof has proven to be the key to overcome traditional limitations of industrial-scale synthetic processes. Converging organometallic and biocatalytic principles lead to the development of Artificial Metalloenzymes (ArMs) that comprise a synthetic metal catalyst embedded in a protein scaffold, thereby combining the reactivity of the former with the versatility of the latter. This synergistic approach introduces rationally designed building blocks for the catalytic site and the host protein to assemble enzyme-like structures that follow regio-, chemo-, enantio- and substrate-selective principles. Yet, the identification of suitable protein scaffolds has thus far been challenging. Herein we report a rationally optimized fluorescent protein host, mTFP*, that was engineered to have no intrinsic metal binding capability and, owing to its robust nature, can act as scaffold for the design of novel ArMs. We demonstrate the potential of site-specific modifications within the protein host, use protein X-Ray analysis to validate the respective scaffolds and show how artificial mutant binding sites can be introduced. Transition metal Förster Resonance Energy transfer (tmFRET) methodologies help to evaluate micromolar dissociation constants and reveal structural rearrangements upon coordination of the metal centers. In conjunction with molecular insights from X-Ray crystallographic structure determination, dynamics of the binding pocket can be inferred. The versatile subset of different binding motifs paired with transition metal catalysts create artificial metalloenzymes that provide reactivities which otherwise do not exist in nature. As a proof of concept, Diels-Alder cycloadditions highlight the potential of the present mTFP* based catalysts by stereoselectively converting azachalcone and cyclopentadiene substrates. Screens indicate an enantiomeric excess of up to 60% and provide insights into the electronic and

  13. Benign monomelic amyotrophy of lower limb: report of three cases.

    Science.gov (United States)

    Uncini, A; Servidei, S; Delli Pizzi, C; Cutarella, R; Di Muzio, A; Gambi, D; Tonali, P

    1992-06-01

    Three patients with wasting confined to a single lower limb are reported. The characteristic features were: sporadic occurrence, insidious onset with slow progression and in 2 cases arrested course for at least 4 years, wasting out of proportion with disability, absence of sensory, pyramidal tract or bulbar signs. CK, motor and sensory conductions, and lumbar MRI were normal. Muscle CT showed selective loss of muscle tissue and fat replacement in posterior leg muscles. Quantitative electromyography and histologic findings revealed neurogenic features not only in the affected legs, but also in clinically uninvolved limbs. Monomelic amyotrophy of lower limb is a variant of spinal muscular atrophy with a benign course. However, as in the early stages of the disease there are no distinctive clinical or laboratory findings with other motor neuron diseases, the diagnosis of monomelic amyotrophy may be made only retrospectively after a prolonged observation.

  14. Cross-over limb replantation: a case report.

    Science.gov (United States)

    Holmes, W J M; Williams, A; Everitt, K J M; Kay, S P J; Bourke, G

    2013-10-01

    Following traumatic bilateral arm amputation in a 46-year-old woman, orthotopic replantation was not possible. The patient underwent replantation of the left forearm to the right proximal forearm. At two years she has a sensate hand, with good recovery of her long flexors of the hand and wrist extensors. DASH score is 93.9 and Chen's score is III (medium). We demonstrate a high level of function compared to the contralateral prosthetic limb. There have only been four similar cases described. Although a rare circumstance, a cross-limb replant can provide a level of function and independence superior to a simple prosthesis. Cross-limb transfer should be considered in situations where bilateral arm amputation is present and neither can be orthotopically replanted.

  15. Necrotising fasciitis of upper and lower limb: a systematic review.

    Science.gov (United States)

    Angoules, A G; Kontakis, G; Drakoulakis, E; Vrentzos, G; Granick, M S; Giannoudis, P V

    2007-12-01

    Necrotising fasciitis is a rapidly progressive, life threatening soft tissue infection. In a significant proportion of patients, the extremities are involved as a result of trauma, needle puncture or extravasation of drugs, often leading to limb loss and devastating disability. In this systematic review of necrotising fasciitis of the upper and lower extremities, we report on the clinical characteristics, the predisposing factors, the associated diseases, the pathogenic bacteria, the surgical treatment and the final outcome in terms of limb loss and mortality. Data for a total of 451 patients were analysed for each parameter of interest. A percentage of 22.3% of the reviewed patients underwent amputation or disarticulation of a limb following failure of multiple debridements to control infection and the mortality rate was estimated as high as 21.9%.

  16. Laser angioplasty of totally occluded arteries of the limb

    Science.gov (United States)

    Szopinski, Piotr; Hara, Marek; Noszczyk, Wojciech

    1996-03-01

    The authors summarize their experience in the use of Nd-YAG laser in chronic occlusion of lower limb arteries. Percutaneous transluminal laser angioplasty (PTLA) with laser-heated metal and sapphire tips were used as an adjuvant to conventional balloon angioplasty. In cases of reocclusions, endovascular stents were implanted. Laser recanalization was performed in 46 arteries (iliac, superficial femoral, and popliteal). Indications for the procedure were: limb salvage, claudication below 100 m, and temporal or rest pain. Initial clinical and hemodynamic improvement was observed in 37 (80%) patients. Four perforations occurred without clinical sequel. The one-year cumulative clinical patency was 27 (58%) of the 46 lesions. PTLA may be appropriate for high-risk patients, who are unsuitable for surgical reconstruction because of the concomitant diseases. The combination of laser recanalization and implantation of vascular stents may be a promising method in the management of limb ischemia.

  17. Myogenic potential of chick limb bud mesenchyme in micromass culture.

    Science.gov (United States)

    Archer, C W; Langille, R M; Teran, M A; Solursh, M

    1992-01-01

    The myogenic potential of chick limb mesenchyme from stages 18-25 was assessed by micromass culture under conditions conductive to myogenesis, and was measured as the proportion of differentiated (muscle myosin-positive) mononucleated cells detected. It was found that similar myogenic potentials existed in mesenchyme from whole limbs between stages 18 and 19, but this potential was halved by stage 20. At stage 21, proximal mesenchyme showed significantly more myogenesis than distal mesenchyme, but this difference was abolished by stage 22. Thereafter, myogenesis was increasingly restricted from the distal mesenchyme, whilst the potential in more proximal regions did not significantly increase after stage 23. When the ratio between total limb myoblasts which differentiated on days 1 and 4 of culture was analysed, it was found that two distinct peaks existed at stages 20 and 23. The significance of these ratio peaks is unclear, but may be related to different proliferative potentials of the pre-myoblasts at these stages.

  18. The many lives of SHH in limb development and evolution.

    Science.gov (United States)

    Lopez-Rios, Javier

    2016-01-01

    The SHH signaling pathway is essential for proper formation of the limb skeleton, as is required for the survival and expansion of distal chondrogenic progenitor cells. At the same time, SHH is important to specify digit identities along the anterior-posterior axis. Upon gain or loss of activity of the SHH pathway, bones are gained, lost or malformed, and such deregulation underlies the aetiology of various human congenital limb defects. Likewise, accumulating evidence suggests that evolutionary tampering with SHH signaling underlies the morphological diversification of the tetrapod appendicular skeleton. This review summarizes the roles of the SHH pathway in the context of limb development and evolution and incorporates recent evidence into a mechanistic view of how the positioning of digit condensations is integrated with the specification of distinct bone morphologies.

  19. Obstacle crossing following stroke improves over one month when the unaffected limb leads, but not when the affected limb leads.

    Science.gov (United States)

    Said, Catherine M; Galea, Mary; Lythgo, Noel

    2014-01-01

    While it is well established that obstacle crossing is impaired following stroke, it is not known whether obstacle crossing improves as gait improves following stroke. The purpose of this study was to determine whether obstacle crossing changed over a one month time period in people with a recent stroke. Twenty participants receiving rehabilitation following a recent stroke were tested on two occasions one month apart. Participants received usual care rehabilitation, including physiotherapy, between the tests. The main outcome measure was obstacle crossing speed as participants stepped over a 4-cm high obstacle. Secondary measures were spatiotemporal variables. Data were collected via a three dimensional motion analysis system. When leading with the affected limb no changes in obstacle crossing speed or spatiotemporal variables were observed over the one month period. When leading with the unaffected limb, crossing speed significantly increased (p=.002), and affected trail limb swing time (p=.03) and crossing step double support time reduced (p=.016). While not significant, the lead and trail limb pre-obstacle distance increased (p=.08), and lead swing time (p=.052) reduced. Change in obstacle crossing speed did not correlate with change in level gait speed. Obstacle crossing does not necessarily improve over a one month time period in people receiving rehabilitation following stroke. These findings suggest that there may be a need for more targeted training of obstacle crossing, particularly when leading with the affected limb.

  20. Early delayed amputation: a paradigm shift in the limb-salvage time line for patients with major upper-limb injury.

    Science.gov (United States)

    Burdette, Todd E; Long, Sarah A; Ho, Oscar; Demas, Chris; Bell, John-Erik; Rosen, Joseph M

    2009-01-01

    Patients with major injuries to the upper limbs sometimes fail to achieve successful limb salvage. During the attempt to fashion a functional limb, multiple painful procedures may be ventured. Despite the best efforts of surgeons and therapists, a nonfunctioning or painful upper limb may remain in place for many months or years before late delayed amputation and progression to productive rehabilitation occur. We present three patient cases that illustrate failed upper-limb salvage. In each case, patients expressed a desire for amputation at 6 months after their injury. To reduce the pain and suffering that patients with failed limb salvage endure, we propose a paradigm shift in the limb-salvage time line. We suggest that patients be evaluated for early delayed amputation 6 months after their injury.

  1. Shared Enhancer Activity in the Limbs and Phallus and Functional Divergence of a Limb-Genital cis-Regulatory Element in Snakes.

