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PubMed1990

Theoretical calculation of the longitudinal spherical aberration of rigid and soft contact lenses.

Although previous investigators have attempted to calculate the longitudinal spherical aberration inherent in soft and rigid contact lenses both on and off the eye, the use of inappropriate assumptions on which to base their calculations has left the problem unresolved. In this study, the longitudinal spherical aberration of both soft and rigid contact lenses was calculated surface by surface both in air and on the eye using a two-dimensional, exact ray tracing program. The erroneous assumptions made by previous investigators were avoided by using an elliptical model for the anterior corneal surface and assuming that the posterior surfaces of soft lenses aligned exactly with the anterior corneal surface after flexure onto the eye. The results demonstrated that, with a 6-mm pupil, contact lenses induce significant levels of spherical aberration in the ocular system for soft lenses of back vertex power greater than +3.00 D or -6.00 D and for rigid lenses of powers more positive than -3.00 D. It is suggested that visual disturbance due to induced spherical aberration has not been a major clinical problem in the past because these conditions fall outside those experienced by a large proportion of the contact lens-wearing public.

Computer Simulation↗
PubMed1993

Transient rigid lens-induced striae in keratoconus.

We have observed spontaneous development of striae and an enhanced visibility of them after placing rigid gas permeable contact lenses on six patients suspected of having early keratoconus. These fine folds subside upon removal of the rigid lens. This observation assists clinicians with the differential diagnosis of irregular astigmatism when the definitive biomicroscopic signs of keratoconus are either not present or are so subtle that their presence is questionable. Although these striae may not occur in all patients suspected of having early keratoconus, we find that observation of the posterior cornea in the presence of a rigid lens will often confirm the diagnosis of keratoconus. We have not seen similar striae in patients whose clinical presentation is not consistent with early keratoconus.

Adolescent↗
PubMed1996

Palpebral aperture sizes of rigid and soft contact lens wearers compared with nonwearers.

Previous studies have shown that contact lens wear may affect palpebral aperture size (PAS). In this study, 74 wearers of rigid lenses were matched for sex and age with soft lens wearers and nonwearers. Partial face photographs were taken of all subjects, in the case of contact lens wearers, after lens removal. PAS was determined by measuring the resulting 35-mm transparencies on a Mitutoya profile projector. The mean PAS of the rigid lens wearers (9.76 +/- 0.99 mm) was found to be significantly smaller than that of the soft lens wearers (10.24 +/- 0.94 mm) and the nonwearers (10.10 +/- 1.11 mm) (p = 0.0154, analysis of variance). There was no significant difference between the PAS of soft lens wearers and nonwearers. This study supports the hypothesis that rigid lens wear causes a decrease in PAS.

Adult↗
PubMed1997

Rigid internal fixation with lateral mass plates in multilevel anterior and posterior reconstruction of the cervical spine.

STUDY DESIGN: A retrospective clinical and radiographic analysis was performed on 17 patients with multilevel cervical disease who were treated with anterior and posterior reconstruction with a new rigid, segmental, internal fixation system applied to the lateral masses. OBJECTIVES: To determine the applicability, safety, and clinical efficacy of an instrumentation system used as a cervical lateral mass plate in the management of complex spinal disorders. SUMMARY OF BACKGROUND DATA: Cervical disorders involving three or more levels present a difficult reconstruction problem, especially if the posterior elements are deficient. Segmental fixation with lateral mass plating provides an alternative method to situations that would otherwise require a halo. METHODS: Seventeen patients treated by a single surgeon underwent cervical reconstruction surgery involving three or more levels. All patients had anterior decompression and reconstruction and a posterior fusion with rigid internal fixation with a device applied to the lateral masses of the cervical vertebrae. Patients were reviewed clinically and radiographically to determine the efficacy and safety of this method of fixation. RESULTS: Of the 15 patients with adequate follow-up data that were studied, the condition of 13 patients, (87%) was improved, that of one patient (6.7%) was the same, and that of another (6.7%) was worse after surgical intervention. Sagittal alignment was restored to within 5 degrees of the preoperative lordosis in active extension by the modified Cobb method and the Gore method. No patient had radiographic nonunion. One patient had a sensory radiculopathy associated with an overpenetrated lateral mass screw that partially resolved after hardware removal. One patient had asymptomatic loosening of a C7 lateral mass screw. CONCLUSIONS: Segmental posterior fixation with lateral mass plating provides more rigid immobilization than traditional techniques, allows restoration and maintenance of spinal alignment, obviates the need for halo immobilization, and is associated with a low incidence of neurovascular injury.

