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PubMed1997

The Spectrum of Hot Water: Rotational Transitions and Difference Bands in the (020), (100), and (001) Vibrational States

Analysis of the hot H2 16O spectrum, presented by Polyansky et al. (1996, J. Mol. Spectrosc. 176, 305-315), is extended to higher vibrational states. Three hundred thirty mainly strong lines are assigned to pure rotational transitions in the (100), (001), and (020) vibrational states. These lines, which involve significantly higher rotational energy levels than were known previously, are assigned using high-accuracy variational calculations. Transitions in (020) are assigned up to Ka = 18, compared with the maximum Ka of 10 known previously. Crossings of vibration-rotation energy levels result in the observation of extra intensity-stealing transitions. In particular, this leads to the assignment of (020)-(100) and (100)-(020) rotational difference band transitions in addition to the conventional pure rotational lines in (020) and (100) states. These extra lines increase the number of transitions and they are likely to complicate the pure rotational water spectrum in higher excited vibrational states to an even greater extent. A few lines from our previous work on the pure rotational spectrum of hot water in the (000) and (010) vibrational states are also reassigned and some further assignments are made. Copyright 1997 Academic Press. Copyright 1997Academic Press

Journal Article↗

PubMed2000

Sub-Doppler Measurements of the Rotational Spectrum of (13)C(16)O.

The five lowest J rotational transitions of (13)C(16)O have been measured by saturation-dip spectroscopy to an accuracy of about 2 kHz, employing phase-stabilized backward-wave oscillators (BWOs). These highly precise measurements cover the transitions from J = 2 <-- 1 to J = 6 <-- 5 with frequencies ranging from 220 to 661 GHz. For each of the five observed rotational transitions, the narrow linewidths of the saturation dips (about 20 kHz) permitted the resolution of the hyperfine splitting for the first time. This splitting is caused by the (13)C-nuclear spin-rotation interaction yielding a value for the nuclear spin-rotation coupling constant of C(I)((13)C(16)O). If combined with the beam measurements (C(I)((13)C(16)O) = 32.63(10) kHz), a slight J-dependence of the spin-rotation coupling constant can be determined (C(J) = 30 +/- 13 Hz). In addition, we have measured in the Doppler-limited mode several higher J rotational line positions of (13)C(16)O up to 991 GHz with an accuracy of 5 kHz. The two line positions (J = 12 <-- 11 and J = 14 <-- 13) were recorded by multiplying BWO frequency with an accuracy of 100 kHz. The rotational transitions J = 17 <-- 16 and J = 18 <-- 17 were measured with an accuracy between 15 and 25 kHz by using the Cologne sideband spectrometer for terahertz applications COSSTA. Copyright 2000 Academic Press.

Journal Article↗

PubMed1996

Rip hump correction and rotation of the lumbar spine after selective thoracic fusion.

In this study a series of 32 patients with idiopathic scoliosis, managed with selective thoracic fusion, was reviewed. Classified according to King and instrumented with the H-frame, the patients were evaluated for curve correction, rib hump correction and postoperative shift in lumbar rotation. Age and follow-up average 19.4 and 2.4 years, respectively. The 32 patients had an average primary and lumbar curve correction of, respectively, 66% (6.0% correction loss) and 53% (3.4% correction loss). The respective values for postoperative rib hump correction and shift in apical lumbar rotation averaged 8 degrees and 9.4 degrees in type II King curves 4.4 degrees and 3.5 degrees in type III and 11 degrees and -5 degrees in Type IV. Significant differences were noted between the curve types in rib hump correction and shift in lumbar rotation. The study showed that en bloc postoperative rotation of the compensatory lumbar segment, directed towards the rib hump, positively influences rib hump correction. This en bloc rotation of the unfused lumbar segments is induced by the correcting forces applied by the instrumentation. The unfused lumbar spine of a patient with a King type II curve shows a larger lumbar rotation shift and subsequent rib hump correction than that of a patient with a King type III curve. Together with factors such as lateral angulation, rib-vertebra angles and structural limitations, the rotational dynamics of the unfused lumbar spine seem to form an important component in the under-standing and surgical management of scoliosis.

Adult↗

PubMed1978

Methodological problems in the measurement of drug-induced rotational behaviour: continuous recording reveals time-course differences undetected by previous techniques.