    Science.gov (United States)

    Infante, Carlos R; Mihala, Alexandra G; Park, Sungdae; Wang, Jialiang S; Johnson, Kenji K; Lauderdale, James D; Menke, Douglas B

    2015-10-12

    The amniote phallus and limbs differ dramatically in their morphologies but share patterns of signaling and gene expression in early development. Thus far, the extent to which genital and limb transcriptional networks also share cis-regulatory elements has remained unexplored. We show that many limb enhancers are retained in snake genomes, suggesting that these elements may function in non-limb tissues. Consistent with this, our analysis of cis-regulatory activity in mice and Anolis lizards reveals that patterns of enhancer activity in embryonic limbs and genitalia overlap heavily. In mice, deletion of HLEB, an enhancer of Tbx4, produces defects in hindlimbs and genitalia, establishing the importance of this limb-genital enhancer for development of these different appendages. Further analyses demonstrate that the HLEB of snakes has lost hindlimb enhancer function while retaining genital activity. Our findings identify roles for Tbx4 in genital development and highlight deep similarities in cis-regulatory activity between limbs and genitalia.

  2. 假肢发展技术以及截肢患者假肢安装过程中的心理康复%Artificial limb development and the mental rehabilitation of patients undergoing amputation and artificial limb installation

    Institute of Scientific and Technical Information of China (English)

    赵琳

    2009-01-01

    随着大量新技术和新材料引入假肢领域,实现了假肢的钛合金化、碳纤维化和计算机智能化控制,极大地提高了截肢患者的生活质量.在截肢与假肢治疗中常见的相关心理问题有抑郁、焦虑恐惧、自我概念的改变、强迫的敏感性增高、社会适应力改变等.截肢与假肢治疗康复应包括躯体和心理两个方面.针对病情不同、年龄不同、社会文化背景不同、经济条件不同等,针对性地疏导和帮助患者,使之勇敢面对现实,树立勇气战胜伤残,回归生活,回归社会.

  3. The Biological Relevance of Artificial Life: Lessons from Artificial Intelligence

    Science.gov (United States)

    Colombano, Silvano

    2000-01-01

    There is no fundamental reason why A-life couldn't simply be a branch of computer science that deals with algorithms that are inspired by, or emulate biological phenomena. However, if these are the limits we place on this field, we miss the opportunity to help advance Theoretical Biology and to contribute to a deeper understanding of the nature of life. The history of Artificial Intelligence provides a good example, in that early interest in the nature of cognition quickly was lost to the process of building tools, such as "expert systems" that, were certainly useful, but provided little insight in the nature of cognition. Based on this lesson, I will discuss criteria for increasing the biological relevance of A-life and the probability that this field may provide a theoretical foundation for Biology.

  4. 100 top-cited scientific papers in limb prosthetics.

    Science.gov (United States)

    Eshraghi, Arezoo; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq; Shadgan, Babak

    2013-11-17

    Research has tremendously contributed to the developments in both practical and fundamental aspects of limb prosthetics. These advancements are reflected in scientific articles, particularly in the most cited papers. This article aimed to identify the 100 top-cited articles in the field of limb prosthetics and to investigate their main characteristics. Articles related to the field of limb prosthetics and published in the Web of Knowledge database of the Institute for Scientific Information (ISI) from the period of 1980 to 2012. The 100 most cited articles in limb prosthetics were selected based on the citation index report. All types of articles except for proceedings and letters were included in the study. The study design and level of evidence were determined using Sackett's initial rules of evidence. The level of evidence was categorized either as a systematic review or meta-analysis, randomized controlled trial, cohort study, case-control study, case series, expert opinion, or design and development. The top cited articles in prosthetics were published from 1980 to 2012 with a citation range of 11 to 90 times since publication. The mean citation rate was 24.43 (SD 16.7) times. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) and case series studies (67%) that used human subjects (96%) providing level 4 evidence. Among the various fields, rehabilitation (47%), orthopedics (29%), and sport sciences (28%) were the most common fields of study. The study established that studies conducted in North America and were written in English had the highest citations. Top cited articles primarily dealt with lower limb prosthetics, specifically, on transtibial and transradial prosthetic limbs. Majority of the articles were experimental studies.

  5. Stellate ganglion blockade for analgesia following upper limb surgery.

    LENUS (Irish Health Repository)

    McDonnell, J G

    2012-01-31

    We report the successful use of a stellate ganglion block as part of a multi-modal postoperative analgesic regimen. Four patients scheduled for orthopaedic surgery following upper limb trauma underwent blockade of the stellate ganglion pre-operatively under ultrasound guidance. Patients reported excellent postoperative analgesia, with postoperative VAS pain scores between 0 and 2, and consumption of morphine in the first 24 h ranging from 0 to 14 mg. While these are preliminary findings, and must be confirmed in a clinical trial, they highlight the potential for stellate ganglion blockade to provide analgesia following major upper limb surgery.

  6. Transparent biocompatible sensor patches for touch sensitive prosthetic limbs

    KAUST Repository

    Nag, Anindya

    2016-12-26

    The paper presents the fabrication of transparent, flexible sensor patches developed using a casting technique with polydimethylsiloxane (PDMS) as substrate and a nanocomposite of carbon nanotubes (CNTs) and PDMS as interdigital electrodes. The electrodes act as strain sensitive capacitor. The prototypes were used as touch sensitive sensors attached to the limbs. Experiments results show the sensitivity of the patches towards tactile sensing. The results are very promising and can play a key role in the development of a cost efficient sensing system attached to prosthetic limbs.

  7. Upper limb swelling following mastectomy: lymphedema or not?

    Science.gov (United States)

    Armer, Jane

    2007-04-01

    Having experienced an excisional biopsy, sentinel lymph node biopsy, and mastectomy, BH is at lifetime risk of developing post-breast cancer lymphedema in the arm on the side where her breast cancer was treated. She has two additional risk factors, among those documented in the literature: history of an infection (specifically a systemic infection, significant in that it required hospitalization for intravenous antibiotics) in the postsurgery period, and a moderate increase in bilateral limb volume and weight (body mass index) over the months and years following the breast cancer diagnosis. Further, the patient-reported transient hand swelling on the affected side and gradual weight increase are cues indicating a need for patient vigilance and careful monitoring by the health-care team. Preventing future infections, managing weight at an optimal level, and preventing trauma or injury to the affected arm and chest are important self-management precautions to reduce risk of chronic lymphedema development. BH needs continued support in reviewing evidence-based risk-reduction guidelines and understanding ways to apply them to her lifestyle. In the absence of preoperative baseline or contralateral limb measurements (with circumferences or perometry or water displacement), assessment of limb change at a level identified as diagnostic of lymphedema (commonly, 200-mL volume or 2-cm girth increase from baseline or as compared to the contralateral limb) is very challenging. Without bilateral preop limb measurements for baseline and contralateral limb comparisons, BH might have been diagnosed with lymphedema at postop or at 48 months, when both limbs increased symmetrically. Symptom assessment is also crucial, as symptom report of heaviness and swelling is found to be associated with limb volume changes indicative of lymphedema. Transient hand swelling may be evidence of latent lymphedema and cause for increased risk-reduction education and vigilance in assessment for

  8. Prevention and management of limb contractures in neuromuscular diseases.

    Science.gov (United States)

    Skalsky, Andrew J; McDonald, Craig M

    2012-08-01

    Limb contractures are a common impairment in neuromuscular diseases. They contribute to increased disability from decreased motor performance, mobility limitations, reduced functional range of motion, loss of function for activities of daily living, and increased pain. The pathogenesis of contractures is multifactorial. Myopathic conditions are associated with more severe limb contractures compared with neuropathic disorders. Although the evidence supporting the efficacy of multiple interventions to improve range of motion in neuromuscular diseases in a sustained manner is lacking, there are generally accepted principles with regard to splinting, bracing, stretching, and surgery that help minimize the impact or disability from contractures.

  9. Proteus syndrome: A rare cause of gigantic limb

    Directory of Open Access Journals (Sweden)

    Nandini Chakrabarti

    2014-01-01

    Full Text Available A congenital disorder with variable manifestations, including partial gigantism of the hands and feet with hypertrophy of soles, nevi, hemihypertrophy, gynecomastia, macrocephaly and other skull abnormalities, and abdominal lipomatosis. The cause is unknown, although a genetic origin, generally of autosomal-dominant transmission, has been conjectured. Symptoms can be treated, but there is no known cure. We present the case of a young male with grotesque overgrowth of the right lower limb, splenomegaly and multiple nevi. Angiography revealed venous malformation within the limb. The findings are in conformity to the criteria for the Proteus syndrome.

  10. Network based transcription factor analysis of regenerating axolotl limbs

    Directory of Open Access Journals (Sweden)

    Cameron Jo Ann

    2011-03-01

    Full Text Available Abstract Background Studies on amphibian limb regeneration began in the early 1700's but we still do not completely understand the cellular and molecular events of this unique process. Understanding a complex biological process such as limb regeneration is more complicated than the knowledge of the individual genes or proteins involved. Here we followed a systems biology approach in an effort to construct the networks and pathways of protein interactions involved in formation of the accumulation blastema in regenerating axolotl limbs. Results We used the human orthologs of proteins previously identified by our research team as bait to identify the transcription factor (TF pathways and networks that regulate blastema formation in amputated axolotl limbs. The five most connected factors, c-Myc, SP1, HNF4A, ESR1 and p53 regulate ~50% of the proteins in our data. Among these, c-Myc and SP1 regulate 36.2% of the proteins. c-Myc was the most highly connected TF (71 targets. Network analysis showed that TGF-β1 and fibronectin (FN lead to the activation of these TFs. We found that other TFs known to be involved in epigenetic reprogramming, such as Klf4, Oct4, and Lin28 are also connected to c-Myc and SP1. Conclusions Our study provides a systems biology approach to how different molecular entities inter-connect with each other during the formation of an accumulation blastema in regenerating axolotl limbs. This approach provides an in silico methodology to identify proteins that are not detected by experimental methods such as proteomics but are potentially important to blastema formation. We found that the TFs, c-Myc and SP1 and their target genes could potentially play a central role in limb regeneration. Systems biology has the potential to map out numerous other pathways that are crucial to blastema formation in regeneration-competent limbs, to compare these to the pathways that characterize regeneration-deficient limbs and finally, to identify stem

  11. NOTE: The Shape of Triton from Limb Profiles

    Science.gov (United States)

    Thomas, P. C.

