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To achieve an effective deconstruction for preparation of xylooligosaccharides (XOS) and lignin nanoparticles (LNPs) from Eucommia ulmoides, a synergistic pretreatment was successfully developed. Herein, the hemicelluloses were preferentially dissociated in acetic acid-catalyzed hydrothermal pretreatment (HTP) for preparation of XOS, and the hydrothermally-pretreated substrate was then subjected to deep eutectic solvents (DES) delignification for fabrication of LNPs. Results showed that the optimal yield (33.88% based on xylan) of XOS is obtained under the given HTP condition (170 °C, 0.5 h). NMR characterization showed that the linkages of lignin were mainly composed of β-O-4, β-β, β-5, etc. Besides, GPC analysis showed that the molecular weight of DES lignin fractions was lower (1130-1200 g/mol) than those of corresponding parent lignin fractions (8500-9620 g/mol). Further TEM characterization indicated that the optimal LNPs fraction has a narrow size distribution and the corresponding size is ranged from 60 to 110 nm. In short, the synergistic pretreatment could be used as a green and cost-effective approach for the development of bio-based chemicals and biomaterials from Eucommia ulmoides biomass.

To compare therapeutic effects of internal fixation with volar locking plate in treating extension and flexion type of distal radius fracture (DRF).From January 2015 to June 2018, 103 patients with DRF were retrospectively analyzed. According to original fracture displacement direction, patients were divided into extension fracture(Colles) group and flexion fracture (Smith) group. In Colles fracture group, there were 24 males and 44 females aged from 20 to 79 years old with an average of (59.0±13.4) years old;according to AO classification, 9 patients of type A2, 13 patients of type A3, 16 patientsof type C1, 17 patients of type C2 and 13 patients of type C3;the time from injury to operation ranged from 2 to 9 days with an average of (3.9±0.8) days. In Smith fracture group, there were 15 males and 20 females, aged from 27 to 87 years old with an average of (60.1±15.3) years old;according to AO classification, 4 patienst of A2, 7 patients of A3, 14 patients of C1, 5 patients of C2 and 5 patients of C3;the time from injury to operation ranged from 2 to 6 days with an average of (4.1±0.9) days. Operation time, fracture healing time and postoperative complications were recorded between two groups. Disabilities of arm, shoulder and hand (DASH) score at 6 and 8 weeks, 6 and 8 months were used to evaluate functional recovery of affected limbs during each follow up. Volar tilt, radial inclination and radius height were measured at 8 months after operation. Mayo score was measured at 8 months after operation to evaluate recovery of limb function.All patients were followed up for 8 to 30 months with an average of (14.8±4.3) months, and no difference in follow up between two groups (Patients with Colles fracture and Smith fracture could receive good reduction and fixation through volar locking plate. The radiographic parameters of both groups recovered satisfactorily after operation. Recovery of volar tilt of Smith fracture group is better than that of Colles fracture group, and early recovery function of Colles fracture group is better than that of Smith group, but there is no significant difference in long-term wrist joint function and incidence of postoperative complications between two groups.

The front dynamics driven by a convection field in a model of FitzHugh—Nagumo type is studied both analytically and numerically. Saddle-node bifurcation induced by the convection field is found by using a singular perturbation analysis of front solutions. Convection field accelerates the Bloch front propagating opposite the direction of convection field, but inhibits the Bloch front propagating along the direction of convection field. In addition convection field drives Ising front to travel opposite the direction of convection field.

In this paper, a reasonable model under the thermal void effect of the Insulate Gate Bipolar Transistor is been built. Finite element analysis (FE) is introduced to analyze thermal characteristics of the model. The results indicate that the heat distribution of IGBT is determined of voids with different sizes, positions and the intensity. Besides, the synergy of void effect and heat coupling effect would significantly increase the temperature of the chip.

The precursor powder of lead-zirconate-titanate (PZT) and NiFe2O4 (NFO) was prepared using one step sol-gel method. The dry powders got after a series of processes were sintered via a conventional ceramic solid-state reaction technique. All the diffraction peaks in the XRD patterns of the composites can be readily indexed to NFO and PZT, respectively. The SEM micrograph shows two different phases of PZT and NFO distinctly and the particle size of NFO was about 2~4 μm. The magnetoelectric (ME) coefficient, dielectric constant, piezoelectric constant, magnetic hysteresis loops of the samples were measured. The dc magnetic Hdc resulting in the maximum ME coefficient varies from 0.65kOe to 1.0kOe with the increase of the NFO volume fraction. The maximum magnetoelectric coefficient of 6.15Vcm-1Oe-1 was obtained at resonance frequency of 289.8kHz, dc magnetic intensity of 0.8kOe and NFO volume fraction of 0.25.

To improve cell retention on the graft with dual cell seeding technique, adding a layer of smooth muscle cells (SMCs) between the graft and endothelial cells (ECs).Polytetrafluoroethylene (PTFE) grafts pretreated with fibronectin were seeded with SMC followed by ECs one day later and exposure to an in vitro flow system. The number of ECs on grafts was counted under microscope.After exposure to the flow for 1 hour, 61% of the ECs lost when the ECs were seeded alone, whereas only 27% of the ECs lost when the ECs were seeded on the top of SMCs. Preconditioning of a cell seeded graft in a low rate flow did not improve cell retention when late exposure to a higher rate flow.This in vitro study indicates that using SMCs as a media layer between ECs and graft surface can improve the retention of seeded ECs on PTFE graft.