Search

He Zhao,1,&ast; Yan-jun Wang,1,&ast; Rui-guo Wang,2 Da Liu,3 Ya-qing Duan,4 Yang-jin Liu,1 Yu-hong Zeng,5 Qin-peng Zhao,2 Zheng-ping Zhang2 1Department of Emergency Medicine, Honghui Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, 710054, People’s Republic of China; 2Department of Spine Surgery, Honghui Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, 710054, People’s Republic of China; 3Department of Orthopaedics, General Hospital of Western Theatre Command of PLA, Chengdu, Sichuan, 610083, People’s Republic of China; 4Department of Imaging, Honghui Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, 710054, People’s Republic of China; 5Department of Osteoporosis, Honghui Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, 710054, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Zheng-ping Zhang, Department of Spine Surgery, Honghui Hospital, Xi’an Jiaotong University, No. 76 Nanguo Road, Xi’an, Shaanxi, 710054, People’s Republic of China, Tel +86 17791674069, Email hh_othem@163.comPurpose: Dual-energy X-ray absorptiometry (DXA) is commonly used for evaluation of bone mineral density before spinal surgery, but frequently leads to overestimation in degenerative spinal diseases due to osteoproliferation factors. We introduce a novel method to compare the predictive ability of Hounsfield Units (HU) and DXA methods to predict screw loosening after lumbar interbody fusion surgery in degenerative spinal diseases by measuring HU of pedicle screw trajectory on computed tomography (CT) images preoperatively.Patients and Methods: This retrospective study was conducted on patients who underwent posterior lumbar fusion surgery for degenerative diseases. CT HUs measurement was performed using medical imaging software, including the cancellous region on cross-sections of the vertebral body and three-dimensional pedicle screw trajectory. Receiver operating characteristic (ROC) curve analyses were performed for the risk of pedicle screw loosening in association with the Hounsfield scale and preoperative BMD, and the area under the curve (AUC) and the cutoff values were calculated.Results: A total of 90 patients were enrolled and were divided into loosening (n = 33, 36.7%) and non-loosening groups (n = 57, 63.3%). No significant differences in age, gender, length of fixation and preoperative BMD were found between both groups. The loosening group showed lower CT HU values in the vertebral body and screw trajectory than the non-loosening group. Screw trajectory HU (ST-HU) exhibited a higher AUC value than vertebral body HU (B-HU). The cutoff values of B-HU and ST-HU were 160 and 110 HUs, respectively.Conclusion: Three-dimensional pedicle screw trajectory HU values yields a stronger predictive value than vertebral body HU values and BMD and may provide more guidance for surgery. The risk of screw loosening is significantly increased at ST-HU < 110 or B-HU < 160 at L5 segment.Keywords: osteoporosis, degenerative spinal disease, fixation failure, imaging observation

Background and Purpose: Predicting motor outcome in patients with hemorrhagic stroke due to hypertension can be a challenging task. Purpose of this research is to seek outwhether usingcombination of clinical evaluation (using Brunnstrom scale, functional walking scale and modified Rankin Scale) and DTI-based assessment of coricospinal tract damage caused by hemorrhagic stroke can be promising or not to predict motor outcome in patients with hemorrhagic stroke in basal ganglia caused by hypertension. DTI was performed at 12 hours of symptoms onset after hemorrhagic stroke in basal ganglia to predict motor outcome at 3 months. Materials and Methods: In this study, 45 patients with hemorrhagic stroke in the basal ganglia caused by hypertension admitted in Qinghai University Affiliated Hospital from August 2019 to September 2019 were enrolled. Selected patients were diagnosed with hemorrhagic stroke by head CT scan. DTI was performed at 12 hours of symptom onset in selected patients with motor deficits secondary to hemorrhagic stroke. The evaluation index was based on Brunnstrom scale, functional walking scale and modified Rankin Scale to predict motor outcome clinically. Patients were divided into 4 groups based on the level of damage to CST. Subsequently, the assessment of hemorrhage in basal ganglia, perihematomal edema (edema location and volume) and corticospinal tract involvement was done. Corticospinal tract ratios for mean diffusivity and fractional anisotropy were also calculated. Results: In this study we found that for patients with hemorrhagic stroke in the basal ganglia caused by hypertension, the DTI can be used as an effective technique to predict the prognosis of motor function, as it is capable to evaluate the damage to CST. Furthermore, it can also be used as a guide to select a suitable plan for an effective physiotherapy for such patients. Conclusions: Combination of clinical evaluation of motor function and DTI-based assessment of damage to CST from hemorrhagic stroke in basal ganglia caused by hypertension, can accurately predict motor outcome. Keywords: DTI , Hemorrhagic Stroke, Motor Outcome Prediction, Basal Ganglia, corticospinal tract, Hypertension Abbreviations: DTI_diffusion tensor imaging; CST _ corticospinal tract; FA _ fractional anisotropy; ICH _ intracerebral hemorrhage; PHE _ perihematomal edema; rFA _ FA ratio ; HICH_Hypertensive intracerebral hemorrhage;PLIC_Posterior limb of internal capsule

