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Cracked tooth is a common dental hard tissue disease.The involvement of cracks directly affects the selection of treatment and restoration of the affected teeth.It is helpful to choose more appropriate treatment options and evaluate the prognosis of the affected tooth accurately to determine the actual involvement of the crack.However, it is often difficult to accurately and quantitatively assess the scope of cracks at present.So it is necessary to find a real method of early quantitative and non-destructive crack detection.This article reviews the current clinical detection methods and research progress of cracked tooth in order to provide a reference for finding a clinical detection method for cracked tooth. [ABSTRACT FROM AUTHOR]

The paper has brought in the Hjorth Complexity parameter and combined it with Intrinsic time decomposition (ITD) algorithm as characteristic parameter index in order to implement accurate identification of multiple faults of rolling bearings. Firstly, concerning about the much uncertainty in manual setting of decomposition layer number in ITD, overdoing of automatic decomposition and the fact that a larger correlation coefficient of signal relates with the greater correlation of signals before and after decomposition and vice versa, the paper has carried out self-adaptive determination of the number of ITD decomposition layers. Secondly, regarding the insensitivity of Hjorth Complexity parameter to noise and the fact that with larger Complexity parameter, signals are simpler and it becomes more available to dig out characteristic information of fault from signals. With Complexity parameter as the index of characteristic parameter, option of optimal Proper rotation component (PRC) is made after ITD. Finally, through the comparison with other methods and the analysis of multiple faults of bearings, it indicates that correlation coefficient can self-adaptively determine the number of ITD decomposition layers and prevent from overdoing and underdoing of decomposition. The Hjorth Complexity parameter can be treated as index parameter to implement optimal PRC option, based on which multiple fault characteristics of bearings can be effectively extracted and the type precisely determined. • The decomposition layers of ITD are determined based on the correlation coefficient adaptive. • Hjorth parameter is introduced into the feature extraction of rolling bearing compound faults. • Complexity parameter is used as the index parameter of the optimal PRC selection. • Cross-correlation function is brought in to make mixed study on the acceleration signals from different sensors. • ITD is combined with Hjorth parameter. [ABSTRACT FROM AUTHOR]

Tracement of the origin of seafoods and aquatic products is an important issue for avoiding the falsification of production regions of aquatic products. Herein, by analyzing black tiger shrimp (Penaeus monodon) as a model of aquatic products, we demonstrated a method to trace the origin of aquatic products by analyzing the gut microbiome of black tiger shrimp (Penaeus monodon) collected from three commercial farms in China, via matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. Multivariate analysis was executed on the obtained mass spectrometric datasets of bacteria extracted and collected from shrimp samples with different production regions. The gut microorganisms of black tiger shrimps can be identified by scoring the gut microbiota of black tiger shrimps collected from three producing areas. The black tiger shrimp from three production regions were found with distinguished characteristics of bacterial prevalence in their digestive gland microbiota. The dominant bacteria genus in digestive gland microbiota from black tiger shrimp samples from the three production regions are completely different. Single-blind shrimp samples with unknown production region was successfully screened by comparing the detected MS data in different ways. This strategy can trace the production region of the analyzed shrimp samples in a quick and efficient mode. The application of the present protocol was further demonstrated by analyzing the biometric species from gill tissue of Chinese mitten crab (Eriocheir sinensis) samples collected from crab-producing areas in Jiangsu Province (China), that is, Taihu Lake, Gaoyou Lake, and Hongze Lake for tracing their production area. It is expected to extend the presently developed method to provide clues for the origin traceability of other aquatic products. • Tracement of the origin of seafoods is an important issue to avoid the falsification. • A method to trace the origin of aquatic products via MALDI-TOF MS was proposed. • The dominant bacteria in digestive gland microbiota from shrimps are different. • The origin of single-blind shrimp samples can be successfully traced. • The present method holds promise for the origin traceability of aquatic products. [ABSTRACT FROM AUTHOR]

