Orthodistichous phyllotaxy and dorsiventral symmetry on adult shoots of Cyclanthus bipartitus (Cyclanthaceae, Monocotyledoneae)

1992 ◽  
Vol 70 (7) ◽  
pp. 1388-1400 ◽  
Author(s):  
George J. Wilder
Keyword(s):  
Growth Habit ◽  
Sagittal Plane ◽  
Convex Surface ◽  
Frontal Plane ◽  
Mirror Image ◽  
Concave Surface ◽  
Mature Leaves ◽  
Left Handed ◽  
Variable Species ◽  
New Type

An adult shoot of Cyclanthus bipartitus may simultaneously exhibit orthodistichy and dorsiventral symmetry, i.e., adult features previously unreported for Cyclanthus. As in previously investigated adult shoots of C. bipartitus with spirodistichous phyllotaxy, specimens presently described have sympodial rhizomes that form renewal shoots and terminal inflorescences. The phyllotaxy, symmetry, and sympodial structure of these specimens, collectively, represent a new type of growth habit in the Cyclanthaceae. On a shoot with orthodistichy the basal portions of mature leaves define a concave surface, convex surface, sagittal plane, and frontal plane. Plants grow upright on forest-covered slopes, and the concave surface and convex surface of a shoot are slope-opposed and slope-facing, respectively. Most emergent adventitious roots arise from the convex surface. Aspects of the form, symmetry, development, and orientation of a shoot are interpretable as adaptations to unequal illumination on its slope-facing versus slope-opposed sides. Presence of conspicuous dorsiventral symmetry is correlated with poorly expressed mirror-image symmetry, and shoots are neither left-handed nor right-handed, contrary to the condition in various Cyclanthaceae. Present findings bolster the conclusion that C. bipartitus is an extremely variable species. Key words: Cyclanthaceae, Cyclanthus, morphology, symmetry, phyllotaxy.

Normal and teratological pistillate spikes of Typha angustifolia (Typhaceae): gross aspects of morphology, anatomy, symmetry, and inflorescence dehiscence

1991 ◽  
Vol 69 (2) ◽  
pp. 321-335 ◽  
Author(s):  
George J. Wilder
Keyword(s):  
Sagittal Plane ◽  
Frontal Plane ◽  
Mirror Image ◽  
Typha Angustifolia ◽  
Consistent Manner ◽  
Central Stem ◽  
Length Width ◽  
The Individual

Normal and teratological pistillate spikes of Typha angustifolia were found at the same locality in Ohio, U.S.A., and the individual spikes exhibited radial, dorsiventral, and mirror-image symmetry, as well as polarity. Dorsiventral symmetry provided a frame of reference for comparing normal and teratological individuals. Both kinds of pistillate spikes were interpreted to have dorsal and ventral surfaces, sagittal and frontal planes, right and left sides, length, width, and height. Present in teratological spikes, but absent from normal ones, were either split(s) within the central stem axis or exceptionally long type-1 furrow(s). Split(s) or type-1 furrow(s) divided a teratological spike longitudinally into two to five subunits. Where two subunits were present, division was solely along the sagittal plane, whereas spikes with three to five subunits were divided along the sagittal plane and along, or parallel to, the frontal plane. In the case of teratological spikes with two to four subunits it was possible to number and compare subunits in a consistent manner. On some teratological spikes after splitting, subunits had become bowed, rotated, and curled or folded. Apparently, in teratological spikes, indentations and type-1 and type-2 furrows along the sagittal plane function, collectively, as a line of dehiscence. Key words: Typha, morphology, anatomy, symmetry, inflorescence, dehiscence.