In this work, density functional theory method with the ωB97XD/def2-TZVP level is carried out to investigate the ground state structures, energy, electronic structures, aromaticity, infrared and Raman spectra of cyclo[18]carbon under different external electric field in the x, y and z direction of cyclo[18]carbon molecule. The excitation properties (the first 48 excited states containing excited energies, excited wavelengths and oscillator strengths) of cyclo[18]carbon are calculated by the time-dependent density functional theory method (TD-ωB97XD) with the def2-TZVP basis set under the same external electric field. The results show that cyclo[18]carbon can be elongated in the x or y direction under the electric field, and some C-C bond lengths can be elongated or shortened under the electric field. Meanwhile, the calculated results show that electric dipole moment is proved to be increasing with the increase of the external field intensity, but the total energy and LUMO-HOMO gap are proved to decrease with the increase of external field intensity. Moreover, addition of electric field can modify the electron delocalization and molecular aromaticity, such as external electric field in z direction can lower the electron delocalization and molecular aromaticity and external electric field in x or y direction can enhance the electron delocalization and molecular aromaticity. The addition of electric field can modify the infrared spectra, such as shift of vibrational frequencies and strengthening of infrared peaks. Furthermore, the calculated results indicate that the external electric field has significant effects on the excitation properties of cyclo[18]carbon. The increase of the electric field intensity can lead to the redshift of transition wavelengths (such as the first excited state). With the change of the electric field intensity, the stronger excited state (with the bigger oscillator strength) can become weak (with the small oscillator strength) or optically inactive (with the oscillator strength of zero). Meanwhile, the weak or optically inactive excited state can become stronger excited state by the external field. The ground state properties and excitation properties of cyclo[18]carbon can be modified by the external electric field. Our works can provide theoretical guidance for the application of cyclo[18]carbon in the nanotechnology such as molecular device.

In order to research the sensing characteristics of polymer optical waveguide. In this paper, the theoretical model of transmission of three-layer polymer planar optical waveguide was established based on coupled-mode theory. The working principle of optical waveguide biosensor was investigated. The article also researched the relationship between an optical guide’s physical parameters and surface sensitivity and improved on the sensitivity calculation method of composite optical guide sensing components. This paper then goes on to establish a sensitivity analysis method for disappeared wave type sensing components. Based on this, the article has developed sensitivity calculation software for high sensitivity optical guide sensing components and improved film refraction rate of the method for sensitivity calculation.