Adult↗
PubMed1998

The effects of rigid spinal instrumentation and solid bony fusion on spinal kinematics. A posterolateral spinal arthrodesis model.

STUDY DESIGN: Spinal kinematics after the implementation of rigid spinal instrumentation or the achievement of a solid fusion was studied using a sheep posterolateral spinal arthrodesis model. OBJECTIVE: To investigate the effects of rigid spinal instrumentation or solid fusion on spinal kinematic parameters. SUMMARY OF BACKGROUND DATA: Numerous studies have attempted to define spinal instability in terms of kinematics. Recent in vitro studies have documented the neutral zone, or a measure of spinal laxity, as more sensitive to spinal instability than the range of motion. METHODS: Seven skeletally mature sheep underwent a single-level posterolateral lumbar arthrodesis using autologous bone graft augmented with transpedicular screw fixation. The animals were killed 4 months after surgery. The identical surgical procedures were performed in seven sheep cadaveric spines, which served as acute postoperative controls. Each functional spinal unit was tested biomechanically before and after hardware removal. The experimental control groups consisted of destabilized spines and spines that underwent transpedicular screw fixation alone, whereas the fusion groups included spines that underwent posterolateral fusion alone or posterolateral fusion with instrumentation. RESULTS: Rigid instrumentation and solid fusion significantly decreased the neutral zone and range of motion in all testing modes. In axial rotation and lateral bending, solid fusion reduced the range of motion significantly more than transpedicular screw fixation alone. However, in all testing modes, the neutral zones showed no statistical difference between transpedicular screw fixation alone and fusion groups. CONCLUSIONS: The range of motion was an equivalent or better indicator of fixation or fusion stability compared with the neutral zone. Moreover, the immediate postoperative fixation stability, even if using transpedicular screw fixation, was less than the stability present after a solid fusion.

Animals↗
PubMed2001

Multiple vertebral osteotomies in the treatment of rigid adult spine deformities.

STUDY DESIGN: Retrospective review of the clinical and radiographic results in adult revision spine deformity surgery using the techniques of osteotomies to effect spine balance and curve correction. OBJECTIVES: To assess the efficacy of multiple vertebral osteotomies in correction of rigid spine deformities in adult patients undergoing revision surgery. METHOD: The records and radiographs of 27 adult patients with idiopathic scoliosis who underwent revision surgery requiring anterior release (discectomy and/or osteotomy) and posterior osteotomy to correct rigid spinal deformities were retrospectively reviewed. RESULTS: All 27 patients were available for follow-up evaluation. Fifteen patients had anterior discectomies followed by posterior osteotomies, whereas 12 had anterior and posterior osteotomies in staged or sequential (same day) fashion. Diagnosis was idiopathic scoliosis for the index operation. At revision, the primary deformity was flatback deformity in 10 patients and pseudarthrosis with progressive deformity in 17 patients. Eleven patients had predominant sagittal decompensation, 11 patients had multiplanar decompensation, and five patients were balanced. The average number of osteotomies performed anteriorly was 4.3 levels (range, 1-8) and the average number of osteotomies posteriorly was 4.6 levels (range, 1-10). There were a total of nine complications in eight patients including three pseudarthroses (11%), five hardware failures (19%), and one transient neurologic deficit (4%). There were no deep wound infections, deep vein thromboses, pulmonary emboli, or deaths. The average scoliosis correction was 40% (range, 5-81%), whereas the average sagittal balance was corrected 6.5 cm (range, -5-29.5 cm), on average, and coronal balance was corrected 2.5 cm (range, 1-6 cm), on average. CONCLUSION: This study demonstrates multiple vertebral osteotomies (anterior and/or posterior) in the management of rigid adult spine deformities and deformity correction with an acceptable complication rate. Use of vertebral osteotomies for patients undergoing revision spine surgery is a safe and reasonable approach to obtain an arthrodesis.

Adult↗
PubMed2002

The use of short and rigid anterior instrumentation in the treatment of idiopathic thoracolumbar scoliosis: a retrospective review of 24 cases.

