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PubMed1982

[A new approach for evaluation of the rotational deformity in scoliosis. Part I: The development of an apparatus measuring truncal cross-sections and quantitative rotational indices of scoliosis].

It is indispensable in the diagnosis and treatment of idiopathic scoliosis to estimate the axial rotation deformity as well as the lateral flexion deformity. Because of lack of methodology till now, appropriate quantitative estimation of the former deformity has not been available for the routine clinical use. The purpose of this investigation was to propose a new approach which makes it possible to evaluate the rotational deformity of scoliosis more precisely than ever. To realize an idea that a two-dimentional morphologic measurement through horizontal planes is reasonable for the recognition of the rotational deformity, a new experimental apparatus named Laser Torsograph was constructed for the purpose of measuring horizontal cross-sections of the human body surface. The fundamentals of the measuring system is an optical triangulation using a laser spot which is detected by a line sensor camera. While the laser spot is turned around the trunk horizontally for 360 degrees, input data of the positions of the laser spot on the trunk surface are compiled into a minicomputer and processed to be visualized as cross-sectional figures on a display and X-Y plotter. Each cross-sections thus measured are computerized for the quantitative assessment of the deformity and three parameters (theta, phi, psi) are obtained full-automatically. Theta represents the degree of the spatial rotation of the cross-section (the position change). Phi represents the degree of the distorsion of the cross-section itself (the shape change). Psi represents the difference of thickness between the right and left half of the cross-section. By measuring cross-sections at multi-levels of each spinous processes for a scoliotic patient, the rotational indices of scoliosis are determined as the maximum values of each parameters. As a result of application of Laser Torsography to 109 cases of idiopathic scoliosis, the usefulness of this method has been established. The rotational deformity was obvious on inspection of cross-sections and convincing informations about structural changes were offered which were helpful, for example, to define the curve patterns objectively. Our innovative approach will provide the routine clinical situations with the precise visualization and appropriate quantitative data on the axial rotational deformity in scoliosis.

Adolescent↗
PubMed1999

Vibration-Internal Rotation-Overall Rotation Interactions in CH(2)DOH and CHD(2)OH.

The zeroth-order kinetic energy is developed for the vibrating-rotating-internally rotating CH(2)DOH and CHD(2)OH molecules using the general theory of Guan and Quade for the vibration-rotation-large amplitude internal motion interactions in molecules. A T transformation is applied to obtain the necessary (G(-1))(0) vibrational matrix elements in the kinetic energy for the R transformation that separates the internal rotation from the 3N-7 other vibrations. Then, a second T transformation is used to separate rotation from the 3N-7 other vibrations in zeroth order in the kinetic energy. The overall rotation and internal rotation remain coupled in zeroth order. All zeroth-order kinetic energy coefficients are calculated from the molecular structure and masses for the methyl alcohol molecules. The physical significance of the transformations is discussed in detail. This paper reports the results of the first segment of the three segments that are necessary in the calculation of the full solution to the problem. Copyright 1999 Academic Press.

Journal Article↗
PubMed1990

Rotational relaxation rate of 1,6-diphenyl-1,3,5-hexatriene in cytoplasmic membranes of Bacillus subtilis. A new model of heterogeneous rotations.

The temperature dependence of fluorescence anisotropy, lifetime and differential tangent of 1,6-diphenyl-1,3,5-hexatriene (DPH) and its polar trimethylammonium derivative (TMA-DPH) were investigated in cytoplasmic membranes of Bacillus subtilis. The fluorescence parameters were compared in the two types of membranes prepared from bacteria cultivated at 20 and 40 degrees C. Steady-state anisotropy measurements showed that within a broad range of temperatures, membranes cultivated at 20 degrees C exhibit significantly lower values than those prepared from cells cultivated at 40 degrees C. The temperature dependence of lifetime and differential tangent measurements (differential polarized phase fluorimetry) were fully consistent with steady-state anisotropy data of both DPH and TMA-DPH. The low anisotropy values in the case of TMA-DPH could be explained by a shorter lifetime and higher temperature-induced decrease as compared with DPH. Surprisingly, the temperature dependence of rotational rate R calculated according to the model of hindered rotations (Lakowicz 1983) gave misleading results. When increasing the temperature from 5 to 25 degrees C, a marked drop of rotational relaxation rate was observed. The minimum R values were measured between 25 and 30 degrees C and further increase of temperature (up to 60 degrees C) was reflected as increase of the R values. Therefore, a new model of "heterogeneous rotations" was developed. This model assumes that even at low temperatures (approaching 0 degrees C) where the differential tangent reaches zero, a fraction of fast rotating molecules exists. The ratio between fast and slowly rotating molecules may be expressed by this model, the newly calculated rotational rates are fully consistent with anisotropy, lifetime and differential tangent measurements and represent the monotonically increasing function of temperature.

