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Objectives To evaluate the applicability of MRI for the quantitative assessment of anterior talofibular ligaments (ATFLs) in symptomatic chronic ankle instability (CAI). Methods Between 1997 and 2010, 39 patients with symptomatic CAI underwent surgical treatment (22 male, 17 female, mean age 25.4 years (15 to 40)). In all patients, the maximum diameters of the ATFLs were measured on pre-operative T2-weighted MR images in planes parallel to the path of the ATFL. They were classified into three groups based on a previously published method with modifications: ‘normal’, diameter = 1.0 - 3.2 mm; ‘thickened’, diameter > 3.2 mm; ‘thin or absent’, diameter < 1.0 mm. Stress radiography was performed with the maximum manual force in inversion under general anaesthesia immediately prior to surgery. In surgery, ATFLs were macroscopically divided into two categories: ‘thickened’, an obvious thickened ligament and ‘thin or absent’. The imaging results were compared with the macroscopic results that are considered to be of a gold standard. Results Agreement was reached when comparison was made between groups, based on MRI and macroscopic findings. ATFLs were abnormal in all 39 cases and classified as ten ‘thickened’ and 29 ‘thin or absent’. As to talar tilt stress radiography, a clear cut-off angle, which would allow discrimination between ‘thickened’ and ‘thin or absent’ patients, was not identified. Conclusion MRI is valuable as a pre-operative assessment tool that can provide the quantitative information of ATFLs in patients with CAI. Cite this article Bone Joint Res 2014;3:241–5.

X-ray diffraction studies of ammonium Rochelle salt at T=103K in the polar phase are carried out using the Weissenberg camera with an imaging plate. The crystal structure in the polar phase is successfully determined. The structural description in the polar phase is discussed with the previous report in the non-polar phase of ammonium Rochelle salt. The interatomic distances N(1)-O(1), N(2)-O(4), N(2)-O(5), O(8)-O(2) and O(8)-O(3) change accompanying the phase transition, which do not show a practical temperature dependence in the non-polar phase. The orientation of the tartrate molecule also changes with the phase transition. The superlattice structure in the polar phase is made by the drastic structural change.

The specific heats, which are given with absolute value, of Rochelle salt--ammonium Rochelle salt mixed crystals $({\mathrm{RS}}_{1\ensuremath{-}x}\ensuremath{-}{\mathrm{ARS}}_{x})$ in a region $0.18l~xl~0.9$ have been measured between about 10 K and 300 K by an ac calorimetric method. A very small anomaly was found around the transition for any x. It becomes larger as x increases. The anomalies have been well described using the Landau-type free energy expanded to the sixth order of polarization. It was found that, as x increases, the transition point approaches the tricritical point at which a crossover from the second-order phase transition to the first-order one takes place. Transition entropy has been calculated from the anomalous specific heat. It increases from about $8%$ to about $55%$ of $R\mathrm{ln}2$ with increasing x in the measured region. Very small values for small x in this region suggest the displacivelike character in the phase transition. And the order-disorder motion contributes more and more to the phase transition with increasing x.

The purpose of this study was to evaluate, using MRI, the morphology of normal anterior cruciate ligament (ACL) and ACL grafts when the knee was extended compared with when the knee was flexed. Eighteen normal controls and 22 ACL graft patients were studied. Spin-echo (SE) T1-weighted images (TR 330 ms/TE 15 ms, NEX 1) were obtained with a slice thickness of 3 mm. Oblique sagittal images parallel to the ACL were obtained at various flexed angles of the knee joint. In 12 of the 18 normal controls the ACL appeared convex toward the posterior side when the knee was extended and gradually became straight when the knee was flexed. In 15 of the 22 ACL graft patients the grafts appeared straight when the knee was extended and became convex toward the anterior side when the knee was flexed. It is concluded that the morphological changes seen on MR images of ACL grafts from when the knee is extended to when the knee is flexed are different from those in the normal ACL.

Long range order parameter of Rochelle salt-ammonium Rochelle salt mixed crystal NaK1-K(NH4)xC4H4O6.4H2O, x=0.28 is studied from measuring X-ray Bragg intensity. Additionally the mixed crystal of x=0.27 are studied from observing ferroelectric hysteresys loop. The (050) X-ray Bragg intensity is proportional to (Tc-T) or P2 s. The results give sufficiently good agreement. The critical index β of Ps is obtained to be 0.47 from the hysteresis loop observation, which is almost equal to the value in the mean-field theory. The saturated value of the spontaneous polarization (Ps at T=0 K) is estimated to be 0.57 F. The spontaneous polarization of other mixed crystals with x=0.56, 0.83 are also measured. The results show that the saturated value of the spontaneous polarization of the mixed crystal increases with increment of x in the range about 0.28 < x < 0.90.