Dependence of the joint configuration on the dynamic immobility fulcrum

2019 ◽  
pp. 108-114
Author(s):  
A. D. Kozlov ◽  
Yu. P. Potekhina
Keyword(s):  
Kinetic Energy ◽  
Convex Surface ◽  
The Other ◽  
Concave Surface ◽  
Joint Configuration ◽  
Articular Surfaces

Although joints with synovial cavities and articular surfaces are very variable, they all have one common peculiarity. In most cases, one of the articular surfaces is concave, whereas the other one is convex. During the formation of a joint, the epiphysis, which has less kinetic energy during the movements in the joint, forms a convex surface, whereas large kinetic energy forms the epiphysis with a concave surface. Basing on this concept, the analysis of the structure of the joints, allows to determine forces involved into their formation, and to identify the general patterns of the formation of the skeleton.

scholarly journals Using Biofeedback to Reduce Step Length Asymmetry Impairs Dynamic Balance in People Poststroke

2021 ◽  
pp. 154596832110193
Author(s):  
Sungwoo Park ◽  
Chang Liu ◽  
Natalia Sánchez ◽  
Julie K. Tilson ◽  
Sara J. Mulroy ◽  
...  
Keyword(s):  
Angular Momentum ◽  
Sagittal Plane ◽  
Dynamic Balance ◽  
Objective Measure ◽  
Frontal Plane ◽  
Step Length ◽  
Berg Balance Scale ◽  
Whole Body ◽  
Functional Gait ◽  
Full Body

Background People poststroke often walk with a spatiotemporally asymmetric gait, due in part to sensorimotor impairments in the paretic lower extremity. Although reducing asymmetry is a common objective of rehabilitation, the effects of improving symmetry on balance are yet to be determined. Objective We established the concurrent validity of whole-body angular momentum as a measure of balance, and we determined if reducing step length asymmetry would improve balance by decreasing whole-body angular momentum. Methods We performed clinical balance assessments and measured whole-body angular momentum during walking using a full-body marker set in a sample of 36 people with chronic stroke. We then used a biofeedback-based approach to modify step length asymmetry in a subset of 15 of these individuals who had marked asymmetry and we measured the resulting changes in whole-body angular momentum. Results When participants walked without biofeedback, whole-body angular momentum in the sagittal and frontal plane was negatively correlated with scores on the Berg Balance Scale and Functional Gait Assessment supporting the validity of whole-body angular momentum as an objective measure of dynamic balance. We also observed that when participants walked more symmetrically, their whole-body angular momentum in the sagittal plane increased rather than decreased. Conclusions Voluntary reductions of step length asymmetry in people poststroke resulted in reduced measures of dynamic balance. This is consistent with the idea that after stroke, individuals might have an implicit preference not to deviate from their natural asymmetry while walking because it could compromise their balance. Clinical Trials Number: NCT03916562.

scholarly journals DOES BRAIN ACTIVATION DURING FUNCTIONAL MOVEMENT TASKS DIFFERENTIATE BETWEEN GOOD AND BAD MOVERS? AN INTEGRATED NEUROIMAGING ASSESSMENT OF MOTOR CONTROL IN YOUNG ATHLETES

2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0013
Author(s):  
Manish Anand ◽  
Jed A. Diekfuss ◽  
Dustin R. Grooms ◽  
Alexis B. Slutsky-Ganesh ◽  
Scott Bonnette ◽  
...  
Keyword(s):  
Motor Control ◽  
Range Of Motion ◽  
Brain Function ◽  
Sagittal Plane ◽  
Brain Activity ◽  
Frontal Plane ◽  
Acl Injury ◽  
Timing Error ◽  
Lingual Gyrus ◽  
Increased Activity

Background: Aberrant frontal and sagittal plane knee motor control biomechanics contribute to increased anterior cruciate ligament (ACL) injury risk. Emergent data further indicates alterations in brain function may underlie ACL injury high risk biomechanics and primary injury. However, technical limitations have limited our ability to assess direct linkages between maladaptive biomechanics and brain function. Hypothesis/Purpose: (1) Increased frontal plane knee range of motion would associate with altered brain activity in regions important for sensorimotor control and (2) increased sagittal plane knee motor control timing error would associate with altered activity in sensorimotor control brain regions. Methods: Eighteen female high-school basketball and volleyball players (14.7 ± 1.4 years, 169.5 ± 7 cm, 65.8 ± 20.5 kg) underwent brain functional magnetic resonance imaging (fMRI) while performing a bilateral, combined hip, knee, and ankle flexion/extension movements against resistance (i.e., leg press) Figure 1(a). The participants completed this task to a reference beat of 1.2 Hz during four movement blocks of 30 seconds each interleaved in between 5 rest blocks of 30 seconds each. Concurrent frontal and sagittal plane range of motion (ROM) kinematics were measured using an MRI-compatible single camera motion capture system. Results: Increased frontal plane ROM was associated with increased brain activity in one cluster extending over the occipital fusiform gyrus and lingual gyrus ( p = .003, z > 3.1). Increased sagittal plane motor control timing error was associated with increased brain activity in multiple clusters extending over the occipital cortex (lingual gyrus), frontal cortex, and anterior cingulate cortex ( p < .001, z > 3.1); see Figure 1 (b). Conclusion: The associations of increased knee frontal plane ROM and sagittal plane timing error with increased activity in regions that integrate visuospatial information may be indicative of an increased propensity for knee injury biomechanics that are, in part, driven by reduced spatial awareness and an inability to adequately control knee abduction motion. Increased activation in these regions during movement tasks may underlie an impaired ability to control movements (i.e., less neural efficiency), leading to compromised knee positions during more complex sports scenarios. Increased activity in regions important for cognition/attention associating with motor control timing error further indicates a neurologically inefficient motor control strategy. [Figure: see text]