• Sensibility of variance to variation of signal intensity is used to construct Hankel matrix to highlight fault feature. • Optimal scale of the variance series was determined by sample entropy to create a multi-scale Hankel matrix. • Proposed multiscale singular value method can effectively reduce noise and highlight fault feature information. • Proposed method is insensitive to installation positions of sensors and the fault type of rolling bearings. To solve the vulnerability of singular value denoising to the effective number of singular value orders and influence of Hankel matrix structure, the paper has proposed a multiscale singular value denoising algorithm (M-SVD). Meanwhile, in concerning that when a fault of bearing occurs, the fault feature information contained in vibration signal tends to be weak and complex, the M-SVD method is blended with variational mode decomposition (VMD) algorithm in identification. Firstly, when bearing faults occur, raw vibration acceleration signals are decomposed using the superiority of VMD algorithm for non-stationary signal; in addition, considering that with the larger difference between singular values of signal, feature information will be more obvious, the method takes advantage of sensibility of variance to signal intensity and proposes to constitute Hankel matrix based on variance feature of signal. During the construction of Hankel matrix, the method to determine effective length of variance sequence (optimal scale) has been brought forward by sample entropy which is able to precisely measure the regularity of signal and detect the weak change of signal. Furthermore, component signals are denoised in line with reconstructed Hankel matrix and the spectrum of signals denoised are selected to describe fault characteristic information and judge the failure types. For the sake of verification of the accuracy and effectiveness of proposed method, the paper has analyzed and verified the data of rolling bearing in 3 different failure types and 2 different installation positions of accelerometers. The comparative analysis with classical singular value difference spectrum (SVDS) and singular value median decomposition (SVMD) denoising has further proved that presented VMD combined M-SVD method can effectively restrain noise while retaining fault characteristic information of signal. Therefore, the identification for rolling bearing fault types can be implemented, accurately. [ABSTRACT FROM AUTHOR]

Abstract Marine organisms are naturally exposed to different environmental pollutants including organic pollutants and nanoparticles. The interactive effects between nanoparticles and other chemicals on aquatic organisms have raised concerns regarding the potential of nanomaterials as the vector for other chemicals. In the present study, the effect of nano zinc oxide (nZnO) on the bioavailability of triphenyltin chloride (TPTCl) was studied, and their combined acute and reproductive toxicity to the marine copepod Tigriopus japonicus were evaluated. At experimental concentration ranges of nZnO in this study, the percentage of dissolution of Zn2+ was relative stable (from 62% to 66%), and nZnO did not affect the bioavailability of TPTCl to the copepods. The acute toxicity of binary mixtures of nZnO/TPT was equivalent to that of the mixture of Zn2+/TPT. In agreement with the decrease in TPTCl's LC 50 values at the presence of nZnO, their interacting effect was synergistic based on response addition response surface model, and the interacting parameter was modelled to be −1.43. In addition to acute toxicity test, reproductive toxicity tests revealed that exposure to nZnO and TPTCl didn't affect the successful mating rate and the number of nauplii in the 1st brood, but they extended the time for the eggs to hatch from 2.53 days to 3.94 and 3.64 days, respectively. The exposure to nZnO/TPTCl mixture delayed the time to hatch to 5.78 days. Graphical abstract Image 1 Highlights • LC 50 values of TPT decreased at the presence of nZnO. • Interaction between TPT and nZnO was equivalent to TPT and Zn2+. • NZnO did not affect the bioavailability of TPT. • The interaction of TPT and nZnO was synergistic according to RARS model. • RARS model better fitted the data than CARS model. This study observed synergistic effect between nZnO and TPTCl on the marine copepod Tigriopus japonicus by applying response addition response surface model. [ABSTRACT FROM AUTHOR]

• Take advantage of sensibility of Activity parameter to vibration intensity to describe the intensity of signals and identify different rub-impact states. • Make use of the sensitivity of Mobility parameter to signal state to determine the occurrence of rub-impact fault. • The sensitivity of Complexity parameter to signal complexity will be relied on to identify the different rub-impact states of equipment. • Hjorth parameters can be treated as the characteristic parameters for identifying of rub-impact fault and location. Hjorth parameters reveals Activity, Mobility and Complexity of signals. From this, the paper has proposed the scheme to identify a rotor–stator rub-impact fault and occurrence location by Hjorth parameters. Firstly, the approach has given an analysis to the difference of Hjorth parameters of signals and verified the sensibility of Hjorth parameters to running state of equipment; secondly, in the same running state of equipment, the consistency and robustness of Hjorth parameters of signals from the same sensor have been analyzed and proved; thirdly, for verifying the sensitivity of sensors installation locations to rub-impact fault and occurrence locations, Hjorth parameters of signals from different sensors have been analyzed; finally, the calculated Hjorth parameters are used as feature vector, and K-nearest neighbor (KNN) classification algorithm is employed for identifying a rub-impact fault and determining the rub-impact locations. The results indicate that proposed method can accurately identify the rub-impact fault and occurrence locations. [ABSTRACT FROM AUTHOR]