The crystal structure of Rochelle salt in the ferroelectric phase has been determined by means of X-ray diffraction. R-factor is 0.069. Large thermal vibrations are observed for all the atoms. The displacements of atoms due to the appearance of the spontaneous polarization are presented, which are parallel to the longest principal axis of the thermal motion ellipsoids and confirm the disordered model proposed Iwata el al. Discussions are made on the importance of the interactions between O(8) atom and K ions for the ferroelectric activity.

Effects of buprenorphine, U-50,488H, naltrexone and lithium chloride on cocaine conditioned place preference were examined. Buprenorphine, a mixed opioid agonist-antagonist, blocked the cocaine-induced place preference. Furthermore, the kappa-receptor agonist U-50,488H and the mu-receptor antagonist naltrexone both antagonized the cocaine preference. U-50,488H or naltrexone alone induced a place aversion in a dose-dependent manner. However, the cocaine-induced conditioned place preference was not blocked by lithium chloride, although the latter induced a conditioned place aversion, indicating that the antagonism of cocaine-induced place preference by U-50,488H or naltrexone does not result from a functional antagonism. These results suggest that mu- and kappa-opioid receptors may be involved in cocaine-induced conditioned place preference.

The specific heat of Rochelle salt–ammonium Rochelle salt (RS1−x–ARSx) mixed crystals for 0.18⩽x⩽0.9 (region III) exhibits a finite jump at the transition to the ferroelectric phase. Any critical behaviour like diverging is not observed. We consider the behaviour of the specific heat around the transition on the basis of Landau theory taking account of fluctuation effects. We also give a consideration from a structural point of view.

Crystal structures of SC(NH2)2 in the paraelectric and ferroelectric phases have been refined at several different temperatures. Details of structural changes through successive phase transitions have been obtained {Pbnm [T> Ti (=202 K)], Pb21m [T< T~ (= 169 K)], Z = 4, Mr = 76-12, /~ = 6"3 cm -~ (295K), F(000)=160, M o K a , A=0-71073A}. Typical crystal data are the following: at 295 K, R = 0.042, ND (number of reflections)=433, a = 5.488 (3), b = 7.663 (4), c = 8.564 (4)/~, V-360-2 (6) A, 3, Dx=1"404gcm-3; at 119K, R = 0.034, NO = 1133, a=5.464(4) , b=7.500(5), c = 8.535 (5) A, V = 349-8 (7) A,3, Ox = 1.445 g cm -3. Contrary to previous results [Elcombe & Taylor (1968). Acta Cryst. A24, 410-420], rigidity of the molecule has been confirmed by thermal motion analysis. It has also been shown that the center of librational motion deviates from the center of mass of the molecule. A good relationship has been noticed between the static displacement of the molecule in the incommensurate phase and the largest component of the librational motion in the nonmodulated phases. Evidence of hydrogen bonding is discussed. assumed to behave as a rigid body, on the basis of the structure analysis of the P and F phases. According to Elcombe & Taylor (1968), the molecule in the P phase at room temperature has almost the same shape as that in the F phase at 110 K. On the other hand, the results obtained from their vibration analysis based on the method given by Cruickshank (1956) showed that the molecules do not vibrate rigidly. In order to understand the mechanism of the successive phase transitions on an atomic scale, it is necessary to investigate the vibrational state of the molecule not only at some particular temperature but also throughout the whole temperature range from the P phase to the F phase. The present authors have pointed out the importance of the short-range interactions between the molecules in the modulated structure (Takahashi et al., 1987, 1988). As an important short-range interaction the S..-H--N type hydrogen bond has been considered. Although there have been several studies on this problem (Takahashi, Schrader, Meier & Gottlieb, 1967; Elcombe & Taylor, 1968; Dove & Lynden-Bell, 1986), its properties have not been fully understood yet. In this study, we also discuss hydrogen bonding in the light of the present data.

The effect of stress memorization technique (SMT) in performance and power reduction is maximized by choosing the appropriate stressor with large stress change by spike RTA. 30% mobility enhancement and 60% reduction of gate leakage have been achieved simultaneously. Stress distribution in channel region for SMT is confirmed to be uniform, hence layout dependency is minimized and performance is maximized in aggressively scaled CMOS with dense gate pitch rule (190 nm) in 45 nm technology node.