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The dynamic characteristics of long-span suspension bridges are complex. The natural vibration frequency is changed with different structural parameters, and the sensitivity to different parameters is different. In order to solve this problem, the spatial model of a long-span suspension bridge was established by using finite element software, and the first 20 natural vibration periods, natural vibration frequencies and vibration modes were analyzed and calculated. The accuracy of the obtained natural vibration frequency data was verified through field tests. Finally, based on the model, the stiffness of structural components is studied by one -factor-at-one-time, and the influence of various variables on the frequency and mode of a certain mode is studied by one-factor-at-one-time method. The results show that different structural parameters have different effects on the vibration frequency. When the stiffness of stiffening girder and main tower is changed, with the increase of stiffness, the variation of frequency mostly presents an upward trend, and the range is large. With the change of the secondary dead load, most of the frequencies decrease first and then tend to be stable. It can be seen from the field test results that the vibration shapes and frequencies measured by numerical simulation and test are close to each other, which can meet the requirements of engineering precision. The stiffness of the main cable and the main tower has a great influence on the modes and periods corresponding to them. The increase of the secondary dead load can reduce the natural vibration frequency of the suspension bridge, but it is not unlimited to increase the secondary dead load to reduce the frequency. The stiffness of the stiffening girder has a great influence on the frequency of the suspension bridge. When the bending stiffness of the stiffening girder increases to 3 times of the original one, the order of vibration modes of the structure will change. The research results can provide references for structural design and dynamic parameter adjustment of long-span suspension bridge.

This study developed a novel error compensation method aimed at eliminating placement error caused by hand–eye calibration and pick-and-place tool motions in automatic stiffener bonder for flexible printed circuit. Using the transformation of homogeneous coordinates to develop an error model of the system describing the coupling of errors among various coordinate systems, the least squares method is used to calculate the unknown model parameters. The experiment results demonstrate that this error compensation method reduced placement error by an order of magnitude. The mounting precision throughout the entire work area was ±0.046 mm at 3sigma, and for flexible printed circuit products with a specification limit of 0.1 mm, the process capability index of the automatic stiffener bonder in this study was 2.19. This represents that the system is capable of fully satisfying the precision requirements of flexible printed circuit stiffener bonding. The proposed system employing a vibrating feeder bowl and machine vision–aided target positioning is applicable to a variety of stiffeners, which enhances production flexibility. The proposed error model considers the complex coupling effect of the errors among multiple coordinate systems in hand–eye calibration, without the need of detecting and calculating the calibration error item by item, and takes into account the errors produced by the rotation and downward pressing motions of the pick-and-place tool.

In remote sensing, conventional supervised change-detection methods usually require effective training data for multiple change types. This paper introduces a more flexible and efficient procedure that seeks to identify only the changes that users are interested in, here after referred to as “targeted change detection”. Based on a one-class classifier “Support Vector Domain Description (SVDD)”, a novel algorithm named “Three-layer SVDD Fusion (TLSF)” is developed specially for targeted change detection. The proposed algorithm combines one-class classification generated from change vector maps, as well as before- and after-change images in order to get a more reliable detecting result. In addition, this paper introduces a detailed workflow for implementing this algorithm. This workflow has been applied to two case studies with different practical monitoring objectives: urban expansion and forest fire assessment. The experiment results of these two case studies show that the overall accuracy of our proposed algorithm is superior (Kappa statistics are 86.3% and 87.8% for Case 1 and 2, respectively), compared to applying SVDD to change vector analysis and post-classification comparison.

The dynamic motions of protein structural elements, particularly flexible loops, are intimately linked with diverse aspects of enzyme catalysis. Engineering of these loop regions can alter protein stability, substrate binding and even dramatically impact enzyme function. When these flexible regions are unresolvable structurally, computational reconstruction in combination with large-scale molecular dynamics simulations can be used to guide the engineering strategy. Here we present a collaborative approach that consists of both experiment and computation and led to the discovery of a single mutation in the F/G loop of the nitrating cytochrome P450 TxtE that simultaneously controls loop dynamics and completely shifts the enzyme's regioselectivity from the C4 to the C5 position of L-tryptophan. Furthermore, we find that this loop mutation is naturally present in a subset of homologous nitrating P450s and confirm that these uncharacterized enzymes exclusively produce 5-nitro-L-tryptophan, a previously unknown biosynthetic intermediate.

