[en] Vertebral compression fractures (VCFs) are common complications of osteoporosis. The expansion of VCFs with a Sky Bone Expander is a new procedure which improves kyphotic deformities and decreases pain associated with VCFs. The purpose of this study was to investigate the preliminary results for the treatment of painful osteoporotic VCFs with a Sky Bone Expander. Twenty-six patients with pain-causing VCFs were treated with a Sky Bone Expander. This operation involved the percutaneous insertion of the Sky Bone Expander into a fractured vertebral body transpedicularly. Following the expansion, the Sky Bone Expander was contracted and removed, resulting in a cavity to be filled with bone cement. All fractures were analyzed for improvement in sagittal alignment. Clinical complications, pain relief and ambulation status were evaluated 1 day, 1 week, 1 month, and 3 months after the operation. Twenty-four hours after the operation, all the patients treated experienced some degree of pain relief. In addition, no postoperative neurologic complications were noted. The average operative time was 42.4 ± 15.5 min per vertebra. Moreover, an average cement volume of 3.5 mL (range, 2.5 ± 5.0 mL) was injected per vertebra. The average anterior height was 18.4 ± 5.1 mm preoperatively and 20.5 ± 5.3 mm postoperatively (p < 0.01). Furthermore, the average midline height was 15.5 ± 5.2 mm preoperatively and 18.9 ± 4.0 mm postoperatively (p < 0.01). The Cobb angle improved from 18.5 ± 8.2 degrees preoperatively to 9.2 ± 4.0 degrees postoperatively (p < 0.01). The Visual Anabog Scale scores decreased from 7.7 ± 1.8 points preoperatively to 3.1 ± 2.0, 2.9 ± 1.7, 2.6 ± 1.5 and 2.9 ± 11.3 after 1 day, 1 week, 1 month and 3 months after the operation, respectively. Cement extrusion was observed in four patients without any neurologic symptoms. As a result of this study, we can postulate that the expansion of compressed vetrebra with a Sky Bone Expander is a safe and minimally invasive procedure resulting in the restoration of vertebral body height and the relief of pain associated with VCFs

[en] Nitric oxide (NO) is cooled to 1 K in a seeded Ar supersonic molecular beam. NO molecules are ionized by one-color two-photon resonant enhanced multiphoton ionization (REMPI) process to form an ultracold plasma. The density of the ionized molecules in the illuminated volume approaches to 1.5 × 10"1"3 cm"−"3. Prompt electrons, plasma electrons and intact NO"+ ions are produced during this process. Experimental results confirm that the lifetime of this ultracold plasma is longer than 18.3 μs. This is the first report of NO ultracold plasma with significant lifetime produced by one-color two-photon REMPI process

[en] Stimulated raman scattering (SRS) is an effective method for expanding the spectral range of high power lasers, especially in the regime of near IR and middle IR. We report the SRS of high pressure H_2 with a multiple-pass cell configuration. The SRS with the multiple-pass cell configuration is found to be very efficient for reduction of threshold of the first Stokes (S1). Due to the coherent SRS (CSRS) process, the multiple-pass cell configuration is more effective for reduction of the threshold for the second Stokes (S2) SRS and for increasing the conversion efficiency of S2. This contributes to the relatively low conversion efficiency of S1 for the multiple-pass cell configuration. Multiple-pass cell SRS is also found to be very effective for improving the beam quality and the stability of S1. (paper)