bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pb-bearing hollandite-type titanates: A first natural occurrence and reconnaissance synthesis study
Authors: Reguir E. P. , Chakhmouradian A. R. , Mitchell R. H. 
Published: January 2004

AbstractSome samples of hollandite-type titanates from the Murun alkaline complex (Yakutia, Russia) contain appreciable amounts of Pb (up to 12.5 wt.% PbO). These titanates occur in a pegmatitic K-feldsparaegirine rock containing subordinate K-rich batisite, titanite, wadeite and other minerals. The Pb-bearing crystals coexist with hollandite-type phases devoid of detectable Pb and zoned from a Kdominant (priderite) core to a Ba-dominant (henrymeyerite) rim. Recalculation of the microprobe analyses on the stoichiometric basis indicates that most of the Fe occurs in this mineral in trivalent form, suggesting the existence of a solid solution between the Ba(Ti6Fe)O16, K2(Ti6Fe)O16 and Pb(Ti6Fe)O16 end-members. The maximum proportion of the latter end-member in the Murun titanates is ∽45 mol.%. The Ba-free compositions [Pb1.0–1.3(Ti,Fe)8O16] and intermediate members of the (Ba1–xPbx)(Ti6Fe)O16 series were synthesized at 1050 –1100ºC. The synthesis products comprise tetragonal hollandites of various stoichiometry intermixed with rutile, a pseudobrookite-type phase and (for the Ba-free compositions) minor macedonite. Electron microprobe analyses of the hollandites indicate that there is a continuous series of compositions between the two hexatitanate end-members, Ba(Ti6Fe)O16 and Pb(Ti6Fe)O16. The crystal structure of one intermediate member was refined by the Rietveld method in space group I4/m, and found to differ from the hollandite archetype (i.e. Pb-bearing Ba manganate) in that Pb is preferentially partitioned into the 2b tunnel site at (0,0,½), whereas Ba is partitioned into the larger 4e site at (0,0,∽0.8).
Neural Control of Three‐Dimensional Eye and Head Posture
Authors: KLIER ELIANA M. , CRAWFORD J. DOUGLAS 
Published: January 2004

AbstractThe neural commands for gaze control include not only signals that drive the eyes and head from one point to the next, but also those that hold the eyes and head steady at the end of each movement. Studies using microstimulation and chemical inactivation techniques, in head‐fixed and head‐free macaques, were used to investigate the role of the interstitial nucleus of Cajal (INC) in the production of the latter, tonic signals. The right INC was found to control clockwise‐up and clockwise‐down components of both eye and head orientation, whereas the left INC was found to control the counterclockwise‐up and counterclockwise‐down components. Temporary inactivation of the INC left the eyes and head unable to hold their final torsional and vertical positions after each gaze shift. Thus, the INC is strongly implicated in the production of the tonic, step‐like commands that maintain eye and head orientations between gaze shifts. In addition, these studies also found that the INC represents the torsional and vertical commands for eye and head orientation using different coordinate coding strategies, optimally matched to the different three‐dimensional postural constraints observed in the eye and head.
Dynamic Modulation of Ocular Orientation during Visually Guided Saccades and Smooth‐Pursuit Eye Movements
Authors: HESS BERNHARD J.M. , ANGELAKI DORA E. 
Published: January 2004

AbstractRotational disturbances of the head about an off‐vertical yaw axis induce a complex vestibuloocular reflex pattern that reflects the brain's estimate of head angular velocity as well as its estimate of instantaneous head orientation (at a reduced scale) in space coordinates. We show that semicircular canal and otolith inputs modulate torsional and, to a certain extent, also vertical ocular orientation of visually guided saccades and smooth‐pursuit eye movements in a similar manner as during off‐vertical axis rotations in complete darkness. It is suggested that this graviceptive control of eye orientation facilitates rapid visual spatial orientation during motion.
Morphological Properties of Vestibulospinal Neurons in Primates
Authors: BOYLE RICHARD , JOHANSON CURT 
Published: January 2004