STUDY DESIGN: The results of short anterior rigid rod instrumentation used to treat thoracolumbar scoliosis in 24 patients were reviewed retrospectively. OBJECTIVE: To assess the safety and efficiency of anterior correction of thoracolumbar scoliosis using a single rigid rod with segmental fixation. SUMMARY OF BACKGROUND DATA: This method of treatment results from the historical difficulties noted in obtaining adequate correction in both planes for this particular type of curve while saving as many segments as possible. This approach seems to combine the advantages and avoid the limitations of posterior segmental and previous anterior segmental techniques. METHODS: For this study, 24 patients with thoracolumbar scoliosis underwent anterior spinal correction and fusion using a single rigid rod and segmental fixation. Additionally, in five patients, this construct was supplemented by interbody titanium cages. The patients were assessed for the amount of correction obtained in the main curve, and for the spontaneous correction of the compensatory curves above and below. Trunk balance was measured on standing radiographs. The average age of the patients was 17.3 years (range, 10-43 years), and the average follow-up period was 3.6 years (range, 2-4.5 years). RESULTS: Correction of the major curve at follow-up assessment was 54%, with a 73% correction of the instrumented area. The upper compensatory curve showed a 21% correction, and the lower curve a 59% correction. Over the duration of the follow-up period, the instrumented area showed kyphosis progression of 6.5 degrees. The five patients who had insertion of Harms cages tended to have a lower rate of correction. The average number of intervertebral mobile segments fused was 2.9 (range, 2-5 segments). No intraoperative complication occurred in relation to the anterior approach. A temporary sympathectomy effect on the side of the approach was noted in most patients. Two radiologic pseudarthrosis and one loss of fixation at the top of the construct were observed. CONCLUSIONS: Anterior correction and fusion using solid rod instrumentation constitute effective and safe treatment of thoracolumbar scoliosis. As compared with posterior systems, it provides correction and rebalance of the trunk through a shorter fusion segment.

Adolescent↗
PubMed1995

Remodeling dynamics of bone supporting rigidly fixed titanium implants: a histomorphometric comparison in four species including humans.

The long-term maintenance of a rigid bone-implant interface (osseointegration) is the clinical goal of most dental implant systems, although the biological mechanism for retaining a foreign object in living bone is unclear. Little data are available on the physiological turnover (remodeling) of the supporting osseous tissue. The objective of this study was to histomorphometrically assess bone remodeling surrounding rigidly integrated titanium implants in multiple species. Implants, in place from 6 months to 5 years, were recovered from human, monkey, dog, and rabbit subjects. With the use of stereological point-hit and linear-intercept methods, indices of bone formation and resorption were determined. Remarkably similar patterns emerged among all investigated species. Repeated-measures ANOVA showed a 3 to 9 fold increase in remodeling within 1 mm of the bone-implant interface (P<0.001; data expressed as percent turnover / month, mean +/- SEM for n = 3-11). All morphometric indices (percent new bone, percent fluorochrome-labeled bone, percent resorption space) showed similar trends. These data suggest that the physiological mechanism for maintaining rigid osseous integration (osseointegration) is a sustained elevation of remodeling adjacent to the bone-implant interface.

Alveolar Process↗
PubMed2004

A randomized clinical trial of treatment for lumbar segmental rigidity.