scholarly journals Biologically Inspired Design and Development of a Variable Stiffness Powered Ankle-Foot Prosthesis

2019 ◽  
Vol 11 (4) ◽  
Author(s):  
Alexander Agboola-Dobson ◽  
Guowu Wei ◽  
Lei Ren
Keyword(s):  
Lower Limb ◽  
Degrees Of Freedom ◽  
Sagittal Plane ◽  
Frontal Plane ◽  
Variable Stiffness ◽  
Plane Motion ◽  
Biologically Inspired ◽  
Passive Rotation ◽  
Ground Conditions ◽  
Biologically Inspired Design

Recent advancements in powered lower limb prostheses have appeased several difficulties faced by lower limb amputees by using a series-elastic actuator (SEA) to provide powered sagittal plane flexion. Unfortunately, these devices are currently unable to provide both powered sagittal plane flexion and two degrees of freedom (2-DOF) at the ankle, removing the ankle’s capacity to invert/evert, thus severely limiting terrain adaption capabilities and user comfort. The developed 2-DOF ankle system in this paper allows both powered flexion in the sagittal plane and passive rotation in the frontal plane; an SEA emulates the biomechanics of the gastrocnemius and Achilles tendon for flexion while a novel universal-joint system provides the 2-DOF. Several studies were undertaken to thoroughly characterize the capabilities of the device. Under both level- and sloped-ground conditions, ankle torque and kinematic data were obtained by using force-plates and a motion capture system. The device was found to be fully capable of providing powered sagittal plane motion and torque very close to that of a biological ankle while simultaneously being able to adapt to sloped terrain by undergoing frontal plane motion, thus providing 2-DOF at the ankle. These findings demonstrate that the device presented in this paper poses radical improvements to powered prosthetic ankle-foot device (PAFD) design.

scholarly journals Habitual Physical Activity as a Determinant of the Effect of Moderate Physical Exercise on Postural Control in Older Men

2012 ◽  
Vol 7 (1) ◽  
pp. 58-65 ◽  
Author(s):  
Rafał Stemplewski ◽  
Janusz Maciaszek ◽  
Maciej Tomczak ◽  
Robert Szeklicki ◽  
Dorota Sadowska ◽  
...  
Keyword(s):  
Physical Activity ◽  
Postural Control ◽  
Sagittal Plane ◽  
Center Of Pressure ◽  
Force Plate ◽  
Frontal Plane ◽  
Habitual Physical Activity ◽  
Similar Reaction ◽  
Mean Velocity ◽  
Ergometer Exercise

The aim of the study was to compare the effect of exercise on postural control (PC) among the elderly with lower or higher level of habitual physical activity (HPA). The study involved 17 elderly men (mean age 72.9 ± 4.79 years). Mean velocity of the center of pressure (COP) displacements was measured using a force plate both before and after cycle ergometer exercise. A significantly higher increase in mean velocity of COP displacements and its component in the sagittal plane were observed in the group with lower level of HPA in comparison with the group with higher HPA level. Simultaneously, a relatively similar reaction to the exercise in the frontal plane was observed in both groups, possibly connected to the specific type of used exercise, which mainly activated the sagittal muscles.

