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Posture
Kinds of Posture Selected AbstractsOn functional motor adaptations: from the quantification of motor strategies to the prevention of musculoskeletal disorders in the neck,shoulder regionACTA PHYSIOLOGICA, Issue 2010P. Madeleine Abstract Background:, Occupations characterized by a static low load and by repetitive actions show a high prevalence of work-related musculoskeletal disorders (WMSD) in the neck,shoulder region. Moreover, muscle fatigue and discomfort are reported to play a relevant initiating role in WMSD. Aims: To investigate relationships between altered sensory information, i.e. localized muscle fatigue, discomfort and pain and their associations to changes in motor control patterns. Materials & Methods:, In total 101 subjects participated. Questionnaires, subjective assessments of perceived exertion and pain intensity as well as surface electromyography (SEMG), mechanomyography (MMG), force and kinematics recordings were performed. Results:, Multi-channel SEMG and MMG revealed that the degree of heterogeneity of the trapezius muscle activation increased with fatigue. Further, the spatial organization of trapezius muscle activity changed in a dynamic manner during sustained contraction with acute experimental pain. A graduation of the motor changes in relation to the pain stage (acute, subchronic and chronic) and work experience were also found. The duration of the work task was shorter in presence of acute and chronic pain. Acute pain resulted in decreased activity of the painful muscle while in subchronic and chronic pain, a more static muscle activation was found. Posture and movement changed in the presence of neck,shoulder pain. Larger and smaller sizes of arm and trunk movement variability were respectively found in acute pain and subchronic/chronic pain. The size and structure of kinematics variability decreased also in the region of discomfort. Motor variability was higher in workers with high experience. Moreover, the pattern of activation of the upper trapezius muscle changed when receiving SEMG/MMG biofeedback during computer work. Discussion:, SEMG and MMG changes underlie functional mechanisms for the maintenance of force during fatiguing contraction and acute pain that may lead to the widespread pain seen in WMSD. A lack of harmonious muscle recruitment/derecruitment may play a role in pain transition. Motor behavior changed in shoulder pain conditions underlining that motor variability may play a role in the WMSD development as corroborated by the changes in kinematics variability seen with discomfort. This prognostic hypothesis was further, supported by the increased motor variability among workers with high experience. Conclusion:, Quantitative assessments of the functional motor adaptations can be a way to benchmark the pain status and help to indentify signs indicating WMSD development. Motor variability is an important characteristic in ergonomic situations. Future studies will investigate the potential benefit of inducing motor variability in occupational settings. [source] Effects of immersion water temperature on whole-body fluid distribution in humansACTA PHYSIOLOGICA, Issue 1 2004J. M. Stocks Abstract Aim:, In this study, we quantified acute changes in the intracellular and extracellular fluid compartments during upright neutral- and cold-water immersion. We hypothesized that, during short-term cold immersion, fluid shifts would be wholly restricted to the extracellular space. Methods:, Seven males were immersed 30 days apart: control (33.3 ° SD 0.6 °C); and cold (18.1 ° SD 0.3 °C). Posture was controlled for 4 h prior to a 60-min seated immersion. Results:, Significant reductions in terminal oesophageal (36.9 ° ± 0.1 °,36.3 ° ± 0.1 °C) and mean skin temperatures (30.3 ° ± 0.3 °,23.0 ° ± 0.3 °C) were observed during the cold, but not the control immersion. Both immersions elicited a reduction in intracellular fluid [20.17 ± 6.02 mL kg,1 (control) vs. 22.72 ± 9.90 mL kg,1], while total body water (TBW) remained stable. However, significant plasma volume (PV) divergence was apparent between the trials at 60 min [12.5 ± 1.0% (control) vs. 6.1 ± 3.1%; P < 0.05], along with a significant haemodilution in the control state (P < 0.05). Plasma atrial natriuretic peptide concentration increased from 18.0 ± 1.6 to 58.7 ± 15.1 ng L,1 (P < 0.05) during cold immersion, consistent with its role in PV regulation. We observed that, regardless of the direction of the PV change, both upright immersions elicited reductions in intracellular fluid. Conclusion:, These observations have two implications. First, one cannot assume that PV changes reflect those of the entire extracellular compartment. Second, since immersion also increases interstitial fluid pressure, fluid leaving the interstitium must have been rapidly replaced by intracellular water. [source] Myofascial Trigger Points, Neck Mobility, and Forward Head Posture in Episodic Tension-Type HeadacheHEADACHE, Issue 5 2007César Fernández-de-las-Peñas PT Objective.,To assess the differences in the presence of trigger points (TrPs) in head and neck muscles, forward head posture (FHP) and neck mobility between episodic tension-type headache (ETTH) subjects and healthy controls. In addition, we assess the relationship between these muscle TrPs, FHP, neck mobility, and several clinical variables concerning the intensity and the temporal profile of headache. Background.,TTH is a headache in which musculoskeletal disorders of the craniocervical region might play an important role in its pathogenesis. Design.,A blinded, controlled pilot study. Methods.,Fifteen ETTH subjects and 15 matched controls without headache were studied. TrPs in both upper trapezius, both sternocleidomastoids, and both temporalis muscles were identified according to Simons and Gerwin diagnostic criteria (tenderness in a hypersensible spot within a palpable taut band, local twitch response elicited by snapping palpation, and elicited referred pain with palpation). Side-view pictures of each subject were taken in both sitting and standing positions, in order to assess FHP by measuring the craniovertebral angle. A cervical goniometer was employed to measure neck mobility. All measures were taken by a blinded assessor. A headache diary was kept for 4 weeks in order to assess headache intensity, frequency, and duration. Results.,The mean number of TrPs for each ETTH subject was 3.7 (SD: 1.3), of which 1.9 (SD: 0.9) were active, and 1.8 (SD: 0.9) were latent. Control subjects only had latent TrPs (mean: 1.5; SD: 1). TrP