Bacillus subtilis↗
PubMed2001

Pre-registration house officer rotations incorporating general practice: does the order of rotation matter?

CONTEXT: In relation to pre-registration house officer (PRHO) rotations incorporating general practice, previous research has recommended that where possible, no PRHO should undertake general practice as the first placement, because of the difficulties encountered. It was recognized that logistically, this could make such schemes almost unworkable. Within the context of a larger qualitative evaluation comparing how 24 PRHOs learned in hospital and general practice settings, the issue of rotation order was explored. METHODS: In-depth semistructured interviews were conducted with the 12 PRHOs who were involved in general practice rotations. They were interviewed at the beginning and end of the PRHO year, and following their return to hospital work after the general practice placement. RESULTS: Each rotation order had both advantages and disadvantages, with no particular rotation order being obviously better or worse for the PRHOs involved. CONCLUSIONS: This small qualitative evaluation has highlighted a number of advantages and disadvantages specific to each rotation order, and makes some practical recommendations to help alleviate the problems encountered. It is important that future evaluations of similar schemes consider this issue, as there are conflicting reports about the significance of the rotation order.

Attitude of Health Personnel↗
PubMed2005

Calculation of the tau dependence of the vibration-internal rotation-overall rotation interactions in CH3OH from molecular structure and molecular dynamics.

The Guan and Quade theory for vibration-large-amplitude internal-motion-rotation interactions has been applied to the internal rotation problem in CH(3)OH. Through the molecular dynamics, the cos 3tau and sin 3tau dependence of the torsional-rotational coefficients in the effective Hamiltonian have been calculated from molecular structure. The internal rotation coordinate tau(') for the vibrationally distorted molecule is shown to have the necessary threefold symmetry for all values of tau('). For the methyl deformation modes, the vibrational dependence of the internal rotation potential energy is shown to have a threefold symmetry. The S(t) and S(t)S(t) dependence of the inertia tensor and Coriolis coupling coefficients has been developed in terms of curvilinear internal coordinates. The T transformation separating rotation from vibrations in zeroth order is then applied, the kinetic-energy tensor inverted to momentum space, and finally the effective torsion-rotation coefficients are calculated by Van Vleck perturbation theory. When compared to the empirical results, the kinetic-energy contributions to the cos 3tau and sin 3tau dependence of the coefficients are as follows: 54% of P(a)(2) is accounted for, 28% of P(a)P(b), 16% of P(a)P(c), and 91% of the asymmetry. The calculation is inadequate to account for the P(b)(2),P(c)(2), and P(b)P(c) coefficients, ranging from factors of 20-70, even with the incorrect sign for some of the terms. Anharmonic force contributions from the vibrations have not been used in the calculation since these forces are not known at this time.

Journal Article↗
PubMed1983

The lateral coding of rotations: a study of the simon effect with wheel-rotation responses.

A number of experimental studies have consistently shown the locus of spatial S-R compatibility effects to be the selection of the response within an abstract memory code. The purpose of the present study was to test, in the particular case of wheel rotations, the general proposition that any response that a subject internally codes in terms of left and right may be interfered with by the lateral location of the stimuli in a Simon paradigm. Experiment 1 showed that the auditory Simon effect occurred in a task where the subjects had to rotate a steering wheel bimanually either clockwise or counterclockwise according to sound pitch, despite the fact that responses of this kind are undefined with respect to laterality. Experiment 2 confirmed this result in a unimanual rotation condition and suggested that the ear-rotation compatibility effect may be added to the effect of a biomechanical factor, pronation versus supination, supporting the idea of an abstraction motor code. In Experiment 3, subjects rotated the steering wheel with their hands on the lowest part of the wheel. When the response movement made the spot of a C.R.T. move laterally in accordance with the performed rotation, the subjects coded their response directly in terms of its effect on the visual display. For subjects not receiving visual feedback, no compatibility effect occurred. however, the individual data were compatible with the notion that some subjects in this group coded their responses in terms of wheel rotations, and others in terms of hand movements.

