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Background To evaluate the difference in root resorption between standard torque self-ligating brackets and high torque self-ligating brackets in bimaxillary protrusion patients after orthodontic treatment. Methods Pre-treatment and post-treatment Cone beam computed tomography (CBCT) of 32 patients (16 treated with the high torque DamonQ 0.022″ bracket and 16 with the 0.022″ standard torque self-ligating bracket) were selected. The first premolars were extracted from all patients before treatment. After mini-screw implants were inserted into the buccal region between the second premolar and first molar, 150 g of force was applied to retract the upper and lower anterior teeth to close the extraction space on each side. CBCT images of all patients were taken before and after treatment. Three-dimensional reconstruction of the maxillary central incisor, lateral incisor and canine was conducted with Mimics 20.0 software. The volumes of the roots were calculated using Gomagics Studio 12.0 software. The differences between the pre-treatment and post-treatment root volumes were statistically evaluated with a paired-samples t-test. Results There was no statistically significant difference in root resorption degree between the two kinds of torque brackets. The patient’s degree of root resorption in the high torque self-ligating group was greater than that in the standard torque group. Conclusions There was no significant difference in root external apical resorption between the high torque self-ligating brackets and the standard torque self-ligating brackets in bimaxillary protrusion patients.

Here we reported a compact plasmonic filter design based on the block-loaded rectangular ring cavity. The selected wavelength can be flexible modulated to longer ones without extending the filter dimension. Such filter was composed of a common rectangular ring and several loaded nanoblocks. This is attributed to the electrical field perturbation caused by the loaded block. The resonant mode was found sensitive to the nanoblock which located at the antinode position, and the proportional relationship was revealed between the selected wavelength and the nanoblock size and number, which ensured the accurate determination of the selected wavelength. In particularly, this proposed plasmonic filter possess a more compact size than the common used one for the same properties. These findings can be beneficial for the integrated optical circuit design and may improve the integration level.

Cultural values are giving increased attention in natural resource management policy and practice, particularly in relation to water resources. Water culture has spatial characteristics, such as space-time difference, scale, and carrier. This study developed a comprehensive framework to incorporate Chinese traditional water culture concepts into the water space planning and design process. Specifically, a systematic strategic framework for the protection and integration of the historical urban water environment is constructed from macro-, medium-, and micro-levels, to strengthen the security pattern of water ecosystems, maintain urban water environment features, and protect the natural processes of water. Finally, a typical Chinese historical town is selected as a research object, and a series of specific measures are put forward to promote the sustainable development of its ecological culture. From the perspective of water culture, it is not only the integration of water space, but also the integration of concept, social, environment, ecology, economic, and other contents with space as the carrier.

The objective is to compare the intraoperative monitoring (IOM) outcomes between degenerative cervical and thoracic spine decompression surgery. A total of 97 patients with cervical compression myelopathy (CCM) and 75 patients with thoracic compression myelopathy (TCM) were prospectively collected between December 2012 and June 2015 in our spine center. Somatosensory-evoked potentials (SSEP) and motor-evoked potentials (MEP) were used for IOM. The postoperative neurologic status of each patient was assessed immediately after surgery. And the IOM and neurological outcomes were mainly analyzed in this study. Under the same alarm criteria, the IOM changes present significant difference between the cervical and thoracic surgery. During the patients with monitoring alerts, the MEPs usually manifest as sudden loss in TCM whereas the gradual loss in CCM. And there were three permanent neurologic injuries in the thoracic cases, but none in cervical cases. The IOM loss between CCM and TCM patients present obvious difference and the sudden MEPs loss associated with spinal decompression need to be taken seriously especially in TCM.

High-pressure processing at mild temperatures (HPMTs) could be an alternative to thermal processing for destroying pressure-resistant bacteria and achieving commercial sterilization. In this study, carrot juice was pressure-treated at 300, 400 and 500 MPa for 15 min at 40, 50 and 60C, and afterward stored at 4, 25 and 37C. The results showed that 400–500 MPa/50C and 300–500 MPa/60C-treated samples had a shelf life of 28 days at 4C, lasting just as long as heat-treated samples. HPMT reduced peroxidase activity to 16–50%. The vitamin C content of the HPMT-treated samples was 28.7–60.7% higher than that of the heat-treated samples. HPMT conditions, except 500 MPa/60C, preserved lightness (L*) and redness (a*) better than heat treatment (P

A theoretical investigation of the pulse trapping in a highly birefringent photonic crystal fiber was presented.The strict coupled nonlinear Schrdinger equations were numerically solved using a split-step Fourier algorithm.Different incidence conditions were discussed when the two pulses were polarized along the same polarization axes.The pump pulse in abnormal dispersion regime traped the signal pulse in the normal dispersion regime,and the signal pulse shifted to shorter wavelength with the pump pulse of the longer wavelength in order to keep the same group velocity.Different initial temporal separation between the pump pulse and the signal pulse leaded to different effect in the pulse trapping.As the input peak power of the pump pulse was increased,the red-shift of pump pulse was considerably enhanced with the simultaneous further blue-shift if the trapped pulse to satisfy the condition of group velocity matching.Pulse trapping was inconspicuous as the full width at half maximum of the pump pulse was increased.In order to realize pulse trapping,the wavelengths of the pump and signal pulses should be near the zero dispersion point and the discrepancy between two group velocities should be small.