occurrence between the 2 groups was significantly different for active TrPs (P < .001), but not for latent TrPs (P > .05). Differences in the distribution of TrPs were significant for the right upper trapezius muscles (P= .04), the left sternocleidomastoid (P= .03), and both temporalis muscles (P < .001). Within the ETTH group, headache intensity, frequency, and duration outcomes did not differ depending on TrP activity, whether the TrP was active or latent. The craniovertebral angle was smaller, ie, there was a greater FHP, in ETTH patients than in healthy controls for both sitting and standing positions (P < .05). ETTH subjects with active TrPs in the analyzed muscles had a greater FHP than those with latent TrPs in both sitting and standing positions, though differences were only significant for certain muscles. Finally, ETTH patients also showed lesser neck mobility than healthy controls in the total range of motion as well as in half-cycles (except for cervical extension), although neck mobility did not seem to influence headache parameters. Conclusions.,Active TrPs in the upper trapezius, sternocleidomastoid, and temporalis muscles were more common in ETTH subjects than in healthy controls, although TrP activity was not related to any clinical variable concerning the intensity and the temporal profile of headache. ETTH patients showed greater FHP and lesser neck mobility than healthy controls, although both disorders were not correlated with headache parameters. [source] Trigger Points in the Suboccipital Muscles and Forward Head Posture in Tension-Type HeadacheHEADACHE, Issue 3 2006César Fernández-de-las-Peñas PT Objective.,To assess the presence of trigger points (TrPs) in the suboccipital muscles and forward head posture (FHP) in subjects with chronic tension-type headache (CTTH) and in healthy subjects, and to evaluate the relationship of TrPs and FHP with headache intensity, duration, and frequency. Background.,Tension-type headache (TTH) is a prototypical headache in which myofascial TrPs in the cervical and pericranial musculature can play an important role. Design.,A blinded, controlled pilot study. Methods.,Twenty CTTH subjects and 20 matched controls without headache participated. TrPs were identified by eliciting referred pain with palpation, and increased referred pain with muscle contraction. Side-view pictures of each subject were taken in sitting and standing positions, in order to assess FHP by measuring the craniovertebral angle. Both measures were taken by a blinded assessor. A headache diary was kept for 4 weeks in order to assess headache intensity, frequency, and duration. Results.,Sixty-five percent (13/20) CTTH subjects showed active TrPs and 35% (7/20) had latent TrPs in the suboccipital muscles. Six (30%) controls also had latent TrPs. Differences in the presence of suboccipital muscle TrPs between both the groups were significant for active TrPs (P < .001) but not for latent TrPs (P > .5). CTTH subjects with active TrPs reported a greater headache intensity and frequency than those with latent TrPs (P < .05). The degree of FHP was greater in CTTH subjects than in controls in both sitting and standing positions (P < .01). Within the CTTH group, there was a negative correlation between the craniovertebral angle and the frequency of headache (rs=,0.6, P < .01, in sitting position; rs=,0.5, P < .05, in standing position). CTTH subjects with active TrPs had a greater FHP than those with latent TrPs, though this difference was not significant. Conclusions.,Suboccipital active TrPs and FHP were associated with CTTH. CCTH subjects with active TrPs reported a greater headache intensity and frequency than those with latent TrPs. The degree of FHP correlated positively with headache duration, headache frequency, and the presence of suboccipital active TrPs. [source] Posture, muscular tone and visual attention in 5 month-old infantsINFANT AND CHILD DEVELOPMENT, Issue 4 2002Carole Lefèvre Abstract The present paper aims at studying the relationships between posture, muscle tone and visual attention in 5 month-old infants. To this end, a specially designed seating arrangement made it possible to vary posture while keeping constant the spatial relationship between eyes and stimuli. Five month-olds were placed in the reclining position (30°) or in a more erect position (60°). The more erect the posture, the more difficult it should be for the infant to maintain a straight body axis. Muscle tone was evaluated, and infants distinguished in terms of whether they were hypertonic or hypotonic. It was hypothesised that in a more erect position hypotonic children, who experience more difficulties in maintaining posture, should organise their visual exploration in ways different from those considered to be hypertonic. To test it, pairs of three-dimensional stimuli were presented in the distal visual field for one group (N=48) and in the proximal visual field in another group (N=32) for 2 min in each posture. The dynamical organisation of attention was evaluated through the number and duration of fixations on each target, the number of shifts from one target to the other (alternations) and the number of repetitions (back to the previous target). Results showed that visual behaviour was significantly affected by the distance at which stimuli were presented. Infants spent more time in visual exploration when the object was within reach than when it was out of reach. Although posture was shown to play a role in the organisation of visual exploration, no link with muscle tone was found, a surprising result which is discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source] Clinical Characteristics of Flexed Posture in Elderly WomenJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 10 2003Lara Balzini PT Objectives: To investigate the relationships between the severity of flexed posture (FP), skeletal fragility, and functional status level in elderly women. Design: Cross-sectional study. Setting: Geriatric rehabilitation research hospital. Participants: Sixty elderly women (aged 70,93) with FP referred to a geriatric rehabilitation department for chronic back pain without apparent comorbid conditions. Measurements: Multidimensional clinical assessment included the severity of FP (standing occiput-to-wall distance) demographic (age) and anthropometric (height, weight) data, clinical profile (number of falls, pain assessment, Mini-Mental State Examination, Comorbidity Severity Index, Geriatric Depression Scale, Multidimensional Fatigue Inventory), measures of skeletal fragility (number of vertebral