Journal Article↗
PubMed2006

Rotation-invariant texture image retrieval using rotated complex wavelet filters.

This paper proposes a novel approach for rotation-invariant texture image retrieval by using set of dual-tree rotated complex wavelet filter (DT-RCWF) and DT complex wavelet transform (DT-CWT) jointly, which obtains texture features in 12 different directions. Two-dimensional RCWFs are nonseparable and oriented, which improves characterization of oriented textures. Robust and efficient isotropic rotationally invariant features are extracted from DT-RCWF and DT-CWT decomposed subbands. This paper demonstrates the effectiveness of this new set of features on four different sets of rotated and nonrotated databases. Experimental results indicate that the proposed method improves retrieval accuracy from 83.17% to 93.71% on a small size (208 images) nonrotated database D1, from 82.71% to 90.86% on a small size (208 images) rotated database D2, from 72.18% to 76.09% on a medium-size (640 images) rotated database D3, and from 64.17% to 78.93% on a large size (1856 images) rotated database D4, compared with the discrete wavelet transform-based approach. New method also retains comparable levels of computational complexity.

Journal Article↗
PubMed1985

Effects of a psychiatric rotation on psychiatric knowledge and attitudes towards psychiatry in rotating interns.

The attitudes of trainees toward Psychiatry affect their career choice and ability to properly identify and manage emotional disorders in their patients. These attitudes are determined by several factors which include preclinical and clinical training among others. We report here a study of the attitude of interns toward psychiatry using the 30 item attitude toward psychiatry (ATP-30) scale. The ATP-30 and a multiple choice questionnaire examination (MCQE) in psychiatry were completed by 96 interns at the beginning and end of their compulsory four week psychiatry rotation. The degree of satisfaction of the trainees was rated in four areas--orientation, teaching/learning experience, overall rating of rotation and relevance of rotation to career choice. There was no significant change in the mean ATP-30 scores (N = 55) during the four week rotation, but the MCQE scores (N = 74) improved significantly (P less than 0.0001). A repeated analysis of variance for the four satisfaction variables by change score in MCQE and change score in ATP-30 did not show any significant main effects or significant interactions between these change scores except with relevance of rotation. Reasons for the absence of changes in the ATP-30 scores during this rotation were explored. The implications of the improved knowledge during this rotation are also discussed. We also conclude that attitudinal change and knowledge are two independent factors which should be assessed independently in trainees.

Adult↗
PubMed1997

Femoral anteversion related to side differences in hip rotation. Passive rotation in 1,140 children aged 8-9 years.

We assessed whether the range of passive hip motion is reliable for predicting abnormal femoral anteversion. We measured the passive medial and lateral rotation in extension in both hips of 1,140 children between 8 and 9 years of age. The children were divided into 3 groups: group 1: difference between lateral and medial rotation less than 10 degrees; group 2: medial rotation more than 10 degrees greater than the lateral; group 3: lateral rotation more than 10 degrees greater than the medial. Group 1 comprised 90% of the children, whereas 8% belonged to group 2 and 2% to group 3. The angle of femoral neck anteversion was measured in 57 children from the first group, in 67 from the second and in 24 children from the third group, using biplane radiography. The mean anteversion angles in the 3 groups were 24 degrees, 36 degrees and 14 degrees, respectively. To predict an abnormally high anteversion angle (above mean +2SD), the difference between medial and lateral rotation must be 45 degrees or more, whereas an abnormally low anteversion angle (lower than mean -2SD) could be predicted when the lateral rotation was at least 50 degrees higher than the medial rotation.

Child↗
PubMedDate not supplied

Prospective evaluation of the effect of rotator cuff integrity on the outcome of open rotator cuff repairs.