STUDY DESIGN: A randomized single-blind clinical trial of facet injections plus exercise, versus exercise alone, in chronic disabling work-related lumbar spinal disorders (CDWRLSD), accompanied by pilot interrater reliability and facet syndrome prevalence studies. OBJECTIVES: To systematically investigate the use of facet injections as an adjunct to supervised lumbar stretching exercises in regaining lumbar range of motion (ROM) following prolonged deconditioning after work-related lumbar injuries. To assess interrater reliability of visual assessment of segmental rigidity (SR), and to evaluate the prevalence of facet syndrome in cases of lumbar SR. SUMMARY OF BACKGROUND DATA: Corticosteroid joint injections have often been used to reduce musculoskeletal inflammation to facilitate joint mobilization in the presence of degenerative arthritis. Lumbar segmental rigidity is a recently described entity usually associated with painful chronic spinal disorders and postoperative spine surgery. Previous work has shown that SR and lumbar ROM improves with a brief intervention consisting of facet injections followed by specific stretching exercises. No systematic study has investigated the potential benefits of a combination of facet injections and exercise over supervised exercises alone to treat lumbar SR. Similarly, no study has assessed the association between SR and the facet syndrome. METHODS: From a group of consecutive patients (n = 421) with CDWRLSD referred for tertiary rehabilitation between November 1999 and January 2001, 70 were noted to have SR on intake physical examination. The first part of this study assessed interrater reliability for detecting SR, and intrarater reliability for 3-segment true lumbar ROM measurements. Patients randomly assigned to participate in supervised stretching exercises with the addition of fluoroscopically guided bilateral facet injections at the involved levels (Group A, n = 36) also underwent facet syndrome prevalence assessment at the time of injection. They were compared to a randomly allocated comparison group (Group B, n = 34) undergoing exercises alone in a single-blind design. Physical therapists saw patients an average of twice per week, providing supervision of a progressive home stretching program. Inclinometric joint ROM was measured at the time of group allocation, and again 5 to 7 weeks later. Validated questionnaires of pain (intensity VAS) and disability (Million VAS) related to the CDWRLSD were provided before and after the interventions. RESULTS: Part 1 reliability and facet syndrome prevalence work revealed that interrater reliability for experienced examiners to detect rigid segments was excellent (Pearson's r = 0.97, P < 0.01). Intrarater 3-joint motion measurement reliability was also good for all sagittal/coronal ROM (Pearson's r = 0.95-0.99, P < 0.01). Only 5 of 29 subjects with SR met criteria for facet syndrome (17%), consistent with prior prevalence studies of unselected patients with low back pain. In Part 2, a large majority of patients in both groups improved from the initial to the post-treatment ROM measurements (the primary outcome criterion of the study). However, a higher proportion of Group A (injection) patients (87%-95%) showed ROM improvement, compared to Group B (exercise only) patients (64%-79%). Group A patients showed a significantly greater ROM improvement in all sagittal and coronal movements, both in absolute terms and percent of initial measurement. No significant differences in pain or disability self-report were found between groups, pre- or postintervention, but both groups showed significant improvement from pre- to postintervention in pain and disability assessments. CONCLUSIONS: The detection of SR and measurement of 3-segment true lumbar ROM by experienced examiners is highly reliable. Only 17% of CDWRLSD patients with lumbar SR met criteria for the facet syndrome, a rate approximately equal to that of unselected low back pain cohorts. This indicates that lumbar SR may be found whether or not pain of facet joint origin is present. In the randomized trial, facet injections significantly increased the percentage of patients with SR showing ROM improvement, as well as the degree of improvement in lumbar mobility after treatment. There is no evidence that facet injections increase the improvements in pain/disability report noted in both groups.

Adrenal Cortex Hormones↗
PubMed2006

Comparison of 1-stage versus 2-stage anterior and posterior spinal fusion for severe and rigid idiopathic scoliosis--a randomized prospective study.

STUDY DESIGN: A randomized prospective study. OBJECTIVE: To compare safety, efficacy, and cost between 1-stage and 2-stage anterior and posterior spinal fusion in treating rigid thoracic adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Retrospective study issued different outcomes comparing 1-stage with 2-stage surgical procedures in treating neuromuscular and congenital scoliosis. A randomized prospective study in AIS has rarely been reported. METHODS.: Twenty-four patients were randomly divided into 2 groups. Group A underwent a 2-stage procedure, group B a 1-stage procedure. Inclusion criteria were: (1) AIS; (2) rigid single thoracic curve, > or =90 degrees on anteroposterior and > or =60 degrees on side bending view; and (3) pulmonary function tests, vital capacity > or =500 mL or FEV1 > or =50%. Exclusion criteria were: (1) curves either <90 degrees on anteroposterior or <60 degrees on bending view; and (2) pulmonary function tests, both vital capacity <500 mL and FEV1 <50%. The mean follow up was 3.3 years (range 2-5.1). Clinical outcomes between the 2 groups were analyzed. RESULTS: A statistical t test demonstrated no significant difference in age (P = 0.299), curves on anteroposterior (P = 0.908), on bending (P = 0.905), after surgery (P = 0.699), and at last follow-up (P = 0.946). No significant difference in blood loss (P = 0.089), transfusion (P = 0.334), operation time (P = 0.172), fusion segments anterior (P = 0.161), posterior (P = 0.546), wound drainage (P = 0.557), thoraco drainage (P = 0.948), and loss of correction at follow-up (P = 0.596). However, significant differences were found in length of stay (P < 0.001), patient cost of hospitalization (P < 0.001) between 2 groups, and curve correction (P < 0.001) in each group. Perioperative complications included 1 patient each with pneumonia, pneumothorax (group A), and ileus (group B). Screw nut loosing was found in 1 patient in group B, but no curve deteriorated. No neurologic deficit occurred in either group. CONCLUSION: A comparison of 1-stage versus 2-stage fusion in treating rigid thoracic curves in AIS did not show significant differences in safety or efficacy but did demonstrate significant difference in length of stay and patient cost.