fractures by spine radiograph, bone mineral density (BMD), and T-score of lumbar spine and proximal femur), muscular impairment assessment (muscle strength and length), motor performance (Short Physical Performance Battery, Performance Oriented Mobility Assessment, instrumented gait analysis), and evaluation of disability (Barthel Index, Nottingham Extended Activities of Daily Living Index). Results: The severity of FP was classified as mild in 11, moderate in 28, and severe in 21 patients. Although there were no differences between FP groups on the skeletal fragility measurements, the moderate and severe FP groups were significantly different from the mild FP group for greater pain at the level of the cervical and lumbar spine. The severe FP group was also significantly different from the mild but not the moderate FP group in the following categories: clinical profile (greater depression, reduced motivation), muscle impairment (weaker spine extensor, ankle plantarflexor, and dorsiflexor muscles; shorter pectoralis and hip flexor muscles), the motor function performance-based tests (lower scores in the balance and gait subsets of the Performance Oriented Mobility Assessment), the instrumented gait analysis (slower and wider base of support), and disability (lower score on the Nottingham Extended Activities of Daily Living Index). The total number of vertebral fractures was not associated with differences in severity of FP, demographic and anthropometric characteristics, clinical profile, muscular function, performance-based and instrumental measures of motor function, and disability, but it was associated with reduced proximal femur and lumbar spine BMD. Conclusion: The severity of FP in elderly female patients (without apparent comorbid conditions) is related to the severity of vertebral pain, emotional status, muscular impairments, and motor function but not to osteoporosis, and FP has a measurable effect on disability. In contrast, the presence of vertebral fractures in patients with FP is associated with lower BMD but not patients' clinical and functional status. Therefore, FP, back pain, and mobility problems can occur without osteoporosis. Older women with FP and vertebral pain may be candidates for rehabilitation interventions that address muscular impairments, posture, and behavior modification. Randomized controlled trials are needed to support these conclusions. [source] Hyperkyphotic Posture and Risk of Future Osteoporotic Fractures: The Rancho Bernardo Study,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2006Mei-Hua Huang Abstract It is unknown whether kyphosis of the thoracic spine is an independent risk factor for future osteoporotic fractures. In 596 community-dwelling women, we found that with increasing kyphosis, there was a significant trend of increasing fracture risk that was independent of previous history of fractures or BMD. Introduction: It is unknown whether kyphosis of the thoracic spine is an independent risk factor for future osteoporotic fractures. Materials and Methods: We conducted a prospective cohort study of 596 community-dwelling women, 47-92 years of age. Between 1988 and 1991, BMD of the hip and spine and kyphosis were measured. Kyphosis was measured by counting the number of 1.7-cm blocks necessary to place under the occiput so participants could lie flat without neck hyperextension. New fractures were reported over an average follow-up of 4 years. Results: Using a cut-off of at least one block, 18% of the participants had hyperkyphotic posture (range, one to nine blocks). There were 107 women who reported at least one new fracture (hip, spine, wrist, clavicle, shoulder, arm, hand, rib, pelvis, leg, or ankle). In logistic regression analyses, older women with hyperkyphotic posture (defined as at least one block) had a 1.7-fold increased risk of having a future fracture independent of age, prior fracture, and spine or hip BMD (95% CI: 1.00-2.97; p = 0.049). There was a significant trend of increasing fracture risk with increasing number of blocks, with ORs ranging from 1.5 to 2.6 as the number of blocks increased from one to at least three blocks compared with those with zero blocks (trend p = 0.03; models adjusted for age, baseline fracture, spine or hip BMD). Stratification by baseline fracture status and controlling for other possible confounders or past year falls did not change the results. Conclusions: Whereas hyperkyphosis may often result from vertebral fractures, our study findings suggest that hyperkyphotic posture itself may be an important risk factor for future fractures, independent of low BMD or fracture history. [source] Choreography of Characters: Movement and Posture in Illustrated Texts for ChildrenLITERACY, Issue 3 2001Sirke Happonen This paper begins with the premise that very often, in analysing or just talking about illustrated books, one uses the word ,movement', or ,motion', to express the characteristics of a picture or a series of them. In the research literature, remarks on movement link with the dynamics of a story, depicting action, alternating situations, and the liveliness and diversity of the book as a whole. In regard to both pictures and texts, however, the concept of movement remains rather abstract and vague; we mostly talk about an illusion, whose origin is difficult to express precisely. This article discusses the concept of movement first in the broader sense and then seeks an alternative viewpoint on analysing movement in illustrated children's literature. It particularly emphasises movement in relation to the characters, inspired by ideas from modern dance. Examples are drawn from the illustrations and texts of the Moomin books by Finnish artist and author Tove Jansson. [source] Mal de Debarquement and Posture: Reduced Reliance on Vestibular and Visual CuesTHE LARYNGOSCOPE, Issue 3 2004Zohar Nachum MD Abstract Objective The neural mismatch theory assumes that the intersensory conflicts leading to motion sickness are resolved by changes in the relative weighting of the various senses that contribute to orientation. If this sensory rearrangement persists after disembarkment, it might result in mal de debarquement (MD): ataxia and a rocking sensation sometimes felt after landing. The objective of the present study was to examine possible changes in sensory organization in naval crew members with differing susceptibility to MD with computerized dynamic posturography (CDP). Study Design Cross-sectional parallel-group design. Methods Seventeen subjects susceptible to MD (SMD) and 17 subjects nonsusceptible to MD (NSMD) (healthy male