    2000-12-01

    Limb profiles from Voyager 2 images of Triton show it to be an ellipsoid of axes 1354.6, 1352.8, and 1352.4 km (±0.9 km). Topography on the limbs suggests no large provinces such as "continents" with relief over a kilometer. The shape solution is not accurate enough to constrain Triton's moments of inertia. The apparently relaxed shape is consistent with the youthful geologic features and supports interpretations that atmospheric distortion suggested by occultation data is due to atmospheric phenomena rather than physical body distortions.

  12. Intuitive, online, simultaneous, and proportional myoelectric control over two degrees-of-freedom in upper limb amputees.

    Science.gov (United States)

    Jiang, Ning; Rehbaum, Hubertus; Vujaklija, Ivan; Graimann, Bernhard; Farina, Dario

    2014-05-01

    We propose an approach for online simultaneous and proportional myoelectric control of two degrees-of-freedom (DoF) of the wrist, using surface electromyographic signals. The method is based on the nonnegative matrix factorization (NMF) of the wrist muscle activation to extract low-dimensional control signals translated by the user into kinematic variables. This procedure does not need a training set of signals for which the kinematics is known (labeled dataset) and is thus unsupervised (although it requires an initial calibration without labeled signals). The estimated control signals using NMF are used to directly control two DoFs of wrist. The method was tested on seven subjects with upper limb deficiency and on seven able-bodied subjects. The subjects performed online control of a virtual object with two DoFs to achieve goal-oriented tasks. The performance of the two subject groups, measured as the task completion rate, task completion time, and execution efficiency, was not statistically different. The approach was compared, and demonstrated to be superior to the online control by the industrial state-of-the-art approach. These results show that this new approach, which has several advantages over the previous myoelectric prosthetic control systems, has the potential of providing intuitive and dexterous control of artificial limbs for amputees.

  13. Endovascular therapy as the primary approach for limb salvage in patients with critical limb ischemia: experience with 443 infrapopliteal procedures.

    Science.gov (United States)

    Bosiers, Marc; Hart, Joseph P; Deloose, Koen; Verbist, Jurgen; Peeters, Patrick

    2006-01-01

    Endovascular strategies for the treatment of critical infrageniculate peripheral arterial occlusive disease exist and are becoming the primary methodology for such lesions at many centers. Although technically feasible for experienced operators, the evidence to support this strategy for below the knee (BTK) interventions is still evolving. We studied the 6-month and 1-year outcomes of percutaneous transluminal angioplasty (PTA) alone, PTA with stenting, and excimer laser recanalization for BTK lesions in patients with critical limb ischemia. Between September 2002 and June 2005, 443 patients (355 Rutherford category 4, 82 category 5, 6 category 6) underwent intervention for 681 BTK lesions. Follow-up was performed at 6-month intervals after index intervention: limb salvage data were recorded and duplex ultrasonography was performed to measure the patency of treated areas. The primary patency and limb salvage rates of the entire population were 85.2% and 97.0% and 74.2% and 96.6% at 6 months and 1 year, respectively. Stratified for the treatment strategy (PTA alone in 79, PTA with stenting in 300 patients, and excimer laser in 64), 1-year primary patency rates were 68.6%, 75.5%, and 75.4%, whereas the limb salvage rates were 96.7%, 98.6%, and 87.9% for each modality, respectively. Endovascular intervention will become the primary treatment for BTK lesions in patients with critical limb ischemia, with 1-year primary patency and limb salvage rates that compare favorably with published surgical data. Prospective, randomized, multicenter trials will be needed to further establish the role of endovascular intervention in this challenging patient group.

  14. Nonoperative active management of critical limb ischemia: initial experience using a sequential compression biomechanical device for limb salvage.

    LENUS (Irish Health Repository)

    Sultan, Sherif

    2008-01-01

    Critical limb ischemia (CLI) patients are at high risk of primary amputation. Using a sequential compression biomechanical device (SCBD) represents a nonoperative option in threatened limbs. We aimed to determine the outcome of using SCBD in amputation-bound nonreconstructable CLI patients regarding limb salvage and 90-day mortality. Thirty-five patients with 39 critically ischemic limbs (rest pain = 12, tissue loss = 27) presented over 24 months. Thirty patients had nonreconstructable arterial outflow vessels, and five were inoperable owing to severe comorbidity scores. All were Rutherford classification 4 or 5 with multilevel disease. All underwent a 12-week treatment protocol and received the best medical treatment. The mean follow-up was 10 months (SD +\\/- 6 months). There were four amputations, with an 18-month cumulative limb salvage rate of 88% (standard error [SE] +\\/- 7.62%). Ninety-day mortality was zero. Mean toe pressures increased from 38.2 to 67 mm Hg (SD +\\/- 33.7, 95% confidence interval [CI] 55-79). Popliteal artery flow velocity increased from 45 to 47.9 cm\\/s (95% CI 35.9-59.7). Cumulative survival at 12 months was 81.2% (SE +\\/- 11.1) for SCBD, compared with 69.2% in the control group (SE +\\/- 12.8%) (p = .4, hazards ratio = 0.58, 95% CI 0.15-2.32). The mean total cost of primary amputation per patient is euro29,815 ($44,000) in comparison with euro13,900 ($20,515) for SCBD patients. SCBD enhances limb salvage and reduces length of hospital stay, nonoperatively, in patients with nonreconstructable vessels.

  15. Primary motor cortex changes after amputation correlate with phantom limb pain and the ability to move the phantom limb.

    Science.gov (United States)

    Raffin, Estelle; Richard, Nathalie; Giraux, Pascal; Reilly, Karen T

    2016-04-15

    A substantial body of evidence documents massive reorganization of primary sensory and motor cortices following hand amputation, the extent of which is correlated with phantom limb pain. Many therapies for phantom limb pain are based upon the idea that plastic changes after amputation are maladaptive and attempt to normalize representations of cortical areas adjacent to the hand area. Recent data suggest, however, that higher levels of phantom pain are associated with stronger local activity and more structural integrity in the missing hand area rather than with reorganization of neighbouring body parts. While these models appear to be mutually exclusive they could co-exist, and one reason for the apparent discrepancy between them might be that no single study has examined the organisation of lip, elbow, and hand movements in the same participants. In this study we thoroughly examined the 3D anatomy of the central sulcus and BOLD responses during movements of the hand, elbow, and lips using MRI techniques in 11 upper-limb amputees and 17 healthy control subjects. We observed different reorganizational patterns for all three body parts as the former hand area showed few signs of reorganization, but the lip and elbow representations reorganized and shifted towards the hand area. We also found that poorer voluntary control and higher levels of pain in the phantom limb were powerful drivers of the lip and elbow topological changes. In addition to providing further support for the maladaptative plasticity model, we demonstrate for the first time that motor capacities of the phantom limb correlate with post-amputation reorganization, and that this reorganization is not limited to the face and hand representations but also includes the proximal upper-limb.

  16. Text Classification using Artificial Intelligence

    CERN Document Server

    Kamruzzaman, S M

    2010-01-01

    Text classification is the process of classifying documents into predefined categories based on their content. It is the automated assignment of natural language texts to predefined categories. Text classification is the primary requirement of text retrieval systems, which retrieve texts in response to a user query, and text understanding systems, which transform text in some way such as producing summaries, answering questions or extracting data. Existing supervised learning algorithms for classifying text need sufficient documents to learn accurately. This paper presents a new algorithm for text classification using artificial intelligence technique that requires fewer documents for training. Instead of using words, word relation i.e. association rules from these words is used to derive feature set from pre-classified text documents. The concept of na\\"ive Bayes classifier is then used on derived features and finally only a single concept of genetic algorithm has been added for final classification. A syste...

  17. Artificial intelligence and science education

    Science.gov (United States)

    Good, Ron

    Artificial intelligence (AI) is defined and related to intelligent computer-assisted instruction (ICAI) and science education. Modeling the student, the teacher, and the natural environment are discussed as important parts of ICAI and the concept of microworlds as a powerful tool for science education is presented. Optimistic predictions about ICAI are tempered with the complex, persistent problems of: 1) teaching and learning as a soft or fuzzy knowledge base, 2) natural language processing, and 3) machine learning. The importance of accurate diagnosis of a student's learning state, including misconceptions and naive theories about nature, is stressed and related to the importance of accurate diagnosis by a physician. Based on the cognitive science/AI paradigm, a revised model of the well-known Karplus/Renner learning cycle is proposed.

  18. Innovative applications of artificial intelligence

    Science.gov (United States)

    Schorr, Herbert; Rappaport, Alain

    Papers concerning applications of artificial intelligence are presented, covering applications in aerospace technology, banking and finance, biotechnology, emergency services, law, media planning, music, the military, operations management, personnel management, retail packaging, and manufacturing assembly and design. Specific topics include Space Shuttle telemetry monitoring, an intelligent training system for Space Shuttle flight controllers, an expert system for the diagnostics of manufacturing equipment, a logistics management system, a cooling systems design assistant, and a knowledge-based integrated circuit design critic. Additional topics include a hydraulic circuit design assistant, the use of a connector assembly specification expert system to harness detailed assembly process knowledge, a mixed initiative approach to airlift planning, naval battle management decision aids, an inventory simulation tool, a peptide synthesis expert system, and a system for planning the discharging and loading of container ships.

  19. Apartes desde la inteligencia artificial

    Directory of Open Access Journals (Sweden)

    Luis Carlos Torres Soler

    2011-01-01

    Full Text Available El estudio y desarrollo de la inteligencia artificial no debe centrarse sólo en la creación de software o hardware que permita realizar procesos algorítmicos o heurísticos en el computador, de tal forma que produzcan soluciones óptimas y eficientes al resolver un problema complejo, ya sea de manejo de información o de toma de decisiones, o crear máquinas que tengan buena apariencia del ser humano; se debe, sobre todo, analizar la parte neurológica y sicológica que presenta el individuo al solucionar problemas. Además, es importante conocer la capacidad intelectual de la persona, de ahí la variedad de carreras profesionales que existen; no puede quedar por fuera de los sistemas inteligentes la concepción del amor o admiración.