Rats were lesioned unilaterally in the medial forebrain bundle with either the catecholamine neurotoxin 6-hydroxydopamine or the indoleamine neurotoxin 5,6-dihydroxytryptamine. Their rotational responses in automated rotameters to a challenge with the dopamine-receptor agonist apomorphine were compared using four different techniques in current use, and by assessment of complete rotation curves using both conventional statistical procedures and elementary computer-derived elements of curvature. The rotational responses of the two groups, characterized neurochemically by identical depletions of striatal dopamine but with a greater depletion of striatal 5-hydroxytryptamine in 5,6-dihydroxytryptamine-lesioned animals, were indistinguishable using each of the four current techniques. Assessment of rotation curves by both methods revealed significant differences between the two groups, characterised by faster onset and offset of the rotational response in 5,6-dihydroxytryptamine-lesioned animals. Some current techniques may implicitly exclude the detection of such time-course differences in rotational behaviour. Assessment of complete rotation curves may best allow valid comparisons between experimental groups.

5,6-Dihydroxytryptamine↗

PubMed1989

The influence of the rotational energy of a flywheel on the load pulse sum during pedalling on a cycle ergometer.

Employing seven male subjects, the influence of four different ergometer flywheels with the moments of inertia at the crankshaft (J') = 5.5, 10.5, 16.5, and 19.5 kg.m2 on 6-min load pulse sum (LPS), the heart rate integrated over 6-min was investigated. The J' was demonstrated to influence LPS at each of the corresponding rotational energies of the flywheels (75, 144, 226 and 276 J at 50 rev.min-1) in the four work-load steps (50, 100, 150 and 200 W). Between the values J' = 5.5 kg.m2 and 10.5 kg.m2 the LPS decreases, to rise again in the range J' = 10.5 kg.m2-19.5 kg.m2. For equal work-loads the minimum LPS was reached at a J' of 10.5 kg.m2. For the workloads of 100, 150 and 200 W it was possible to show statistically significant differences. The moment of inertia of ergometer flywheels J has a smoothing effect on the fluctuations of the rotational speed which are unavoidable during work on a cycle ergometer. The flywheel stores the leg forces acting on the pedals as rotational energy and opposes any rotational acceleration. If the J used is too small, equalization of the fluctuations of the rotational speed remains unsatisfactory. Flywheels with larger J require larger torques at the crankshaft for acceleration. For the most effective delivery of work to a cycle ergometer, an optimal rotational energy of the flywheel was found. For equal physical work, smaller or larger rotational energies require a larger expenditure of biological energy. A J' = 11 +/- 2 kg.m2 was incorporated into the draft for the German standard DIN 13,405 -- cycle-type ergometers.

Adult↗

PubMed1999

Subacromial space width changes during abduction and rotation--a 3-D MR imaging study.

The objectives of this study were to determine systematic changes of the normal subacromial space width during abduction and rotation, and to analyze the spatial relationship of the supraspinatus muscle with the acromion and clavicle. 12 healthy volunteers were imaged by an open MR scanner in 5 different positions of abduction and in 3 positions of rotation. After three dimensional (3D) reconstruction and 3D Euclidian distance transformation, the minimal spatial distances between the humerus and the acromion and the humerus and clavicle were computed. The minimal acromio-humeral distance decreased significantly from 30 degrees of abduction (mean 7.0 mm +/- 1.6 mm) to 120 degrees (mean 3.9 mm; +/- 1.8 mm; p < 0.0001). At 30 degrees, the minimal distance penetrated the supraspinatus, whereas at 120 degrees it was always located lateral to the supraspinatus tendon. At 90 degrees with internal rotation (7.6 mm, +/- 2.3 mm) the minimal acromio-humeral distance was larger than in neutral rotation (5.4 mm, +/- 2.3 mm) or external rotation (4.4 mm, +/- 2.2 mm; p < 0.05), but it penetrated the supraspinatus tendon at its most vulnerable part, reaching the acromion at its anterior inferior border. We conclude that the subacromial space width changes during abduction and rotation and that the supraspinatus is in closest contact to the anterior inferior border of the acromion in 90 degrees of abduction with 45 degrees internal rotation. These values obtained in volunteers can be used as a basis for further investigations in patients with the impingement syndrome.

Acromion↗

PubMed1996

Subunit rotation in F0F1-ATP synthases as a means of coupling proton transport through F0 to the binding changes in F1.