BACKGROUND: Open rotator cuff repairs have led to excellent clinical results; however, several studies have linked postoperative structural integrity to patient outcomes. The purpose of this study is to prospectively assess postoperative cuff integrity after open rotator cuff repair and assess its relationship to clinical outcome. HYPOTHESIS: Preoperative rotator cuff tear size and postoperative rotator cuff integrity are important factors in overall clinical outcomes. STUDY DESIGN: Prospective nonrandomized clinical outcomes study. METHODS: Forty-seven consecutive patients undergoing repair of full-thickness rotator cuff tears by a single surgeon were enrolled in this prospective study. A standardized evaluation was performed preoperatively and postoperatively at annual intervals. All patients underwent postoperative magnetic resonance imaging at least 1 year after surgery. Statistical evaluation was performed using paired and unpaired 2-tailed t tests for comparison. RESULTS: Thirty-two patients were available for evaluation. Overall, the patients experienced a significant (P < .05) improvement in their American Shoulder and Elbow Surgeons survey (40-85) and Constant (53-80) scores. The overall retear rate was 31%. Although patients with large tears preoperatively and retears postoperatively had lower overall outcomes scores, this was not significant. CONCLUSION: These data support open rotator cuff repair as an effective technique that restores excellent shoulder function. The authors did not find postoperative cuff integrity to have a significant effect on outcomes when compared with those with an intact cuff. In fact, those with a retear still had a significant improvement in all clinical areas assessed, including strength.

Adult↗
PubMed2005

Timing of rotator cuff activation during shoulder external rotation in throwers with and without symptoms of pain.

STUDY DESIGN: Fine-wire EMG rotator cuff onset time analysis in 2 matched groups of throwers with and without pain. OBJECTIVE: To identify if there is a difference in the activation patterns of the rotator cuff muscles during a rapid shoulder external rotation task between throwers with and without pain. BACKGROUND: The coordinated action of the rotator cuff is recognized as essential for glenohumeral joint control in the throwing athlete. Identification of abnormalities occurring in muscle activation patterns for injured athletes is relevant when prescribing rehabilitative exercises. METHODS AND MEASURES: Twelve throwers with shoulder pain were compared to a matched group of 11 asymptomatic throwers. Participants were matched for age, height, body mass, and habitual activity. Fine-wire EMG electrodes were inserted into the subscapularis, supraspinatus, and infraspinatus. EMG activity was measured during a reaction time task of rapid shoulder external rotation in a seated position. The timing of onset of EMG activity was analyzed in relation to visualization of a light (reaction time) and to the onset of infraspinatus activity (relative latency). RESULTS: In the group with shoulder pain, the onset of subscapularis activity was found to be significantly delayed (reaction time, P = .0018; relative latency, P = .0005) from the onset of infraspinatus activity when compared to the control group. CONCLUSIONS: The presence of shoulder pain in these athletes was associated with a difference in the onset of subscapularis EMG activity during a rapid shoulder external rotation movement. This was an initial step in the understanding of the joint protection mechanisms of the glenohumeral joint and the problems that occur in throwers. This information may assist in providing future guidelines for more effective rehabilitation and prevention strategies for this condition.

Adult↗
PubMed2001

Changing the direction of flagellar rotation in bacteria by modulating the ratio between the rotational states of the switch protein FliM.

One of the major questions in bacterial chemotaxis is how the switch, which controls the direction of flagellar rotation, functions. It is well established that binding of the signaling molecule CheY to the switch protein FliM shifts the rotation from the default direction, counterclockwise, to clockwise. How this shift is done is still a mystery. Our aim in this study was to determine the correlation between the fraction of FliM molecules in the clockwise state (i.e. occupied by CheY) and the probability of clockwise rotation. For this purpose we gradually expressed, from a plasmid, a clockwise FliM mutant protein in cells that express, from the chromosome, wild-type FliM but no chemotaxis proteins. We verified that plasmid-borne FliM exchanges chromosomal FliM in the switch. Surprisingly, a substantial clockwise probability was not obtained before the large majority of the FliM molecules in the switch were clockwise molecules. Thereafter, the rise in clockwise probability was very steep. These results suggest that an increase in the clockwise probability requires a high level of FliM occupancy by CheY approximately P. They further suggest that the steep increase in clockwise rotation upon increasing CheY levels, reported in several studies, is due, at least in part, to cooperativity of post-binding interactions within the switch. We also carried out the inverse experiment, in which wild-type FliM was gradually expressed in a background of a clockwise fliM mutant. In this case, the level of the clockwise mutant protein, required for establishing a certain clockwise probability, was lower than in the original experiment. If our system (in which the ratio between the rotational states of FliM in the switch is established by slow exchange) and the native system (in which the ratio is established by fast changes in FliM occupancy) are comparable, the results suggest that hysteresis is involved in the switch function. Such a situation might reflect a damping mechanism, which prevents a situation in which fluctuations in the phosphorylation level of CheY throw the switch from one direction of rotation to the other.