  20. Artificial intelligence in medical diagnosis.

    Science.gov (United States)

    Szolovits, P; Patil, R S; Schwartz, W B

    1988-01-01

    In an attempt to overcome limitations inherent in conventional computer-aided diagnosis, investigators have created programs that simulate expert human reasoning. Hopes that such a strategy would lead to clinically useful programs have not been fulfilled, but many of the problems impeding creation of effective artificial intelligence programs have been solved. Strategies have been developed to limit the number of hypotheses that a program must consider and to incorporate pathophysiologic reasoning. The latter innovation permits a program to analyze cases in which one disorder influences the presentation of another. Prototypes embodying such reasoning can explain their conclusions in medical terms that can be reviewed by the user. Despite these advances, further major research and developmental efforts will be necessary before expert performance by the computer becomes a reality.

  1. Artificial Limb Recovery after Tramatic Amputation%创伤截肢后的假肢康复

    Institute of Scientific and Technical Information of China (English)

    焦绍锋; 王振军; 张晓玉

    2008-01-01

    5.12汶川地震使当地许多伤员肢体残缺,对伤者的生理和心理产生了重大的影响.帮助这些伤员尽快走出阴影.使他们在灾后能够最大程度的身心康复,重新回归社会,假肢的装配和使用是目前最有效的方法.为了使假肢能够更好地替代残缺肢体的功能,应当从截肢前着手,包括患者截肢平面的选择、残端的正确处理.术后早期对患者进行功能锻炼指导,防止畸形发生,尽可能早地根据患者自身情况选配合适的假肢,并指导患者正确使用和维护假肢,使其能够成功地回归社会,增强截肢者生活的信心.

  2. Biological artificial vessel graft in distal arterial bypass for treating diabetic lower limb ischemia: a case report

    Institute of Scientific and Technical Information of China (English)

    GU Yong-quan; WU Ying-feng; QI Li-xing; GUO Lian-ri; LI Xue-feng; CUI Shi-jun; TONG Zhu; GUO Jian-ming; ZHANG Jian

    2011-01-01

    A 68-year-old female patient was treated for unhealed ulcer in the fourth toe of the left foot. Clinical examinations identified severe stenosis of the proximal segment and occlusion of the distal segment of the left anterior tibial artery, and occlusion of the left posterior tibial artery and the peroneal artery. The proximal stenotic segment of the left anterior tibial artery was dilated, but the distal occlusive part failed to be re-canalized. Left anterior tibial artery to dorsal pedal artery bypass was performed on the patient with an epoxide-crosslinked, special radicals antigen-sealed, porcine-derived biological graft; debridement of the left 4th digiti pedis was also performed. Postoperation course was uneventful. The pulse of the left dorsal pedal artery was strong. The ankle brachial index (ABI) increased from 0.60 to 1.09. Warfarin and two antiplatelet drugs were given after the operation. Six months after operation, computed tomographic angiogram (CTA)identified the patent graft.

  3. Web Intelligence and Artificial Intelligence in Education

    Science.gov (United States)

    Devedzic, Vladan

    2004-01-01

    This paper surveys important aspects of Web Intelligence (WI) in the context of Artificial Intelligence in Education (AIED) research. WI explores the fundamental roles as well as practical impacts of Artificial Intelligence (AI) and advanced Information Technology (IT) on the next generation of Web-related products, systems, services, and…

  4. The artificial pancreas : From logic to life

    NARCIS (Netherlands)

    Kropff, J.

    2017-01-01

    In this thesis we investigated the efficacy of real-life use of an artificial pancreas starting with use of these systems in a hotel setting and finally 24/7 long-term use at home. We investigated the accuracy of continuous glucose monitoring (CGM) systems that act as input for the artificial pancre

  5. 50 CFR 27.73 - Artificial lights.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Artificial lights. 27.73 Section 27.73 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE... Artificial lights. No unauthorized person shall use or direct the rays of a spotlight or other...

  6. Creativity in design and artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Neocleous, C.C.; Esat, I.I. [Brunel Univ. Uxbridge (United Kingdom); Schizas, C.N. [Univ. of Cyprus, Nicosia (Cyprus)

    1996-12-31

    The creativity phase is identified as an integral part of the design phase. The characteristics of creative persons which are relevant to designing artificial neural networks manifesting aspects of creativity, are identified. Based on these identifications, a general framework of artificial neural network characteristics to implement such a goal are proposed.

  7. Artificial Intelligence--Applications in Education.

    Science.gov (United States)

    Poirot, James L.; Norris, Cathleen A.

    1987-01-01

    This first in a projected series of five articles discusses artificial intelligence and its impact on education. Highlights include the history of artificial intelligence and the impact of microcomputers; learning processes; human factors and interfaces; computer assisted instruction and intelligent tutoring systems; logic programing; and expert…

  8. Isolated Speech Recognition Using Artificial Neural Networks

    Science.gov (United States)

    2007-11-02

    In this project Artificial Neural Networks are used as research tool to accomplish Automated Speech Recognition of normal speech. A small size...the first stage of this work are satisfactory and thus the application of artificial neural networks in conjunction with cepstral analysis in isolated word recognition holds promise.

  9. Artificial Neural Networks and Instructional Technology.

    Science.gov (United States)

    Carlson, Patricia A.

    1991-01-01

    Artificial neural networks (ANN), part of artificial intelligence, are discussed. Such networks are fed sample cases (training sets), learn how to recognize patterns in the sample data, and use this experience in handling new cases. Two cognitive roles for ANNs (intelligent filters and spreading, associative memories) are examined. Prototypes…

  10. Airway Complications of Total Artificial Heart.

    Science.gov (United States)

    Pathak, Vikas; Donovan, Colin; Malhotra, Rajiv

    2017-02-01

    The total artificial heart is the mechanical device which is used as a bridge to the heart transplant in patients with biventricular failure. Due to the mechanical nature of the device, patients receiving total artificial heart (TAH) require to be on anticoagulation therapy. Hemorrhage and coagulopathy are few of the known complications of TAH.

  11. Dynamic optimization of artificial lighting in greenhouses.

    NARCIS (Netherlands)

    Heuvelink, E.; Challa, H.

    1989-01-01

    A principle for dynamic optimization of artificial lighting in greenhouses is presented, where the optimization criterion is maximization of the term . To this purpose it is important to consider the break-even point for artificial lighting, which can be defined a

  12. Artificial Intelligence in Education: An Exploration.

    Science.gov (United States)

    Cumming, Geoff

    1998-01-01

    Gives a brief outline of the development of Artificial Intelligence in Education (AIED) which includes psychology, education, cognitive science, computer science, and artificial intelligence. Highlights include learning environments; learner modeling; a situated approach to learning; and current examples of AIED research. (LRW)

  13. [Transcutaneous osseointegrated prosthesis (TOP) after limb amputation : Status quo and perspectives].

    Science.gov (United States)

    Willy, Christian; Krettek, Christian

    2017-04-10

    The majority of transfemoral and transtibial amputees can be functionally fitted with conventional suspension sockets; however, due to socket problems using conventional stump care, 60% of the patients have limited function and even in younger patients approximately one sixth are unable to wear the prosthesis daily. After the introduction of transcutaneous osseointegrated prostheses (TOP) the inherent problems of socket-stump care can be avoided for these patients. Against this background this article reviews the recent clinical development of TOP in Sweden, Germany, the Netherlands, Australia and USA currently in nine centers. Unanimously, all groups show that TOP enables physiological weight bearing, improved range of motion in the proximal joint, as well as osseoperceptive sensory feedback and better control of the artificial limb. Likewise, there is agreement that as a rule that there is a clinically less relevant superficial contamination of the stoma. Furthermore, TOP is nowadays also used for transhumeral amputees and after thumb amputation and the development of the indications for this technique are increasing. Future aspects include novel treatment options using implanted intramedullary electrodes allowing permanent and unlimited bidirectional communication with the human body (osseointegrated human-machine gateway). This could possibly realize an innovative form of prosthesis control as well as the combination of TOP and targeted muscle reinnervation (TMR) surgery to create more advanced prosthesis systems for upper and lower extremity amputees.

  14. Development of an Environment-Aware Locomotion Mode Recognition System for Powered Lower Limb Prostheses.

    Science.gov (United States)

    Liu, Ming; Wang, Ding; Helen Huang, He

    2016-04-01

    This paper aimed to develop and evaluate an environment-aware locomotion mode recognition system for volitional control of powered artificial legs. A portable terrain recognition (TR) module, consisting of an inertia measurement unit and a laser distance meter, was built to identify the type of terrain in front of the wearer while walking. A decision tree was used to classify the terrain types and provide either coarse or refined information about the walking environment. Then, the obtained environmental information was modeled as a priori probability and was integrated with a neuromuscular-mechanical-fusion-based locomotion mode (LM) recognition system. The designed TR module and environmental-aware LM recognition system was evaluated separately on able-bodied subjects and a transfemoral amputee online. The results showed that the TR module provided high quality environmental information: TR accuracy is above 98% and terrain transitions are detected over 500 ms before the time required to switch the prosthesis control mode. This enabled smooth locomotion mode transitions for the wearers. The obtained environmental information further improved the performance of LM recognition system, regardless of whether coarse or refined information was used. In addition, the environment-aware LM recognition system produced reliable online performance when the TR output was relatively noisy, which indicated the potential of this system to operate in unconstructed environment. This paper demonstrated that environmental information should be considered for operating wearable lower limb robotic devices, such as prosthetics and orthotics.