volunteers aged 18,22) participated in the study. CDP was performed twice with each subject, before and immediately after sailing, using the EquiTest system (NeuroCom, Inc., Clackamas, OR). Results The SMD group showed a significant reduction in their scores on sensory organization tests 3, 4, and 5 after sailing. Sensory pattern analysis revealed reduced use of inputs from the vestibular and visual systems to maintain balance. Prolonged latencies of the motor responses to unexpected pitch perturbations were also recorded in the postsailing CDP of the SMD group. Reduced performance on the presailing CDP task, which presents the greatest challenge to the vestibular system, was found to control for the presence of MD postsailing. Conclusions The results show that MD is associated with postural instability, slower motor reflexes, and larger sways in response to abrupt changes in the body's center of gravity. These findings may be explained by under reliance on vestibular and visual inputs and increased dependence on the somatosensory system for the maintenance of balance. [source] Posture and ventilator associated pneumoniaANAESTHESIA, Issue 4 2000R. Self No abstract is available for this article. [source] Body size and joint posture in primatesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009John D. Polk Abstract Body mass has been shown in experimental and comparative morphological studies to have a significant effect on joint posture in major limb joints. The generalizability of experimental studies is limited by their use of small sample sizes and limited size ranges. In contrast, while comparative morphological studies often have increased sample sizes, the connection between joint posture and morphological variables is often indirect. The current study infers joint postures for a large sample of primates using an experimentally validated method, and tests whether larger primates use more extended joint postures than smaller species. Postures are inferred through the analysis of patterns of subchondral bone apparent density on the medial femoral condyle. Femora from 94 adult wild-shot individuals of 28 species were included. Apparent density measurements were obtained from CT scans using AMIRA software, and the angular position of the anterior-most extent of the region of maximum apparent density on the medial femoral condyle was recorded. In general, the hypothesis that larger-bodied primates use more extended knee posture was supported, but it should be noted that considerable variation exists, particularly at small body sizes. This indicates that smaller species are less constrained by their body size, and their patterns of apparent density are consistent with a wide range of knee postures. The size-related increase in inferred joint posture was observed in most major groups of primates, and this observation attests to the generalizability of Biewener's model that relates body size and joint posture. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] A moving planar mirror based approach for cultural reconstructionCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2004Kyung Ho Jang Abstract Modelling from images is a cost-effective means of obtaining virtual cultural heritage models. These models can be effectively constructed from classical Structure from Motion algorithm. However, it's too difficult to reconstruct whole scenes using SFM method since general oriental historic sites contain a very complex shapes and brilliant colours. To overcome this difficulty, the current paper proposes a new reconstruction method based on a moving planar mirror. We devise the mirror posture instead of scene itself as a cue for reconstructing the geometry. That implies that the geometric cues are inserted into the scene by compulsion. With this method, we can obtain the geometrical details regardless of the scene complexity. For this purpose, we first capture image sequences through the moving mirror containing the interested scene, and then calibrate the camera through the mirror's posture. Since the calibration results are still inaccurate due to the detection error, the camera pose is revised using frame-correspondence of the corner points that are easily obtained using the initial camera posture. Finally, 3D information is computed from a set of calibrated image sequences. We validate our approach with a set of experiments on some cultural heritage objects. Copyright © 2004 John Wiley & Sons, Ltd. [source] Stakeholder engagement and corporate social responsibility reporting: the ownership structure effectCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 2 2009Jose-Manuel Prado-Lorenzo Abstract Social disclosure, according to Ullmann's conceptual framework (1985), could be explained by stakeholder power, strategic posture and economic performance, where the power of stakeholders is a function of the resources they control that are essential to the company. The aim of this work is to test the effect that shareholder power and dispersed ownership structure have on the decision to disclose corporate social responsibility (CSR) information in the Spanish context, controlling for the rest of the dimensions. Our results allow us to affirm that this paper tests a stakeholder theory approach to analyzing corporate social disclosures and is consistent with the framework proposed, although the power of shareholders is quite limited. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment. [source] Correlation of dystrophin,glycoprotein complex and focal adhesion complex with myosin heavy chain isoforms in rat skeletal muscleACTA PHYSIOLOGICA, Issue 4 2009S. Masuda Abstract Aim:, The dystrophin,glycoprotein complex (DGC) and focal adhesion complex (FAC) are transmembrane structures in muscle fibres that link the intracellular cytoskeleton to the extracellular matrix. DGC and FAC proteins are abundant in slow-type muscles, indicating the structural reinforcement which play a pivotal role in continuous force output to maintain posture for long periods. The aim of the present study was to examine the expression of these structures across fast-type muscles containing different myosin heavy chain (MHC) isoform patterns which reflect the fatigue-resistant characteristics of skeletal muscle. Methods:, We measured the expression of dystrophin and ,1 integrin (representative proteins of DGC and FAC respectively) in plantaris, extensor digitorum longus, tibialis anterior, red and white portions of gastrocnemius, superficial portion of vastus lateralis and diaphragm, in comparison with soleus (SOL) and cardiac muscle