The rotation of an asymmetric core of subunits in F0F1-ATP synthases has been proposed as a means of coupling the exergonic transport of protons through F0 to the endergonic conformational changes in F1 required for substrate binding and produce release. Here we review earlier evidence both for and against subunit rotation and then discuss our most recent studies using reversible intersubunit disulfide cross-links to test for rotation. We conclude that the gamma subunit of F1 rotates relative to the surrounding catalytic subunits during catalytic turnover by both soluble F1 and membrane-bound F0F1. Furthermore, the inhibition of this rotation by the modification of F0 with DCCD suggests that rotation in F1 is obligatorily coupled to rotation in F0 as an integral part of the coupling mechanism.

Binding Sites↗

PubMed1998

The role of striatal dopaminergic mechanisms in rotational behavior induced by phencyclidine and phencyclidine-like drugs.

Phencyclidine (PCP) and phencyclidine-like drugs (TCP, dexoxadrol, MK-801, and SKF 10,047) were evaluated for their ability to induce rotational behavior in rats with unilateral 6-OHDA lesions of the medial forebrain bundle and for their ability to alter striatal dopamine (DA) overflow with microdialysis procedures. All of the compounds tested produced rotational behavior ipsilateral to the lesion, suggesting that they were enhancing extracellular dopamine in the intact striatum. The microdialysis studies, however, did not support this contention. There appeared to be a complete dissociation between the ability of the five compounds to produce ipsilateral rotations and their ability to enhance extracellular dopamine levels in the striatum. PCP was the only compound able to elicit significant increases in striatal dopamine overflow following i.p. injections and also produce dramatic rotational behavior. MK-801 was the most potent compound in enhancing rotational output while it had no effect at all on striatal dopamine overflow. Dexoxadrol also produced significant rotational output without having any effect on extracellular levels of dopamine following i.p. injections. TCP and SKF 10,047, at doses which produced significant rotational behavior, only elevated dopamine 16% and 12%, respectively, at peak effect. It is most parsimonious to conclude that the effects of PCP-like drugs on nigro-striatal function are mediated through their ability to act as indirect NMDA receptor antagonists and not through their ability to alter striatal dopamine activity.

Animals↗

PubMed2000

Impacts of rotational grazing and riparian buffers on physicochemical and biological characteristicsof southeastern Minnesota, USA, streams.

We assessed the relationship between riparian management and stream quality along five southeastern Minnesota streams in 1995 and 1996. Specifically, we examined the effect of rotationally and continuously grazed pastures and different types of riparian buffer strips on water chemistry, physical habitat, benthic macroinvertebrates, and fish as indicators of stream quality. We collected data at 17 sites under different combinations of grazing and riparian management, using a longitudinal design on three streams and a paired watershed design on two others. Continuous and rotational grazing were compared along one longitudinal study stream and at the paired watershed. Riparian buffer management, fenced trees (wood buffer), fenced grass, and unfenced rotationally grazed areas were the focus along the two remaining longitudinal streams. Principal components analysis (PCA) of water chemistry, physical habitat, and biotic data indicated a local management effect. The ordinations separated continuous grazing from sites with rotational grazing and sites with wood buffers from those with grass buffers or rotationally grazed areas. Fecal coliform and turbidity were consistently higher at continuously grazed than rotationally grazed sites. Percent fines in the streambed were significantly higher at sites with wood buffers than grass and rotationally grazed areas, and canopy cover was similar at sites with wood and grass buffers. Benthic macroinvertebrate metrics were significant but were not consistent across grazing and riparian buffer management types. Fish density and abundance were related to riparian buffer type, rather than grazing practices. Our study has potentially important implications for stream restoration programs in the midwestern United States. Our comparisons suggest further consideration and study of a combination of grass and wood riparian buffer strips as midwestern stream management options, rather than universally installing wood buffers in every instance. RID="" ID="" The Unit is jointly sponsored by the US Geological Survey, Biological Resources Division; the Minnesota Department of Natural Resources; the University of Minnesota; and the Wildlife Management Institute.

Journal Article↗

PubMedDate not supplied

Percutaneous vertebroplasty: preliminary experiences with rotational acquisitions and 3D reconstructions for therapy control.