Bacterial Proteins↗
PubMed1987

Response characteristics of neurons in the cat vestibular nuclei during slow and constant velocity off-vertical axes rotations in the clockwise and counterclockwise rotations.

The responses to slow constant velocity rotations in the clockwise (CW) and counterclockwise (CCW) directions about an axis tilted 10 degrees from the earth's vertical were studied in static tilt-sensitive neurons in the vestibular nuclei of decerebrate cats. Each unit responded to any 360 degrees unidirectional rotation with a position-dependent discharge maximum. The location of the maximum, obtained by rotation in one direction, differed from that obtained by an oppositely directed rotation (phase difference). In about 80% of the units such phase difference (up to 160 degrees in second-order neurons) in response to oppositely directed rotations was unaffected by different amplitudes of head displacement (5-25 degrees). Units were thus classified into two groups depending on the location of the CW discharge maximum relative to the CCW counterpart. The direction of rotation had no influence on the response gains of these units.

Animals↗
PubMed2006

The effect of necrotic lesion size and rotational degree on the stress reduction in transtrochanteric rotational osteotomy for femoral head osteonecrosis--a three-dimensional finite-element simulation.

BACKGROUND: The prospect for success in the efficacy of osteotomy for precollapse stage of femoral head osteonecrosis depends on the ability to predict reliably the stress changes derived from specific osteotomies. A three-dimensional finite-element analysis was thus designed to compute necrotic femoral head stress changes with different extent of necrocrosis that accompany anterior or posterior rotational osteotomies. METHOD: Computed tomography images of a standard composite femur were used to create the three-dimensional finite-element intact femur model. Based on the intact model, 27 models simulating three different levels of necrotic region together with nine different rotational osteotomies were created. The von Mises stress distributions of each model were analyzed and compared for a loading condition simulating single-legged stance. FINDINGS: (1) The stress reduction in anterior rotational osteotomy is more effective as compared to that of the posterior rotational osteotomy for various necrotic lesion sizes. (2) Von Mises stress on the necrotic zone decreased with increasing rotational angle. The decreasing rate was higher for the femoral head with a narrow lesion. (3) Femoral head with a wider necrotic lesion had a higher risk for developing collapse due to high local stress on the surface of necrotic region; whereas the necrotic region tended to expand in size instead of collapse for femoral head with a narrow lesion due to high local stress on the interface between necrotic region and healthy bone. INTERPRETATION: Transtrochanteric rotational osteotomy is a technically demanding procedure and associated with high complication risks, a more scrupulous planning including the finite-element analysis should be considered before doing surgery in clinical subjects.

Femur Head↗
PubMed2004

Anticipatory postural adjustments associated with rotational perturbations while standing on fixed and free-rotating supports.

OBJECTIVE: The role of anticipatory postural adjustments (APAs) has been commonly hypothesized to stabilize the body's center of mass (COM) from reaction forces and torques induced by voluntary movements in a feed-forward manner. This hypothesis was developed from studies which investigated movements that induced anterior-posterior or medial-lateral perturbation to body posture. However, the role of APAs in tasks that induce perturbations about the vertical axis, which are associated with minimal COM displacements, is unclear. The purpose of this study was to examine APAs associated with upper arm movements that induce perturbation about the body's vertical axis. METHODS: Eight healthy subjects performed bilateral or unilateral shoulder movements in the sagittal or frontal plane that induced rotational perturbation about the body's vertical axis, while standing on a support which was either fixed or free to rotate about the body's vertical axis. Changes in the background activity of trunk and leg muscles on both sides of the body, as well as reaction moment about the vertical axis were quantified within the time interval typical of APAs. RESULTS: On the fixed support, clear asymmetry between right and left muscle activity was observed in biceps femoris and soleus during APAs across all tasks. These asymmetries were specific to the movement direction. When the same tasks were performed on a free-rotating support, the asymmetry that was observed on fixed support decreased. CONCLUSIONS: We suggest that the CNS uses asymmetric activity of right and left muscles during APAs to rotate the body segments in the direction opposite to the perturbation. When ground reaction moments did not aid in counteracting the forthcoming perturbation while standing on a free-rotating support, the asymmetric muscle activity decreased to minimize further inter-segmental rotations.

Adult↗
PubMedDate not supplied

Sensitivity to full-field visual movement compatible with head rotation: variations among axes of rotation.

