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ABSTRACTObjectiveTo develop and validate a population pharmacokinetic (PPK) model of oral olanzapine in pediatric Chinese patients in order to individualize therapy in this population.MethodsA total of 897 serum concentrations from 269 pediatric patients taking oral olanzapine (ages 8–17 years) were collected. Demographic parameters, biological characteristics and concomitant medications were investigated as covariates. The data were analyzed using a nonlinear mixed-effects modeling approach. Bootstrapping (1000 runs), normalized prediction distribution error (NPDE), and external validation of 62 patients were employed. Simulations were performed to explore the individualized dosing regimens in various situations.ResultsThe one-compartment model with first-order absorption and elimination had an apparent clearance (CL/F) of 10.38 L/h, a distribution volume (V/F) of 9.41 L/kg and an absorption rate constant (Ka) fixed at 0.3 h−1. The equation was CL∕F (L∕h) = 10.38 × (body weight∕60)0.25×1.33 (if male) × 0.71 (if co-occurrence of infection) × 0.51 (if co-therapy with fluvoxamine) × 1.27 (if co-therapy with sertraline) × 1.43 (if co-therapy with valproate). The final model had satisfactory stability, robustness, and predictive ability. The results from a simulation suggested the oral olanzapine doses required for male and female pediatric patients weighing between 40 and 60 kg without co-medication were 10–15 mg/day and 7.5–10 mg/day, respectively, and dosage adjustments should be based on sex and body weight; and co-administrated with valproate, sertraline, or fluvoxamine.ConclusionThis model may help individualize optimum dosing of oral olanzapine for pediatric patients.

Herein, complex coupling flow from layer-multiplying elements (LMEs) and the postdrawing process were applied to in situ-generated flattened poly(lactic acid) (PLA) phase domains surrounded by poly(ε-caprolactone) (PCL) interface crystals in each confined PCL layer. Different postdrawing ratios (PDRs) were used to explore the structural development of PCL/PLA blend films with gradually decreasing layer space. Scanning electron microscopy (SEM), two-dimensional wide-angle X-ray diffraction (2D-WAXD), 2D small-angle X-ray scattering (2D-SAXS), polarized Fourier transform infrared reflection (FTIR), and differential scanning calorimetry (DSC) characterizations demonstrated the evolution behavior of phase, crystallites, and amorphous chains of PCL and PLA, including the transformation from spherical to flattened PLA domains with a larger length (diameter) and width-to-thickness ratio (∼2.24), the fragmentation and packing behavior of crystallites at PDR < 6, and the alignment behavior of amorphous chains at PDR > 6. As a result, the dynamic rheological storage modulus of the produced PCL/PLA blend films exhibited an impressive 4 orders of magnitude improvement at low frequency, and the tensile strength and elastic modulus at room temperature increased 186.4 and 277.5%, respectively, as PDR increased from 1 to 21. The study findings provide insight for applying the LME-postdrawing technique to the performance regulation of biodegradable materials to widen their applications, based on controllable phase morphology and confined interface construction.

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For the non-stationary vibration signals of wind tower, using a new method based on KPCA to eliminate the interference of the vibration signal. After cancellation noise according to the method based on EMD, the vibration signals are decomposed and the vibration characteristics of the signals are finally extracted. The experimental analysis indicates that this method can provide an effective reference for the health detection of wind tower.

Nonlinear processing techniques are very important tools in signal and image processing. One of the most significant classes is based on order statistics, which depends on data sorting algorithm. The sorting algorithm is very time consuming and intractable for vector data. Therefore, it is extremely urgent to put forward a fast algorithm to compute the r-th order statistics without sorting operation. The ITM and ITTM filter proposed an iteration algorithm to approach the median, from the mean. It is reasonab to generalize to the other order statistics by building a new data set Xp which is composed by the elements of the original set X. It makes the r-th order statistics of X to be the median of Xp. Then, estimating the median of the new set Xp by the ITTM algorithm, the output is estimation value of x(r).

In view of the existing of low frequency hydrophone in signal detection problems such as low sensitivity, frequency range is small, In this paper, application of PVDF piezoelectric film as sensitive material of low frequency hydrophone, use its advantages as fast response, high sensitivity, good mechanical properties, and so on [1], designed a kind of low frequency hydrophone, experiments are carried out to study the detection of low frequency signal. This paper introduces the structure, material and size of the hydrophone, and analyzes the experimental data. Experiments show that the sensor stability and high sensitivity, can effectively detect the low frequency acoustic wave in the water.