Percutaneous vertebroplasty (PVP) is carried out under fluoroscopic control in most centers. The exclusion of implant leakage and the assessment of implant distribution might be difficult to assess based on two-dimensional radiographic projection images only. We evaluated the feasibility of performing a follow-up examination after PVP with rotational acquisitions and volumetric reconstructions in the angio suite. Twenty consecutive patients underwent standard PVP procedures under fluoroscopic control. Immediate postprocedure evaluation of the implant distribution in the angio suite (BV 3000; Philips, The Netherlands) was performed using rotational acquisitions (typical parameters for the image acquisition included a 17-cm field-of-view, 200 acquired images for a total angular range of 180 degrees ). Postprocessing of acquired volumetric datasets included multiplanar reconstruction (MPR), maximum intensity projection (MIP), and volume rendering technique (VRT) images that were displayed as two-dimensional slabs or as entire three-dimensional volumes. Image evaluation included lesion and implant assessment with special attention given to implant leakage. Findings from rotational acquisitions were compared to findings from postinterventional CT. The time to perform and to postprocess the rotational acquisitions was in all cases less then 10 min. Assessment of implant distribution after PVP using rotational image acquisition methods and volumetric reconstructions was possible in all patients. Cement distribution and potential leakage sites were visualized best on MIP images presented as slabs. From a total of 33 detected leakages with CT, 30 could be correctly detected by rotational image acquisition. Rotational image acquisitions and volumetric reconstruction methods provided a fast method to control radiographically the result of PVP in our cases.

Aged↗

PubMed2002

Relationship between the maximum flexion-internal rotation test and the torn acetabular labrum of a dysplastic hip.

To determine the relationship between pain at flexion-rotation and the status of a labral tear in patients with dysplastic hips, physical examination maneuvers and hip arthroscopy were carried out in 59 patients with dysplastic osteoarthritis (5 men and 54 women; mean age, 41 years; range, 16 to 64 years). Between January 1998 and June 2000, these patients underwent 60 hip arthroscopies at Kyushu University Hospital. All hip joints arthroscoped demonstrated incomplete or complete detaching tears of the acetabular labrum in one portion of the weight-bearing area. Twenty-three patients (39%) experienced pain during the maximum flexion-internal rotation test; 16 patients (27%) showed a positive result for the maximum flexion-external rotation test. There was no statistically significant relationship between the results of the maximum flexion-external rotation test and the arthroscopic findings of labral tears. A positive maximum flexion-internal rotation test result, however, correlated well with incomplete detaching tears in the posterosuperior portion of the acetabular labrum. In contrast, a complete detaching tear of the posterosuperior labrum was associated with a negative maximum flexion-internal rotation test result. The maximum flexion-internal rotation test is useful for assessing the magnitude of a labral tear in the posterosuperior portion of the acetabular labrum in dysplastic hips.

Acetabulum↗

PubMed1987

Rotational movement (circling) in normal humans: sex difference and relationship to hand, foot and eye preference.

An endogenous asymmetry in striatal dopaminergic function has been identified in rats, and related to spontaneous and drug-induced circling (rotation, turning). We have developed an electronic device for measuring in humans the same kinds of rotational movements observed in rats. Our data indicate that, without being aware of the type of information being obtained, normal men and women rotate preferentially to the left or to the right during a routine day. Women had higher average rates of rotation than men. Males that were consistently right-sided (left-hemisphere dominant) for hand, foot and eye dominance rotated more to the right than to the left, whereas left-hemisphere dominant females rotated more to the left than to the right. Subjects tested on two occasions, 6 weeks apart, exhibited consistent (significantly correlated) rotational preferences--this was much more evident in left-hemisphere dominant than in mixed dominance individuals. In view of similar animal data, the device used in this study may become a useful and objective means for obtaining quantitative information regarding the status of basal ganglia function in humans.

Adolescent↗

PubMed1990

Dopamine receptors mediate drug-induced but not Pavlovian conditioned contralateral rotation in the unilateral 6-OHDA animal model.

Following Pavlovian conditioning treatment sessions with apomorphine, animals receiving the paired treatment showed substantial contralateral rotation when placed without drug into the test environment previously paired to the apomorphine (0.5 mg/kg) injection while animals in the unpaired control treatment showed only ipsilateral rotation. Subsequent tests with the D1 antagonist (SCH 23390), or the D2 antagonist (haloperidol) partially suppressed and the combined D1-D2 antagonists completely suppressed the apomorphine-induced response of contralateral rotation. The identical contralateral rotation response occurring as a Pavlovian conditioned response in the paired apomorphine treatment group was not attenuated by dopamine receptor blockade. In both paired and unpaired groups, the spontaneous ipsilateral rotation response was completely blocked. Thus, non-dopaminergic mechanisms mediate conditioned rotation whereas the drug-induced as well as the spontaneous rotation responses require stimulation of striatal dopamine receptors.

Animals↗

PubMed1985

Moiré patterns: an accurate technique for determination of the locus of the centres of rotation.