AbstractThe lateral and medial vestibulospinal tracts constitute the major descending pathways controlling extensor musculature of the body. We examined the axon morphology and synaptic input patterns and targets in the cervical spinal segments from these tract cells using intracellular recording and biocytin labeling in the squirrel monkey. Lumbosacral projecting cells represent a private, and mostly rapid, communication pathway between the dorsal Deiters' nucleus and the motor circuits controlling the lower limbs and tail. The cervical projecting cells provide both redundant and variable synaptic input to spinal cell groups, suggesting both general and specific control of the head and neck reflexes.
The Role of the Fastigial Nucleus in Saccadic Eye Oscillations
Authors: HELMCHEN CHRISTOPH , RAMBOLD HOLGER , ERDMANN CHRISTIAN , MOHR CHRISTIAN , SPRENGER ANDREAS , BINKOFSKI FERDINAND 
Published: January 2004

AbstractFor the first time, we provide functional magnetic resonance imaging evidence for a recent hypothesis that saccadic oscillations in opsoclonus may result from a disinhibition of the cerebellar fastigial nuclei. Two patients with severe opsoclonus were examined during fixation in the light and during eye closure and in darkness where opsoclonus disappeared. Their activation during opsoclonus was compared with 10 healthy subjects performing visually guided and self‐paced saccades in the light and darkness. In contrast to the control subjects, the patients showed a strong bilateral midline cerebellar activation that involved the deep cerebellar nuclei. This is probably not just a secondary finding in the fastigial nuclei due to the high frequent saccadic activity because there was, concomitantly, no oculomotor vermal activation, which is normally seen in healthy subjects. We propose that cerebellar activation of the fastigial nuclei may cause opsoclonus via their projections to the brainstem saccadic generator.
Vestibular Signals of Posterior Parietal Cortex Neurons during Active and Passive Head Movements in Macaque Monkeys
Authors: KLAM FRANÇOIS , GRAF WERNER 
Published: January 2004

AbstractThe posterior parietal cortex may function as an interface between sensory and motor cortices and thus could be involved in the formation of motor plans as well as abstract representations of space. We have recorded from neurons in the intraparietal sulcus, namely, the ventral and medial intraparietal areas (VIP and MIP, respectively), and analyzed their head‐movement‐related signals in relation to passive and active movements. To generate active head movements, we made the animals track a moving fixation spot in the horizontal plane under head‐free conditions. When under certain circumstances the animals were tracking the fixation spot almost exclusively via head movements, a clear correlation between neuronal firing rate and head movement could be established. Furthermore, a newly employed paradigm, the “replay method,” made available direct comparison of neuronal firing behavior under active and passive movement conditions. In such case, the animals were allowed to make spontaneous head movements in darkness. Subsequently, the heads were fixed and the previously recorded active head‐movement profile was reproduced by a turntable as passive stimulation. Neuronal responses ranged from total extinction of the vestibular signal during active movement to presence of activity only during active movement. Furthermore, in approximately one‐third of the neurons, a change of vestibular on‐direction depending on active versus passive movement mode was observed, that is, type I neurons became type II neurons, etc. We suggest that the role of parietal vestibular neurons has to be sought in sensory space representation rather than reflex behavior and motor control contexts.
Inhibitory Interhemispheric Visuovisual Interaction in Motion Perception
Authors: BRANDT THOMAS , MARX ESTHER , STEPHAN THOMAS , BENSE SANDRA , DIETERICH MARIANNE 
Published: January 2004

AbstractFindings of an earlier functional magnetic resonance imaging (fMRI) study that coherent motion stimulation of the right or left visual hemifield exhibited negative signal changes (deactivations) in the primary visual cortex and the lateral geniculate nucleus contralateral to the stimulated hemisphere were evaluated to determine the functional significance of this contralateral inhibition of the visual system. Fourteen subjects participated in a psychophysical study on the perception of single object motion (0.4°/s) in one visual hemifield with or without concurrent coherent motion stimulation of the contralateral hemifield. Mean detection times for horizontal object motion (0.5 ± 0.19 vs. 0.61 ± 0.22 s) and vertical object motion (0.53 ± 0.19 vs. 0.72 ± 0.34 s) were significantly prolonged during concurrent motion pattern stimulation in the contralateral hemifield. These data support the interpretation that the deactivation of neuronal activity in the visual system found by fMRI is associated with a functional decrement in the sensitivity needed to perceive motion and may reflect transcallosal attentional shifts between the two hemispheres.
Spatial Memory Deficits in Patients with Chronic Bilateral Vestibular Failure
Authors: SCHAUTZER FRANZ , HAMILTON DEREK , KALLA ROGER , STRUPP MICHAEL , BRANDT THOMAS 
Published: January 2004