  15. Preliminary Evaluation of Intelligent Intention Estimation Algorithms for an Actuated Lower-Limb Exoskeleton

    Directory of Open Access Journals (Sweden)

    Mervin Chandrapal

    2013-02-01

    Full Text Available This paper describes the experimental testing of an actuated lower-limb exoskeleton. The exoskeleton is designed to alleviate the loading at the knee joint by supplying assistive torque. It is hypothesized that the support provided will reduce the muscular effort required to perform activities of daily living and thus facilitate the execution of these movements by those who previously had limited mobility. The exoskeleton is actuated by four pneumatic artificial muscles, each providing 150N of pulling force to assist in the flexion and extension of the knee joint. The exoskeleton system estimates the user’s intended motion using muscle activity information recorded from five thigh muscles, together with the knee angle. To experimentally evaluate the performance of the device, the exoskeleton was worn by an able-bodied user, whilst performing the sit-to-stand-to-sit movement. In addition, the three intention estimation algorithms were also tested to determine the influence of the various algorithms on the support provided. The results show a significant reduction in the user’s muscle activity (≈ 20% when assisted by the exoskeleton in a predictable manner.

  16. Biofluid lubrication for artificial joints

    Science.gov (United States)

    Pendleton, Alice Mae

    This research investigated biofluid lubrication related to artificial joints using tribological and rheological approaches. Biofluids studied here represent two categories of fluids, base fluids and nanostructured biofluids. Base fluids were studied through comparison of synthetic fluids (simulated body fluid and hyaluronic acid) as well as natural biofluids (from dogs, horses, and humans) in terms of viscosity and fluid shear stress. The nano-structured biofluids were formed using molecules having well-defined shapes. Understanding nano-structured biofluids leads to new ways of design and synthesis of biofluids that are beneficial for artificial joint performance. Experimental approaches were utilized in the present research. This includes basic analysis of biofluids' property, such as viscosity, fluid shear stress, and shear rate using rheological experiments. Tribological investigation and surface characterization were conducted in order to understand effects of molecular and nanostructures on fluid lubrication. Workpiece surface structure and wear mechanisms were investigated using a scanning electron microscope and a transmission electron microscope. The surface topography was examined using a profilometer. The results demonstrated that with the adding of solid additives, such as crown ether or fullerene acted as rough as the other solids in the 3-body wear systems. In addition, the fullerene supplied low friction and low wear, which designates the lubrication purpose of this particular particle system. This dissertation is constructed of six chapters. The first chapter is an introduction to body fluids, as mentioned earlier. After Chapter II, it examines the motivation and approach of the present research, Chapter III discusses the experimental approaches, including materials, experimental setup, and conditions. In Chapter IV, lubrication properties of various fluids are discussed. The tribological properties and performance nanostructured biofluids are

  17. A DISTRIBUTED SMART HOME ARTIFICIAL INTELLIGENCE SYSTEM

    DEFF Research Database (Denmark)

    Lynggaard, Per

    2013-01-01

    A majority of the research performed today explore artificial intelligence in smart homes by using a centralized approach where a smart home server performs the necessary calculations. This approach has some disadvantages that can be overcome by shifting focus to a distributed approach where...... the artificial intelligence system is implemented as distributed as agents running parts of the artificial intelligence system. This paper presents a distributed smart home architecture that distributes artificial intelligence in smart homes and discusses the pros and cons of such a concept. The presented...... distributed model is a layered model. Each layer offers a different complexity level of the embedded distributed artificial intelligence. At the lowest layer smart objects exists, they are small cheap embedded microcontroller based smart devices that are powered by batteries. The next layer contains a more...

  18. Reinforcement Learning Based Artificial Immune Classifier

    Directory of Open Access Journals (Sweden)

    Mehmet Karakose

    2013-01-01

    Full Text Available One of the widely used methods for classification that is a decision-making process is artificial immune systems. Artificial immune systems based on natural immunity system can be successfully applied for classification, optimization, recognition, and learning in real-world problems. In this study, a reinforcement learning based artificial immune classifier is proposed as a new approach. This approach uses reinforcement learning to find better antibody with immune operators. The proposed new approach has many contributions according to other methods in the literature such as effectiveness, less memory cell, high accuracy, speed, and data adaptability. The performance of the proposed approach is demonstrated by simulation and experimental results using real data in Matlab and FPGA. Some benchmark data and remote image data are used for experimental results. The comparative results with supervised/unsupervised based artificial immune system, negative selection classifier, and resource limited artificial immune classifier are given to demonstrate the effectiveness of the proposed new method.

  19. EFFECTS OF ETHANOL AND HYDROGEN PEROXIDE ON MOUSE LIMB BUD MESENCHYME DIFFERENTIATION AND CELL DEATH

    Science.gov (United States)

    Many of the morphological defects associated with embryonic alcohol exposure are a result of cell death. During limb development, ethanol administration produces cell death in the limb and digital defects, including postaxial ectrodactyly. Because an accumulation of reactive oxyg...

  20. Collagen reconstitution is inversely correlated with induction of limb regeneration in Ambystoma mexicanum.

    Science.gov (United States)

    Satoh, Akira; Hirata, Ayako; Makanae, Aki

    2012-03-01

    Amphibians can regenerate missing body parts, including limbs. The regulation of collagen has been considered to be important in limb regeneration. Collagen deposition is suppressed during limb regeneration, so we investigated collagen deposition and apical epithelial cap (AEC) formation during axolotl limb regeneration. The accessory limb model (ALM) has been developed as an alternative model for studying limb regeneration. Using this model, we investigated the relationship between nerves, epidermis, and collagen deposition. We found that Sp-9, an AEC marker gene, was upregulated by direct interaction between nerves and epidermis. However, collagen deposition hindered this interaction, and resulted in the failure of limb regeneration. During wound healing, an increase in deposition of collagen caused a decrease in the blastema induction rate in ALM. Wound healing and limb regeneration are alternate processes.

  1. Functional recovery of the paretic upper limb after stroke: who regains hand capacity?

    NARCIS (Netherlands)

    Houwink, A.; Nijland, R.H.; Geurts, A.C.H.; Kwakkel, G.

    2013-01-01

    OBJECTIVE: To describe recovery of upper limb capacity after stroke during inpatient rehabilitation based on the Stroke Upper Limb Capacity Scale (SULCS). DESIGN: Prospective observational study. SETTING: Inpatient department of a rehabilitation center. PARTICIPANTS: Patients with stroke (N=299) adm

  2. Objective Assessment of Upper-Limb Mobility for Poststroke Rehabilitation.

    Science.gov (United States)

    Zhang, Zhe; Fang, Qiang; Gu, Xudong

    2016-04-01

    The assessment of the limb mobility of stroke patients is an essential part of poststroke rehabilitation. Conventionally, the assessment is manually performed by clinicians using chart-based ordinal scales, which can be subjective and inefficient. By introducing quantitative evaluation measures, the sensitivity and efficiency of the assessment process can be significantly improved. In this paper, a novel single-index-based assessment approach for quantitative upper-limb mobility evaluation has been proposed for poststroke rehabilitation. Instead of the traditional human-observation-based measures, the proposed assessment system utilizes the kinematic information automatically collected during a regular rehabilitation training exercise using a wearable inertial measurement unit. By calculating a single index, the system can efficiently generate objective and consistent quantitative results that can reflect the stroke patient's upper-limb mobility. In order to verify and validate the proposed assessment system, experiments have been conducted using 145 motion samples collected from 21 stroke patients (12 males, nine females, mean age 58.7±19.3) and eight healthy participants. The results have suggested that the proposed assessment index can not only differentiate the levels of limb function impairment clearly (p Brunnstrom stages of recovery (r = 0.86, p Brunnstrom stage classification application with an 82.1% classification accuracy, while using a K-nearest-neighbor classifier.

  3. Diagnostic distribution of non-traumatic upper limb disorders

    DEFF Research Database (Denmark)

    Laursen, Lise H; Sjøgaard, Gisela; Hagert, C G

    2007-01-01

    BACKGROUND: Upper limb disorders (ULDs) are common, and so are the difficulties in specific diagnoses of these disorders. Prior studies have shed light on the nerves in the diagnostic approach beside disorders related to muscles, tendons and joints (MCDs). OBJECTIVE: The study aimed to compare th...

  4. Popliteo-pedal bypass surgery for critical limb ischemia.

    LENUS (Irish Health Repository)

    Good, D W

    2011-12-01

    Critical limb ischaemia due to distal arterial disease represents a significant challenge. Randomised controlled evidence suggests that open surgery may be superior to endovascular intervention but there is limited data on the specific clinical cohort with exclusively infra-popliteal disease.

  5. Lower limb fractures associated with multiligament knee injury

    Science.gov (United States)

    Stagnaro, Joaquin; Yacuzzi, Carlos; Barla, Jorge; Zicaro, Juan Pablo; Costa-Paz, Matias

    2017-01-01

    Objectives: Knee ligament injuries related to lower limb fractures are common and frequently unnoticed. Management of acute polytrauma is usually focused in the bone lesion and a complete physical examination might be really difficult. The purpose of this study was to analyze a series of patients who suffered multiligament knee injuries associated to a lower limb fracture. Hypothesis: The use of magnetic resonance imaging (MRI) during the initial management can lead to an early diagnosis of ligament injuries. Methods: A retrospective search was conducted from our hospital´s electronic database. We evaluated the initial diagnosis and acute surgical treatment, and management and functional outcomes after the ligament lesion was diagnosed. Results: Seven patients who presented a knee multiligament injury associated with a lower limb fracture were evaluated. The average age was 29 years. Primary diagnoses were: four tibial plateau fractures; one open fracture-dislocation of the knee; one open leg fracture and ipsilateral hip dislocation; and one bifocal femur fracture. Only three patients had an MRI during the initial management of trauma. Six out of seven patients had to be operated on for the multiligament knee injury. The period between the resolution of the fracture and the ligamentous repair was from 3 to 24 months. Conclusion: Poor functional outcomes are reported in patients with multiligament knee injuries associated with high-energy lower limb fractures. We consider an MRI during the initial management can lead to better outcomes. A trauma surgeon working alongside an arthroscopic surgeon might optimize the results for these lesions.