Correlation between craniovertebral angle in the sagittal plane and angles and indices measured in the frontal plane at the moment of inducing forward head posture

Work ◽  
2021 ◽  
pp. 1-7
Author(s):  
Samira Molaeifar ◽  
Farzaneh Yazdani ◽  
Amin Kordi Yoosefinejad ◽  
Mohammad Taghi Karimi
Keyword(s):  
Head And Neck ◽  
Negative Correlation ◽  
Sagittal Plane ◽  
Frontal Plane ◽  
Forward Head Posture ◽  
Head Posture ◽  
Digital Devices ◽  
Moderate Negative Correlation ◽  
The Moment ◽  
Craniovertebral Angle

BACKGROUND: Forward head posture (FHP) is the most common malposition in the head and neck area. With the growing use of digital devices, the prevalence of FHP may be expected to increase dramatically. Thus far, FHP has been evaluated only in the sagittal plane. OBJECTIVE: The objective of this study was to measure angles and indices from anatomical landmarks in the frontal plane and determine the possible correlations between these variables and craniovertebral angle (CVA) as an index of FHP in the sagittal plane. METHODS: Fifty eight healthy individuals (29 men, 29 women) between 18 and 40 years old participated in this cross-sectional study. Participants were evaluated with an 8-camera motion analysis system. After markers were placed on predetermined landmarks, the participants were asked to maintain their head and neck in the neutral position for 5 seconds. Then participants induced FHP by flexing and lowering their head. The correlation between CVA and a set of angles and indices was calculated at the moment of FHP induction. RESULTS: A moderate correlation was observed between 3-D CVA and the angle formed between the sternum and both tragi for the whole sample and separately in both sexes. A moderate negative correlation was observed between 3-D CVA and height, weight, and BMI in women. A moderate negative correlation was observed between 3-D CVA and height, weight, BMI, and hours on digital devices in men. CONCLUSIONS: Changes in CVA in the sagittal plane can be predicted from changes in the angle formed between the midpoint of the sternum and the left and right tragi in the frontal plane.

Microsurgically generated discontinuities provoke heritable changes in cellular handedness of a ciliate, Stylonychia mytilus

Development ◽  
1991 ◽  
Vol 111 (2) ◽  
pp. 337-356
Author(s):  
X.B. Shi ◽  
Z.I. Qiu ◽  
W. He ◽  
J. Frankel
Keyword(s):  
Large Scale ◽  
Mirror Image ◽  
The Other ◽  
Left Edge ◽  
Left Handed ◽  
Specific Manner ◽  
The Right ◽  
Anteroposterior Polarity ◽  
Posterior Anterior ◽  
Stylonychia Mytilus

Stylonychia mytilus is a dorsoventrally flattened ciliate with compound ciliary structures arranged in a specific manner on the cell surface. In mirror-image (MI) doublets of this ciliate, two nearly complete sets of ciliary structures are arrayed side-by-side, one in a normal or ‘right-handed’ (RH) arrangement, the other in a reversed or ‘left-handed’ (LH) arrangement. MI-doublets exist in two forms, one with the RH component on the right, the LH component on the left, and feeding structures near the center (‘buccal-adjoining MI-doublet’); the other with the RH component on the left, the LH component on the right, and feeding structures on the lateral edges (‘buccal-opposing MI-doublet’). We describe an operation that can generate either type of MI-doublet. This operation interchanges large anterior and posterior regions of the cell, transposing the original posterior region anteriorly (P—A) and the original anterior region posteriorly (A—P), while retaining the original anteroposterior polarity of each region. Two sets of new ciliary structures then are formed in mirror-image arrangement, with the set in the P—A region oriented normally and the set in the A—P region undergoing a reversal of polarity along its anteroposterior axis. This sometimes creates end-to-end MI forms, but more commonly produces side-by-side MI-doublets through a folding together of the P—A and A—P regions. This folding occurs because one lateral edge of the cell had been removed during the operation; if the left edge was removed, the complex folds to the left and forms a buccal-adjoining MI-doublet, whereas if the right edge was removed, the complex folds to the right and forms a buccal-opposing MI-doublet. Both types can reorganize and later divide true-to-type, although the ‘buccal-opposing’ type is by far the more stable of the two. The generation of mirror-image forms is dependent on the prior abnormal juxtaposition of regions from opposite ends of the cell, and involves a coordinated respecification of large-scale organization. We interpret this response to be a consequence of intercalation of missing intervening positional values in the zone of posterior-anterior abutment.