AbstractThe role of the vestibular system for navigation and spatial memory has been demonstrated in animals but not in humans. Vestibular signals are necessary for location‐specific “place cell” activity in the hippocampus which provides a putative neural substrate for the spatial representation involved in navigation. To investigate the spatial memory in patients with bilateral vestibular failure due to NF2 with bilateral neurectomy, a virtual variant (on a PC) of the Morris water task adapted to humans was used. Significant spatial learning and memory deficits were shown in 12 patients as compared to 10 healthy controls. These data suggest that functional hippocampal deficits manifest due to a chronic lack of vestibular input in these patients. These deficits can even be demonstrated with the subjects stationary, i.e., without any actual vestibular or somatosensory stimulation.
The Human Horizontal Vestibulo‐Ocular Reflex in Response to Active and Passive Head Impulses after Unilateral Vestibular Deafferentation
Authors: HALMAGYI G. M. , BLACK R. A. , THURTELL M. J. , CURTHOYS I. S. 
Published: January 2004

AbstractWe studied the compensatory eye movements made by subjects with unilateral vestibular deficits in response to passive (unpredictable, manually generated) and active (predictable, self‐generated) head impulses. A typical head impulse is a brief, low‐amplitude (15‐20°), high‐velocity (150‐350°/s), high‐acceleration (4000‐6000°/s2), yaw head‐on‐trunk rotation. In the initial 75 ms of the response, the vestibulo‐ocular reflex gain was significantly higher during active head impulses to both ipsilesional and contralesional sides, than during passive impulses. Mean gains were 0.15 (ipsilesional passive), 0.44 (ipsilesional active), 0.5 (contralesional passive), and 0.76 (contralesional active). Differences between active and passive head impulses were present from near the onset of head rotation. The mechanism for producing this behavior is unclear, but the findings could be related to enhanced sensitivity of second‐order neurons during active head impulses. However, even with active movements, there is still a large and statistically significant asymmetry in the eye‐movement responses for ipsilesional as opposed to contralesional head rotations. After 75 ms, rapid corrective eye movements often were generated to reduce any remaining gaze error.
Incomitance of Ocular Rotation Axes in Trochlear Nerve Palsy
Authors: WEBER KONRAD P. , PALLA ANTONELLA , LANDAU KLARA , HASLWANTER THOMAS , STRAUMANN DOMINIK 
Published: January 2004

AbstractStrabismus due to palsy of a single muscle in one eye is always incomitant, which is a consequence of Hering's law of equal innervation. We asked whether this law had similar consequences on the orientation of ocular rotation axes. Patients with unilateral trochlear nerve palsy were oscillated about the nasooccipital (= roll) axis (±35°, 0.3 Hz), and monocularly fixed on targets on a head‐fixed Hess screen. Both the covered and uncovered eyes were measured with dual search coils. The rotation axis of the covered eye (paretic or healthy) tilted more nasally from the line of sight when gaze was directed toward the side of the healthy eye. The rotation axis of the viewing eye (paretic or healthy), however, remained roughly aligned with the line of sight. We conclude that incomitance due to eye muscle palsy extends to ocular rotation axes during vestibular stimulation.
The Critical Role of Velocity Storage in Production of Motion Sickness
Authors: COHEN BERNARD , DAI MINGJIA , RAPHAN THEODORE 
Published: January 2004

