•The effects of abnormal arrivals were eliminated successfully using the analytical localization method.•The temporal and spatial errors caused by premeasured wave velocity were weakened efficiently ...with TD.•An effective collaborative localization method for MS/AE was proposed using analytical and TD methods.•The proposed CLMAI is a beneficial complement for the current localization methods of MS/AE.•The CLMAI is applicable to MS localization in the rockmass structure of dynamic underground mining.
The localization of microseismic sources/acoustic emission in the rockmass structure can provide the basis for determining the potential areas of rockmass instability and rockburst in the underground mining. As the construction environment in deep mining is complex, the abnormal arrivals with different scales of errors may be recorded by the monitoring sensors, which can lead to large errors between the located results and the authentic coordinates. In addition, the average premeasured P-wave velocity through blasting tests (blasts) is widely used in the current localization methods, which are unsuitable for the mining environment with dynamic change of wave velocity in multi-level and multi-stope. To eliminate the effects of abnormal arrivals, the analytical localization method is used to remove abnormal arrivals since it has a stable solution with the high precision when the input data are accurate. To weaken errors induced by the dynamic wave velocity, the iterative solution without the need of premeasured P-wave velocity is used to improve the locating accuracy since it can optimize results using the advantage of multiple sensors. Therefore, a collaborative localization method using analytical and iterative solutions (CLMAI) was proposed, which combined with the arrivals of multi-sensor and inversion of the real-time average wave velocity, to seek the optimal locating results. Firstly, the analytical solutions using 6 sensors in unknown velocity system were resolved. The method to remove abnormal arrivals is developed by solving the logistic probability density function for the analytical solutions of different sensors combinations. Then, the iterative localization method based on the time differences was used to locate source coordinates with clear arrivals. Finally, the CLMAI is verified through locating coordinates of blasts and microseismic events (events) in Kaiyang phosphorous mine. Results show that the CLMAI can not only filter the abnormal arrivals by making use of the characteristic of analytical solutions, but also use the iterative method without premeasured average velocity to improve the locating accuracy significantly. The proposed method is a beneficial complement for the current iterative methods using premeasured velocity, which is applicable to microseismic sources localization under complex abnormal arrivals in the rockmass structure of dynamic underground mining.
Organ protection is a routine therapy in severe injuries. Our aim was to evaluate the beneficial effects of ulinastatin in experimental rats. Rats were randomly divided into a sham control, a model ...control and an ulinastatin-treated group. Malondialdehyde (MDA) and superoxide dismutase (SOD) levels were determined. Serum amylase, serum aspartate aminotransaminase (AST), lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CKMD) activities, interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), nitric oxide (NO) and cardiac troponin I (nTnl) levels were examined. Results showed that ulinastatin decreased MDA levels and ameliorated the down-regulation of SOD activity. In addition, ulinastatin pretreatment may decrease serum AST, LDH and CKMD activities, IL-8, TNF-α, and nTnl levels, and enhance NO level. Our results demonstrated that oxidative injury occurred after IR and that ulinastatin exhibits significant protective effects against these effects.
High-frequency sensors can monitor water quality with high temporal resolution and without environmental influence. However, sensors for detecting key water quality parameters, such as total ...nitrogen(TN), total phosphorus(TP), and other water environmental parameters, are either not yet available or have attracted limited usage. By using a large number of high-frequency sensor and manual monitoring data, this study establishes regression equations that measure high-frequency sensor and key water quality parameters through multiple regression analysis. Results show that a high-frequency sensor can quickly and accurately estimate dynamic key water quality parameters by evaluating seven water quality parameters. An evaluation of the flux of four chemical parameters further proves that the multi-parameter sensor can efficiently estimate the key water quality parameters. However, due to the different optical properties and ecological bases of these parameters, the high-frequency sensor shows a better prediction performance for chemical parameters than for physical and biological parameters. Nevertheless, these results indicate that combining high-frequency sensor monitoring with regression equations can provide real-time and accurate water quality information that can meet the needs in water environment management and realize early warning functions.
With the rapid development of the Internet, the exponential growth of information resources makes it harder for users to retrieve information that is useful to themselves. But the advent of ...personalized recommendation systems has brought the hope and help to users. This paper introduces the background and meaning of the original Slope One static algorithm and the current researches. It thoroughly explores the improvement of Slope One algorithm at home and abroad, and clarifies the advantages and disadvantages of the algorithm. Based on the original Slope One static algorithm, an incremental Slope One algorithm is proposed. The advantage of incremental algorithm is that it can adapt to the instantaneous changes of data. Combined with the easy implementation, easy expansion and high accuracy of Slope One, Slope One incremental algorithm has good practicability.