from rats. Results:, The expression of dystrophin and ,1 integrin correlated positively with the percentage of type I, IIa and IIx MHC isoforms and negatively with that of type IIb MHC isoform in fast-type skeletal muscles, and their expression was abundant in SOL and cardiac muscle. Conclusion:, Our results support the idea that DGC and FAC are among the factors that explain the fatigue-resistant property not only of slow-type but also of fast-type skeletal muscles. [source] Education, Values, and Valuing in Cosmopolitan PerspectiveCURRICULUM INQUIRY, Issue 5 2009DAVID T. HANSEN ABSTRACT In this article we describe a cosmopolitan orientation toward the place of values in human life. We argue that a cosmopolitan outlook can assist people in engaging the challenges of being thrown together with others whose roots, traditions, and inheritances differ. We show that cosmopolitanism implies neither an elite nor an aloof posture toward human affairs. On the contrary, the concept illuminates how people everywhere can retain individual and cultural integrity while also keeping themselves open to the larger world. A cosmopolitan outlook positions people to consider not just the specific values they subscribe to, but also their ways of holding and enacting them. This move provides people valuable distance from values although not a break with them. It helps people consider the value of valuing as well as the value of reflecting upon values. We examine three arts, or artful methods, that can fuel this orientation. They are hope, memory, and dialogue: three familiar concepts that we accent in a distinctive way in light of the idea of cosmopolitanism. We show how these arts can be cultivated continuously through education. [source] In vivo determination of muscle viscoelasticity in the human legACTA PHYSIOLOGICA, Issue 4 2001S. Fukashiro The purpose of this study was to examine the methodological validity of the free vibration technique for determining individual viscoelastic characteristics of the human triceps surae muscle-tendon complex (MTC) in vivo. Six subjects sat with first phalangeal joint of the forefoot on the edge of a force-plate. The special frame on the knee was loaded with weight (0,40 kg) for testing. Oscillations of the triceps surae MTC system were initiated with a hand-held hammer by tapping the weight. In order to keep the same posture, the output of the force plate was displayed on the oscilloscope and subjects were asked to maintain the beam on the oscilloscope at a particular location in relation to a reference line. The damped oscillations in conjunction with the equation of motion of a damped mass-spring model were used to calculate the viscosity of muscle (b) and the elasticity of muscle fibres and tendon (k) in each subject, considering moment arm of the ankle joint. With this arrangement, we have obtained high reproducibility in this method. The coefficient of variations (CVs) of b and k in five trials at each weight were quite small (range: 0.5,18.7% in b and 1.0,15.1% in k). There were no significant differences in viscoelastic coefficients between right and left legs. Therefore, it appears that free vibration technique, used here, is adequate in describing the viscoelastic characteristics of the triceps surae in vivo in humans. [source] Ergonomics in Office-Based Surgery: A Survey-Guided Observational StudyDERMATOLOGIC SURGERY, Issue 11 2007ADAM C. ESSER MD BACKGROUND The practice of office-based surgery is increasing in many specialties. OBJECTIVE Using Mohs surgery as a model, we investigated the role of ergonomics in office-based surgery to limit work-related musculoskeletal disorders. METHODS All Mayo Clinic surgeons currently performing Mohs surgery and Mohs surgeons trained at Mayo Clinic between 1990 and 2004 received a questionnaire survey between May 2003 and September 2004. A sample of respondents were videotaped during surgery. The main outcome measures were survey responses and an ergonomist's identification of potential causes of musculoskeletal disorders. RESULTS All 17 surgeons surveyed responded. Those surveyed spend a mean of 24 hours per week in surgery. Sixteen said they had symptoms caused by or made worse by performing surgery. Symptom onset occurred on average at age 35.4 years. The most common complaints were pain and stiffness in the neck, shoulders, and lower back and headaches. Videotapes of 6 surgeons revealed problems with operating room setup, awkward posture, forceful exertion, poor positioning, lighting, and duration of procedures. CONCLUSION Symptoms of musculoskeletal injuries are common and may begin early in a physician's career. Modifying footwear, flooring, table height, operating position, lighting, and surgical instruments may improve the ergonomics of office-based surgery. [source] Early motor repertoire is related to level of self-mobility in children with cerebral palsy at school ageDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2009JANNEKE LM BRUGGINK MD Aim, To determine the predictive value of the early motor repertoire for the level of self-mobility in children with cerebral palsy (CP) at school age. Method, Video recordings were made at 11 to 17 weeks post-term of 37 preterm infants (20 males, 17 females) who later developed CP. The early motor repertoire was assessed by obtaining a motor optimality score. At 6 to 12 years, children were classified according to the Gross Motor Function Classification System (GMFCS). Results, Of 37 children (mean gestational age 29.1wks, SD 1.9; mean birthweight 1273g, SD 324), nine had unilateral and 28 had bilateral spastic CP. Twelve children were in GMFCS level I, three level II, 10 level III, four level IV, and eight level V. The absence of the age-adequate motor repertoire, a cramped motor repertoire, an abnormal kicking pattern, and a non-flat supine posture were associated with lower levels of self-mobility (,2 for trend test, p<0.05). Predictive for a low level of self-mobility was a cramped motor repertoire/non-flat supine posture (positive predictive values [PPV] 100%, negative predictive values [NPV] 54%). Predictive for a high level of self-mobility was a non-cramped repertoire/flat supine posture (PPV 80%, NPV 74%). Interpretation, Several aspects of the motor repertoire at 11 to 17 weeks post-term predicted the degree of functional limitations in children with CP at school age. [source] Maternal care affects the development of maternal behavior in inbred miceDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2009Hirotaka Shoji Abstract The present study investigated the effects of