  6. Vocational reintegration after a lower limb amputation: A qualitative study

    NARCIS (Netherlands)

    Bruins, Ria; Bruins, M.; Geertzen, J.H.B.; Groothoff, J.W.; Schoppen, T.

    2003-01-01

    The objectives of this study were to describe the process of job reintegration, to obtain more detailed information about workplace adjustments, and to assess the positive and negative experiences of amputees (in the Netherlands) who returned to paid work after their lower limb amputation. The study

  7. Somatic and movement inductions phantom limb in non-amputees

    Science.gov (United States)

    Casas, D. M.; Gentiletti, G. G.; Braidot, A. A.

    2016-04-01

    The illusion of the mirror box is a tool for phantom limb pain treatment; this article proposes the induction of phantom limb syndrome on non-amputees upper limb, with a neurological trick of the mirror box. With two study situations: a) Somatic Induction is a test of the literature reports qualitatively, and novel proposal b) Motor Induction, which is an objective report by recording surface EEG. There are 3 cases proposed for Motor illusion, for which grasped movement is used: 1) Control: movement is made, 2) illusion: the mirror box is used, and 3) Imagination: no movement is executed; the subject only imagines its execution. Three different tasks are registered for each one of them (left hand, right hand, and both of them). In 64% of the subjects for somatic experience, a clear response to the illusion was observed. In the experience of motor illusion, cortical activation is detected in both hemispheres of the primary motor cortex during the illusion, where the hidden hand remains motionless. These preliminary findings in phantom limb on non-amputees can be a tool for neuro-rehabilitation and neuro-prosthesis control training.

  8. Thermographic patterns of the upper and lower limbs: baseline data.

    Science.gov (United States)

    Gatt, Alfred; Formosa, Cynthia; Cassar, Kevin; Camilleri, Kenneth P; De Raffaele, Clifford; Mizzi, Anabelle; Azzopardi, Carl; Mizzi, Stephen; Falzon, Owen; Cristina, Stefania; Chockalingam, Nachiappan

    2015-01-01

    Objectives. To collect normative baseline data and identify any significant differences between hand and foot thermographic distribution patterns in a healthy adult population. Design. A single-centre, randomized, prospective study. Methods. Thermographic data was acquired using a FLIR camera for the data acquisition of both plantar and dorsal aspects of the feet, volar aspects of the hands, and anterior aspects of the lower limbs under controlled climate conditions. Results. There is general symmetry in skin temperature between the same regions in contralateral limbs, in terms of both magnitude and pattern. There was also minimal intersubject temperature variation with a consistent temperature pattern in toes and fingers. The thumb is the warmest digit with the temperature falling gradually between the 2nd and the 5th fingers. The big toe and the 5th toe are the warmest digits with the 2nd to the 4th toes being cooler. Conclusion. Measurement of skin temperature of the limbs using a thermal camera is feasible and reproducible. Temperature patterns in fingers and toes are consistent with similar temperatures in contralateral limbs in healthy subjects. This study provides the basis for further research to assess the clinical usefulness of thermography in the diagnosis of vascular insufficiency.

  9. Thermographic Patterns of the Upper and Lower Limbs: Baseline Data

    Directory of Open Access Journals (Sweden)

    Alfred Gatt

    2015-01-01

    Full Text Available Objectives. To collect normative baseline data and identify any significant differences between hand and foot thermographic distribution patterns in a healthy adult population. Design. A single-centre, randomized, prospective study. Methods. Thermographic data was acquired using a FLIR camera for the data acquisition of both plantar and dorsal aspects of the feet, volar aspects of the hands, and anterior aspects of the lower limbs under controlled climate conditions. Results. There is general symmetry in skin temperature between the same regions in contralateral limbs, in terms of both magnitude and pattern. There was also minimal intersubject temperature variation with a consistent temperature pattern in toes and fingers. The thumb is the warmest digit with the temperature falling gradually between the 2nd and the 5th fingers. The big toe and the 5th toe are the warmest digits with the 2nd to the 4th toes being cooler. Conclusion. Measurement of skin temperature of the limbs using a thermal camera is feasible and reproducible. Temperature patterns in fingers and toes are consistent with similar temperatures in contralateral limbs in healthy subjects. This study provides the basis for further research to assess the clinical usefulness of thermography in the diagnosis of vascular insufficiency.

  10. Lymphangiectasis of lower limb: A rare challenging case

    Directory of Open Access Journals (Sweden)

    Bhattacharya Visweswar

    2009-01-01

    Full Text Available Lymphangiectasis usually occurs in the viscera. Involvement of the lower limb is very rare. It is difficult to establish the diagnosis without detailed investigations. Clinical features are peculiar and may mimic lymphoedema of different origins which needs to be ruled out. Contrary to the expectation, the post-operative result is excellent in the long-term follow-up.

  11. Limb-nadir matching using non-coincident NO

    NARCIS (Netherlands)

    Adams, Cristen; Normand, Elise N.; McLinden, Chris A.; Bourassa, Adam E.; Lloyd, Nicholas D.; Degenstein, Douglas A.; Krotkov, Nickolay A.; Belmonte Rivas, Maria; Boersma, Folkert; Eskes, Henk

    2016-01-01

    A variant of the limb-nadir matching technique for deriving tropospheric NO2 columns is presented in which the stratospheric component of the NO2 slant column density (SCD) measured by the Ozone Monitoring Instrument (OMI) is removed using non-coincident profiles from the Op

  12. Functional protein networks unifying limb girdle muscular dystrophy

    NARCIS (Netherlands)

    Morrée, Antoine de

    2011-01-01

    Limb Girdle Muscular Dystrophy (LGMD) is a rare progressive heterogeneous disorder that can be caused by mutations in at least 21 different genes. These genes are often widely expressed and encode proteins with highly differing functions. And yet mutations in all of them give rise to a similar clini

  13. Improving energy efficiency in robot limbs through hydraulic dangle

    Science.gov (United States)

    Whitman, Julian S.; Meller, Mike; Garcia, Ephrahim

    2015-03-01

    Animals often allow their limbs to swing passively under their own inertia. For example, about 40% of a human walking gait consists of the primarily passive swing phase. Current hydraulic robots employ traditional actuation methods in which fluid power is expended for all limb movements, even when passive dynamics could be utilized. "Dangle" is the ability to allow a hydraulic actuator to freely sway in response to external loads, in which both sides of the actuator are disconnected from pressure and connected to the tank. Dangle offers the opportunity for efficiency gains by enabling the use of momentum, gravity, and external loads to move a limb without expending fluid power. To demonstrate these efficiency gains, this paper presents an experiment that compares the fluid power consumed to actuate a two degree of freedom hydraulic leg following a human walking gait cycle trajectory in both a traditional manner and utilizing dangle. It was shown that the use of dangle can decrease fluid power consumption by 20% by utilizing pendular dynamics during the swing phase. At speeds higher than the free dangling rate, more power must be used to maintain the desired trajectory due to damping inherent in the configuration. The use of dangle as a power saving method when driving hydraulic limbs could increase operation time for untethered hydraulic walking robots.

  14. A short overview of upper limb rehabilitation devices

    Science.gov (United States)

    Macovei, S.; Doroftei, I.

    2016-08-01

    As some studies show, the number of people over 65 years old increases constantly, leading to the need of solution to provide services regarding patient mobility. Diseases, accidents and neurologic problems affect hundreds of people every day, causing pain and lost of motor functions. The ability of using the upper limb is indispensable for a human being in everyday activities, making easy tasks like drinking a glass of water a real challenge. We can agree that physiotherapy promotes recovery, but not at an optimal level, due to limited financial and human resources. Hence, the need of robot-assisted rehabilitation emerges. A robot for upper-limb exercises should have a design that can accurately control interaction forces and progressively adapt assistance to the patients’ abilities and also to record the patient's motion and evolution. In this paper a short overview of upper limb rehabilitation devices is presented. Our goal is to find the shortcomings of the current developed devices in terms of utility, ease of use and costs, for future development of a mechatronic system for upper limb rehabilitation.

  15. Core muscle activation during dynamic upper limb exercises in women.

    Science.gov (United States)

    Tarnanen, Sami P; Siekkinen, Kirsti M; Häkkinen, Arja H; Mälkiä, Esko A; Kautiainen, Hannu J; Ylinen, Jari J

    2012-12-01

    Although several everyday functions and sporting activities demand controlled use of the abdominal and back muscles while working with the upper limbs, the activity of core muscles during dynamic upper limb exercises in the standing position has not been studied extensively. The purpose of this cross-sectional study was to examine abdominal and back muscle activity during dynamic upper limb exercises while standing and to evaluate whether dynamic exercises are appropriate for strengthening muscles. The activation of the rectus abdominis, obliquus externus abdominis, longissimus, and multifidus muscles during dynamic bilateral or unilateral shoulder exercises with or without fixation of the pelvis was measured in 20 healthy women using surface electromyography. Trunk muscle activation during isometric maximum contraction was used as a comparative reference. With bilateral shoulder extension and unilateral shoulder horizontal adduction, abdominal muscle activity was >60% of activity during reference exercises. With unilateral shoulder horizontal abduction and shoulder extension exercises, back muscle activity was >60% of the activity level reference exercise. Muscle activation levels were 35-64% lower during shoulder horizontal adduction and abduction without fixation compared with exercises with fixation. The results indicate that upper limb exercises performed in the standing position are effective for activating core muscles. Bilateral and unilateral shoulder extension and unilateral shoulder horizontal abduction and adduction with the pelvis fixed elicited the greatest activity of the core muscles.

  16. Limb trauma in a university teaching hospital setting

    Directory of Open Access Journals (Sweden)

    I C Nwagbara

    2011-01-01

    Conclusion Majority of the limb trauma cases were as a result of road traffic crashes; thus efforts should be directed at improving safety on our roads to reduce the burden of trauma on the health care system. There is also a need to create awareness in the community on the role of orthodox medicine in the management of fractures.

  17. Revisions of endoprosthetic reconstructions after limb salvage in musculoskeletal oncology

    NARCIS (Netherlands)

    Renard, AJS; Veth, RPH; Schreuder, HWB; van Horn, J; Keller, A; Schraffordt Koops, H.