For differences of time-domain energy distribution of different gear fault vibration signal, an analytical method based on local mean decomposition (LMD) and least squares support vector machine (LS-SVM) is proposed to apply to gear fault diagnosis. First vibrational signal of gear is decomposed into a series of product functions (PF) by LMD method. Then extracting energy characteristic parameters of PF components which contain main fault information to constitute a fault feature vectors, which is considered as input sample of well-trained LS-SVM, and then identifying working state and fault type of different gear can be identified accurately and effectively by diagnostic method based on LMD and LS-SVM.

For a problem of mode mixing occurs in implementation process of local mean decomposition (LMD) method, an analytical method based on ensemble local mean decomposition (ELMD) and neural network is proposed to apply to fault diagnosis of rolling bearing, the vibrational signal of rolling bearing is decomposed into a series of product functions(PF) by ELMD method. The PF components which contain main fault information are selected to perform a further analysis. The kurtosis coefficient and energy characteristic parameters extracted from these PF components can be used as the input parameters of the neural network to identify the working status and fault types of rolling bearing. Through the analysis of rolling bearing with fault-free, inner-race fault and outer-race fault, the results indicate that the method based on ELMD and neural network has a higher failure recognition rate than the method based on wavelet packet analysis and neural network, and the working status and fault types of rolling bearing can be identified accurately and effectively.

For empirical mode decomposition (EMD) of Hilbert-Huang transform (HHT) exists the problem of mode mixing. An analysis method based on ensemble empirical mode decomposition (EEMD) is proposed to apply to fault diagnosis of rolling bearing. This paper puts forward, after signal pretreatment, applying EEMD method to acquire the intrinsic mode function (IMF) of fault signal. Then according to correlation coefficient for IMFs and the signal before decomposing by EEMD method, some redundant low frequency IMFs produced in the process of decomposition can be eliminated, then the effective IMF components are selected to perform a local Hilbert marginal spectrum analysis, then fault characteristics are extracted. Through the vibration analysis of inner-race fault bearing it shows that this method can be effectively applied to extract fault characteristics of rolling bearing.

Air-fuel ratio, a major parameter of petrol engineer, directly affects the power, economy and indicators of exhaust emission of engine. To make the air-fuel ratio in the best state, the air flow entering into cylinder must be measured accurately. Due to gaseous property of air itself, the flow detection is greatly interfered by temperature and pressure. In the article, we used surface acoustic wave(SAW) technique combined with temperature and pressure compensation and made a detection device for engine intake, which was less interfered by temperature and pressure with high accuracy and wide measuring range. The paper introduced the working principle of SAW air flow sensor and its mathematic model, and discussed the development, signal detection and error processing of sensor. The results showed that SAW sensor could better overcome the interference of temperature and pressure, and then accurately got the air flow value of engine with preferable repeatability and reliability.

This paper discusses about the methods of ultrasonic nondestructive testing applied in the hydraulic cylinder production process; represents how to detect the defects of the raw material of cylinder barrel such as bubbles, cracks, impurity and test the steel tube thickness with the principle of ultrasonic thickness measurement; introduces how to select raw materials through the measured thickness, detect the defects in the machining process and implement preliminary qualifying examination for assembled hydraulic cylinder. The actual application shows that the method can improve the qualification of hydraulic cylinder production effectively.

In order to solve time synchronization problem of wireless sensor network, combined with the broadcast characteristics of wireless transmission and bi-directional message mechanism and the characteristics of clustering network, this paper presents an improved time synchronization algorithm HLTN based on clustering network and the simulation experiment by NS-2 simulation platform and analyzed the results.

Many factors may lead to internal structure of travelling crane injured when it is working. Therefore, it is an important problem of industry safety to detect the main girder. In this paper, a non-destructive testing method is presented. The white noise on the main girder was generated with artificial incentive. Special PVDF piezoelectric film sensor was used to detect the change of resonant frequency of main girder of traveling crane and the frequency was analyzed to judge the non-destructive health status of the main girder. The experiment results show that traveling crane survey method based on PVDF piezoelectric film sensor has a good accuracy and feasibility.

This paper mainly deals with the problem of oil pipeline leak and difficult to detect its location, combining the trait of our country’s oil pipeline, researching the leak detection and location based on the PVDF piezoelectric sensors. This paper firstly describes the domestic status of pipeline leak detection, and then gives a brief introduction for the PVDF piezoelectric film, finally discusses the pipeline leak detection and location system based on PVDF piezoelectric sensors. Experiments show that the use of PVDF piezoelectric sensors on pipeline leak detection, the leak can be correctly identified, and improving the detection sensitivity and leak resolution, effectively reducing the false alarm rate.

The measurement of low and ultra-low frequency vibration has always been a very difficult problem. In this paper, a new structure is designed and a new type of low and ultra-low frequency accelerometer is developed by using a sensitive element PVDF. A new type of sensor structure and working principle are discussed and mathematical model and characterize are analyzed in this paper. The result confirmed that this design method can improve sensitivity, precision and performance of the sensor, overcome the acceleration interference of other direction in the vertical axis upwards, and improve the unilateralism and stability of the sensor.