This study describes an accurate technique for the determination of the centre of rotation of small angles. The moiré fringe method localizes the centre of rotation by defining two primary fringes, each of which is found by the intersection of three lines. The primary fringes intersect at the centre of rotation at 90 degrees to each other, the angle least likely to produce an error in measurement. By utilizing joints with known centres of rotation, we have found that the method is extremely accurate and reproducible to within 2 mm of the real centre for angular changes as small as 3 degrees. This technique is useful in evaluating whether a joint is a simple hinge, i.e. rotating about a single axis of rotation or whether the joint moves about a changing axis of rotation referred to as a locus or centrode.

Arthrography↗

PubMed1982

Neural control of head rotation: electromyographic evidence.

Electromyograms, representing samples of neurological control signals, can be used to predict head rotation that can be either time optimal or non-time optimal, depending upon a given subject's intent. Kinematic factors such as operating levels in terms of horizontal and vertical position of the head from which horizontal rotations are made, importantly influence the tonic and phasic aspects of the EMG signal. Pairs of head-rotating muscles, splenius and sternocleidomastoideus muscles, demonstrate reciprocal innervation, particularly for time optimal head rotations. Head rotations of the same amplitude but different velocities correlate with pulse height and pulse width of envelopes of the rectified EMG. Rise of the agonistic EMG correlates in detail with rise of the acceleration transient for a given fast or slow head rotation. Our data demonstrate both the optimal control of details of head movements and the influence of the stretch reflex that strongly relates to initial head position and the velocity of the movements around the primary position. The results support the idea of higher level programmed control of head rotation in human subjects.

Electromyography↗

PubMed1994

Reconsidering the 90 degrees head-rotation paradigm used in neuropsychological research: are there reflexive rather than hemispatial effects?

The 90 degrees head-rotation paradigm has often been used in neuropsychological studies to manipulate external hemispace (circumcorporeal space) relative to the head. Under the 90 degrees head-rotation paradigm, the performance of limb and hand movements carried out within the left or right hemispace as defined by head positions relative to the body is likely to be affected by the reflexive effect due to the neck and vestibular afferent inputs elicited by the head rotations, as well as by the hemispatial effect. Using the H-reflex technique, the present study examined whether the reflexive effect on the spinal motoneuron excitability occurred with head rotations under the 90 degrees head-rotation paradigm. The results showed that the amplitudes of H-reflexes evoked on both the thumb flexor and soleus muscles were not affected by head rotations, indicating no reflexive change in the spinal motoneuron excitability for both the thumb and soleus muscles. This finding suggests that the reflexive effect due to neck and vestibular afferent inputs can be ruled out from possible causal factors influencing the motor performance of limb and hand movements performed within the left or right hemispace as manipulated by the 90 degrees head-rotation paradigm.

Adolescent↗

PubMed1991

Alpha-methyltyrosine blocks the expression of rotation classically conditioned with apomorphine.

Rats with unilateral 6-hydroxydopamine lesions of substantia nigra rotate (circle) when placed, undrugged, in the environment in which they have previously been treated with apomorphine. This conditioned rotation, like the unconditioned rotation which acutely follows the administration of apomorphine, is directed away from the side with the lesion, i.e., the rotation is contralateral. Here, rats that had been administered apomorphine weeks earlier were tested, in a crossover design, for the expression of conditioned rotation following treatment with saline and with alpha-methyltyrosine. When administered four hours prior to testing, 100 mg/kg alpha-methyltyrosine significantly antagonized the expression of classically conditioned rotation. In a second group of animals, alpha-methyltyrosine had no effect on the unconditioned rotation induced by 0.05 mg/kg apomorphine.

Animals↗

PubMed1992

Relation of rotation to egocentric and allocentric spatial learning in the rat.

In this experiment, we asked whether the relation between amphetamine-induced rotation and the learning and retention of left-right discrimination extends to allocentric spatial learning or is limited to egocentric spatial tasks. Rotation was established following injections of d-amphetamine sulfate, and rats were classified as nonrotators, midrotators, or strong rotators. Animals were successively trained on navigation in the Morris water maze (allocentric) and delayed spatial alternation in a water T-maze (egocentric). There were no rotation effects in water maze learning but rotators and nonrotators differed significantly in delayed spatial alternation learning but not relearning. Strong rotators learned more slowly than midrotators, clearly implying that rotational bias and directional learning are not linearly related. We show that it is egocentric spatial learning that is facilitated by a nigrostriatal dopamine asymmetry and extend the generality of the left-right discrimination findings.

Amphetamine↗