AbstractWe propose that motion sickness is mediated through the orientation properties of velocity storage in the vestibular system that tend to align eye velocity produced by the angular vestibulo‐ocular reflex (aVOR) with gravito‐inertial acceleration (GIA). (GIA is the sum of the linear accelerations acting on the head. In the absence of translational accelerations, gravity is the GIA.) We further postulate that motion sickness produced by cross‐coupled vestibular stimulation can be characterized by a metric composed of the disparity between the axis of eye rotation and the GIA, the strength of the response to angular motion, and the response duration, as determined by the central vestibular time constant, that is, by the time constant of velocity storage. The nodulus and uvula of the vestibulocerebellum are likely to be the central sites where the disparity is sensed, where the vestibular time constants are habituated, and where links are made to the autonomic system to produce the symptoms and signs.
Expression of CCAAT/enhancer-binding protein-beta (C/EBPβ) and CHOP in the murine growth plate
Authors: Martos-Rodríguez A. , Santos-Alvarez I. , Campo-Ruíz V. , González S. , García-Ruiz J. P. , Delgado-Baeza E. 
Published: January 2004

Our aim was to evaluate the expression of transcription factors CCAAT/enhancer-binding protein-beta (C/EBPβ) and C/EBP-homologous protein (CHOP) in the growth plate. Proximal tibial epiphyseal growth plates from ten 15-day-old Wistar rats were used. Additionally, anti-proliferating cell nuclear antigen (PCNA), anti-5-bromo-2’-deoxyuridine (BrdU) immunostaining, terminal transferase dUTP nick end-labelling (TUNEL) and nucleolar organiser region-associated proteins (AgNOR) techniques were peformed. The histological morphology of the growth plate from C/EBPβknock-out mice was also analysed. The normal growth plate showed that C/EBPβ and CHOP factors are expressed both in the germinative/ upper proliferative and in the lower proliferative zones. Furthermore, BdrU+ and PCNA+ cells were present exclusively in the germinative and proliferative zones, while TUNEL+ and AgNOR+ cells were seen in all three zones of the growth plate. Acellular areas, hypocellularity, the increase in cell death and anomalies in the architecture of the cell columns were observed in the growth plates of C/EBPβ (−/ −) knockout mice. We suggest that C/EBPβ and CHOP transcription factors may be key modulators participating in the chondrocyte differentiation process in the growth plate.
The peroneus quartus muscle
Authors: Zammit J. , Singh D. 
Published: January 2004

Whilst a few studies have associated various symptoms with the presence of a peroneus quartus muscle in the peroneal compartment of the leg, little is known of the clinical relevance of this muscle. We dissected 102 cadaver legs and reviewed the magnetic resonance images of 80 patients with symptoms from the ankle. The peroneus quartus, with a number of different attachments, was present in 6.6% of the legs. It most commonly arose from the peroneus brevis muscle and inserted into the retrotrochlear eminence of the calcaneum. Associated pathology included a longitudinal tear in the tendon of peroneus brevis, possible peroneal tendon subluxation or dislocation, and a prominent retrotrochlear eminence. On the MR scans its presence was associated with pain and weakness of the ankle. Orthopaedic surgeons and radiologists should be aware of the possible presence of the peroneus quartus muscle, not only because of possible associated pathology, but also for its potential use for surgical reconstruction.
A modified system of stress radiography for patellofemoral instability
Authors: Fukui N. , Nakagawa T. , Murakami S. , Hiraoka H. , Nakamura K. 
Published: January 2004

Axial radiographs were obtained under valgus and external rotation stress at 45° of knee flexion with and without contraction of the quadriceps muscle in order to assess the dynamics of patellar subluxation or dislocation. The radiography was performed on 82 knees in 61 patients with patellofemoral instability, and on 44 normal knees. The lateral patellofemoral angle and the congruence angle were measured and compared with the conventional Merchant views. Both parameters showed greater differences between symptomatic and normal knees on the stress radiographs obtained without quadriceps contraction. There was a major difference in the lateral patellofemoral angles between the groups, which clearly distinguished symptomatic knees from normal controls. Congruence angles on stress radiography had a significant correlation with the functional scores obtained after a period of conservative treatment and a positive correlation with the frequency of patellar subluxation. When the quadriceps contracted, two patterns of patellar shift were observed. While the patella reduced into the trochlear groove in all normal knees and about 70% of the symptomatic knees, contraction of the quadriceps caused further subluxation of the patella in the remaining symptomatic knees. All the knee joints which showed this displacement failed to respond to conservative treatment and eventually required surgical treatment. Thus, this technique of stress radiography is a simple, cost-effective and useful method of evaluating patellar instability and predicting the prognosis.
The influence of immediate surgical treatment of proximal femoral fractures on mortality and quality of life
Authors: Dorotka R. , Schoechtner H. , Buchinger W. 
Published: January 2004