variations in maternal behavior on the development of maternal behavior of female offspring in BALB/c and CBA/Ca inbred mice. In Experiment 1, we conducted fostering within or between the two strains and observed the maternal behaviors of mothers and female offspring for 2 weeks postpartum. Although fostering changed the maternal behavior of mothers in both strains, CBA mothers generally showed greater frequency of nursing posture and pup licking than BALB mothers. BALB female offspring reared by CBA mothers showed more body licking than those reared by BALB mothers, whereas fostering did not affect the maternal behavior of CBA female offspring. In Experiment 2, we examined the maternal behavior of females of F1 hybrids derived from reciprocal crosses between the two strains to confirm the maternal effect demonstrated in Experiment 1. Female F1 hybrids from CBA mothers showed more arched-back nursing, body licking, and nest building than those from BALB mothers. These results suggested that maternal care affect the development of maternal behavior in inbred mice, though the contributions of genetic and prenatal factors cannot be ignored. © 2009 Wiley Periodicals, Inc. Dev. Psychobiol 51: 345,357, 2009. [source] Development of somatosensory-motor integration: An event-related analysis of infant posture in the first year of independent walkingDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2005J. S. Metcalfe Abstract The ability to integrate sensation with action is considered an important factor underlying the development of upright stance and locomotion. While many have studied sensory influences on posture, the nature of these influences and how they change with development have yet to be thoroughly characterized in infancy. Six infants were examined from 1 month prior to walk onset until 9 months of independent walking experience while standing quietly and touching either a static or a dynamic surface. Five adults were examined performing an analogous task. An event-related, time-frequency analysis was used to assess the relationship between postural sway and the motion of the somatosensory stimulus. Phase consistency between sway and stimulus was observed for both adults and infants, and with walking experience the infants increased their phase consistency rather than changing aspects of response amplitude. It is concluded that walking experience provides opportunities for an active tuning of sensorimotor relations for adequate estimation of body position in space and thus facilitates refined control over temporal aspects of postural sway. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 46: 19,35, 2005. [source] Motor processes in children's imagery: the case of mental rotation of handsDEVELOPMENTAL SCIENCE, Issue 5 2005Marion Funk In a mental rotation task, children 5 and 6 years of age and adults had to decide as quickly as possible if a photograph of a hand showed a left or a right limb. The visually presented hands were left and right hands in palm or in back view, presented in four different angles of rotation. Participants had to give their responses with their own hands either in a regular, palms-down posture or in an inverted, palms-up posture. For both children and adults, variation of the posture of their own hand had a significant effect. Reaction times were longer the more awkward it was to bring their own hand into the position shown in the stimulus photograph. These results, together with other converging evidence, strongly suggest that young children's kinetic imagery is guided by motor processes, even more so than adults'. [source] The Effect of Hemodialysis on Left Ventricular Outflow Tract GradientECHOCARDIOGRAPHY, Issue 6 2010Pawel Petkow Dimitrow M.D. Background: The aim of the study was to assess the effect of hemodialysis (HD) on left ventricular outflow tract gradient (LVOTG) measured both in supine and upright position (provocative maneuver to unload LV cavity by rapid preload reduction). Supine/standing echocardiography was performed immediately before and immediately after HD. For additional verification of the hypothesis about preload-dependence of LVOTG, the echocardiograms after long (2-day delay HD due to weekend) versus short (usual 1-day) pause between HDs were compared. Methods: Forty-one patients on chronic HD (mean age 44 ± 11 years) were examined using a portable hand-carried echocardiograph. In accordance with the prestudy assumption the ultrafiltration volume was significantly greater during HD after a long pause in comparison to HD after a short pause (3707 ± 2826 mL vs. 2665 ± 1152 mL P < 0.05). Results: After a long pause, the mean value of LVOTG at the pre-HD was mildly increased in the supine position and remained at a similar level in the upright position (13.1 ± 6.1 vs. 13.6 ± 9.1 mmHg). Mean LVOTG at the post-HD in the supine position was similar to pre-HD, however the orthostatic stress test induced a significant increase of LVOTG (13.9 ± 15.2 vs. 18.2 ± 19.9 mmHg P < 0.05). After a short pause at the pre-HD the LVOTG in the supine position and after the orthostatic provocation was very similar to measurements after long pause (13.3 ± 9.1 vs. 13.3 ± 10.8 mmHg). At the post-HD the mean value of LVOTG increased during upright posture but the differences were of borderline significance (13.2 ± 6.6 vs. 17.9 ± 18.6 mmHg P = 0.052). Conclusions: HD predisposed to standing-provoked LVOTG especially when a long pause (2 days) between HDs induced a greater weight gain and subsequently a larger volume of ultrafiltration was needed to reduce hypervolemia. (Echocardiography 2010;27:603-607) [source] AIChE offers technological insights to the public policy debate on global climate changeENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 3 2000David E. Gushee Global climate change has been a major issue on the national political agenda since 1988. Several Committees on Capitol Hill conducted hearings concerning the heat waves then searing the nation. Testimony by several well-regarded scientists at those hearings that "we ain't seen nothing yet" led to impressive headlines in the national media. Since then, unusually high temperatures, a succession of forecasts of serious negative impacts from the projected continued warming, and well-publicized Congressional hearings led to the creation of the United Nation's Framework Convention on Climate Change (FCCC) and its Kyoto Protocol. As a result, climate change is on just about every technology organization's agenda. In 1996, the American Institute of Chemical Engineers joined the list of organizations formally responding