The generation and control mechanisms of a broadband supercontinuum(SC)in photonic crystal fibers(PCF)with two-zero dispersion wavelengths are demonstrated by simulating the evolution process of a femtosecond pulse numerically.The results reveal that the intrinsic higher-order dispersions and nonlinear effects of PCFs cause the pump pulse,whose center wavelength locates between the anomalous dispersion region,decay into fundamental solitons and two dispersive waves simultaneously.In virtue to the enhancement of the two dispersive waves by their phase-matched solitons,SC will be formed by the two dispersive waves,on which oscillations happen for the interference.Then,the limited effect on the SC applied by the two dispersive waves is analyzed quantitatively by comparing the SCs in three PCFs with different geometrical parameters.Meanwhile,the effects of the geometrical parameters are demonstrated.Based on the above conclusions,considering the analysis on the relationships between the center wavelengths of the dispersive waves and the dispersion curves of PCFs as well as their geometrical parameters,a method to control the range of SC is promoted based on the design of the geometrical parameters.As an example,a flat SC extending to the visible region is achieved by optimizing the geometrical parameter in theory.

Magnetic sensor is a key component of electronic compass used to measure the magnetic field in geomagnetic navigation. The development of high-precision three-axis vector magnetic sensor is the foundation and core of the geomagnetic navigation. To improve the accuracy of measurement, on the basis of analyzing the sensor working principle and error sources, several error models are established and the compensation algorithms are developed. Through comparison of three kinds of most commonly used compensation algorithms, including twenty four attitude algorithm, ellipsoid fitting algorithm and FLAAN algorithm, it is found that the ellipsoid fitting method is more effective and can analyze the advantages and disadvantages of each compensation method.

Risk management is usually neglected in the management of IT software project. But the quality of risk management plays important role in the fulfillment of IT software project. This article mainly researches on the theories and methods of risk management identification, risk assessment, risk management tactics and risk control.

It is obvious that informal organization widely exists in social organizations, and informal organization lies in any organization, and it comes along with formal organizations. Once an informal organization appeared, it will penetrate with formal organization, and work on the activities formal organization in every aspect, especially in human resources management. The emergence of informal organization, internal rules and influences determine that it must be held by right attitude to bring the positive role of informal organization into full play in the process of management. Through analyzing the emergence and fundamental meaning, as well as the main features of informal organization, this paper presents both positive and negative effects of informal organizations on formal organizations, and then proposes responding strategies to informal organization and provides a theoretical basis and practical approach to the management of informal organization.

This paper introduces an auto-discharging system for jigging machine based on switched reluctance motor (SRM). In this system, SRM is used to replace the traditional asynchronous motor. The hardware system, controller and software design methods are discussed in this paper. AT89C51 is taken as the core component of the speed regulation controller for SMR and works with other peripheral circuits to realize effective control on motor. The experiment shows that auto-discharging system for jigging machine based on SRM is feasible and can play an important role in stabilizing clean coal ash content, reducing clean coal loss, improving product quality and separation efficiency.

Laser speckles produced from living objects is called 'bio-speckles'. Bio-speckles observed from the human skin contains information about blood flow in dermal capillarities, heartbeat, and other physiological activity. The time sequence of bio-speckles is a kind of complex fluctuation and has a certain degree of briskness. The thickness of skin will influence the briskness of bio-speckles.

Objective Cytochrome P450 2E1 (CYP2E1) is an effective generator of reactive oxygen species, such as the superoxide anion radical and hydrogen peroxide. The expression of CYP2E1 varies with the progression of myocardial ischaemia and cardiomyopathy. This paper examined the heart specific CYP2E1 transgenic mice to study the effect of CYP2E1 on DCM. Methods The expression of CYP2E1 in both hypertrophic cardiomyopathy (HCM) and DCM mice were analysed using RT-PCR and western blot on cTnTR92Q and cTnTR141W transgenic mice. The cDNA of CYP2E1 was amplified by RT-PCR from the mice heart, and del inserted into the downstream of α-MHC promoter to construct the CYP2E1 expression vector. The transgenic mice were created by the method of microinjection. And they were del crossed with cTnTR141W transgenic mice. The cardiac structure and function were analysed with M-mode echocardiography. Survival data of the experimental mice were recorded. Pathologic changes were observed by light microscopy. The contents of hydrogen peroxide (H2O2), malonaldehyde malondialdehyde (MDA), reduced glutathione (GSH) as well as the total anti oxidation capable (T-AOC) were detected by spectrophotometry. Myocyte apoptosis was analysed by in situ terminal dUTP nick end-labelling (TUNEL) stain. Results In the current paper, it was indicated that expression of CYP2E1 was lightly up-regulated in HCM hearts from cTnTR92Q transgenic mice and was strongly down-regulated in DCM hearts from cTnTR141W transgenic mice at 3 months old. The transgenic expression of CYP2E1 reduced mortality of CYP2E1 transgenic mice by 7.5% and increased the mortality of cTnTR141W transgenic mice from 10% to 45% (n=40, p Conclusions Expression of CYP2E1 was regulated in the progression of transgenic cardiomyopathy mice. CYP2E1-mediated oxidative stress and myocyte apoptosis may play an important role in aggravating the DCM phenotype.