With the rapid development of information technology in power grid enterprises, there are many information systems in relevant business departments. It is difficult to avoid the dilemma of duplication of business functions and waste of data resources because of the “chimney” function development model oriented to business lines. Aiming at the decentralized management status of data related to blackout business such as smart grid dispatching technology support system, production management system, distribution automation system and marketing system, based on the system architecture of business center, this paper takes integrated blackout intelligent optimization as the construction goal, and optimizes blackout inspection from the standardisation of data. Repair plan, improve the coordination efficiency of relevant business departments, avoid repeated blackouts, improve the reliability of power supply, and provide decision support for power grid enterprises in blackout management.

Unsupervised change detection techniques have been widely employed in the remote-sensing area when suitable reference data is not available. Image (or Index) differencing is one of the most commonly used methods due to its simplicity. However, past applications of image differencing were often inefficient in separating real change and noise due to the lack of steps for feature selection and integration of contextual information. To address these issues, we propose a novel unsupervised procedure which uses two complementary features, namely luminance and saturation, extracted from multispectral images, and combines T-point thresholding, Bayes fusion, and Markov Random Fields. Through a case study, the performance of our proposed procedure was compared with other three unsupervised change-detection methods including Principle Component Analysis (PCA), Fuzzy c-means (FCM), and Expectation Maximum-Markov Random Field (EM-MRF). The change detection results from our proposed method are more compact with less noise than those from other methods over urban areas. The quantitative accuracy assessment indicates that the overall accuracy and Kappa statistic of our proposed procedure are 95.1 percent and 83.3 percent, respectively, which are significantly higher than the other three unsupervised change detection methods.

Background: Patients with rheumatoid arthritis (RA) are predisposed to osteoporotic fracture. The present study aims to determine the association between rheumatoid arthritis (RA) and bone fracture risk, and in relation to gender and site-specific fractures. Methods: Studies related to bone fracture in patients with RA were searched from databases including PubMed, EMBASE, and OVID from inception through April 2016. The quality of the studies was evaluated using the Newcastle-Ottawa Scale. Meta-analysis was performed with Stata13.1 software. The results were reported based on risk ratio (RR) and 95% confidence interval (95% CI) using a random effects model. Results: The meta-analysis of 13 studies showed a significant higher risk of bone fracture in patients with RA than in patients without RA (RR = 2.25, 95% CI [1.76–2.87]). Subgroup analyses showed that both female and male patients with RA had increased risk of fracture when compared with female and male patients without RA (female: RR = 1.99, 95% CI [1.58–2.50]; male: RR = 1.87, 95% CI [1.48–2.37]). Another subgroup analysis of site-specific fracture also showed that RA is positively correlated with the incidence of vertebral fracture (RR = 2.93, 95% CI [2.25–3.83]) or hip fracture (RR = 2.41, 95% CI [1.83–3.17]). Conclusion: RA is a risk factor for bone fracture in both men and women, with comparable risks of fractures at the vertebral and hip.

To discuss the application of convoluted manipulation in pediatric femoral fractures.From March 2015 to October 2016, 12 children with femoral fractures were treated by Chinese traditional manipulation including 8 males and 4 females with an average age of 6 years old ranging from 1 to 12 years old. The causes of injury were falls in 10 cases and traffic accidents in 2 cases. Of which 1 case was transverse fractures, 4 cases were oblique fractures and 4 cases were spiral fractures, 2 cases were comminuted fracture, 1 case was greenstick fracture. All patients underwent manual reduction within 1 to 2 days, plus small splint with cedar bark, and parallel lower limb traction.All the 12 patients were followed up for 1-3 months, with an average of 2 months. All the 12 patients achieved clinical union, and the average healing time was 6 weeks. There was no obvious shortening and rotational angulation. At the last follow-up, Schatzker-Lambert distal femoral fracture evaluation results were excellent in 11 cases, good in 1 case.Convoluted manipulation is very important for reduction of femoral fractures in children, with the splint of cedar bark, satisfactory therapeutic effect can be achieved.