Adolescent↗
PubMed2005

The biomechanics of keratoconus and rigid contact lenses.

PURPOSE: To examine aspects of the genesis and progression of keratoconus through an analysis of the biomechanical forces associated with this condition, including those generated by rigid contact lenses. METHODS: The biomechanics of applanation tonometry and rigid contact lenses serve as a basis for examining contact lens adherence and the potential for contact lens induced mid peripheral corneal applanation and apical molding with apical clearance fittings. DISCUSSION: Some physiologic and pathologic mechanisms for increases in intraocular pressure are reviewed. The possibility is raised that hard squeeze blinks, for example, could significantly increase the distending forces that bear on the corneal apex in keratoconus and that some apical clearance contact lens fittings could increase the risk of progressive ectasia. Support for these hypotheses is found among healthy eyes and eyes with keratoconus that show increased curvature when apical clearance fittings are worn. CONCLUSIONS: The known risk of scarring responses to excessively flat fitting rigid contact lenses must be balanced against the possible risk of molding and ectasia advancement responses to tight definite apical clearance lenses. Fittings within the range of minimal apical clearance and minimal apical contact (divided support) may be the most appropriate. The appearance and performance of these fittings may be difficult to distinguish clinically. Because some patients may develop pathologic levels of intraocular pressure with vigorous eye rubbing, strong squeeze blinks, inverted body positions, and strenuous muscular effort, patients with, or at risk for, keratoconus, glaucoma, or progressive myopia should be advised of the possible adverse significance of these activities.

Biomechanical Phenomena↗
PubMed2005

The effects of high-Dk rigid contact lens center thickness, material permeability, and blinking on the oxygen uptake of the human cornea.

PURPOSE: The human corneal oxygen uptake responses associated with the static (nonblinking) and dynamic (blinking) wear of five rigid gas-permeable materials with high oxygen permeabilities were determined for three different center thicknesses and compared with the responses for the normal open eye and severe hypoxic stress (static wear of polymethylmethacrylate). METHODS: Corneal oxygen uptake rates were measured with a Clark-type polarographic electrode during two sessions with each of 10 human subjects. Measurements were made on the right eye for the normal open eye (air) and after 5 minutes of static and dynamic wear of polymethylmethacrylate and five rigid gas-permeable contact lens materials: Fluoroperm 92 (paflufocon A, Dk = 92), Fluoroperm 151 (paflufocon D, Dk = 151), 1992 Menicon SF-P (melafocon A, Dk = 102), 1995 Menicon SF-P (melafocon A, Dk = 159), and Menicon Z (tisilfocon A, Dk = 163-250). Lenses were manufactured in three different center thicknesses (0.12, 0.16, and 0.20 mm), with all other parameters remaining constant. Repeated-measures analysis of variance was used and included lens material (five levels), blinking condition (two levels), and lens thickness (three levels) as within-subject effects. RESULTS: Significant differences were found in corneal oxygen responses to lens material (p < 0.001) and lens thickness (p < 0.001), with lenses of lower oxygen permeability and thicker lenses being associated with higher oxygen uptake. No statistically significant differences were noted between static or dynamic wear of the lens materials (p = 0.59). CONCLUSIONS: For those very high Dk rigid lens materials studied here, moderate changes in lens thickness or material permeability may result in modest differences in corneal hypoxic relief, whereas blinking results in no significant improvement to corneal oxygenation.

Adult↗
PubMed2003

Long-term fate of vascularized iliac bone flap as a source for phallic rigidity.