    1998-01-01

    Of 91 limb-salvage procedures using prosthetic reconstructions because of primary or metastatic bone and soft-tissue tumors 26 revisions were performed in 16 patients. Revision was due to polyethylene wear (9 cases), aseptic loosening (8 cases), recurrent hip dislocation (3 cases), prosthetic stem f

  18. Stump sensibility in children with upper limb reduction deficiency

    NARCIS (Netherlands)

    Reinkingh, Marianne; Reinders-Messelink, Heleen A.; Dijkstra, Pieter U.; Maathuis, Karel G. B.; van der Sluis, Corry K.

    2014-01-01

    Objectives: To compare stump sensibility in children with upper limb reduction deficiency with sensibility of the unaffected arm and hand. In addition, to evaluate the associations between stump sensibility, stump length and activity level. Design: Cross-sectional study. Subjects: Children and young

  19. Lower limb pain in sympathetic-sensory coupling

    Institute of Scientific and Technical Information of China (English)

    Hongjun Yang; Kairun Peng; Sanjue Hu; Li Xuan

    2011-01-01

    Previous studies have shown that sympathetic nerves are related to certain types of pain, and this phenomenon is referred to as sympathetic-sensory coupling. Chronic pain resulting from nerve injury can be exacerbated by sympathetic stimulation or relieved by sympathetic inhibition. In the present study, the correlation between pain and sympathetic nerves was analyzed in patients with severe pain in lower limbs, as well as in a chronically compressed dorsal root ganglion (CCD) rat model (model of low back pain and sciatica). Patients with severe pain in the lower limbs underwent chemical lumbar sympathectomy (CLS), and the analgesic effects of CLS were compared with painkillers. Results demonstrated significantly relieved lower limb pain following CLS, and the analgesic effects of CLS were superior to those seen with painkillers. In the CCD rat model, dorsal root ganglion neuronal activity significantly increased as a result of electrical stimulation to the sympathetic nerves. These results suggest that sympathetic nerves are closely associated with pain and sympathetic-sensory coupling is likely in lower limb pain in both patients and rat models of CCD.

  20. Potential of Novel EPO Derivatives in Limb Ischemia

    Directory of Open Access Journals (Sweden)

    Dhiraj Joshi

    2012-01-01

    Full Text Available Erythropoietin (EPO has tissue-protective properties, but it increases the risk of thromboembolism by raising the haemoglobin concentration. New generation of EPO derivatives is tissue protective without the haematopoietic side effects. Preclinical studies have demonstrated their effectiveness and safety. This paper summarizes the development in EPO derivatives with emphasis on their potential use in critical limb ischaemia.

  1. Effect of FGFR inhibitors on chicken limb development.

    Science.gov (United States)

    Horakova, Dana; Cela, Petra; Krejci, Pavel; Balek, Lukas; Moravcova Balkova, Simona; Matalova, Eva; Buchtova, Marcela

    2014-10-01

    Fibroblast growth factor (FGF) signalling appears essential for the regulation of limb development, but a full complexity of this regulation remains unclear. Here, we addressed the effect of three different chemical inhibitors of FGF receptor tyrosine kinases (FGFR) on growth and patterning of the chicken wings. The inhibitor PD173074 caused shorter and thinner wing when using lower concentration. Microinjection of higher PD173074 concentrations (25 and 50 mmol/L) into the wing bud at stage 20 resulted in the development of small wing rudiment or the total absence of the wing. Skeletal analysis revealed the absence of the radius but not ulna, deformation of metacarpal bones and/or a reduction of digits. Treatment with PD161570 resembled the effects of PD173074. NF449 induced shortening and deformation of the developing wing with reduced autopodium. These malformed embryos mostly died at the stage HH25-29. PD173074 reduced chondrogenesis also in the limb micromass cultures together with early inhibition of cartilaginous nodule formation, evidenced by lack of sulphated proteoglycan and peanut agglutinin expression. The effect of FGFR inhibition on limb development observed here was unlikely mediated by excessive cell death as none of the inhibitors caused massive apoptosis at low concentrations. More probably, FGFR inhibition decreased both the proliferation and adhesion of mesenchymal chondroprogenitors. We conclude that FGFR signalling contributes to the regulation of the anterior-posterior patterning of zeugopod during chicken limb development.

  2. Work-Related Upper Limb Disorders: A Case Report

    Directory of Open Access Journals (Sweden)

    Zlatka Borisova Stoyneva

    2015-03-01

    Full Text Available In this study the complex interrelationship between physical factors, job stress, lifestyle and genetic factors on symptoms of work-related musculoskeletal disorders of the upper limbs is demonstrated by a case report and discussion of the literature. A 58 year old woman with long lasting complaints of the upper limbs with increasing intensity and duration, generalisation, combined with skin thickness, Raynaud’s phenomenon, joint disorders, arterial and pulmonary hypertension, metabolic lipid dysfunctions is presented. Occupational history proves continuous duration of service at a job with occupational physical static load with numerous repetitive monotonous systematic motions of fingers and hands as a weaver of Persian rugs followed by work at an automated loom and variable labour activities. Though the complaints dated since the time she was a manual weaver, the manifestations of generalized joint degenerative changes, system sclerosis with Raynaud’s phenomenon with similar upper extremities signs and symptoms discount upper limbs musculoskeletal disorder as caused only or mainly by occupational risk factors. The main principles and criteria for occupational diagnosis of musculoskeletal upper limb disorders and legislative requirements for their reglamentation are discussed.

  3. Vocational reintegration after a lower limb amputation : a qualitative study

    NARCIS (Netherlands)

    Bruins, M.; Geertzen, J.H.; Groothoff, J.W.; Schoppen, T.

    2003-01-01

    The objectives of this study were to describe the process of job reintegration, to obtain more detailed information about workplace adjustments, and to assess the positive and negative experiences of amputees (in the Netherlands) who returned to paid work after their lower limb amputation. The study

  4. Oculopharyngeal muscular dystrophy with limb girdle weakness as major complaint.

    NARCIS (Netherlands)

    Sluijs, B.M. van der; Hoefsloot, L.H.; Padberg, G.W.A.M.; Maarel, S.M. van der; Engelen, B.G.M. van

    2003-01-01

    This first description of the oculopharyngeal muscular dystrophy (OPMD) phenotype in Dutch patients shows that limb girdle weakness can occur early in the course of disease and can give the first and major complaint in OPMD patients. The aim of this study was to examine clinically, histologically an

  5. Macrophages are required for adult salamander limb regeneration.

    Science.gov (United States)

    Godwin, James W; Pinto, Alexander R; Rosenthal, Nadia A

    2013-06-04

    The failure to replace damaged body parts in adult mammals results from a muted growth response and fibrotic scarring. Although infiltrating immune cells play a major role in determining the variable outcome of mammalian wound repair, little is known about the modulation of immune cell signaling in efficiently regenerating species such as the salamander, which can regrow complete body structures as adults. Here we present a comprehensive analysis of immune signaling during limb regeneration in axolotl, an aquatic salamander, and reveal a temporally defined requirement for macrophage infiltration in the regenerative process. Although many features of mammalian cytokine/chemokine signaling are retained in the axolotl, they are more dynamically deployed, with simultaneous induction of inflammatory and anti-inflammatory markers within the first 24 h after limb amputation. Systemic macrophage depletion during this period resulted in wound closure but permanent failure of limb regeneration, associated with extensive fibrosis and disregulation of extracellular matrix component gene expression. Full limb regenerative capacity of failed stumps was restored by reamputation once endogenous macrophage populations had been replenished. Promotion of a regeneration-permissive environment by identification of macrophage-derived therapeutic molecules may therefore aid in the regeneration of damaged body parts in adult mammals.

  6. Principles of obstacle avoidance with a transfemoral prosthetic limb

    NARCIS (Netherlands)

    van Keeken, Helco G.; Vrieling, Aline H.; Hof, At L.; Postema, Klaas; Otten, Bert

    2012-01-01

    In this study, conditions that enable a prosthetic knee flexion strategy in transfemoral amputee subjects during obstacle avoidance were investigated. This study explored the hip torque principle and the static ground principle as object avoidance strategies. A prosthetic limb simulator device was u

  7. A study on limb reduction defects in six European regions

    NARCIS (Netherlands)

    Stoll, C; Calzolari, E; Cornel, M; GarciaMinaur, S; Garne, E; Nevin, N

    1996-01-01

    Limb reduction defects (LRD) gained especial attention after the thalidomide tragedy in 1962, LRD are common congenital malformations which present as obvious congenital anomalies recognized at birth, Therefore it might be assumed that they are well documented, However classification of LRDs is disp

  8. Limb distribution, motor impairment, and functional classification of cerebral palsy

    NARCIS (Netherlands)

    J.A. Gorter; P.L. Rosenbaum

    2004-01-01

    This study explored the relationships between the Gross Motor Function Classification System (GMFCS), limb distribution, and type of motor impairment. Data used were collected in the Ontario Motor Growth study, a longitudinal cohort study with a population-based sample of children with cerebral pals

  9. Geriatric rehabilitation of lower limb amputees: a multicenter study.

    NARCIS (Netherlands)

    Eijk, M.S. van; Linde, H. van der; Buijck, B.I.; Zuidema, S.U.; Koopmans, R.T.C.M.

    2012-01-01

    PURPOSE: The aim of this study was to determine factors independently associated with successful rehabilitation of patients with lower limb amputation in skilled nursing facilities (SNFs). METHODS: All patients admitted to one of the 11 participating SNFs were eligible. Multidisciplinary teams colle

  10. Geriatric rehabilitation of lower limb amputees : a multicenter study

    NARCIS (Netherlands)

    Eijk, Monica Spruit-van; van der Linde, Harmen; Buijck, Bianca I; Zuidema, Sytse U; Koopmans, Raymond T C M

    2012-01-01

    PURPOSE: The aim of this study was to determine factors independently associated with successful rehabilitation of patients with lower limb amputation in skilled nursing facilities (SNFs). METHODS: All patients admitted to one of the 11 participating SNFs were eligible. Multidisciplinary teams colle

  11. 7 CFR 51.2542 - U.S. Artificially Opened.