Autism spectrum disorders (ASDs) is a set of complex neurodevelopment disorders that is prevalent in children and is increasing at a steady rate in recent years. However, the etiology of autism is still poorly understood. Humans are at higher risk of chemical exposure than in the past as a result of the increasing usage of chemicals in various fields, including food preservation, agriculture, industrial production, etc. A number of environmental agents have been suggested as contributing factors to ASD pathogenesis, which includes heavy metals (Hg and Pb), persistent organic pollutants (DDT, PBDEs and PCBs) and emerging chemicals of concern (phthalates and BPA). These three main categories of toxicants could be the cause of ASD in children. Recent research into the causes of ASD that have been linked to environment factors are reviewed in this paper. There are evidence supporting the etiological link between exposure to environmental toxicants and the development of ASD. Children exposed to these toxicants in the environment exhibit signature traits of ASD and have been reported with high body burdens of these chemicals and/or their metabolites, which may provide an explanation for the observed relation, yet comprehensive evidence in humans is limited, highlighting the need for further research.

The spectrometer is a basic tool of optical measurement, having a wide application field. Because of its small visual range and used in a dark environment, traditional spectrometer cause eye fatigue, inconvenient in reading figure and its utilization rate is low. In order to solve these problems, I utilize Xilinx FPGA and CCD to retrofit the traditional spectrometer. Making the image which in the eyepiece shown on the displayer, realize the goal of Digital Angle measurement. The new design spectrometer has the advantage of operate simply, convenient maintenance, etc.

Solid-oxide-oxygen-ion conducting membrane (SOM) process is a novel, high efficient, low cost, energy-saving, environmentally friendly electrochemical extraction method of metals or alloys. This work demonstrated the prototype development of preparation of hydrogen storage alloys by SOM process, and Ti–Fe based quaternary alloy was successfully prepared directly from the oxides in molten calcium chloride. The assembling process of electrode utilized in the recycled battery was extended to prepare the novel cathode, it proved that this design can effectively simplify the assembly process and dissolve the problem of incomplete electrolysis. It is shown that SOM electro-deoxidization process was faster and more efficient for the current, the as-prepared alloy showed a good stability in the charging/discharging cycles and the capacity reached 27.88 mAh g−1 after ten activated cycles.

Taking partially coherent cosh–Gaussian (ChG) beams as an example of more general partially coherent beams, we have studied the spectral degree of coherence of partially coherent ChG beams in the far field. It is shown that, unlike Gaussian Schell-model (GSM) beams, in the strict sense there do not exist two partially coherent ChG beams which can generate far fields with the same spectral degree of coherence. However, under certain conditions it is possible to find two partially coherent ChG beams with the same spectral degree of coherence in the far field.

KIF21A is a member of the Kinesin superfamily proteins (KIFs), which are microtubule-dependent molecular motors, anterograde axonal transporters of cargoes. Recently, congenital fibrosis of the extraocular muscles 1 (CFEOM1) has been shown to result from a small number of recurrent heterozygous missense mutations of KIF21A. CFEOM1 results from the inability of mutated KIF21A to successfully deliver cargoes to the development of the occulo-motor neuron or neuromuscular junction. Here, we used an yeast two-hybrid system to identify a protein that interacts with the WD-40 repeat domain of KIF21A and found a specific interaction with Purkinje cell protein-2 (Pcp-2), a small protein also known as L7. Pcp-2 protein bound to the WD-40 domain of KIF21A and KIF21B but not to other KIFs in yeast two-hybrid assays. In addition, this specific interaction was also observed in the glutathione S-transferase pull-down assay. An antibody to Pcp-2 specifically co-immunoprecipitated KIF21A associated with Pcp-2 from mouse brain extracts. These results suggest that Pcp-2 may be involved in the KIF21A-mediated transport as a KIF21A adaptor protein.