Breakup of spherical vesicles caused by spontaneous curvature change

We present our theoretical analysis and coarsegrained molecular dynamics (CGMD) simulation results to describe the mechanics of breakup of spherical vesicles driven by changes in spontaneous curvature. Systematic CGMD simulations reveal the phase diagrams for the breakup and show richness in breakup morphologies. A theoretical model based on Griffith fracture mechanics is developed and used to predict the breakup condition

Signal Processing for Nondifferentiable Data Defined on Cantor Sets: A Local Fractional Fourier Series Approach

From the signal processing point of view, the nondifferentiable data defined on the Cantor sets are investigated in this paper. The local fractional Fourier series is used to process the signals, which are the local fractional continuous functions. Our results can be observed as significant extensions of the previously known results for the Fourier series in the framework of the local fractional calculus. Some examples are given to illustrate the efficiency and implementation of the present method

Discharge coefficient calculation method of landing gear shock absorber and its influence on drop dynamics

Oleo-damping performance is a key factor affecting the landing gear buffer performance, while the flow discharge coefficient determines buffer damping force. For improving the calculation precision of discharge coefficient estimation method in aircraft design manual, a model for discharge coefficient is established based on pipeline fluid mechanics and damping orifice structure, and a numerical calculation is performed. Computational fluid dynamics (CFD) analysis is also conducted for damping orifice structure using the commercial software FLUNET. The simulation result of damping orifice discharge coefficient correlates well with the theoretical result. On this basis, landing gear drop dynamic response are calculated with the numerical analysis method using obtained discharge coefficient and compared with experimental results. Furthermore, the influences of current discharge coefficient estimation method and simulation method are analyzed and compared on the hydraulic force and the ground reaction force. The study demonstrates that the poor precision of discharge coefficient estimation method in aircraft design manual leads to more than 30 % differences between the drop dynamic estimation results and the experimental results. The method of CFD simulation or theoretical analysis can improve the calculation precision of discharge coefficient by about 17 %

N′-(3,4-Dihydroxy­benzyl­idene)acetohydrazide

In the title compound, C9H10N2O3, the Schiff base mol­ecule is approximately planar, the dihedral angle between the benzene ring and the acetohydrazide group (r.m.s. deviation = 0.034 Å) being 8.81 (7)°. An intra­molecular O—H⋯O hydrogen bond is observed. In the crystal, mol­ecules are linked into a three-dimensional network by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds

Analysis of safety and effect of reconstructing anterior and middle columns by single posterior approach in treating lumbar burst fractures

ObjectiveTo explore the safety and effect of the technique of reconstructing anterior and middle columns by posterior approach in treating lumbar burst fractures.MethodsFrom July 2005 to January 2007, 22 cases (18 males and 4 females, aged 28-57 years, 42.7 years on average) of lumbar burst fractures were treated with surgical procedures in our hospital. Based on the routine posterior approach, one of the transverse processes of the injured vertebra was incised to get access to the lateral side of the injured vetebral body. After all the displaced fracture fragments were cleared away and the spinal canal was decompressed, the titanium mesh packed with autografts was implanted from the lateral side to reconstruct the anterior and middle columns. The adjacent above and below segments of the vetebral body were fixed with transpedicular screws. The operation time, intraoperative blood loss, vertebral height, degree of kyphotic deformity and comprised spinal canal were documented.ResultsThe average operation time was 3.5 hours (ranging 2.8-5.8 hours) and the average blood loss was 820 ml (ranging 650-2 100 ml). All the cases were followed up for 17.2 months on average (ranging 12-28 months). The height of the injured vetebral body was restored from 24 % (12%45%) preoperatively to 96% (95%-99%) postoperatively (P<0.05). The natural spinal curvatures and spinal canal were restored. Three cases were involved in transient iatrogenic nerve root injury and 1 case was involved in the loosening of the connected rod of the pedicle screw system 3 months postoperatively.ConclusionsThe technique of implanting the titanium mesh by posterior approach is effective and safe enough to reconstruct the anterior and middle columns in treating lumbar burst fractures

2,3,4,6-Tetra-O-acetyl-β-d-galacto­pyrano­syl butyrate

The title compound, C18H26O11, was synthesized by a condensation reaction of 2,3,4,6-tetra-O-acetyl-α-d-galactopyranosyl bromide and butyric acid. The acet­oxy­methyl and butyrate groups are located on the same side of the pyran ring, showing the β configuration for the d-glycosyl ester; the butyl group adopts an extend conformation, the C—C—C—C torsion angle being 179.1 (7)°. In the crystal, the mol­ecules are linked by weak C—H⋯O hydrogen bonds