to the issue. The Government Relations Committee (GRC) formed a Task Force on Climate Change, made up of Institute members active in a number of aspects of the issue area. The charge to the Task Force: Look for opportunities for the Institute to contribute to the public policy debate on the issue and frame position papers accordingly. The first major conclusion of the Task Force was that AIChE is not in a position to state whether or not global climate change is a real public policy problem. However, to the extent that the public policy process treats climate change as an issue, the Institute is well positioned to comment on the technical merits of proposed policy responses. The Task Force recommended this posture to the GRC, which agreed. [source] Conspecifics and Their Posture Influence Site Choice and Oviposition in the Damselfly Argia moestaETHOLOGY, Issue 8 2009Catherine J. Byers Finding a suitable oviposition site can be costly because of energy and time requirements, and ovipositioning can be dangerous because of the risk of predation and harassment by males. The damselfly Argia moesta oviposits, contact-guarded by her mate, on vegetation in streams. Oviposition aggregations are commonly observed in this species, despite their territorial nature during other behaviors. We conducted experiments in the field to test the hypothesis that aggregations are the result of conspecific attraction. In the first experiment, two oviposition sites (sycamore leaves) were provided, one with models of ovipositing pairs, and one without. In the second experiment, one leaf again had ovipositing models, while the other had models of uncoupled males and females in a resting posture. In both experiments, damselfly pairs preferred the site with ovipositing models. In general, they visited the ovipositing models first more often than expected by chance, stayed longer there, were more likely to oviposit there, and laid a greater total number of eggs there. These results support the hypothesis that conspecific attraction is responsible for ovipositing aggregations in A. moesta and that posture is an important cue for attraction. Using conspecific cues could be a beneficial strategy to save in search costs while taking advantage of the presence of ovipositing conspecifics to dilute the effects of harassment and predation. [source] Allonursing in Captive Guanacos, Lama guanicoe: Milk Theft or Misdirected Parental Care?ETHOLOGY, Issue 8 2009Beatriz Zapata Females in several ungulates transfer milk to non-filial (NF) offspring, in a process known as allonursing. This behavior is less common in monotocous species, including most ungulates, and it has been associated with parasitic behavior of calves or mothers who have lost their own offspring. To examine whether the calves ,steal' milk from the females or whether females fail to discriminate their own calves in guanacos, allonursing behavior was observed. If milk theft drives allonursing, mothers should reject NF offspring, they should search for their own calves, and calves attempting to suckle from alien mothers should adopt parallel (as opposed to the anti-parallel) position during allonursing. Alternatively, if allonursing is caused by mothers unable to discriminate own offspring, mothers are not expected to reject NF offspring, and alien calves should use parallel and antiparallel position similarly when allonursing. Allonursing was investigated during the first 3 mo of lactation in two groups of captive guanacos composed of 15 and 14 mother-calf pairs, respectively. While 40% and 62.5% of mothers in groups 1 and 2 performed allonursing, high individual variation prevailed; some females exhibited this behavior infrequently (4.1% and 6.5 % in groups 1 and 2). The rejection rate to NF nursing attempts was threefold higher than the rejection rate to filial nursing attempts. The occurrence of nursing to NF was associated to a parallel posture by the calves. Our findings suggest that ,milk theft' is a more plausible hypothesis to explain allonursing in guanacos than ,misdirected parental care'. [source] Scent-Marking of Giant Otter in the Southern Pantanal, BrazilETHOLOGY, Issue 3 2009Caroline Leuchtenberger Giant otters live in social groups, consisting of a mating pair and one or two litters. Groups are territorial and mark their territories often with scent-marks. Our objectives were to evaluate the frequencies of marking and over-marking according to the social status of the individuals and to define the different postures used during the marking. We observed four groups, totaling 25 individuals (five alpha males, four alpha females, seven adult females, one adult male and eight juveniles) with group size ranging between four and 13 individuals. The study was conducted between July 2006 and July 2007 in the Vermelho River and in a stretch of the Miranda River, in the Southern Pantanal. We observed the groups for a total of 2006 min and recorded 95 events of marking totaling 84.9 min. Time spent marking varied between groups and ranged from 4.3 to 44.7 min. The alpha males marked more frequently (62% of marking events, 55 min) than the alpha females (17% of marking events, 13.6 min). Of the 59 events of scent-marking by the alpha males, 32 over-marked the marks of other individuals from the group. Of the 16 events of scent-marking of the alpha females, five over-marked that of other females from the same group. When scent-marking, alpha males used the ,stepping' posture most frequently (63%), then ,fore-paw rubbing' (24%), ,latrine use' (7%), and ,body rubbing' (6%). Alpha females used the ,stepping' posture most frequently (65%), then ,latrine use' (19%) and ,fore-paw rubbing' (12%), with only one event of ,body rubbing' observed during marking. Subordinate females used the ,stepping' posture (76%) and ,latrine use' (24%) during marking. Scent-marking can play many roles in mammals and for giant otters, and the main roles appear to be communication of social and sexual status and territorial defense. [source] Extended Mother,Offspring Relationships in Crayfish: The Return Behaviour of Juvenile Procambarus ClarkiiETHOLOGY, Issue 10 2008Laura Aquiloni Crayfish shows a relatively complex parental behaviour compared with other invertebrates, but the literature provides only anecdotal accounts of this phenomenon. In Procambarus clarkii, we described the ,return' behaviour of third-stage juveniles when offered four types of adults: biological mothers, foster mothers, non-brooding females and males. Then, we analysed the posture and behaviour of the adults to understand the role