• Vibration signal from casing of aeroplane engine is selected. • Information fusion, ITD and Complexity parameter in Hjorth parameters is combined. • PRC associated with the least Complexity parameter in Hjorth parameters is removed. • Complexity parameter can be regarded as criterion to select effective PRCs. • Mixed faults of intershaft bearing of aeroplane engine can be correctly identified. To make correct judgment on the mixed faults of intershaft bearing of aeroplane engine, the paper has proposed a feature option method. This method works by decomposing cross-correlation function (CCF) of homogeneous information from casing with intrinsic time scale decomposition (ITD) for the separation and blending of signals. Furthermore, option of proper rotation components (PRCs) for fault identification is made by abandoning the PRC related with the least Complexity parameter in Hjorth parameters. Moreover, signal is reconstructed based on the autocorrelation function (AF) of residual PRCs. Finally, according to the frequency spectrum of signal reconstructed, fault features corresponding to intershaft bearing are extracted and fault types estimated. The result indicates that the Complexity parameter in Hjorth parameter can be used as an evaluation index to implement the selecting of sensitive fault components. Furthermore, the mixed fault types which come from intershaft bearing of aeroplane engine could be judged correctly. [ABSTRACT FROM AUTHOR]

Ternary blend strategy has been proved to be an effective method to improve the photovoltaic performance for organic solar cells (OSCs). In this work, efficient ternary OSCs are fabricated with one donor PBDB-T and two acceptors Ph -DTDP-TIC and PC 71 BM. Ternary components can form a cascade energy level alignment when PC 71 BM as the third component to enhance charge transfer between the non-fullerene acceptor Ph -DTDP-TIC and PC 71 BM, achieving improved charge separation and collection in the ternary OSCs. Meanwhile, it demonstrated that PC 71 BM as the third component can also improve the morphology of the active layer and form suitable phase separation scale. As a results, two binary devices (PBDB-T: Ph -DTDP-TIC and PBDB-T:PC 71 BM) exhibit moderate power conversion efficiencies (PCEs) of 8.80% and 6.74%, respectively. While, the optimized PBDB-T: Ph -DTDP-TIC:PC 71 BM ternary device can produce an enhanced PCE of 11.07% through adding 40 wt% PC 71 BM in acceptors, originating from simultaneously improved J sc of 17.57 mA/cm2 and FF of 70.90%. Our work demonstrated the ternary strategy with PC 71 BM as the third component can promote charge transfer and transport to improve photovoltaic performance for OSCs. [Display omitted] • The enhanced charge transfer channel formed with dipyran acceptor as the addition of PC 71 BM. • PC 71 BM as ternary component could effectively improve blend morphology. • Ternary strategy could reach the same goal as molecular tailoring in dipyran acceptor. [ABSTRACT FROM AUTHOR]

• Intrinsic Time-scale Decomposition and Graph Signal Processing is integrated. • A PR component with minimum Laplacian Energy index is chosen. • The ITD-GSP can precisely provide the characteristic frequency of compound faults. • The ITD-GSP algorithm is insensitive to the installation direction of sensors. The diagnosis of compound faults of rolling bearing is extremely difficult due to the nonlinearity and non-stationary of signal. With the purpose of extracting the compound faults from rolling bearings of aero-engine, efforts were made to integrate Intrinsic Time-scale Decomposition (ITD) and Graph Signal Processing (GSP), namely the ITD-GSP methodology. A PR component (obtained by ITD algorithm) with minimum Laplacian Energy (LE) index is chosen as the optimal rotational component to identify types of compound fault of rolling bearing. The result indicates that the proposed ITD-GSP methodology can precisely and effectively provide the characteristic frequency of compound faults no matter in which direction of sensors (vertical and horizontal) and which type of compound faults of rolling bearing. On the contrary, the mainstream schemes of fault analysis using ITD algorithm (correlation coefficients or kurtosis as the basis to screen optimal rotational component) cannot. [ABSTRACT FROM AUTHOR]

Low-level fluoride in the oral environment for a long sustained period is more effective for preventing caries. However, the current fluoride delivery methods have a short fluoride retention time and high-dose fluoride administration may increase the risk of dental fluorosis. This study developed a novel fluoride strip based poly(propylene carbonate) (PPC), which can improve oral fluoride retention for desirable anticaries effect with minimal side effects. The fluoride strips based PPC (NaF-PPC strips) with different fluoride contents (0, 1.25, 2.5 and 5 wt.%) were developed by melt-blending method. The physico-chemical characteristics, drug loading, drug release properties, remineralization and antibacterial efficacy and biocompatibility of NaF-PPC strips were investigated. The in vitro drug release studies indicated that fluoride release in a sustained manner with no initial burst release and approximately 100% of fluoride ions were released from PPC strips over 24 days. NaF-PPC strips exhibited excellent remineralization and antibacterial potential when fluoride content up to 5%. Combination with biocompatibility, 2.5% NaF-PPC strips could be a promising fluoride application for preventing caries. This work provides an effective and novel topical fluoride delivery for general use. [Display omitted] [ABSTRACT FROM AUTHOR]