    Science.gov (United States)

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Pistachio Nuts in the Shell § 51.2542 U.S. Artificially Opened. “U.S. Artificially Opened” consists of artificially opened pistachio nuts in the shell which...

  12. Motor control and learning with lower-limb myoelectric control in amputees

    OpenAIRE

    2013-01-01

    Advances in robotic technology have recently enabled the development of powered lower-limb prosthetic limbs. A major hurdle in developing commercially successful powered prostheses is the control interface. Myoelectric signals are one way for prosthetic users to provide feedforward volitional control of prosthesis mechanics. The goal of this study was to assess motor learning in people with lower-limb amputation using proportional myoelectric control from residual-limb muscles. We examined in...

  13. Crossover replantation after bilateral traumatic lower limb amputations: a case report

    OpenAIRE

    Fang Jun; Li Huazhuang; Dou Honglei; Chen Jingchun; Xu Aiping; Liu Wenguo; Ding Gang

    2012-01-01

    Abstract Introduction Replantation of a limb to the contralateral stump after bilateral traumatic amputations is rare. To the best of our knowledge, there are only a few reports of crossover lower limb replantation in the literature. Case presentation We treated a 37-year-old Chinese woman with bilateral lower limb crush injuries sustained in a traffic accident. Her lower limb injuries were at different anatomic levels. We performed emergency bilateral amputations followed by crossover replan...

  14. Environmental monitoring for the DOE coolside and LIMB demonstration extension projects

    Energy Technology Data Exchange (ETDEWEB)

    White, T.; Contos, L.; Adams, L. (Radian Corp., Research Triangle Park, NC (United States). Progress Center)

    1992-02-01

    The purpose of this document is to present environmental monitoring data collected during the US DOE Limestone Injection Multistage Burner (LIMB) Demonstration Project Extension. The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2}) and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators. (VC)

  15. Artificial Means for Improving Human Motion

    Directory of Open Access Journals (Sweden)

    Diana Hodgins

    2004-01-01

    Full Text Available This paper gives a brief description of some of the key ongoing product developments in Europe for medical implants. A range of medical systems that are currently being developed under European-funded programmes are briefly described. The first is an implant that helps people with ‘dropped foot’ improve their walking. Further research on body-worn inertial measuring systems (IMUs and microsystems will extend the capabilities to other lower-limb and upper-limb applications in the future. Other medical systems being developed with the use of microsystems and nanotechnology include a system to aid deaf and blind people.

  16. Disorders of Upper Limb Movements in Ataxia-Telangiectasia.

    Directory of Open Access Journals (Sweden)

    Aasef G Shaikh

    Full Text Available Ataxia-telangiectasia is known for cerebellar degeneration, but clinical descriptions of abnormal tone, posture, and movements suggest involvement of the network between cerebellum and basal ganglia. We quantitatively assessed the nature of upper-limb movement disorders in ataxia-telangiectasia. We used a three-axis accelerometer to assess the natural history and severity of abnormal upper-limb movements in 80 ataxia-telangiectasia and 19 healthy subjects. Recordings were made during goal-directed movements of upper limb (kinetic task, while arms were outstretched (postural task, and at rest. Almost all ataxia-telangiectasia subjects (79/80 had abnormal involuntary movements, such as rhythmic oscillations (tremor, slow drifts (dystonia or athetosis, and isolated rapid movements (dystonic jerks or myoclonus. All patients with involuntary movements had both kinetic and postural tremor, while 48 (61% also had resting tremor. The tremor was present in transient episodes lasting several seconds during two-minute recording sessions of all three conditions. Percent time during which episodic tremor was present was greater for postural and kinetic tasks compared to rest. Resting tremor had higher frequency but smaller amplitude than postural and kinetic tremor. Rapid non-rhythmic movements were minimal during rest, but were triggered during sustained arm postures and goal directed arm movements suggesting they are best considered a form of dystonic jerks or action myoclonus. Advancing age did not correlate with the severity of involuntary limb movements. Abnormal upper-limb movements in ataxia-telangiectasia feature classic cerebellar impairment, but also suggest involvement of the network between the cerebellum and basal ganglia.

  17. Reoperations for occluded arterial bypasses in the lower limbs

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background We reviewed the outcomes of reoperations for 29 patients (30 limbs) who had undergone occluded arterial bypass in the lower limbs from May 1996 to September 2005. Methods The 30 lower limbs of the 29 patients with arteriosclerotic obstruction received 44 reoperations, including thrombectomy alone (group T, 27) and inflow or outflow reconstruction plus thrombectomy (group C, 17). Among the 17 operations in group C, 17.6% (3/17) were inflow reconstructions involving the axillary-femoral (1), aorta-iliac (1) and aorta-femoral (1) arteries, and 76.4% (13/17) outflow reconstructions involving the femoral-popliteal bypass-tibial (8), femoral-tibial (1), femoral-popliteal bypass-popliteal arteries below the knee (2), and the femoral-popliteal bypass-tibial-peroneal trunk (2). One patient (1 limb) underwent both inflow and outflow reconstructions with an iliac arterial stent and a graft-popliteal anastomosis patch. Polytetrafluoroethylene (PTFE) grafts were used in the inflow or outflow reconstructions abve the knee. Autovenous grafts or autovenously combined PTFE grafts were used in the outflow reconstructions below the knee. Results The percentages of Fontaine stage III and IV before primary operation and reoperation were 60% (18/30) and 86.7% (26/30), respectively (P0.05). Among 42 reoperations, 19 failed within 1 month in groups T (16) and C (3) (P0.05). The rate of limb salvage was 64.29% (18/28). Conclusions The percentages of Fontaine stage III and IV before reoperation may be much higher than those before primary operation. Thrombectomy plus inflow/outflow reconstruction creates patency better than thrombectomy alone for re-occluded bypass.

  18. Treatment of limb arterial in juries caused by traffic accidents

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective:To analyze the features,diagonosis and treatment of limb arterial injuries caused by traffic accidents.Methods:A total of 43 patients with limb arterial injury admitted in our department over the past 30years(about50%of them happened during the last10 years)were analyzed retrospectively in this article.The popliteal,femoral and brachial arteries were mainly involved,accounting for 432%,20.5%and20.5%respectively of all the involvements.There were 35cases of open injury and9of close injury,The involved vessels were transected in 43.2%of the cases and contused in 40.9%,All the patients had various complications,such as fractures,dislocations and severe soft tissue injuries.The injured vessels were repaired by means of end-to-end anastomosis in 10cases,autogenous vein graft in 23cases and intraluminal hydraulic dilatation in 4cases.Results:Successful limb salvage was achieved in 34cases initially,whereas10amputations were carried out due to injuries to popliteal arteries in7,femoral arteries in2and humeral artery in 1and severe soft tissue damages in9 cases.Twenty-nine patients were followed up for 1-156months,with the averageof48.8months.There was good circulation in 22 cases and certain ischemia in 5cases.Two amputations were carried out in the late stage because of popliteal artery thrombosis after repair in 2cases.There was no death in this series.Conclusions:The limb arterial injuries caused by traffic accidents are severe and complicated.It is proposed that particulatr attentions should be paid to the features in diagnosis and treatment for this type of injury and special efforts should be made for both life saving and limb salvage.

  19. Quality of Life of Nigerians with Unilateral Lower Limb Amputation

    Directory of Open Access Journals (Sweden)

    Christopher Olusanjo Akosile

    2013-02-01

    Full Text Available Purpose: The aims of this study were to determine the QoL of Nigerians with lower limb amputation and to investigate the influence of some clinical and socio-demographic variables on it. Method: Forty-seven individuals with lower limb amputation participated in this study. Participants’ age, gender, marital status, occupation, time since amputation, level of amputation, affected limb and use of prosthesis were recorded. Quality of life was then measured using the WHO QOL-BREF. Data were analysed using mean and standard deviation, Mann-Whitney U test and Kruskal-Wallis test at 0.05 alpha levels. Results: Participants’ overall health and QoL scores were 3.6(SD 0.9 and 3.9(SD 0.7 respectively. Male subjects had significantly higher scores than females in the domains of physical health (p = 0.007, social relationships (p = 0.024 and overall health (p = 0.012. Prosthesis-wearing subjects scored significantly higher in the domains of physical health (p = 0.015, psychological health (p = 0.008 and environment (p = 0.011 and overall health (0.033, than those not wearing prosthesis. Level of amputation, leg dominance and pre-amputation occupational category had no significant influence on participants’ QoL. Conclusion: The findings of this study suggest that the QoL of individuals with lower limb amputation in Nigeria is moderate. The only factors which have significant influence on some QoL domains are gender and use of prosthesis.Implications: Individuals with lower limb amputation, particularly females and those not wearing prosthesis, require special attention. Clinicians should identify barriers to the use of prosthesis so as to enhance their quality of life.

  20. The Ultimate Future of Artificial Life: Towards Artificial Cosmogenesis

    CERN Document Server

    Vidal, Clement

    2008-01-01

    This philosophical paper tries to tackle the question of what could be the ultimate future of ALife from a cosmic viewpoint. We first argue that the natural direction of ALife is a simulation of an entire universe. Two new challenges naturally arise. The first is to simulate open-ended evolution at all levels in a single simulation; i.e. not only in biology, but also to link it up a level below (physical evolution) and a level above (cultural evolution). The second challenge is to probe what would happen if we would "replay the tape of the universe". Assuming that intelligent life would indeed simulate an entire universe, this leads to two tentative hypotheses. Following the soft-ALife program, some authors argued that we could be in a simulation run by an intelligent entity. Following the hard/wet-ALife program, this would lead to an artificial cosmogenesis. This last direction is argued with a careful speculative philosophical approach, emphasizing the imperative to find a solution to the heat death problem...