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1.
We investigated retrospectively 132 cases of open wedge high tibial osteotomy using an external fixation device, concentrating on the rate of neurological complications. One group of patients underwent surgery according to the conventional technique (n = 89). The rate of transient neurological complications was 15.7%; 7 months after surgery the rate of persistent deficits was 12.4%. For the second group (n = 43) a modified surgical technique was used that lowered the complication rate significantly (transient deficits 14%, persistent deficits 4.7%). In the modified technique the osteotomy is not performed in the conventional way using an oscillating saw but through consecutive drill holes of increasing diameter followed by osteoclasis. The lower complication rate in the second group is mainly due to the less extensive approach that leads to a smaller number of postoperative tibialis anterior syndromes (type B lesion). No differences were found with type C lesions (extension deficit of D1). No complete peroneal nerve palsy (type A) occurred in either group. We conclude that the reduction of neurological complications in group 2 is related to the less extensive approach of the proposed technique.  相似文献   
2.
V J Modi  T Yokomizo 《Sadhana》1994,19(3):401-426
The concept of moving surface boundary-layer control, as applied to a Joukowsky airfoil, is investigated through a planned experimental programme complemented by numerical studies. The moving surface was provided by rotating cylinders located at the leading edge and/or trailing edge as well as top surface of the airfoil. Results suggest that the concept is quite promising, leading to a substantial increase in lift and a delay in stall. Depending on the performance desired, appropriate combinations of cylinder geometry, location and speed can be selected to obtain favourable results over a wide range of angle of attack. Next, effectiveness of the concept in reducing drag of bluff bodies such as a two-dimensional flat plate at large angles of attack, rectangular prisms and three-dimensional models of trucks is assessed through an extensive wind tunnel test-programme. Results show that injection of momentum through moving surfaces, achieved here by introduction of bearing-mounted, motordriven, hollow cylinders, can significantly delay separation of the boundary-layer and reduce the pressure drag. The momentum injection procedure also proved effective in arresting wind-induced vortex resonance and galloping type of instabilities. A flow visualization study, conducted in a closed-circuit water tunnel using slit lighting and polyvinyl choride tracer particles, adds to the wind-tunnel and numerical investigations. It shows, rather dramatically, the effectiveness of the moving surface boundary-layer control (MSBC). The Sabita Chaudhury Memorial Lecture The models were fabricated in the Mechanical Engineering Workshop. The assistance of M/s E Abell, P Hurren and D Camp in the design and construction of the models is gratefully acknowledged. The investigation was supported by the Natural Sciences and Engineering Research Council of Canada, Grant No. A-2181.  相似文献   
3.
Recently, the demand of the information storage devices with large storage capacity such as Blu-ray Disc and high-definition television is increased. In keeping with this trend, the optical storage devices are also required to have high data transfer rate and large storage capacity. To satisfy these requirements, the actuator for optical disc drive should have a high servo bandwidth to compensate the vibration of optical disc. The servo bandwidth is limited by some flexible modes of the actuator, thus it is essential to make these frequencies of flexible modes to high frequency region. The frequency of flexible mode depends on materials and shape. Stiff materials and simple shape is useful to increase the frequency of flexible mode. In this paper, we suggested a moving magnet type actuator having flexible modes which are happened at high frequency region. Generally, the moving magnet type actuator has an advantage to increase the frequency of flexible mode because the moving magnet type actuator has simple structure and the Young’s modulus of magnet is high. However, large moving mass and inefficiency of Electromagnetic (EM) circuit cut down driving sensitivities of actuator. To improve driving sensitivities, we designed the model with the closed EM circuit for tracking actuation. The design of experiments (DOE) procedure is applied to get proper design parameters and the variable metric method (VMM) which is a technique of optimization is used to improve driving sensitivity. The lens holder is also improved based on the optimization result of EM circuit. And to make up for the low efficiency of EM circuit, the thermal stability is checked on condition that the input current is very high. At last, the final design of moving magnet type actuator is suggested and it is verified that the driving performance and the structural stiffness of the final design is sufficient.  相似文献   
4.
Monosodium glutamate (GluNa)-compounded starch was prepared by heat-moisture treating a mixture of tapioca starch and GluNa. GluNa-compounded starch exhibited a higher gelatinization temperature and reduced swelling and solubility, essentially lower hardness of the granule center, and paste viscosity than those of the heat-moisture treated tapioca starch and the untreated starch. However, its appearance, unit chain length distribution, and α-amylase digestibility were similar to those of the heat-moisture treated tapioca. It is thus concluded that GluNa compounding is useful for providing a unique type of starch that possesses a less swollen and viscous texture than that produced with simple heat-moisture treatment.  相似文献   
5.