Movement detection thresholds for full-field visual motion about various axes were measured in three subjects using a two-alternative forced-choice staircase method. Thresholds for 1-s exposures to rotation about different rotation axes varied significantly over the range 0.139 +/- 0.05 deg/s to 0.463 +/- 0.166 deg/s. The highest thresholds were found in response to rotation about axes closely aligned to the line of sight. Variations among the thresholds for different axes could not be explained by different movement patterns in the fovea or variations in motion sensitivity with eccentricity. The variations can be well simulated by a three-channel model for coding the axis and velocity of full-field visual motion. A three-channel visual coding system would be well suited for extracting information about self-rotation from a complex pattern of retinal image motion containing components due to both rotation and translation. A three-channel visual motion system would also be readily compatible with vestibular information concerning self-rotation arising from the semicircular canals.

Adult↗
PubMed2003

Transient kinetics and mechanics of myosin's force-generating rotation in muscle: resolution of millisecond rotational transitions in the spin-labeled myosin light-chain domain.

We have used electron paramagnetic resonance (EPR) of spin-labeled scallop muscle, in conjunction with laser flash photolysis of caged ATP, to resolve millisecond rotational transitions of the myosin light-chain domain (LCD) during transient force generation. We previously used EPR to resolve two distinct orientations of the LCD [Baker, J. E., Brust-Mascher, I., Ramachandran, S., LaConte, L. E., and Thomas, D. D. (1998) Proc. Natl. Acad. Sci. U.S.A. 95, 2944-2949], correlated these structural states with biochemical states in the actin-myosin ATPase reaction, and showed that a small shift in the steady-state distribution between these two LCD orientations (i.e., a net lever arm rotation) is associated with force generation in muscle. In the study presented here, we measured millisecond changes in this orientational distribution (i.e., the rates of transition between the two LCD orientations) in muscle following flash photolysis of caged ATP, in both the presence and absence of Ca. The transient acquired in the absence of Ca is dominated by a rapid (1/tau(1) = 37 s(-1)) disordering transition from the single orientation in rigor to the bimodal orientation distribution observed for detached cross-bridges in relaxation (i.e., the reversal of the lever arm rotation), followed by a recovery phase (1/tau(2) = 2.4 s(-1)) of very small amplitude (small fraction of heads participating). In the presence of Ca, the transient exhibited a similar initial disordering phase (1/tau(1) = 38.5 s(-1)), followed by a recovery phase (1/tau(2) = 8.33 s(-1)) of substantial amplitude, corresponding to the forward rotation and ordering of the lever arm. A standard kinetic model was used to fit these data, revealing rate constants consistent with those previously determined by other methods. Surprisingly, a comparison of the EPR transients with force transients reveals that the rate of force development (91 s(-1)) is faster than the rate of the forward lever arm rotation (8 s(-1)). This observed relationship between the kinetics of the lever arm rotation and transient force development in muscle provides new insight into how myosin both generates and responds to muscle force.

Actins↗
PubMed2005

Stochastic high-speed rotation of Escherichia coli ATP synthase F1 sector: the epsilon subunit-sensitive rotation.

The gamma subunit of the ATP synthase F(1) sector rotates at the center of the alpha(3)beta(3) hexamer during ATP hydrolysis. A gold bead (40-200 nm diameter) was attached to the gamma subunit of Escherichia coli F(1), and then its ATP hydrolysis-dependent rotation was studied. The rotation speeds were variable, showing stochastic fluctuation. The high-speed rates of 40- and 60-nm beads were essentially similar: 721 and 671 rps (revolutions/s), respectively. The average rate of 60-nm beads was 381 rps, which is approximately 13-fold faster than that expected from the steady-state ATPase turnover number. These results indicate that the F(1) sector rotates much faster than expected from the bulk of ATPase activity, and that approximately 10% of the F(1) molecules are active on the millisecond time scale. Furthermore, the real ATP turnover number (number of ATP molecules converted to ADP and phosphate/s), as a single molecule, is variable during a short period. The epsilon subunit inhibited rotation and ATPase, whereas epsilon fused through its carboxyl terminus to cytochrome b(562) showed no effect. The epsilon subunit significantly increased the pausing time during rotation. Stochastic fluctuation of catalysis may be a general property of an enzyme, although its understanding requires combining studies of steady-state kinetics and single molecule observation.

Adenosine Triphosphate↗