played by the putative mother in attracting the juveniles. Contrary to non-brooding individuals, both biological and foster mothers displayed a relatively rare locomotion, executed few cleaning and feeding acts, and never attempted to prey on juveniles. They often assumed a ,spoon-like telson posture' that seemed to facilitate offspring's approaches. Juveniles increased the frequency of tail-flips away in the presence of non-brooding adults; conversely, they accepted foster mothers, along with biological mothers, but not as fast as the latter. Taken together, these results suggest that mother,offspring relationships in P. clarkii are more refined than previously thought, being possibly a key factor enabling this species to thrive in harsh environmental conditions. [source] Does Lateral Presentation of the Palmate Antlers During Fights by Fallow Deer (Dama dama L.) Signify Dominance or Submission?ETHOLOGY, Issue 5 2002Dómhnall J. Jennings A central aim of the study of animal communication is to identify the mode and content of information transferred between individuals. The lateral presentation of the antler palm between male fallow deer has been described as either a signal of individual quality or an attempt to avoid fighting. In the first case two phenotypic features have been proposed by which transmission of individual quality may be facilitated. These are antler size and antler symmetry. The alternative hypothesis proposes that the lateral presentation of antlers occurs as a consequence of averting a threatening posture and may signify a reluctance to fight. We examined whether mature fallow deer use lateral palm presentation as a display during fights to indicate antler size and symmetry. We found no relationship between presentation rate of the antler and antler size and symmetry. Furthermore, males did not preferentially present their larger antler to their opponent. We also investigated whether the rate at which males presented antlers laterally during a fight was related to their ability to win the fight. Our results show that the male who performed more presentations during a fight was more likely to lose it. There were behavioural differences in the way in which a bout of presentation ended; subsequent losers tended to turn their body away from their opponent and subsequent winners tended to lower their antlers to an opponent which we interpret as an invitation to continue fighting. We conclude that the lateral palm presentation serves to de-escalate fighting between mature fallow deer. It is not a mechanism by which to communicate individual quality but rather an indication that a male is less committed to continuing investment in the current contest. [source] Temperature Effects on Anti-Predator Behaviour in Rhabdophis tigrinus, a Snake with Toxic Nuchal GlandsETHOLOGY, Issue 9 2001Akira Mori Many contextual factors affect the anti-predator behaviour of animals. In ectotherms, in which most physiological activities depend on body temperature, ambient temperature is one of the most important of these factors. We examined the effects of temperature on the anti-predator behaviour of an ectotherm, the Japanese grass snake (Rhabdophis tigrinus). This species has a large repertoire of anti-predator behavioural responses. Among these responses are several anti-predator displays that appear to be unique to this species and perhaps others in a small group of closely related species possessing nuchal glands containing toxic secretions that may be derived from their toxic toad diet. Snakes were tested at room temperatures of 14, 22 and 30°C with order of temperatures balanced. A long wand modified to simulate initial contact by a predator was used as the stimulus. Snakes exhibited rather passive responses (neck flatten, body flatten, neck arch and immobile) more frequently at low temperatures, and fled more frequently at high temperatures. The dorsal facing posture, a characteristic posture directed against the stimulus, was observed more frequently at low temperatures. Threatening, assertive responses such as strike were rarely observed. These results showed that R. tigrinus shifts its anti-predator behaviour from multiple passive responses to active flight responses with increasing temperature. This snake species thus appears to rely more on its nuchal glands as a predator deterrent at low ambient temperatures. Consistent individual variation was also observed, and its adaptive and causal bases are discussed. [source] Signals and Signal Choices made by the Araneophagic Jumping Spider Portia fimbriata while Hunting the Orb-Weaving Web spiders Zygiella x-notata and Zosis geniculatusETHOLOGY, Issue 7 2000Michael Tarsitano Portia fimbriata is a web-invading araneophagic jumping spider (Salticidae). The use of signal-generating behaviours is characteristic of how P. fimbriata captures its prey, with three basic categories of signal-generating behaviours being prevalent when the prey spider is in an orb web. The predatory behaviour of P. fimbriata has been referred to as aggressive mimicry, but no previous studies have provided details concerning the characteristics of P. fimbriata's signals. We attempt to determine the model signals for P. fimbriata's ,aggressive mimicry' signals. Using laser Doppler vibrometer and the orb webs of Zygiella x-notata and Zosis geniculatus, P. fimbriata's signals are compared with signals from other sources. Each of P. fimbriata's three categories of behaviour makes a signal that resembles one of three signals from other sources: prey of the web spider (insects) ensnared in the capture zone of the web, prey making faint contact with the periphery of the web and large-scale disturbance of the web (jarring the spider's cage). Experimental evidence from testing P. fimbriata with two sizes of lure made from Zosis (dead, mounted in a lifelike posture in standard-size orb web) clarifies P. fimbriata's signal-use strategy: (1) when the resident spider is small, begin by simulating signals from an insect ensnared in the capture zone (attempt to lure in the resident spider); (2) when the resident spider is large, start by simulating signals from an insect brushing against the periphery of the web (keep the resident spider out in the web, but avoid provoking from it a full-scale predatory attack); (3) when walking in the resident spider's web, regardless of the resident spider's size, step toward the spider while making a signal that simulates a large-scale disturbance of the web (mask footsteps with a self-made vibratory smokescreen). [source] | |||||||||||||||||||||||||||||||||||||||||||