PURPOSE: Lamotrigine (LTG) is recognised as effective add-on therapy for focal epilepsies, but this is the first double-blind, placebo-controlled, crossover study in treatment-resistant generalised epilepsy. METHODS: The study consisted of 2 x 8-week treatment periods followed by a 4-week washout period. Patients received doses of either 75 or 150 mg daily, depending on their concomitant antiepileptic drugs (AEDs). Long-term continuation was offered at the end of the study with open-label LTG. RESULTS: Five centres in Australia recruited 26 patients who were having absence, myoclonic, or generalized tonic-clonic seizures or a combination of these. Twenty-two patients completed the study. There was a significant reduction in frequency of both tonic-clonic and absence seizure types with LTG. A 350% decrease in seizures was observed for tonic-clonic seizures in 50% of cases and for absence seizures in 33% of evaluable cases. Rash was the only adverse effect causing discontinuation. Twenty-three of 26 opted for open-label LTG, with 20 still receiving LTG for a mean of 26 months. In these 20, 80% had > or =50% seizure reduction and five (25%) were seizure free. CONCLUSIONS: This study shows that LTG is effective add-on therapy in patients with refractory generalised epilepsies. Statistically significant reduction in seizures in both absence and tonic-clonic seizure types was seen even with low doses of LTG.  相似文献   
6.
Pure titanium nitride (TiN) was synthesized by mechanical alloying (MA). In order to prevent the contamination from the MA vial and atmospheric gas, the MA steel vial was replaced with a titanium vial and atmospheric gas was deoxidized using sponge titanium heated to 623 K. The mechanochemical activity during MA was estimated from the gas purification temperature. The investigation of thermal and pressure stability by thermal treatment and hot isostatic pressing (HIP) revealed that titanium nitride, TiN, was stable on heating to 1173 K under a vacuum, but became unstable under a high pressure, 100 MPa.  相似文献   
7.
PURPOSE: Stress is often noted by patients to be a precipitating factor in causing seizures. No precise data are, however, available. In 1995 for 250,000 inhabitants in The Netherlands, a serious life event occurred within a period of seven days. An extreme high water level in the province of Gelderland, with the possibility of a flood, made the government decide to evacuate people and their livestock. This retrospective study investigated the influence of this forced evacuation on the seizure frequency of patients with epilepsy, compared with patients of the same age and type of epilepsy living outside the evacuation area at the time of the threatening flood. METHODS: Information regarding epilepsy syndrome, seizure type, and frequency was derived from seizure diaries and medical histories of 30 evacuated patients and 30 matched control patients. RESULTS: Of the 30 evacuees, eight showed an increase and one a decrease in seizure frequency during or shortly after the evacuation period, compared with one and zero control patients, respectively. These results proved to be statistically significant (p < 0.05). CONCLUSIONS: Our data support the hypothesis that there is a relation, albeit small, between a stressful life event and seizure frequency.  相似文献   
8.
9.
This paper describes an optimum structural design of a CFRP isogrid cylindrical shell using a genetic algorithm (GA). When the CFRP isogrid cylindrical shell receives a prescribed uniaxial compressive load, an objective is to minimize weight of the CFRP isogrid cylindrical shell subjected to the constraint conditions of no buckling and no material failure. The buckling and material failure loads were approximated by a response surface method combined with partitioning of design spaces and these approximated values were used in the process of GA instead of FEM calculations in order to reduce the computational time. Furthermore, the differences from the constraint conditions of the linear or the non-linear (local) buckling loads were also calculated and their results were compared with each other.  相似文献   
10.
The demulsification of oil-in-water (O/W) emulsions under freezing conditions is connected to fat crystallization in the oil droplet. Therefore, demulsification can be prevented by the use of oil with a low melting point, and also by lowering the O/W ratio. However, an oil with a low melting point, such as sunflower, is rather expensive, and the O/W ratio has a significant effect on the texture of emulsions. We searched for an oil that is suitable for the production of a freeze-stable emulsion and found that soybean oil has unique characteristics. Normally, emulsions are more unstable at lower temperatures; soybean oil emulsion is unstable at −10°C and stable at −20°C. This unique characteristic results from the following two reasons. First, the solid fat content of soybean oil is almost the same at −10 and −20°C. Second, small crystals form a larger network over a period of time, and the higher temperature promotes faster restructuring. This structure formation was microscopically observed with the use of a thermostated stage. Structure formation was suppressed with the addition of a crystal structure modifier, polyglycerol fatty acid full ester, which also suppressed coalescence.  相似文献   
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