We compared the mortality and outcome of 182 patients with proximal fractures of the femur after immediate and delayed surgical treatment. Seventy-nine patients were operated upon within six hours of the fracture (group 1) and 103 patients were operated upon after this period of time (group 2). At six months follow-up, group 1 had a significantly lower mortality rate. There was a good outcome in both groups with no differences in the outcome. Neither surgical nor anaesthetic factors appeared to have influenced mortality. The subdivision of groups revealed that patients operated on within 24 hours had a better outcome than those whose surgery was delayed. Although there may have been a bias, as patients were not randomly assigned to immediate or delayed surgical treatment, the data suggest that early stabilisation may be associated with a lower mortality rate. Even with pre-clinical delays of more than six hours early treatment should still be attempted, as better results seem to be achieved after 24 hours compared to a later time in our patients.
Surgical treatment of lumbar disc herniation in elderly patients
Authors: Fujii K. , Henmi T. , Kanematsu Y. , Mishiro T. , Sakai T. 
Published: January 2004

Between 1995 and 1999, 12 patients aged 65 years or more (mean 70.2) with lumbar disc herniation, underwent partial laminectomy and nucleotomy. The results were compared with those of 25 younger patients aged between 20 and 40 years (mean 30.1), who underwent the same surgical procedure. The Japanese Orthopedic Association (JOA) score was used to assess the clinical outcome. The minimum follow-up was 12 months. The pre- and post-operative total JOA scores and the rate of improvement of the JOA score were not significantly different between the elderly (11.1, 24.3 points, and 74.1%), and the younger group (11.6, 26.4 points and 84.5%). The results of this study indicate that the outcome of lumbar discectomy in elderly patients is as good as in younger patients.
TENSIONS IN RECENT SINO-JAPANESE RELATIONS
Authors: Wan Ming 
Published: February 2004

Abstract
This paper examines the unusual case of the May 2002 Shenyang Incident. Acting out of character, Tokyo confronted China, motivated by cumulative resentment of recent Chinese actions. Beijing, for its part, reacted with restraint, owing to growing confidence in its place in the world and the continuous moderation of Japanese policy since 1998.
Musicology in the "Third Reich": A Preliminary Report
Authors: Gerhard Anselm 
Published: February 2004

Recent studies of musicology under the Nazi regime make it plausible to reach some conclusions, drawing particularly on four case studies: Heinrich Besseler, Friedrich Blume, Hans Joachim Moser, and (as a counterexample) Alfred Einstein. First, musicology is a small discipline and in 1933 was even smaller, making it particularly open to intrigue. Personal loyalties were more important than political and ideological ones; patriarchal teacher-student relations had more weight than factions born of clashes between rival groups within the National Socialist regime.
Second, musicology is a decidedly German discipline: Into the 1930s, it existed as a university subject largely in the three German-speaking countries. A tradition of musicological scholarship that was firmly convinced of the preeminence of its own national heritage did not need to accommodate itself in the first place to the German jingoism of the National Socialists. On the contrary, scholars had perhaps more freedom because their national orientation could never seriously be doubted.
Third, music as a conceptless art was not easily subsumed under "racial" and "völkisch" constructs. Many during the "third Reich" tried to explain European music history by drawing on the spirit of contemporary studies of race, but they often had to admit the difficulty if not the utter failure of the enterprise. In comparison with other disciplines it is noticeable that only those outside the university formulated overwhelmingly racist accounts of music history, and they could not pass muster with their nationalist or National Socialist colleagues.
Finally, university musicologists, no less than their colleagues active in the Amt Rosenberg or in the Propagandaministerium, shared responsibility for a discourse of exclusion and völkisch terror both inside and outside the country. Culpability must be investigated individually, but a look at the field as a whole makes it possible to understand how after 1945, musicologists in the two Germanys and Austria could without difficulty resume work broken off before the final collapse of the National Socialist regime.