The recent discovery of borospherene B40 marks the onset of a new class of all-boron fullerenes. External electric field can influence the structure and property of molecule. It is necessary to understand the electrostatic field effect in the borospherene B40. In this work, density functional theory method at the PBE0 level with the 6-31G* basis set is used to investigate the ground state structures, mulliken atomic charges, the highest occupied molecular orbital (HOMO) energy levels, the lowest unoccupied molecular orbital (LUMO) energy levels, energy gaps, electric dipole moments, infrared spectra and Raman spectra of borospherene B40 under the external electric field within the range of values F=0-0.06 a.u.. The electronic spectra (the first 18 excited states contain excited energies, excited wavelengths and oscillator strengths) of borospherene B40 are calculated by the time-dependent density functional theory method (TD-PBE0) with the 6-31G* basis set under the same external electric field. The results show that borospherene B40 can be elongated in the direction of electric field and B40 molecule is polarized under the external electric field. Meanwhile, the addition of external electric field results in lower symmetry (C2v), however, electronic state of borospherene B40 is not changed under the external electric field. Moreover, the calculated results show that the electric dipole moment is proved to be increasing with the increase of the external field intensity, but the total energy and energy gap are proved to decrease with the increase of external field intensity. The addition of external electric field can modify the infrared and Raman spectra, such as the shift of vibrational frequency and the strengthening of infrared and Raman peaks. Furthermore, the calculated results indicate that the external electric field has a significant effect on the electronic spectrum of borospherene B40. The increase of the electric field intensity can lead to the redshift of electronic spectrum. With the change of the electric field intensity, the strongest excited state (with the biggest oscillator strength) can become very weak (with the small oscillator strength) or optically inactive (with the oscillator strength of zero). Meanwhile, the weak excited state can become the strongest excited state by the external field. The ground state properties and spectral properties of borospherene B40 can be modified by the external electric field. Our findings can provide theoretical guidance for the application of borospherene B40 in the future.

The unique electromagnetic properties of left-handed materials have received much attention due to their applications in microwave devices, radar antenna and electromagnetic stealth and so on. However, the double side etching of dielectric substrate for most traditional left-handed materials will lead to the complexity of manufacture, narrow left-handed bandwidth and higher loss. In order to overcome the shortages of traditional left-handed materials, a new broadband and low-loss left-handed material with multi-opening cross shape structure is presented in this paper. The structure is fabricated on a single side of a dielectric substrate by integrating an electric resonator with a magnetic resonator to form a left-handed unit. Through theoretical analysis, software simulation and effective electromagnetic parameters extraction, the results show that the structure has a double negative characteristics (ε μ

This paper analyzes the design features of subordinated debt issued by Chinese banks during 2003-2010, and shows their impacts on market discipline effect based on the comparison with the features of subordinated debt issued by American banks, and then from the view of market discipline summarizes the main problems in Chinese market of subordinated debt, finally gives some suggestions on improving the market discipline effect of subordinated debt in Chinese banks.

For transmission of multimedia over 3G wireless networks, H.264/AVC represents a major step forward in the development of video coding standards. In this paper, firstly, the authors briefly introduce a overview of H.264/AVC standard and propose the related coding tools, usingDM6446. Then, the paper gives the hardware and software design of a simulation system, this system can acquire the multimedia information and send the information by 3G interface. At the last section, the authors compare the H.264/AVC standard with other prior coding standards. The results show that H.264/AVC standard will enable new applications and business opportunities to be developed.

Since May 2008, the experiments of the commercial micro-credit companies (MCCs) in China which permitted to offer loans but not to take deposits have been expanded to the whole country fast, and the development of MCCs has received more attention. However, a new policy on the MCCs issued by the CBRC (China Banking Regulation Commission) in June 18, 2009 caused extensive disputes. This paper first summarizes the relevant policies and its development, and then focuses on analyzing the transformation rules of the MCCs to village banks and its main disputes, and then makes a deep reflection on the transformation rules of MCCs and its potential developing directions in the future.

The Hartree-Fork (HF) method with LANL2DZ basis set is used to investigate the equilibrium structures, atomic charge distributions, the highest occupied molecular orbital (HOMO) energy levels, the lowest unoccupied molecular orbital (LUMO) energy levels, energy gaps, dipole moments, harmonic frequencies and infrared intensities of ZnSe under different external electric fields ranging from -0.025 to 0.040 a.u. The excitation energies, transition wavelengths and oscillator strengths under the same external electric fields are calculated by the time-dependent-HF method. The results show that the bond length and electric dipole moment are proved to be first decreasing, and then increasing with the variation of the external field; the total energy is found to decrease linearly with the variation of external field; but the HOMO energy and energy gap are proved to increase with the variation of external field. The harmonic frequency and LUMO energy are found to first increase, and then decrease, but the infrared intensities are proved to first decrease, and then increase. The external electric field has significant effect on the excitation properties of ZnSe molecule. The excited energies from ground state to the first nine excited states are found to increase, and the transition wavelengths are decreasing with the variation of the external field. Meanwhile, the strongest excited state becomes very weak, and the weak excited state becomes strongest by the external field. The excitation properties of ZnSe material can be changed with external electric field.