Chronic myelogenous leukemia (CML) is characterized by the t(9;22) (q34;q11)-associated
fusion gene, which is an essential element of clinical diagnosis. As a traditional Chinese medicine, realgar ...has been widely used for the treatment of various diseases for >1,500 years. Inspired by nano-drug, realgar nanoparticles (NPs) have been prepared with an average particle size of <100 nm in a previous work. Compared with coarse realgar, the realgar NPs have higher bioavailability. As a principal constituent protein of caveolae, caveolin-1 (Cav-1) participates in regulating various cellular physiological and pathological processes including tumorigenesis and tumor development. In previous studies, it was found that realgar NPs can inhibit several types of tumor cell proliferation. However, the therapeutic effect of realgar NPs on CML has not been fully elucidated. In the present paper, it was demonstrated that realgar NPs can inhibit the proliferation of K562 cells and degrade Bcr-Abl fusion protein effectively. Both apoptosis and autophagy were activated in a dose-dependent manner in realgar NPs treated cells, and the induction of autophagy was associated with class I phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway. Morphological analysis indicated that realgar NPs induced differentiation effectively in CML cells. Furthermore, it was identified that Cav-1 might play a crucial role in realgar NP therapy. In order to study the effects of Cav-1 on K562 cells during realgar NP treatment, a Cav-1 overexpression cell model was established by using transient transfection. The results indicated that Cav-1 overexpression inhibited K562 cell proliferation, promoted endogenic autophagy, and increased the sensitivity of K562 cells to realgar NPs. Therefore, the results demonstrated that realgar NPs degraded Bcr-Abl oncoprotein, while the underlying mechanism might be related to apoptosis and autophagy, and Cav-1 might be considered as a potential target for clinical comprehensive therapy of CML.
Abstract Objective The aim of this study was to evaluate the effects of ZnCl2 on plaque-growth and vitality pattern of dental biofilm and to determine the optimum zinc concentration for the ...inhibition of plaque formation. Design Data were collected from nine volunteers for whom a special-designed acrylic appliance was prescribed after a careful dental check up. The volunteers rinsed twice daily for 2 min with ZnCl2 of 2.5, 5, 10, 20 mM as treatment and double distilled water (DDW) as control in respective assigned test weeks. The plaque index (PI) was assessed after 48 h of appliance wearing. The glass discs with the adhered biofilm were removed from the splints and stained with two fluorescent dyes. The biofilm thickness (BT) and bacterial vitality of the whole biofilm as well as the mean bacterial vitality (BV) of the inner, middle and outer layers of biofilm were evaluated under confocal laser scanning microscope (CLSM). Results PI, BT and BV of biofilms treated by various concentrations of ZnCl2 were reduced significantly when compared with the DDW group ( p < 0.05). PI, BT and BV of the 2.5 mM ZnCl2 group was significantly higher than groups of 5, 10, 20 mM ZnCl2 ( p < 0.05). The mean BV of the 3 layers (inner, middle and outer layers) showed that 2.5 mM ZnCl2 was the lowest concentration to inhibit BV in the outer layer, 5 mM was the lowest concentration to extend this inhibition of BV to the middle layer, and none of the concentrations investigated in this study has shown any effect on bacteria inhibition in the inner layer. Conclusion Zinc ions exhibited possible inhibitory effects on plaque formation, and have a promising potential to be used as an antibacterial agent in future dentifrices and mouthrinses.
Single-electron halogen bond: Ab initio study Wang, Yan-Hua; Zou, Jian-Wei; Lu, Yun-Xiang ...
International journal of quantum chemistry,
2007, Letnik:
107, Številka:
2
Journal Article
A high-accuracy calibration technique using a white paper and a front coating plane mirror is proposed in this paper for line-structured light vision sensors. This method shows advantages in two ...aspects. First, a white paper can gain a very high-quality light stripe due to its approximate ideal diffuse Lambertian sheet, which overcomes the problems associated with the strong reflecting light and serious burrs of the light stripe on conventional rigid targets. Second, based on a front coating plane mirror with lithographic feature points, we can obtain a bilateral symmetric structure similar to a virtual binocular stereo vision to recover the 3D coordinates of the light stripe centers on white paper with high accuracy. Front coating guarantees the coplanarity with the lithographic feature points and avoids imaging distortion caused by refraction during back coating. Therefore, front coating can be used to obtain high accuracy structural parameters of the virtual binocular stereo vision sensors. Meanwhile, for the light stripe and its image in the plane mirror are auto-epipolar with all the epipolar lines arranged in parallel. These lines intersect at a vanishing point in the camera image, and this epipolar constraint is used to complete the matching of the light stripe centers without the need for the camera parameters. Experiments are conducted to demonstrate the performance of the proposed method.
The goal of this study was to exam the efficacy of current DVH based clinical guidelines draw from photon experience for lung cancer radiation therapy on proton therapy. Comparison proton plans and ...IMRT plans were generated for 10 lung patients treated in our proton facility. A gEUD based plan evaluation method was developed for plan evaluation. This evaluation method used normal lung gEUD(a) curve in which the model parameter “a” was sampled from the literature reported value. For all patients, the proton plans delivered lower normal lung V5 Gy with similar V20 Gy and similar target coverage. Based on current clinical guidelines, proton plans were ranked superior to IMRT plans for all 10 patients. However, the proton and IMRT normal lung gEUD(a) curves crossed for 8 patients within the tested range of “a”, which means there was a possibility that proton plan would be worse than IMRT plan for lung sparing. A concept of deficiency index (DI) was introduced to quantify the probability of proton plans doing worse than IMRT plans. By applying threshold on DI, four patients’ proton plan was ranked inferior to the IMRT plan. Meanwhile if a threshold to the location of curve crossing was applied, 6 patients’ proton plan was ranked inferior to the IMRT plan. The contradictory ranking results between the current clinical guidelines and the gEUD(a) curve analysis demonstrated there is potential pitfalls by applying photon experience directly to the proton world. A comprehensive plan evaluation based on radio‐biological models should be carried out to decide if a lung patient would really be benefit from proton therapy.
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