One of the surgical goals of phalloplasty is to obtain sufficient rigidity for sexual penetration. This is also important for patients with erectile dysfunction. Different kinds of techniques have described phalloplasty and obtaining rigidity in patients with erectile dysfunction, but there is no good substitute for the erectile tissue of the penis. The authors used an iliac osteocutaneous flap for phalloplasty and a vascularized bone flap for imitating penile erection. Five patients who had undergone either phalloplasty or correction of erectile dysfunction are presented. Long-term results are promising in adults and the authors advocate using vascularized iliac bone for sufficient rigidity of a (neo)phallus. However, the results are moderate for children who have undergone previous phalloplasty.

Adult↗
PubMed2003

Dynamic rigidity transition.

An inflated closed loop (or membrane) is used to demonstrate a dynamic rigidity transition that occurs when impact energy is added to the loop in static equilibrium at zero temperature. The only relevant parameter in this transition is the ratio of the energy needed to collapse the loop and the impact energy. When this ratio is below a threshold value close to unity, the loop collapses into a high-entropy floppy state, and it does not return to the rigid state unless the impact energy can escape. The internal oscillations are in the floppy state dominated by 1/f(2) noise. When the ratio is above the threshold, the loop does not collapse, and the internal oscillations resulting from the impact are dominated by the eigenfrequencies of the stretched membrane. In this state, the loop can bounce for a long time. It is still an open question whether bouncing will eventually vanish or whether a stationary bouncing state will be reached. The dynamic transition between the floppy and the rigid state is discontinuous.

Journal Article↗
PubMed2003

Existence and stability of rigid photovoltaic solitons in an open-circuit amplifying or absorbing photovoltaic medium.

A different type of photovoltaic soliton is predicted for open-circuit photovoltaic media with a gain provided by two-wave mixing. Such solitons are a result of a double balance, i.e., loss is balanced by gain and diffraction is balanced by nonlinearity that is due to both, photovoltaic effects and two-wave mixing. Exact bright and dark analytical solutions are obtained under the condition that the signal beam is much weaker than the pump beam. Such solitons have fixed amplitude and width for the fixed values of the system parameters and hence are named rigid photovoltaic solitons. When the pump beam is switched to a background illumination, rigid photovoltaic solitons can become previously observed photovoltaic solitons. Numerical simulations show that rigid photovoltaic solitons are stable against small perturbations.

Journal Article↗
PubMed2006

1/f noise and very high spectral rigidity.

It was recently pointed out that the spectral fluctuations of quantum systems are formally analogous to discrete time series, and therefore their structure can be characterized by the power spectrum of the signal. Moreover, it is found that the power spectrum of chaotic spectra displays a 1/f behavior, while that of regular systems follows a 1/f2 law. This analogy provides a link between the concepts of spectral rigidity and antipersistence. Trying to get a deeper understanding of this relationship, we have studied the correlation structure of spectra with high spectral rigidity. Using an appropriate family of random Hamiltonians, we increase the spectral rigidity up to hindering completely the spectral fluctuations. Analyzing the long range correlation structure a neat power law 1/f has been found for all the spectra, along the whole process. Therefore, 1/f noise is the characteristic fingerprint of a transition that, preserving the scale-free correlation structure, hinders completely the fluctuations of the spectrum.

Journal Article↗
PubMed2003

Role of rigidity in the fluid-solid transition.

We examine the fluid-solid transition for a hard-disk system. By counting the near neighbors in the average configurations of a grand-canonical Monte Carlo simulation, this enables us to relate the thermodynamic transition with the rigidity theory, since we find that the coordination number in the fluid-solid transition is close to the coordination number predicted by a mean field rigidity theory, due to dynamical jamming of particles, where the contact region between disks is the radial ring outside a disk with a maximum allowed coordination number that is not bigger than six. Using these ideas, we were able to produce a continuous glass-like transition when nucleation of rigidity is suppressed.

Journal Article↗
PubMed2004

Network rigidity and properties of SiO2 and GeO2 glasses under pressure.

We report in situ studies of SiO2 glass under pressure and find that temperature-induced densification takes place in a pressure window. To explain this effect, we study how rigidity of glasses changes under pressure, with rigidity percolation affecting the dynamics of local relaxation events. We link rigidity percolation in glasses to other effects, including a large increase of crystallization temperature and logarithmic relaxation under pressure.

Journal Article↗