Suyoung Park

Treatment of intertrochanteric fracture with the Gamma AP locking nail or by a compression hip screw – a randomised prospective trial

Abstract.The Gamma AP (Asia-Pacific) locking nail (GAPN) is a modification of the standard Gamma locking nail made especially for use in Oriental patients. We made a randomised prospective comparison of the compression hip screw (CHS) and the Gamma AP locking nail for the internal fixation of 60 intertrochanteric fractures of the hip in elderly patients by comparing perioperative details and analysing the radiographic and clinical results. The operation time for the GAPN group was shorter than for the CHS group and the intraoperative blood loss was lower. The Gamma AP nail enabled earlier mobilisation. We found no significant difference in the time to union and the length of sliding of the lag screw between the two groups. The decrease in the neck shaft angle in the Gamma nail group was significantly smaller than in the CHS patients. There were no significant mechanical complications, such as fracture of the femoral shaft or failure of fixation in the Gamma nail group. On the basis of our observations we conclude that the Gamma AP locking nail is more efficient than the CHS in the treatment of intertrochanteric fractures in geriatric patients.Résumé.Le clou verrovillé Gamma AP (Asie Pacifique) est la modification du clou Gamma standard pour le morphotype Oriental. Nous avons compare au hasard la compression du col du fémur vissé au clou verrouillé Gamma AP pour la fixation de 60 fractures inter-trochantériennes du col de fémur, en comparant, les details périopératoires, en analysant la radiographie et les résultats cliniques chez des patients agés. La durèe d’opération pour le groupe GAPN était plus courte que pour le groupe CHS, et les pertes sanguines étaient plus faibles dans le groupe GAPN. Le clou Gamma AP favorise l’ambulation plus rapide. Nous n’avons trouvé aucune différence notable de temps de consolidation ni de glissement de la vis entre les deux groupes. La diminution d’angle cervico-diaphysaire dans le groupe clou Gamma était nettement moindre que celle du groupe CHS. Il n’y avait, pas de probléme mécanique grave dans le groupe clou Gamma comme la fracture de diaphyse femorale ou la fixation defailiante. Nous concluons que dans le traitement de la fracture intertrochanterienne de patients agés, le clou verrorillé Gamma AP serait plus efficace que le CHS.

Effects of functionalization of TiO2 nanotube array sensors with Pd nanoparticles on their selectivity.

This study compared the responses of Pd-functionalized and pristine titanate (TiO2) nanotube arrays to ethanol with those to acetone to determine the effects of functionalization of TiO2 nanotubes with Pd nanoparticles on the sensitivity and selectivity. The responses of pristine and Pd-functionalized TiO2 nanotube arrays to ethanol gas at 200 °C were ∼2877% and ∼21,253%, respectively. On the other hand, the responses of pristine and Pd-functionalized TiO2 nanotube arrays to acetone gas at 250 °C were ∼1636% and 8746% respectively. In the case of ethanol sensing, the response and recovery times of Pd-functionalized TiO2 nanotubes (10.2 and 7.1 s) were obviously shorter than those of pristine TiO2 nanotubes (14.3 and 8.8 s), respectively. In contrast, in the case of acetone sensing the response and recovery times of Pd-functionalized TiO2 nanotubes (42.5 and 19.7 s) were almost the same as those of pristine TiO2 nanotubes (47.2 and 17.9 s). TiO2 nanotube arrays showed the strongest response to ethanol and Pd functionalization was the most effective in improving the response of TiO2 nanotubes to ethanol among six different types of gases: ethanol, acetone, CO, H2, NH3 and NO2. The origin of the superior sensing properties of Pd-functionalized TiO2 nanotubes toward ethanol to acetone is also discussed.

Growth of nitrogen-doped p-type ZnO thin films prepared by atomic layer epitaxy

Abstract Nitrogen-doped, p-type ZnO thin films were grown successfully on sapphire (0001) substrates by using atomic layer epitaxy (ALE). Zn(C2H5)2[Diethylzinc, DEZn], H2O and NH3 were used as a zinc precursor, an oxidant and a doping source gas, respectively. The lowest electrical resistivity of the p-type ZnO films grown by ALE and annealed at 1000°C in an oxygen atmosphere for 1 h was 18.3 Ω·cm with a hole concentration of 3.71 × 1017 cm−3. Low temperature-photoluminescence analysis and time-dependent Hall measurement results support that the nitrogen-doped ZnO after annealing is a p-type semiconductor.

ENHANCED ETHANOL SENSING PERFORMANCES OF MULTIPLE NETWORKED Nb2O5 NANOROD SENSORS FUNCTIONALIZED WITH Pd AND Au NANOPARTICLES

Over the past decade, functionalization with bimetallic catalysts have been studied owing to their excellent catalytic activities for various reactions, whereas few studies have been performed on cofunctionalization with two different types of metal catalysts despite its simplicity. This study examined the sensing performances of Nb2O5 nanorods cofunctionalized with Pd and Au nanoparticles. Pd, Au-cofunctionalized Nb2O5 nanorods were prepared by a hydrothermal technique. The Nb2O5 nanorods cofunctionalized with Pd and Au nanoparticles showed far stronger response to ethanol gas than the Pd or Au-functionalized counterpart. The origin for the enhanced response of the Pd, Au-cofunctionalized Nb2O5 nanorods is discussed.

Growth Mechanism and Luminescent Properties of Amorphous SiOx Structures via Phase Equilibrium in Binary System.

Balloon whisk-like and flower-like SiOx tubes with well-dispersed Sn and joining countless SiOx loops together induce intense luminescence characteristics in substrate materials. Our synthetic technique called “direct substrate growth” is based on pre-contamination of the surroundings without the intended catalyst and source powders. The kind of supporting material and pressure of the inlet gases determine a series of differently functionalized tube loops, i.e., the number, length, thickness, and cylindrical profile. SiOx tube loops commonly twist and split to best suppress the total energy. Photoluminescence and confocal laser measurements based on quantum confinement effect of the embedded Sn nanoparticles in the SiOx tube found substantially intense emissions throughout the visible range. These new concepts related to the synthetic approach, pre-pollution, transitional morphology, and permeable nanoparticles should facilitate progress in nanoscience with regard to tuning the dimensions of micro-/nanostructure preparations and the functionalization of customized applications.

Design and synthesis of amorphous SiOx structures generated by Sn quantum dots: growth mechanism and luminescent origin.

SiOx structures with different diameters of a few hundreds of nanometers and/or a few micrometers are prepared using applied thermal evaporation. Subsequently, Sn quantum dot-based SiOx architectures are synthesized via the continuous steps of the carbothermal reduction of SnO2, substitution of Sn(4+) for In(3+), thermal oxidation of Si, Sn sublimation, interfacial reaction, and diffusion reaction consistent with corresponding phase equilibriums. Several crystalline and spherical-shaped Sn quantum dots with diameters between 2 and 7 nm are observed in the amorphous SiOx structures. The morphological evolution, including hollow Sn (or SnOx) sphere and wire-like, worm-like, tube-like, and flower-like SiOx, occurs stepwise on the Si substrate upon increasing the given process energies. The optical characteristics based on confocal measurements reveal the as-synthesized SiOx structures, irrespective of whether crystallinity is formed, which all have visible-range emissions originating from the numerous different-sized and -shaped Sn quantum dots permeating into the SiOx matrix. In addition, photoluminescence emissions ranging between ultraviolet and red regions are in agreement with confocal measurements. The origins of the morphology- and luminescence-controlled amorphous SiOx with Sn quantum dots are also discussed.