scholarly journals Static Range of Motion of the First Metatarsal in the Sagittal and Frontal Planes

2018 ◽  
Vol 7 (11) ◽  
pp. 456 ◽  
Author(s):  
Sandra Tavara-Vidalón ◽  
Manuel Monge-Vera ◽  
Guillermo Lafuente-Sotillos ◽  
Gabriel Domínguez-Maldonado ◽  
Pedro Munuera-Martínez
Keyword(s):  
Range Of Motion ◽  
Least Squares Method ◽  
Sagittal Plane ◽  
Frontal Plane ◽  
Neutral Position ◽  
Future Design ◽  
First Metatarsal ◽  
Medial Cuneiform ◽  
First Ray ◽  
Degree Equation

The first metatarsal and medial cuneiform form an important functional unit in the foot, called “first ray”. The first ray normal range of motion (ROM) is difficult to quantify due to the number of joints that are involved. Several methods have previously been proposed. Controversy exists related to normal movement of the first ray frontal plane accompanying that in the sagittal plane. The objective of this study was to investigate the ROM of the first ray in the sagittal and frontal planes in normal feet. Anterior-posterior radiographs were done of the feet of 40 healthy participants with the first ray in a neutral position, maximally dorsiflexed and maximally plantarflexed. They were digitalized and the distance between the tibial malleolus and the intersesamoid crest in the three positions mentioned was measured. The rotation of the first ray in these three positions was measured. A polynomic function that fits a curve describing the movement observed in the first ray was obtained using the least squares method. ROM of the first ray in the sagittal plane was 6.47 (SD 2.59) mm of dorsiflexion and 6.12 (SD 2.55) mm of plantarflexion. ROM in the frontal plane was 2.69 (SD 4.03) degrees of inversion during the dorsiflexion and 2.97 (SD 2.72) degrees during the plantarflexion. A second-degree equation was obtained, which represents the movement of the first ray. Passive dorsiflexion and plantarflexion of the first ray were accompanied by movements in the frontal plane: 0.45 degrees of movement were produced in the frontal plane for each millimeter of displacement in the sagittal plane. These findings might be useful for the future design of instruments for clinically quantifying first ray mobility.

scholarly journals 3D kinematic analysis of patients’ gait before and after unilateral total hip replacement

2020 ◽  
Vol 22 (2) ◽  
Author(s):  
Kateřina Kolářová ◽  
Tomáš Vodička ◽  
Michal Bozděch ◽  
Martin Repko
Keyword(s):  
Range Of Motion ◽  
Total Hip Replacement ◽  
Kinematic Analysis ◽  
Hip Replacement ◽  
Sagittal Plane ◽  
Frontal Plane ◽  
Step Length ◽  
Total Hip ◽  
Before And After ◽  
Analysis System

Purpose: The purpose of the study was to describe changes in the kinematic parameters in the patients’ gait after total hip replacement. Methods: Research group of men in the end stage of osteoarthritis indicated to the THR (n = 10; age 54.1 ± 7.5 years; weight 92.2 ± 9.6 kg; height 179.7 ± 5.9 cm). All participants underwent a total of three measurements: before surgery, 3 and 6 months after the surgery. Using the 3D kinematic analysis system, the patients’ gait was recorded during each measurement session and kinematic analysis was carried out. The parameters that were monitored included the sagittal range of motion while walking in the ankle, the knee and the hip joints of the operated and the unoperated limb, and the range in the hip joint’s frontal plane, the rotation of pelvis in the frontal and transverse planes, as well as the speed of walking and the walking step length. Results: Significant increases were found in sagittal range of motion in the operated hip joint, sagittal range of motion in the ankle joint on the unoperated side and in the walking step length of the unoperated limb. Conclusions: During walking after a THR, the sagittal range of motion in the ankle of the unoperated limb increases. Also, the range of motion in the sagittal plane on the operated joint increases, which is related to the lengthening of the step of the unoperated lower limb.

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