Boswellic acids are the effective components of gum resin of Boswellia serrata, which has anti-inflammatory properties. Recent studies on brain tumors and leukemic cells indicate that boswellic acids may have antiproliferative and apoptotic effects with the mechanisms being not studied in detail. We studied their antiproliferative and apoptotic effects on colon cancer cells and the pathway leading to apoptosis. HT-29 cells were treated with β-boswellic acid (BA), keto-β-boswellic acid (K-BA) and acetyl-keto-β-boswellic acid (AK-BA), respectively. Apoptosis was determined by flow cytometry, by cytoplasmic DNA–histone complex and the activity of caspase-3. The cleavage of poly-(ADP-ribose)-polymerase (PARP) and expression of Fas were examined by western blot. Specific caspase inhibitors, polyclonal Fas antibody, and antagonistic Fas antibody ZB4 were employed to elucidate apoptotic pathways. DNA synthesis and cell viability were examined. Both K-BA and AK-BA increased cytoplasmic DNA–histone complex dose-dependently and increased pre-G1 peak in flow cytometer analysis, with the effects of AK-BA being stronger than K-BA. BA only increased the formation of DNA–histone complex at a high concentration. K-BA and AK-BA increased caspase-8, caspase-9 and caspase-3 activities accompanied by cleavage of PARP. The effects of AK-BA on formation of cytoplasmic DNA histone and on caspase-3 activation were 3.7- and 3.4-fold, respectively, more effective than those induced by camptothecin. The apoptosis induced by AK-BA was inhibited completely by caspase-3 or caspase-8 inhibitor and partially by caspase-9 inhibitor. ZB4 blocked exogenous Fas ligand-induced apoptosis, but had no effect on AK-BA-induced apoptosis. AK-BA had no significant effect on expression of Fas. Apart from apoptotic effect, these acids also inhibited [3H]thymidine incorporation and cell viability to different extent. In conclusion, boswellic acids, particularly AK-BA and K-BA have antiproliferative and apoptotic effects in human HT-29 cells. The apoptotic effect is mediated via a pathway dependent on caspase-8 activation but independent of Fas/FasL interaction.

Boswellic acids are the effective components of gum resin of Boswellia serrata, which has anti-inflammatory properties. Recent studies on brain tumors and leukemic cells indicate that boswellic acids may have antiproliferative and apoptotic effects with the mechanisms being not studied in detail. We studied their antiproliferative and apoptotic effects on colon cancer cells and the pathway leading to apoptosis. HT-29 cells were treated with beta-boswellic acid (BA), keto-beta-boswellic acid (K-BA) and acetyl-keto-beta-boswellic acid (AK-BA), respectively. Apoptosis was determined by flow cytometry, by cytoplasmic DNA-histone complex and the activity of caspase-3. The cleavage of poly-(ADP-ribose)-polymerase (PARP) and expression of Fas were examined by western blot. Specific caspase inhibitors, polyclonal Fas antibody, and antagonistic Fas antibody ZB4 were employed to elucidate apoptotic pathways. DNA synthesis and cell viability were examined. Both K-BA and AK-BA increased cytoplasmic DNA-histone complex dose-dependently and increased pre-G(1) peak in flow cytometer analysis, with the effects of AK-BA being stronger than K-BA. BA only increased the formation of DNA-histone complex at a high concentration. K-BA and AK-BA increased caspase-8, caspase-9 and caspase-3 activities accompanied by cleavage of PARP. The effects of AK-BA on formation of cytoplasmic DNA histone and on caspase-3 activation were 3.7- and 3.4-fold, respectively, more effective than those induced by camptothecin. The apoptosis induced by AK-BA was inhibited completely by caspase-3 or caspase-8 inhibitor and partially by caspase-9 inhibitor. ZB4 blocked exogenous Fas ligand-induced apoptosis, but had no effect on AK-BA-induced apoptosis. AK-BA had no significant effect on expression of Fas. Apart from apoptotic effect, these acids also inhibited [(3)H]thymidine incorporation and cell viability to different extent. In conclusion, boswellic acids, particularly AK-BA and K-BA have antiproliferative and apoptotic effects in human HT-29 cells. The apoptotic effect is mediated via a pathway dependent on caspase-8 activation but independent of Fas/FasL interaction.

In this paper, we use two algorithms which include least square fitting and correlation method to test high-speed rotor balancing at low-speed, and this is a new means of dynamic balance test. For low-speed test system of balancing, based on the hardware circuit, we use the algorithms supplied by virtual instrument to analyze the fundamental frequency information of the vibration, and ultimately we come up a testing method with a combination of hardware and software. Obtained data on rotating machinery's repair and maintenance is very useful.