Heave Motion Measurement by Adaptive Filter Based on Longuet-Higgins Wave Model

A method is proposed to obtain heave motion information based on the Longuet-Higgins wave model. The Longuet-Higgins wave model which is closer to the sea wave is introduced. Based on it, random process of the noise is analyzed and the highpass filter is designed to reduce errors. Then it is the key point in this article that an adaptive algorithm is put forward because of the complexity of the waves. The algorithm adjusts the cutoff frequency to reduce the amplitude attenuation of the filter by analyzing the wave. For the same reason the comprehensive parameter of the phase compensation can be also obtained by the algorithm. Simulation measurement results show that under the rough sea situation the maximum value of absolute error is 0.4942 m according to the normal method, the method is 0.1170 m, and the average error ratio of the rough sea test reduces to 3.89% from 12.54%, which demonstrates that the adaptive filter is more effective in measuring heave movement. A variety of simulation cases show that the adaptive filter can also improve the precision of the heave motion under different sea situations

Clinical researchMaternal mRNA expression levels of H19 are inversely associated with risk of macrosomia

INTRODUCTION: To investigate the associations between the mRNA levels of H19 in term placenta and risk of macrosomia. MATERIAL AND METHODS: Term placentas were collected from 37 macrosomia and 37 matched neonates with normal birth weight (controls) born in Changzhou Women and Children Health Hospital, Jiangsu province, P. R. China from March 1 to June 30, 2008. The mRNA levels of H19 in those placentas were measured by real-time polymerase chain reaction (PCR). Simple and multiple logistic regression models were used to explore the risk factors in the development of macrosomia. All analyses were performed using Stata 10.0 (StataCorp, College Station, Texas, USA). RESULTS: The average H19 mRNA level of the macrosomia group was 1.450 ±0.456 while in the control group it was 2.080 ±1.296. Based on the result of Student's t test, there was a significant difference in H19 mRNA level between the macrosomia group and the control group (p = 0.008). After controlling for potential confounders, the multivariable adjusted odds ratio (OR) of macrosomia for those in the highest tertile of H19 mRNA level was 0.12 (95% CI: 0.02-0.59) when compared to those in the lowest tertile (p for linear trend = 0.009). CONCLUSIONS: The term placental H19 mRNA levels were inversely related to the occurrence of macrosomia. Our findings suggest that the low expression of H19 mRNA may contribute to the development of macrosomia

Design and Experiment of Lightweight Dual-Mode Automatic Variable-Rate Fertilization Device and Control System

China’s agricultural facilities are developing rapidly and are mainly operated through household contracting. Due to a lack of suitable variable-rate fertilization devices, manual and blind fertilization still widely exists, resulting in fertilizer waste and environmental pollution. Meanwhile, existing fertilization devices cannot simultaneously meet the needs of different fertilization methods for crop cultivation, increasing the cost of mechanized fertilization. This study developed a lightweight dual-mode automatic variable-rate fertilization device and control system for strip fertilization and spreading fertilization. The least squares method was used to analyze the amount of fertilizer discharged per second at different volumes and rotational speeds of the fertilization device. The quadratic polynomial model fits well, with determination coefficients greater than 0.99. The automatic variable strip fertilization and spreading fertilization control models were established. Experiments with strip fertilization and spreading fertilization were carried out. The results of strip fertilization experiments show that the maximum relative error (Re) for granular nitrogen fertilizer (NF) was 6.81%, compound fertilizer (CF) was 6.2%, organic compound fertilizer (OCF) was 6.83%, and the maximum coefficient of variation (Cv) of uniformity was 8.91%. The results of spreading fertilization experiments show that the maximum Re of granular NF was 7.31%, granular CF was 6.76%, granular OCF was 7.43%, the Cv of lateral uniformity was 9.88%, and the Cv of total uniformity was 14.17%. The developed fertilization device and control system can meet the needs of different fertilization amounts, types, and methods for facility crop cultivation at different stages. This study’s results can provide a theoretical basis and technical support for designing and optimizing multifunctional precision variable-rate fertilization devices and control systems

Model-Free Method for Damage Localization of Grid Structure

A model-free damage identification method for grid structures based on displacement difference is proposed. The inherent relationship between the displacement difference and the position of structural damage was deduced in detail by the Sherman–Morrison–Woodbury formula, and the basic principle of damage localization of the grid structure was obtained. That is, except for the tensile and compressive deformations of the damaged elements, the deformations of other elements were small, and only rigid body displacements occurred before and after the structural damage. According to this rule, a method for identifying the position of the damage was proposed for the space grid structure by using the rate of change of length for each element. Taking a space grid structure with a large number of elements as an example, the elastic modulus reduction method was used to simulate the damage to the elements, and the static and dynamic test parameters were simulated respectively to obtain the difference in displacement before and after the structural damage. The rate of change of length of each element was calculated based on the obtained displacement difference, and data noise was added to the simulation. The results indicated that the element with the larger length change rate in the structure was the most likely to be damaged, and the damaged element can be accurately evaluated even in the presence of noise in data

High-dose vitamin D metabolite delivery inhibits breast cancer metastasis

Besides its well-known benefits on human health, calcitriol, the hormonally active form of vitamin D3, has been being evaluated in clinical trials as an anticancer agent. However, currently available results are contradictory and not fundamentally deciphered. To the best of our knowledge, hypercalcemia caused by high-dose calcitriol administration and its low bioavailability limit its anticancer investigations and translations. Here, we show that the one-step self-assembly of calcitriol and amphiphilic cholesterol-based conjugates leads to the formation of a stable minimalist micellar nanosystem. When administered to mice, this nanosystem demonstrates high calcitriol doses in breast tumor cells, significant tumor growth inhibition and antimetastasis capability, as well as good biocompatibility. We further reveal that the underlying molecular antimetastatic mechanisms involve downregulation of proteins facilitating metastasis and upregulation of paxillin, the key protein of focal adhesion, in primary tumors